HomeMy WebLinkAbout004 - 02/02/2010 - ADOPTING STANDARDS FOR INTERCONNECTION OF ELECTRIC GENERATION FACILITIES TO THE FORT COLLINS ELECTRI ORDINANCE NO. 004, 2010
OF THE COUNCIL OF THE CITY OF FORT COLLINS
ADOPTING STANDARDS FOR INTERCONNECTION OF
ELECTRIC GENERATION FACILITIES TO THE FORT COLLINS
ELECTRIC DISTRIBUTION SYSTEM
WHEREAS, in view of the fact that the City Council recognizes and places high value on
the viability of the City's electric utility and on allowing City property owners to provide electric
service to their own properties under certain conditions; and
WHEREAS, the connection of customer-owned generating facilities to the Fort Collins
electric distribution system entails complex technical and safety issues; and
WHEREAS, staff believes that requiring customers and their generating facilities to meet
certain terms and conditions will serve to protect the viability and safe operation of the Fort Collins
electric distribution system; and
WHEREAS, staff has worked with a consultant to develop certain Standards for
Interconnection of Electric Generation Facilities to the Fort Collins Electric Distribution System(the
"Standards"),a copy of which is attached hereto and incorporated herein by this reference as Exhibit
"A"; and
WHEREAS,on November 9,2009,the Fort Collins Electric Board reviewed and considered
proposed standards in a form substantially similar to those contained in Exhibit "A" and voted
unanimously to recommend that the City Council adopt such standards; and
WHEREAS, modifications made to the standards presented to the Electric Board are
reflected in Exhibit "A" and include corrections of typographical errors, some corrections to
mathematical equations and revisions suggested by citizen comments; and
WHEREAS, the adoption of the Standards will protect the viability and security of the Fort
Collins electric distribution system, promote safety of electric service customers, staff, and
interconnected generators, and establish baseline technical requirements for interconnection.
NOW, THEREFORE, BE IT ORDAINED BY THE COUNCIL OF THE CITY OF FORT
COLLINS as follows:
Section 1. That adoption of the Standards is necessary to encourage City property owners
to provide electric service to their own properties under certain conditions.
Section 2. That adoption of the Standards is necessary to protect the viability of the Fort
Collins electric distribution system.
Section 3. That adoption of the Standards is necessary to promote safety of electric
service customers, staff, and interconnected generators.
Section 4. That the Standards are hereby approved and adopted.
Introduced, considered favorably on first reading, and ordered published this 19th day of
January, A.D. 2010, and to be presented for final passage on th day of February, A.D. 10.
• v
A
' Mayor
ATTEST: '
City Clerk
Passed and adopted on final reading on the 2nd day of ruary, A.D. 2010.
r
Mayor
ATTEST:
-City Clerk
Exhibit A
City of
ort Collmins
41000
Utility
Services
INTERCONNECTION STANDARDS
FOR GENERATING FACILITIES ( GF ) CONNECTED TO
THE FORT COLLINS DISTRIBUTION SYSTEM
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rl
January 2010
TABLE OF CONTENTS
1 .0 SCOPE AND GENERAL REQUIREMENTS ................................................................................................... 2
1 . 1 SCOPE AND INTENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1 .2 SYSTEM PHASE AND VOLTAGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1 . 3 SYSTEM RECLOSING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1 .4 ISLANDING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1 . 5 SYNCHRONIZING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1 . 6 IMPROPER OPERATION OF THE GF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1 . 7 SYSTEM CAPACITY LIMITATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1 . 8 SUBMITTAL REQUIREMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.0 STANDARDS AND DEFINITIONS................................................................................................................... 4
2 . 1 STANDARDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2 .2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.0 GF EQUIPMENT AND INSTALLATION REQUIREMENTS ...................................................................... 5
3 . 1 GENERAL REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3 .2 INTERCONNECTION DISCONNECT SWITCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3 .3 DEDICATED TRANSFORMER AND ADDITIONAL PRIMARY PROTECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3 .4 INTERRUPTING DEVICES REQUIRED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3 . 5 SYSTEM PROTECTIVE FUNCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3 .6 MOMENTARY PARALLELING GENERATION FACILITIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.0 FACILITY GROUNDING ................................................................................................................................ 10
4. 1 EQUIPMENT BONDING CONDUCTOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.2 SURGE PROTECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.3 SYSTEM GROUNDING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5.0 PREVENTION OF INTERFERENCE AND UNACCEPTABLE OPERATING CONDITIONS ............. 12
5 . 1 VOLTAGE REGULATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5 .2 SYSTEM VOLTAGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5 . 3 SYSTEM FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5 .4 SYNCHRONIZATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5 . 5 FLICKER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5 . 6 HARMONICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5 .7 POWER FACTOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6.0 MONITORING PROVISIONS......................................................................................................................... 16
6 . 1 METERING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6 .2 MONITORING AND CONTROL REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
7.0 TESTING ............................................................................................................................................................ 17
7 . 1 COMMISSIONING TESTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
7 .2 PERIODIC MAINTENANCE TESTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
7 .3 QUALIFIED PERSONNEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
8.0 DESIGN CHANGES .......................................................................................................................................... 18
9.0 LIABILITY AND INSURANCE....................................................................................................................... 21
APPENDIX A-TYPICAL ONE-LINE INDUCTION GENERATOR BETWEEN 50KW AND 100KW .................... 20
APPENDIX B-TYPICAL ONE-LINE INVERTER CONNECTED GENERATOR BELOW 1000KW. .................... 21
APPENDIX C-TYPICAL ONE-LINE SYNCHRONOUS GENERATOR 50KW AND ABOVE ................................ 22
APPENDIX D-TYPICAL ONE-LINE INDUCTION GENERATOR LARGER THAN 100KW ................................ 23
APPENDIX E-TYPICAL ONE-LINE INVERTER CONNECTED GENERATOR LARGER THAN 1000KW ...... 24
1 . 0 Scope and General Requirements
1 . 1 Scope and Intent
The requirements contained in this document apply to all generation sources connected to the FCU
distribution system 5MW and below at any one location . Any and all connections to the FCU
distribution system and any aspect of such connection are subject to FCU review and such
connections shall not be permitted unless approved by FCU . The operation and design of any GF
must meet all of the requirements contained in this document, any written agreement between FCU
and the Operator, as well as any applicable requirements contained in Chapter 26 of the Fort Collins
Municipal Code and Fort Collins Utilities Electric Service Rules and Regulations .
Any location where the aggregate total generation exceeds 5MW may require additional study by
FCU . This study will consider the specific feeder where the GF is proposed to be connected . If the
addition of any GF causes the total amount of generation by all sources on that feeder to exceed
50% of the minimum load on that feeder, additional study by FCU is required and the requirements
produced as a result of that study may exceed those in this document. If the GF source to be added
is highly variable such as wind or solar, and the total amount of wind or solar generation by all
sources on that feeder exceeds 13 . 3% of the feeder capacity , or if the total of all the wind or solar
generation on any substation exceeds 13 . 3% of the substation transformer size , additional study by
FCU is required and the requirements produced as a result of that study may exceed those in this
document.
Protection and safety devices are intended to provide protection for the FCU distribution system ,
FCU utility workers , FCU customers and the general public . Protective devices installed on the GF
are designed to ensure that the fault current supplied by the GF will be interrupted in the event a fault
occurs on the FCU distribution system . When a fault occurs , the GF must be designed to
automatically disconnect from the FCU distribution system until the distribution system is restored to
normal operation .
Any source not explicitly described in this document will require special study before it is allowed to
interconnect to FCU .
1 .2 System Phase and Voltage
The GF may interconnect to the system at any service voltage available at the site . Additional
voltages may be arranged with FCU on a case-by-case basis , subject to FCU approval . If the site
contains a three-phase system the GF equipment must be three-phase . If only a single phase
service is available , a single- phase GF may be allowed . The maximum nameplate rating of all the
single-phase generators at any GF shall not exceed 20 kVA if connected line-line . When the site
contains a center-tapped single-phase service , machines may be connected between phase and the
center-tapped neutral providing the maximum nameplate rating of the generator connected does not
exceed 5 kVA.
1 . 3 System Reclosing
Automatic reclosing is generally not utilized on the FCU distribution systems to clear temporary
faults ; however, in the cases and locations where automatic reclosing is used , the GF must be
designed to ensure that the GF will disconnect from the distribution system in the event an automatic
reclose occurs . Normally the GF will not be allowed to interfere with automatic reclosing where it
exists ; however, industry standards require that a GF must automatically disconnect from an
islanded system within two seconds . If the existing reclosing interval is faster than two seconds FCU
will reset it to accommodate the GF .
1 .4 Islanding
Islanding occurs when a GF becomes separated from the main generation source on a distribution
system , but continues to independently serve a portion of the distribution system . GF's shall be
Rev 8 . 0 January 2010 2
equipped with protective devices and controls designed to prevent the generator from being
connected to a de-energized distribution system . Islanding is not permitted on the FCU distribution
system .
1 . 5 Synchronizing
Synchronization of the GF with the FCU system must be done automatically . Any proposal to allow
manual synchronization is subject to review and approval by FCU . All GF 's must use protective
devices that prevent electrically closing a GF that is out of synchronization with the distribution
system . FCU will under no circumstances be responsible or liable for any damage done due to an
out of synchronization closure of a GF onto the system . Additionally, the Operator is responsible and
liable for any damage done to the FCU system by any type of improper closing onto the system .
1 . 6 Improper Operation of the GF
Operation and design of the GF must meet all the requirements contained in this document as well
as any applicable requirements contained in the Fort Collins Municipal Code and the Fort Collins
Utilities Electric Service Rules and Regulations and any written agreement between FCU and the
Operator. Also , no GF operation will at any time be allowed to adversely impact the operation of the
FCU system in any way. The GF must not produce adverse amounts of unbalanced currents or
voltages ; produce high or low voltages , or unacceptable frequencies ; it must not inject DC or
harmonics into the system beyond what is allowed by this document; or cause excessive operations
of system voltage regulating devices such as load tap changers and voltage regulators . The GF
must not adversely affect system grounding or ground fault protection .
FCU will not normally interfere with the operation of any GF . However, when requested by FCU by
telephone , in person , or in writing , the Operator must immediately stop operation and not resume
operation until cleared by FCU to do so . If the Operator begins to operate the GF out of the ranges
or conditions listed herein , the Operator must agree to cease operation until such a time as the GF
Operator can demonstrate to FCU that it has remedied the problem and can once again operate the
GF in compliance with these requirements .
If usage of the GF causes unusual fluctuations or disturbances on , or interference with FCU 's system
or other FCU customers , FCU shall have the right to require the GF to install suitable apparatus to
reasonably correct or limit such fluctuation , disturbance or interference at not expense to FCU or
other customers .
1 . 7 System Capacity Limitations
The equipment installed by FCU to distribute power is limited in size and is normally sized for safe
and efficient delivery of power. Adding generation to this system , especially generation supplied by
renewable sources which normally have low capacity factors , may quickly overload the existing
equipment. Care must be taken when adding generation to avoid damaging FCU equipment. Also ,
when system penetration levels of distributed generation becomes large enough , accidental
islanding of sections of the system becomes possible , and additional protective devices or systems ,
such as transfer trip equipment, may be needed for safe operation of the FCU system . Whenever
one or more of the following limitations are exceeded , FCU may need to conduct an additional study
and FCU may require additional equipment. Additional study is required if:
a ) The rated aggregate generation kVA on any distribution transformer after the addition of
the new GF equals or exceeds 100% of the rating of the transformer
b) The rated aggregate generation kVA on any protective device or feeder from the point of
interconnection to the substation transformer exceeds 13 . 3% of the rating of that
protective device or feeder
c) The rated aggregate generation kVA on any feeder or portion of a feeder equals or
exceeds 50% of the existing annual minimum load on that feeder or feeder section
Rev 8 . 0 January 2010 3
d ) The proposed GF results in more than 90kW of single-phase generation on one phase
of a feeder when both the new and existing generation are included
e) The proposed GF includes an induction machine 300kW or greater, or an aggregate of
300kW of induction generators
1 . 8 Submittal Requirement
The Operator shall submit in a timely manner, sufficient design and specification information relating
to the facilities to be installed by the Operator. FCU shall be entitled to review and approve or
disapprove these facilities prior to their installation and energization . The Operator agrees to
incorporate any reasonable design changes requested by FCU prior to , during , or after installation of
the GF 's facilities . FCU 's approval or acceptance of any design and specification information related
to the GF to be installed shall not be construed as an endorsement of such engineering plans ,
specifications , or other information .
The following drawings and other documents must be submitted to FCU for approval before any
construction is begun .
a ) Single-line diagram of the facility showing the sizes of all equipment and the system
protection planned
b) Cut sheets on all equipment planned including inverters , generators , fuses , circuit
breakers , switches , etc .
c) Capability curves on all synchronous and doubly fed induction generators .
d ) Short circuit calculations .
2 . 0 Standards and Definitions
2 . 1 Standards
In all cases the current edition of the following standards should be referred to in design of the power
plant, choice of equipment, and interconnection design .
a ) ANSI C84 . 1 American National Standard for Electric Power Systems and Equipment-
Voltage ratings (60 Hertz)
b) IEEE Std . 18 IEEE Standard for Shunt Capacitors
c) IEEE Std . 32 IEEE Standard Requirements , Terminology, and Test Procedures for
Neutral Grounding Devices
d ) IEEE Std . 141 : IEEE Recommended Practice for Electric Power Distribution for Industrial
Plants
e) IEEE Std . 142 : IEEE Recommended Practice for Grounding of Industrial and
Commercial Power Systems
f) IEEE Std . 242 : IEEE Recommended Practice for Protection and Coordination of
Industrial and Commercial Power Systems
g ) IEEE Std . 519 : Recommended Practices and Requirements for Harmonic Control in
Electric Power Systems
h ) IEEE Std . 665 : IEEE Standard for Generation Station Grounding
i ) IEEE Std . 1015 : IEEE Recommended Practice for Applying Low-Voltage Circuit
Breakers Used in Industrial and Commercial Power Systems
j ) IEEE Std . 1036 : IEEE Standard for Application of Shunt Power Capacitors
k) IEEE 1547 IEEE Standard for Interconnecting Distributed Resources with Electric Power
Systems
1 ) IEEE 1547 . 1 IEEE Standard Conformance Test Procedures for Equipment
Interconnecting Distributed Resources with Electric Power Systems
m ) IEEE 1547 . 2 IEEE Application Guide for IEEE Std . 1547 , IEEE Standard for
Interconnecting Distributed Resources with Electric Power Systems
n ) IEEE Std . C2 : National Electrical Safety Code
Rev 8 . 0 January 2010 4
o) IEEE Std . C37 . 06 : IEEE Standard for AC High-Voltage Circuit Breakers rated on a
Symmetrical Current Basis- Preferred Ratings and Required Capabilities .
p) IEEE C37 . 012 : IEEE Application Guide for Capacitor Current Switching for AC High-
Voltage Circuit Breakers
q ) IEEE C37 . 66 : IEEE Standard Requirements for Capacitor Switches for AC Systems
( 1 kV thru 38kV) .
r) IEEE C37 . 90 IEEE Standard for Relays and Relay Systems Associated with Electric
Power Apparatus
s ) IEEE C37 . 90 . 1 IEEE Standard for Surge Withstand capability (SWC ) Tests for Relay
and Relay Systems Associated with Electric Power Apparatus .
t) IEEE C37 . 90 .2 IEEE Standard for Withstand Capability of Relay Systems to Radiated
Electromagnetic Interference from Transceivers
u ) IEEE C37 . 90 . 3 IEEE Standard Electrostatic Discharge Tests for Protective Relays
v) IEEE C37 . 95 IEEE Guide for Protective Relaying of Utility-Consumer Interconnections
w) IEEE Std . C37 . 102 IEEE Guide for AC Generator Protection
x) IEEE Std C62 . 41 : IEEE Recommended Practice on Surge Voltages in Low-Voltage AC
Power Circuits
y) NERC PRC-024- 1 : Generator Frequency and Voltage Protective Relays
z) NFPA 70 : National Electrical Code
aa) UL 1741 : Inverters , Converters , Controllers and Interconnection System Equipment for
use with Distributed Energy Resources
2 .2 Definitions
The following definitions will be used throughout this document.
• ANSI -American National Standards Institute
• FCU-Fort Collins Utility Services
• GF-Generating facility
• IEEE- Institute of Electrical and Electronic Engineers
• KVA-Kilovolt-amps
• KW-Kilowatt
• MW-Megawatt
• NEC-National Electrical Code
• NEMA- National Electrical Manufacturers Association
• NESC-National Electrical Safety Code
• Operator-Generating facility owner and operator, successors , heirs , agents , employees , and
assigns
• PCC-Point of common coupling
• UL- Underwriters Laboratories
• VAR-Volt-Amps reactive ( reactive power)
3 . 0 GF Equipment and Installation Requirements
3 . 1 General Requirements
The installation of any GF shall meet the relevant requirements of the National Electrical Code ( NEC )
and the National Electrical Safety Code ( NESC ) . Where required by the municipality, the Operator
cleared to move forward with the installation must obtain all necessary building permits , pass all
applicable building department inspections , and meet other applicable requirements including but not
limited to municipal code and Fort Collins Electric Service Rules and Regulations .
Unless otherwise modified in this document, the interconnection must meet the requirements of IEEE
Std . 1547 . Where the requirements of this document vary from the requirements of IEEE Std . 15477
this document governs .
Rev 8 . 0 January 2010 5
The Operator shall be solely responsible for protecting the GF and all associated equipment from
abnormal distribution system conditions such as outages , short circuits , voltage or frequency
variations , or other disturbances . FCU will not install equipment for the protection of the GF
generator or other equipment . The GF equipment must be designed and operated so that it is
capable of properly synchronizing the generator to the system , maintaining safe operation of the
generation equipment, detecting any unusual operating condition , and disconnecting the generator
from the system anytime damage to the generator or other equipment may occur. The equipment
protection provided by the Operator will prevent the GF from adversely affecting the distribution
system's capability of providing reliable service to other FCU customers . The GF must automatically
disconnect itself from the system anytime system conditions are outside the ranges described in this
document and is not permitted to reconnect to the system until system conditions return to normal
and are maintained within the normal range for a minimum of five (5) minutes .
3 .2 Interconnection Disconnect Switch
Each GF installation must include a manually operated , lockable , disconnect switch with a visual
break. The disconnect switch must be visible and accessible at all times by FCU personnel to allow
the GF to be disconnected safely during maintenance or outage conditions . In the case of a PV
system this disconnect switch must be located next to the FCU electric meter. In all cases the
disconnect switch must be rated to interrupt the maximum output of the generator and must be rated
for the voltage and fault current requirements of the GF and must meet all applicable NEMA, UL ,
ANSI , IEEE , and NEC standards as well as local and state electrical codes . The disconnect switch
shall be permanently labeled with text indicating that the switch is for the GF . The labeling shall also
clearly indicate the open and closed position of the switch . The disconnect switch must be located on
the output or load side of the GF such that the entire GF can be isolated from FCU distribution
system . If the site contains several generators , a single disconnect switch may be used providing its
rating is sufficient for all generators and opening it produces a visible open point between all
generators and the FCU system .
Other devices such as circuit breakers or fuses may be considered as a substitute for a disconnect
switch if each of the following conditions is met:
a ) If a circuit breaker is used it is draw-out and capable of being locked into the
disconnected position
b) If a fuse is used it is capable of being removed from the bus to provide a visual open
point
c) The Operator or Operator's agents are available at all times to disconnect and remove
this breaker or fuses whenever requested by FCU
All lock-out and tag-out capabilities must also be available for the devices used and must be
assessable to FCU personnel .
3 . 3 Dedicated Transformer and Additional Primary Protection
If the GF rating is greater than 50kW the GF must be connected to the FCU by a dedicated
transformer. The transformer must meet FCU standards and design criteria . The transformer must
be labeled according to FCU practices .
Most interconnecting transformers on the FCU system are protected with fuses . However, if a GF is
rated at 1500 kVA or above , FCU may determine the fuse protection is insufficient to properly protect
the FCU system . In this case , FCU may require that a dedicated three-phase interrupting device
such as a recloser must be added to the transformer high-voltage side along with necessary
relaying . . Moreover, any GF whose connection to the FCU distribution system increases the
aggregate generation on any feeder, transformer, or portion of a feeder to 1500 kVA or above is
subject to a separate study by FCU , and FCU may require the addition of a three-phase protective
device on the primary side of the system .
Rev 8 . 0 January 2010 6
3 .4 Interrupting Devices Required
Circuit breakers or other interrupting devices located at the Point of Common Coupling ( PCC ) must
be certified or " Listed" (as defined in Article 100 , the Definitions Section of the National Electrical
Code ) as suitable for their intended application . This includes being capable of interrupting the
maximum available fault current expected at their location . The Operator' s GF Facility and
associated interconnection equipment must be designed so that the failure of any single device will
not potentially compromise the safety and reliability of FCU 's distribution system .
3 . 5 System Protective Functions
The protective functions and requirements contained in this document are designed to protect FCU ' s
distribution system and not specifically the Operator's GF . The Operator is solely responsible for
providing adequate protection for the GF and all associated equipment. The Operator's protective
devices must not impact the operation of other protective devices utilized on the FCU distribution
system in a manner that would affect FCU 's ability to provide reliable service to its customers .
The GF's protective functions must sense abnormal conditions and disconnect the GF from the FCU
distribution system during abnormal conditions . All GFs must be capable of sensing line-line-line ,
line-line , and line-ground faults on the distribution feeder supplying the GF and must disconnect from
the line to protect both the line from further damage and the generator from damage due to
excessive currents or unusual voltages . The settings of these relays will be coordinated with FCU
substation relaying .
For induction machines speed matching must be done automatically and shall match speed to less
that 5 % before closing the associated breaker.
The minimum protective functions needed for various types of generators , and other requirements
for system protection are shown below. Any machine that is not included in one of the following
categories must be individually considered by FCU .
3 . 5. 1 Synchronous Machines above 50kW to 100kW
a ) Over and under voltage functions (27/59 )
b) Over current trip functions . (50/51 ) which may be included in a breaker trip-unit or a
fuse .
c) Ground fault protection (50/51 G )
d ) Over and under frequency functions . (81 O/U )
e) Sync Check (25 )
f) Phase-sequence or negative sequence voltage (47)
g ) A function to prevent the GF from contributing to the formation of an unintended island
and to prevent the GF from reconnecting with the distribution system under abnormal
conditions is required .
h ) Relay settings and test reports will be submitted to FCU for review. FCU will determine
if an on-site inspection is required .
3 . 5.2 Synchronous Machines 100kW to and including 1000kW
a ) Interrupting devices must be 3- phase circuit breakers with electrical operation .
b) Relays must be utility grade ( must meet IEEE Std . C37 . 90 , C37 . 91 , C37 . 92 and C37 . 93 )
and must be independent from the generator control devices .
c) Over and under voltage functions (27/59 )
d ) Voltage restrained over current trip functions . (50/51V)
e) Ground fault protection (50/51 G )
f) Over and under frequency functions . (81 O/U )
g ) Sync Check (25 )
h ) Phase-sequence or negative sequence voltage (47)
Rev 8 . 0 January 2010 7
i ) Reverse power (32 )
j ) A function to prevent the GF from contributing to the formation of an unintended island
and to prevent the GF from reconnecting with the distribution system under abnormal
conditions is required .
k) Relay settings and test reports will be submitted to FCU for review. FCU will determine if
an on-site inspection is required .
3 . 5. 3 Synchronous Machines 1000kW to and including 500011kW
a ) Interrupting devices must be 3- phase circuit breakers with electrical operation .
b) Relays must be utility grade ( must meet IEEE Std . C37 . 90 , C37 . 91 , C37 . 92 and C37 . 93 )
and must be independent from the generator control devices .
c) Over and under voltage functions (27/59 )
d ) Voltage restrained over current trip functions . (50/51V)
e) Ground fault protection (50/51 G )
f) Over and under frequency functions . (81 O/U )
g ) Negative Sequence Current (46 )
h ) Loss of Field (40 )
i ) Sync Check (25 )
j ) Phase-sequence or negative sequence voltage (47)
k) Reverse power (32 )
1 ) A function to prevent the GF from contributing to the formation of an unintended island
and to prevent the GF from reconnecting with the distribution system under abnormal
conditions is required .
m ) Relay settings and test reports will be submitted to FCU for review.
3 . 5.4 Doubly-Fed Induction Machines above 50kW to 100kW
a ) Over and under voltage functions (27/59 )
b) Over current trip functions . (50/51 ) which may be included in a breaker trip-unit or a
fuse .
c) Ground fault protection (50/51 G ) which may be included in a breaker trip-unit or a fuse
d ) Phase-sequence or negative sequence voltage (47)
e) Speed matching to within 5% ( 15 )
f) If it is determined that it is possible for the machine to self-excite in this installation , the
GF must include a function to prevent the GF from contributing to the formation of an
unintended island and to prevent the GF from reconnecting with the distribution system
under abnormal conditions . If it is determined that the machine cannot self-excite ,
evidence must be provided to FCU proving that this is the case and anti-islanding
protection is not required . If such evidence does not meet FCU approval , anti-islanding
protection is required .
g ) Relay settings and test reports must be submitted to FCU for review. FCU will
determine if an on-site inspection is required .
3 . 5. 5 Doubly-Fed Induction Machines 100kW to 5000kW
a ) Interrupting devices must be 3- phase circuit breakers with electrical operation .
b) Relays must be utility grade ( must meet IEEE Std . C37 . 90 , C37 . 91 , C37 . 92 and C37 . 93 )
and must be independent from the generator control devices .
c) Over and under voltage functions (27/59 )
d ) Over current trip functions . (50/51 ) which may be included in a breaker trip-unit or a
fuse .
e) Ground fault protection (50/51 G ) which may be included in a breaker trip-unit or a fuse
f) Phase-sequence or negative sequence voltage (47)
g ) Negative sequence current (46 )
h ) Over and under frequency (81 O/U )
i ) Reverse power (32 )
j ) Speed matching to within 5% ( 15 )
Rev 8 . 0 January 2010 8
k) If it is determined that it is possible for the machine to self-excite in this installation the
GF must include a function to prevent the GF from contributing to the formation of an
unintended island and to prevent the GF from reconnecting with the distribution system
under abnormal conditions . If it is determined that the machine cannot self-excite ,
evidence must be provided to FCU proving that this is the case and anti- islanding
protection is not required . If such evidence does not meet FCU approval , anti-islanding
protection is required .
I ) Relay settings and test reports must be submitted to FCU for review. FCU will
determine if an on-site inspection is required .
3 . 5.6 Induction Machines above 50kW to 100kW
a ) Over and under voltage functions (27/59)
b) Over current trip functions . (50/51 ) which may be included in a breaker trip-unit or a
fuse .
c) Ground fault protection (50/51 G ) which may be included in a breaker trip-unit or a fuse
d ) Phase-sequence or negative sequence voltage (47)
e) Speed matching to within 5% ( 15 )
f) If it is determined that it is possible for the machine to self-excite in this installation the
GF must include a function to detect and trip the unit during a self excited condition . This
will prevent system over voltages and also prevent the GF from contributing to the
formation of an unintended island . If it is determined that the machine cannot self-excite ,
evidence must be provided to FCU proving that this is the case and this protection is not
required . If such evidence does not meet FCU approval , anti-islanding protection is
required .
g ) Relay settings and test reports must be submitted to FCU for approval . FCU will
determine if an on-site inspection is required .
3 . 5.7 Induction Machines 100kW to 5000kW
a ) Interrupting devices must be 3- phase circuit breakers with electrical operation .
b) Relays must be utility grade ( must meet IEEE Std . C37 . 90 , C37 . 91 , C37 . 92 and C37 . 93 )
and must be independent from the generator control devices .
c) Over and under voltage functions (27/59 )
d ) Over current trip functions . (50/51 ) which may be included in a breaker trip-unit or a
fuse .
e) Ground fault protection (50/51 G ) which may be included in a breaker trip-unit or a fuse
f) Phase-sequence or negative sequence voltage (47)
g ) Negative sequence current (46 )
h ) Over and under frequency (81 O/U )
i ) Reverse power (32 )
j ) Speed matching to within 5% ( 15 )
k) If it is determined that it is possible for the machine to self-excite in this installation the
GF must include a function to detect and trip the unit during a self excited condition . This
will prevent system over voltages and also prevent the GF from contributing to the
formation of an unintended island . If it is determined that the machine cannot self-excite ,
evidence must be provided to FCU proving that this is the case and this protection is not
required . If such evidence does not meet FCU approval , anti-islanding protection is
required .
1 ) Relay settings and test reports will be submitted to FCU for review. FCU will determine
if an on-site inspection is required .
3 . 5.8 Inverter Connected Systems 1000 kW and Below
This may include photovoltaic systems ( PV) , some wind turbines , fuel cells , microturbines
and all other machines that deliver their power to the utility system via an inverter or
converter utilizing power electronics .
Rev 8 . 0 January 2010 9
a ) The Inverter must be tested to meet IEEE 15477 and IEEE 1547 . 1 . One way to meet this
requirement is to be tested to UL1741 . However, it is not required that this testing be
done by Underwriters Laboratories . Any recognized testing lab which confirms that the
inverter meets IEEE 1547 , and IEEE 1547 . 1 is satisfactory. If the inverter does not carry
a UL sticker, FCU must be supplied with a letter from the manufacturer or an
independent testing laboratory stating the inverter has been tested and meets the above
IEEE standards .
b) FCU will require over current trip functions (50/51 ) which may be included in a breaker
trip-unit or a fuse . This device must be separate from the inverter control system and
internal disconnect device .
c) FCU will determine if an on-site inspection is required to observe calibration and testing
of the inverter functions .
3 . 5.9 Inverter Connected Systems above 1000 kW to 5000kW
This may include photovoltaic systems ( PV) some wind turbines , fuel cells , microturbines
and all other machines that deliver their power to the utility system via an inverter or
converter utilizing power electronics .
a ) The Inverter must be tested to meet IEEE 1547 , and IEEE 1547 . 1 . One way to meet this
requirement is to be tested to UL1741 . However, it is not required that this testing be
done by Underwriters Laboratories . Any recognized testing lab which confirms that the
inverter meets IEEE 1547 , and IEEE 1547 . 1 is satisfactory. If the inverter does not carry
a UL sticker, FCU must be supplied with a letter from the manufacturer or an
independent testing laboratory stating the inverter has been tested and meets the above
IEEE standards .
b) FCU will require over current trip functions (50/51 ) which may be included in a breaker
trip-unit or a fuse . This device must be separate from the inverter control system and
internal disconnect device .
c) Ground fault protection (50/51G ) which may be included in a breaker trip unit. This
device must be separate from the inverter control system and internal disconnect device .
d ) Over and under frequency (81 O/U ) . This device must be separate from the inverter
control system and internal disconnect device .
e) Over and under voltage functions (27/59 ) . This device must be separate from the
inverter control system and internal disconnect device .
f) FCU will determine if an on -site inspection is required to observe calibration and testing
of the inverter and relay functions .
3 . 5. 10 All machines above 5000kW
Any type of GF of this size must be studied and considered individually by FCU .
3 . 6 Momentary Paralleling Generation Facilities
At times an Operator may decide to install a system that may operate parallel to the FCU system
only momentarily ( normally less than 0 . 1 seconds) . With FCU 's approval , the transfer switch or
system used to transfer the Operator' s loads from FCU ' s distribution system to the Operator' s GF
may be used in lieu of the protective functions required for parallel operation .
4. 0 Facility Grounding
In all cases the GF grounding system must not adversely impact FCU grounding or ground fault protective
relaying . The GF grounding must not cause high voltages to occur under any condition either normally
occurring or occurring during a system fault such as allowing high voltages to exist on the un-faulted phases
during a single-line-to-ground fault.
Rev 8 . 0 January 2010 10
4. 1 Equipment Bonding Conductor
The Operator must install an equipment-grounding conductor, in addition to the ungrounded
conductors and grounded conductor (neutral ) , between the GF and the distribution system . The
grounding conductor must be permanent, electrically continuous , and must be capable of safely
carrying the maximum fault current that could be imposed it by the systems to which it is
connected . Additionally, the equipment-grounding conductor must be of sufficiently low impedance to
facilitate the operation of over current protection devices under fault conditions . All conductors shall
comply with the National Electrical Code ( NEC ) . The GF must not be designed or implemented such
that the earth becomes the sole fault current path .
4.2 Surge Protection
It is strongly recommended but not required that a surge protective device (SPD ) be utilized to
protect GF equipment.
4. 3 System Grounding
FCU maintains an effectively grounded distribution system and requires that all GFs be designed to
contribute to an effectively grounded system . Effective grounding prevents the occurrence of
excessively high voltages during ground faults and protects existing FCU equipment. Effective
grounding of the GF may desensitize existing FCU ground fault protection , which could require FCU
ground fault relay settings changes or modifications in the design of the GF . The transformer
supplied to interconnect the GF voltage to the FCU system will normally be a grounded -wye to
grounded-wye transformer. This connection will not provide a grounding source by itself and will not
provide an effectively grounded system from the GF side of the interconnection unless effective
grounding of GF is provided . When designing the grounding system for the GF , the designer should
consider the condition that will result when a ground fault occurs on the line serving the GF . This
ground fault would be cleared on the FCU side of the line by opening a breaker or recloser in the
FCU substation . This will result in momentarily islanding the line on the GF until it opens its breaker.
Under this condition , where the line is islanded and being supplied by the GF , the system must
remain effectively grounded .
Effective grounding shall be defined by IEEE Std . 142 which states that to be considered effectively
grounded both of the following two conditions must be met:
a ) The ratio of zero-sequence reactance to positive-sequence reactance (Xo/Xl ) must be
positive and three or less .
b) The ratio of zero-sequence resistance to positive-sequence reactance ( Ro/Xl ) must be
positive and less than 1 .
The GF system equivalent (Thevenin equivalent) impedance must meet the criteria for effective
grounding stated above . The networks used in determining this impedance , and other fault current
calculations for the plant, will include the positive , negative , and zero sequence networks of the step-
up transformer connected to the FCU system , all other transformers between the generator and the
point of common coupling , the generator subtransient, positive , negative and zero sequence values ,
the neutral grounding device for the generator, the grounding transformer and neutral grounding
device ( if used ) and any significant cable runs . The GF shall maintain an effectively grounded
system under normal operating conditions while operating in connection with FCU lines .
The short circuit contribution ratio (SCCR) of the GF is defined as the ratio of the GF short circuit
contribution to FCU ' s contribution to a short circuit ( IScGF/IscFCU ) for either a three-phase or single-
line-to ground fault measured at the high voltage side of the transformer stepping up from the
generation voltage to the FCU voltage .
The GF must be grounded in such a way that the SCCR for a line-ground fault calculated at the high
voltage side of the transformer connecting the GF to FCU is less than 3% while still achieving
effective grounding as defined above . If this SCCR ratio is greater than 3 % FCU must do a study to
Rev 8 . 0 January 2010 11
determine if re-setting ground fault relays on the existing FCU system is required . In rare cases
connecting a certain GF to a particular feeder may not be practical due to protection issues or
special protection techniques may be needed to make the connection safe .
Proper grounding of the GF can be achieved in a number of ways . FCU may at its discretion accept
any of the following methods :
a ) Solidly grounding the generator or installing a solidly grounded grounding transformer
(zig-zag or grounded wye-delta transformer) . While a solidly grounded generator is
acceptable to FCU if all other requirements are met, it must be used with care . ANSI
standards generally require that for a synchronous generator the ground fault current
must be limited to the three- phase fault current. This usually requires a resistance or
reactance be used for grounding the generator neutral . Also , a solidly grounded
generator may conduct large amounts of harmonic currents . There may be some
unbalanced voltage at the terminals of the generator. This can cause circulating current
through the generator if it is solidly grounded which may make de-rating of the generator
necessary . If a solidly grounded system is used the designer must consider and plan for
all issues that may result.
b) Resistance grounding . A resistance grounded generator or grounding transformer with
a resistance placed between neutral and ground may be used if it meets the
requirements of effective grounding .
c) Reactance grounding . A reactance grounded generator or grounding transformer with a
reactor between the transformer neutral and ground may be used if it meets the
requirements of effective grounding .
d ) Other methods may be suggested for consideration by FCU .
If the Operator desires to generate at the FCU primary voltage and to connect the generators directly
to the FCU system without the use of an interconnecting transformer, FCU must first conduct a study
of the connection . FCU will determine , as a result of the study, the grounding and other
requirements necessary for this type of connection .
5. 0 Prevention of Interference and Unacceptable Operating Conditions
The Operator must not operate the GF in any way that causes a system disturbance or that superimposes a
voltage or current upon FCU ' s distribution system that results in interference with FCU operations , service to
FCU 's customers , or other FCU equipment and facilities . When FCU suspects that interference with electric
service to other FCU customers is occurring , and such interference exceeds FCU Standards , FCU reserves
the right at its expense to install special test equipment as may be required to perform a disturbance analysis
and monitor the operation of the GF to evaluate the quality of power produced . If the GF is demonstrated to
be the source of the interference , and it is demonstrated that the interference produced exceeds FCU
Standards or generally accepted industry standards , FCU may, without liability, disconnect the GF from the
FCU distribution system . lt shall be the responsibility of the Operator to eliminate any interference caused by
the GF and the Operator must diligently pursue and take corrective action , at the Operator' s own expense , to
eliminate undesirable interference caused by the GF . The GF will be reconnected to the FCU system only
after the Operator demonstrates to the satisfaction of FCU that the cause of the interference has been
remedied .
The Operator's protective devices must prevent the GFs from contributing to an island . If the FCU feeder to
which the GF is connected is de-energized for any reason , the GF must sense this and disconnect itself
within 2 seconds of the de-energization of the feeder.
Rev 8 . 0 January 2010 12
5. 1 Voltage Regulation
The GF shall not actively regulate the voltage at the point of common coupling ( PCC ) unless the
effects of this are first reviewed and approved by FCU . If a study has been done by FCU which
determines that it is advantageous for a GF to actively control its voltage , FCU will inform the
Operator and the Operator will be required to control the GF's terminal voltage .
5.2 System Voltage
The voltage operating range limits for GFs shall be used as a protection function that responds to
abnormal conditions on FCU ' s distribution system . The FCU voltage operating range is normally -
95% to 105% of the nominal voltage at the electrical service point, and 92% to 105 % of nominal
voltage at the utilization point, as required by ANSI C84 . 1 . All GFs must be capable of operating
within the voltage range normally experienced on FCU 's distribution system . Ocassional excursions
outside this range may occur, and tripping of the GF is not suggested until the voltage range is less
than 88% or more than 110% of the nominal voltage . The operating range and GF protection shall be
selected in a manner that minimizes nuisance tripping between 88% and 110% of nominal voltage .
GFs must not energize or, after a trip , re-energize FCU ' s circuits whenever the voltage at the PCC
deviates from the allowable voltage operating range allowed by ANSI C84 . 1 Table 1 voltage range
(95- 105% of nominal voltage at the service or 92- 105% of nominal voltage at the utilization point) .
Whenever the FCU distribution system voltage at the PCC varies from normal ( nominally 120 volts)
by the amounts as set forth in Table 5- 1 the GF' s protective functions shall disconnect the
generator(s) from the FCU distribution system with delay times no longer than those shown .
Table 5-1 : Voltage trip settings .
(Adapted from IEEE 1547-2003 and ANSI C84. 1 -2006)
Voltage at Point of Common Maximum Tripping Time Delay
Coupling (% of base Voltage) (seconds/cycles )
V-PCC < 50% 0 , 16 / 10
50% < V-PCC < 88% 2 . 0 / 120
92% < V-PCC < / 105% Normal operating range
110% < V-PCC < 120% 1 . 0 / 60
120 % < V-PCC 0 , 16 / 10
5. 3 System Frequency
The GF shall operate in synchronism with the FCU distribution system . Whenever FCU ' s distribution
system frequency at the PCC varies from normal (nominally 60 Hertz) by the amounts as set forth in
Table 5-2 the GF's protective functions shall disconnect the generator(s) from the FCU distribution
system with delay times no longer than those shown .
Table 5-2 : Frequency Settings
(Adapted from IEEE 1547-2003 and NERC PRC -024-1 )
GF Facility Size Frequency ( Hz) Maximum Tripping Time
Delay
(sec ./cycles)
GF 30kW or Less GF< 59 . 3 0 , 16/10
59, 35 GF <_ 60 . 5 Continuous Operation
GF> 60 . 5 0 , 16/10
GF > 30kW
GF< 57 . 8 0 , 16/10
57 , 85 GF <_ 58 . 0 4/240
58 . 0 < GF <_ 58 . 5 40/2 ,400
58 . 5 < GF <_ 59 .0 200/12 ,000
Rev 8 . 0 January 2010 13
59 . 0 < GF < 59 .5 19800/1089000
59 , 55 GF <_ 60 . 5 Continuous Operation
60 . 5 < GF <_ 61 . 5 600/369000
61 .5 < GF 0 , 16/10
Unless some other anti- islanding scheme is employed , the GF should disconnect due to low
frequency resulting from islanding the feeder load on the GF . The frequency settings must be
adjusted to insure that, during the lowest loading level on the feeder, the resulting frequency change
of the GF when it is islanded with those feeder loads , should cause the under frequency relaying to
disconnect the the generators within two seconds .
5.4 Synchronization
Synchronous machine automatic synchronizers and sync-check relays must be set as shown in
Table 5-3 .
Table 5-3 : Synchronizer/sync check relay settings .
(Adapted from IEEE 1547-2003)
Rating of GF (kVA) Maximum Slip Rate Maximum Voltage Maximum Phase
( Hz) Difference (%V) Angle Difference
(deg ) .
0-500 0 . 3 10 20
500- 1500 0 . 2 5 10
1500 and above 0 . 1 3 10
5. 5 Flicker
Any voltage flicker at the PCC caused by the GF should not exceed the limits defined by the
" Maximum Borderline of Irritation Curve" identified in IEEE 519 , IEEE 141 , and IEE 1453 . This limit
is shown in Figure 5- 1 . This requirement is necessary to minimize the adverse voltage effects which
may be experienced by other customers on the FCU distribution system due to the operation of the
GF . Induction generators may only be connected to the system and brought up to synchronous
speed (as an induction motor) if these flicker limits are not exceeded .
Rev 8 . 0 January 2010 14
6
5
a 4
0
w
C7
3
J
O wBORDERLINE OF IRRITATION
z 2 BORDERLINE OF VISIBILITY OF FLICKER
w
U
Q
w
a 1
0 1 2 5 10 20 30 1 2 5 10 20 30 1 2 5 10 20
DIPS PER HOUR DIPS PER MINUTE DIPS PER SECOND
FREQUENCY OF DIPS
30 12 6 3 2 1 30 12 6 3 2 1 .3 2 1 05
MINUTES SECONDS
TIME BETWEEN DIPS
Figure 5-1 : Allowable voltage flicker vs . time ( reproduced from IEEE Std , 141 ) ,
5. 6 Harmonics
Harmonic distortion measured at the PCC must be in compliance with IEEE 519 and IEEE 1547 .
Harmonic current injection limits are shown in Table 5-4 .
Table 5-4 : Maximum harmonic current distortion as a percentage of fundamental
frequency at the point of common coupling .
(Adapted from IEEE 1547-2003)
Individual Harmonic Order h (Odd Harmonics Only)
h < 11 115h < 17 175h <23 235h < 35 355h TDD
4 . 0 2 . 0 1 . 5 0 . 6 0 . 3 5 . 0
The even harmonic limits must be 25 % of those shown in Table 5-4 .
GF ' s must not inject direct current greater than 0 . 5% of rated output into the FCU distribution system .
Any device causing a DC offset such as a half-wave converter shall not be allowed .
5. 7 Power Factor
The power factor at the point of common coupling ( PCC ) with FCU (the low voltage terminals of the
transformer connecting the GF to FCU ) shall always remain within 0 . 95 lagging (VARs going into the
site ) to 0 . 95 leading (Vars going out of the site ) . The only exception to this requirement is a GF
consisting of an inverter connected generator 10 kW or less . For this exception it is expected that
the site power factor will deteriorate anytime the GF is operating , and FCU will provide the VARs
needed at the site . However the site power factor must be maintained such that it would remain
within the limits stated above if the GF was not operating and , as a result, the power factor was
allowed to revert to the value it had before the GF was added .
Rev 8 . 0 January 2010 15
a )
Each synchronous generator in a GF shall be capable of operating at any point within a power factor
range of 0 . 95 leading (Vars going into the generator) to 0 . 95 lagging (Vars going out of the
generator) . Synchronous generators should automatically control power factor and should be set to
deliver VARs to the system as needed to keep the power factor at the PCC with FCU to the range
required by this section .
For generators other than synchronous generators , operation outside this power factor range is
acceptable provided the cumulative power factor of the customer' s entire facility is kept within the
range noted . This may be done using capacitor banks , controlling the inverter settings , adding static
VAR compensators (SVC ) or synchronous condensers , or other means agreeable to both the GF
and FCU . If capacitor banks are used they shall be sized and installed per IEEE Stds . 18 , 1036 ,
C37 . 0127 C37 . 06 , C37 . 66 , and 1015 . Capacitors may need to be stepped and switched to meet the
power factor requirements above . Before the addition of capacitors the GF should completely study
the effects of the capacitor additions on the resonance conditions and harmonic values that will
result. If the GF ' s addition of capacitors causes adverse resonance or harmonics effects on FCU ' s
system , the GF shall be required to pay for any modifications needed to mitigate the problem .
6. 0 Monitoring Provisions
The following monitoring and metering requirements must be met by any Operator connecting a GF to the
FCU system .
6. 1 Metering
GFs larger than 10kW and less than or equal to 100 kW require a minimum of a form 9s metering
installation .
GFs larger than 100 kW will require revenue metering capable of recording the following
components :
a ) Time of use (TOU )
b) Harmonic measuring capability
c) Four quadrant capability
d ) MV90 capable
e) Form 9S
f) The revenue meter must measure the aggregate load of the Operator's facility including
the GF .
6.2 Monitoring and Control Requirements
Each non-inverter connected generating facility of 100 kW or larger shall be required , at the
discretion of FCU , to have FCU supplied equipment that will be used for monitoring and control of
the facility. The Operator shall be responsible for all hardware , software , and any installation costs
of FCU provided equipment associated with the co-gen installation . FCU will provide a remote
monitoring and control equipment enclosure containing the following equipment at the Operator' s
expense :
• 900 MHZ spread spectrum radio
• SEL 351 relay
• Terminal blocks as required
• Various control switches , CT blocks , etc as required
Rev 8 . 0 January 2010 16
• UPS power supply with battery backup
A YAGI antenna will be provided and shall be installed by the Operator at a location designated by
FCU . The Operator will be responsible for installing the antenna coax specified by FCU . The
Operator must use a certified installer to terminate the coax . The Operator shall also be responsible
for mounting the equipment enclosure .
The monitoring and control system shall be designed to allow FCU to perform the following :
• Trip the generator breaker for unstable system conditions such as frequency, voltage
and fault conditions
• Place a HOT LINE TAG on the generator breaker that would block its close circuit to
prevent its closing
• Initiate a generator startup thru SCADA for future power dispatching by FCU (This would
normally be blocked locally unless requested by the Operator. )
• Monitor the generator breaker status to determine if the generator is on or off line
• Monitor generator output power( real and reactive ) , voltage , harmonics etc . (This will
require current and voltage inputs from the GF equipment. )
The GF Operator must provide all the necessary interface design to accomplish the functions listed
above . The GF Operator must submit drawings of the proposed design to FCU for review.
7. 0 Testing
7 . 1 Commissioning Tests
In addition to any commissioning tests required by the owner of the GF or manufacturer of
equipment used , the following tests must be performed before operation of the GF . The Operator
must notify FCU two weeks in advance of the time of the testing so that a FCU representative may
observe any tests required by FCU .
a ) Visual inspection to ensure proper grounding .
b) Visual inspection shall confirm the presence of the isolation device described in section
3 . 2 and the device shall be tested for operation .
c) Trip tests must be performed to prove each device which is required to trip any breaker
is capable of doing so .
d ) Relays or protective functions provided by the generator manufacture must be tested
and relay test reports must be made available to FCU . All of the functions required in
Section 3 . 5 must be tested . Inverter connected devices tested by an independent
testing laboratory as required in Section 3 . 5 are not be required to perform this test.
e) In the case of a synchronous generator the Operator must prove that the generator is
connected to the system with the proper phase rotation and that all three phases of
generator voltage match those of the system at the same instant in time . This test is
commonly known as " phasing out" the generator.
f) In the case of a synchronous generator the Operator must prove that the generator
synchronizer and sync check relay is capable of connecting the generator to the system
properly and in synchronism . This test must be done before the generator is allowed to
actually connect to the system .
g ) The ability of the control system to disconnect the generator within two seconds in the
event of islanding must be tested .
7 .2 Periodic Maintenance Tests
An Operator must maintain his or her equipment in good order and in compliance with all
manufacturers suggested periodic maintenance . If it is discovered that an Operator is not properly
maintaining his or her equipment, FCU may disconnect the GF until such time that the Operator can
prove that he or she has provided all required maintenance needed to allow the GF to operate
properly and safely .
Rev 8 . 0 January 2010 17
FCU reserves the right to inspect the GF equipment whenever it appears the GF is operating in a
manner that is hazardous to the FCU system .
Functional testing must be performed every year to prove the proper operation of the isolation device
and all breakers and relays . For all GFs consisting of synchronous machines with aggregate ratings
of larger than 1000kW, no less than once every three years all protective functions must be re-tested
and calibrated to prove their operation complies with the requirements contained in this document.
The Operator must maintain written records of these tests and these records will be made available
to FCU on request.
Battery systems used for generator control or protective relaying must be maintained and periodically
tested as suggested by the battery manufacturer.
7 . 3 Qualified Personnel
All testing and calibration shall be done by qualified personnel . FCU will provide a list of contractors
qualified to provide this service .
8 . 0 Design Changes
After the GF begins operation any design changes , such as the addition of more generation , must be
submitted to FCU for review. Protective devices or any other requirements listed in this document
must not be modified or their settings changed without approval of FCU .
9. 0 Liability and Insurance
In no event shall FCU be held responsible for the safety , reliability, design , or protection of the GF .
Compliance with these interconnection standards does not mean the GF is safe to operate and the
Operator is solely responsible for making a determination about whether the GF is safe to operate .
Nothing herein shall be construed to create any duty to , any standard of care with reference to , or
any liability to any person who is not a party to an arrangement or agreement between FCU and the
Operator pursuant to these requirements . FCU is not liable for damages caused to the facilities ,
improvements or equipment of the Operator by reason of the operation , faulty operation or non-
operation of FCU facilities .
The Operator shall be solely responsible for and shall defend , indemnify and hold FCU harmless
from and against any and all claims or causes of action for personal injury, death , property damage ,
loss or violation of governmental laws , regulations or orders , which injury , death , damage , loss or
violations occurs on or is caused by operation of equipment or facilities on the Operator's side of the
point of connection . Notwithstanding the above , the Operator shall be solely responsible for and shall
defend , indemnify and hold harmless FCU from and against any and all claims or causes of action
for personal injury , death , property damage or loss or violation of governmental laws , regulations or
orders , wherever occurring , which injury , death , damage , loss or violation is due solely to the acts of
omissions of such Operator, including but not limited to the use of defective equipment or faulty
installation or maintenance or equipment by such party. However, nothing contained in this section
shall be construed as relieving or releasing either party from liability or personal injury, death ,
property damage or loss , or violation of governmental laws , regulations or orders , wherever
occurring , resulting from its own negligence or the negligence of any of its officers , servants , agents
or employees . In the event of concurrent negligence , liability shall be apportioned between the
parties according to each party's respective fault. Neither the Operator nor FCU shall be liable to the
other or any other third party, in contract or in tort or otherwise , for loss of use of equipment and
related expenses , expense involving cost of capital , claims of customers of FCU or the Operator, as
Rev 8 . 0 January 2010 18
applicable , loss of profits or revenues , cost of purchase or replacement power, or any indirect ,
incidental or consequential loss or damage whatsoever.
The Operator shall pay all costs that may be incurred by FCU in enforcing the indemnity described
herein . Each party's liability to the other party for any loss , cost, claim , injury , liability, or expense ,
including reasonable attorney's fees , relating to or arising from any act or omission in its
performance of this agreement, shall be limited to the amount of direct damage actually incurred . In
no event shall either party be liable to the other party for any indirect, incidental , special ,
consequential , or punitive damages of any kind whatsoever.
For systems of ten kW or more , the Operator, at its own expense , shall secure and maintain in effect
during connection of its GF to the FCU system , liability insurance with a combined single limit for
bodily injury and property damage of not less than $300 , 000 (Three Hundred Thousand Dollars )
each occurrence . Such liability insurance shall not exclude coverage for any incident related to the
subject GF or its operation . FCU shall be named as an additional insured under the liability policy.
For systems above 500 kW and up to one megawatt, the Operator, at its own expense , shall secure
and maintain in effect during connection of its GC to the FCU system , liability insurance with a
combined single limit for bodily injury and property damage of not less than $2 , 000 , 000 (Two Million
Dollars ) for each occurrence . Insurance coverage for systems greater than one megawatt shall be
determined on a case-by-case basis by FCU and shall reflect the size of the installation and the
potential for system damage . Any insurance policy required herein shall include that written notice
be given to FCU at least 30 days prior to any cancellation or reduction of any coverage . Such
liability insurance shall provide , by endorsement to the policy, that FCU shall not by reason of its
inclusion as an additional insured incur liability to the insurance carrier for the payment of premium of
such insurance . A copy of the liability insurance certificate must be received by FCU prior to GF
operation . Certificates of insurance evidencing the requisite coverage and provision (s ) shall be
furnished to FCU prior to date of interconnection of the generation system . FCU shall be permitted
to periodically obtain proof of current insurance coverage from the Operator in order to verify proper
liability insurance coverage . The Operator will not be allowed to commence or continue
interconnected operations unless evidence is provided that satisfactory insurance coverage is in
effect at all times .
Rev 8 . 0 January 2010 19
APPENDIX A-TYPICAL ONE - LINE INDUCTION GENERATOR BETWEEN 50KW AND 100KW
13 . 8KV LINE ow TO OTHER LOADS
FUSE
UTILITY TRANSFORMER
POINT OF COMMON COUPLING
CUSTOMER CUSTOMER CUSTOMER
GF METER GF METER GF METER T
M RT
OTHER OTHER
CUSTOMER CUSTOMER
LOADS LOADS
CUSTOMER
SERVICE
PANEL
LOCKABLE
ACCESSABLE
DISCONNECT
SWITCH
GROUNDING TRANSFORMER
FOR 3 — PHASE MACHINES
F —1 PROTECTIVE FUNCTIONS
27 UNDERVOLTAGE ( DOUBLY — FED ONLY)
INDUCTION GENERATOR 59 OVERVOLTAGE ( DOUBLY— FED ONLY)
OR DOUBLY FED 50/51 OVERCURRENT
INDUCTION GENERATOR GEN ANTI — ISLANDING
NOTE : FUNCTIONS MAY BE INCORPORATED INTO
L THE GENERTOR CONTROL SYSTEM
Rev 8 . 0 January 2010 20
APPENDIX B-TYPICAL ONE-LINE INVERTER CONNECTED GENERATOR BELOW 1000KW.
13 . 8KV LINE no TO OTHER LOADS
FUSE
UTILITY TRANSFORMER
POINT OF COMMON COUPLING
CUSTOMER CUSTOMER CUSTOMER
M GF METER M GF METER GF METER M
OTHER OTHER
CUSTOMER CUSTOMER
LOADS LOADS
CUSTOMER
SERVICE
PANEL
LOCKABLE
ACCESSABLE
DISCONNECT
SWITCH
PROTECTIVE FUNCTIONS
Z UL1741 OR TESTED TO IEEE 1547 . 1
INVERTER k� 50/51 OVERCURRENT
NOTE : FUNCTIONS MAY BE INCORPORATED INTO
J THE INVERTER CONTROL SYSTEM
GEN
PV SYSTEM
FUEL CELL
WIND GENERATOR
MICROTURBINE
ETC .
( note : meter was added to drawing similar to Drawing B
Rev 8 . 0 January 2010 21
APPENDIX C -TYPICAL ONE -LINE SYNCHRONOUS GENERATOR 50KW AND ABOVE
TO SUBSTATION 13.8KV LINE TO OTHER LOADS
1 RECLOSER NEEDED
FUSE iRi15O0KVA AND
` TJABOVE
3 - PHASE (ABOVE 20KVA)
UTILITY TRANSFORMER
POINT OF COMMON COUPLING
M CUSTOMER
GF METER
CUSTOMER
SERVICE
PANEL
LOCKABLE
ACCESSABLE
DISCONNECT
SWITCH
METERING AND PROTECTIVE FUNCTIONS
M
TELEMETRY TO FCU 27 UNDERVOLTAGE
59 OVERVOLTAGE
50/51 OVERCURRENT
5OG/51G GROUND FAULT
SYNCHRONOUS z
810/U OVER/UNDER FREQUENCY
GENERATOR25 SYNC CHECK
EFFECTIVELY 47 PHASE - SEQUENCE VOLTAGE
GROUNDEDI I 32 REVERSE POWER ( 1OOKW AND ABOVE)
46 NEGATIVE SEQUENCE CURRENT (ABOVE 1OOOKW)
- J 40 LOSS OF FIELD (ABOVE 1OOOKW)
ANTI - ISLANDING
NOTE: FUNCTIONS MAY BE INCORPORATED INTO THE
GENERTOR CONTROL SYSTEM BELOW 10OKW
Rev 8 . 0 January 2010 22
APPENDIX D -TYPICAL ONE - LINE INDUCTION GENERATOR LARGER THAN 10OKW
TO SUBSTATION 13 .8KV LINE TO OTHER LOADS
, T , RECLOSER NEEDED
FUSE i R i1500KVA AND
` T ' ABOVE
3 - PHASE (ABOVE 20KVA)
UTILITY TRANSFORMER
POINT OF COMMON COUPLING
M CUSTOMER
GF METER
CUSTOMER
SERVICE
PANEL
LOCKABLE
ACCESSABLE
DISCONNECT
SWITCH
METERING AND
TELEMETRY TO FCUM
PROTECTIVE FUNCTIONS
27 UNDERVOLTAGE
GROUNDING TRANSFORMER 59 OVERVOLTAGE
50/51 OVERCURRENT
F -1 50G/51G GROUND FAULT
52 15 SPEED MATCHING
INDUCTION GENERATOR ' 47 PHASE-SEQUENCE VOLTAGE
OR DOUBLY FED 46 NEGATIVE SEQUENCE CURRENT ( 100KW AND ABOVE)
INDUCTION GENERATOR ' GEN 810/U OVER AND UNDER FREQUENCY ( 100KW AND ABOVE)
32 REVERSE POWER ( 100KW AND ABOVE)
SELF- EXCITATION PROTECTION (AS NEEDED)
ANTI - ISLANDING
NOTE- =UNC-IONS VAY B = NCORPORA=7 INTO -F =
Rev 8 . 0 January 2010 23
APPENDIX E-TYPICAL ONE-LINE INVERTER CONNECTED GENERATOR LARGER THAN 1000KW
TO SUBSTATION 13.8KV LINE TO OTHER LOADS
, 1 , RECLOSER NEEDED
FUSE iRi2500KVA AND
JTJABOVE
3 - PHASE (ABOVE 20KVA)
R UTILITY TRANSFORMER
POINT OF COMMON COUPLING
M CUSTOMER
GF METER
CUSTOMER
SERVICE
PANEL
LOCKABLE
ACCESSABLE
DISCONNECT
SWITCH
METERING AND M
TELEMETRY TO FCU
52
PROTECTIVE FUNCTIONS
UL1741 OR TESTED TO IEEE 1547 . 1
50/51 OVERCURRENT
Z 50G/51G GROUND FAULT (ABOVE 1000KW)
INVERTER 810/U OVER AND UNDER FREQUENCY (ABOVE 1000KW)
_ 27 UNDERVOLTAGE (ABOVE 1000KW)
J 59 OVERVOLTAGE (ABOVE 1000KW)
NOTE: FUNCTIONS MAY BE INCORPORATED INTO THE
GENERTOR CONTROL SYSTEM BELOW 100KW
GEN
PV SYSTEM
FUEL CELL
WIND GENERATOR
MICROTURBINE
ETC .
Rev 8 . 0 January 2010 24