FACILITY RATINGS METHOD TABLE OF CONTENTS

Transcription

1 FACILITY RATINGS METHOD TABLE OF CONTENTS 1.0 PURPOSE SCOPE COMPLIANCE DEFINITIONS RESPONSIBILITIES PROCEDURE Generating Equipment Ratings Transmission Equipment Ratings RECORDS FORMS ATTACHMENTS Uniform Environmental Conditions Table REVISION HISTORY Effective 05/10/2016 Page 1 of 23

2 1.0 PURPOSE 1.1 This procedure documents Westar Energy s Transmission Owner and Generator Owner method to develop and communicate the Facility Ratings for all solely and jointly owned Facilities. [FAC R1, R2 & R3] Effective 05/10/2016 Page 2 of 23

3 2.0 SCOPE 2.1 This method documents the technically sound principles for calculation of Normal and Emergency Facility Ratings of the solely and jointly owned Westar Energy generating units. [FAC R1 & R2] Solely owned generating facilities are rated according to this Facility Rating Method. Jointly owned generating facilities for which Westar Energy is the registered Generator Owner shall also be rated according to this Facility Rating Method. This method of rating generating units complies with SPP Planning Criteria 7.1. This method of rating generating facilities includes all applicable equipment detailed in Section 6.4 of this Facility Rating Method. 2.2 This method documents the technically sound principles for calculation of Normal and Emergency Facility Ratings of the solely and jointly owned Westar Energy Transmission Facilities regardless of voltage. [FAC R3] This method of rating Transmission Facilities considers SPP Planning Criteria 7.2. This method of rating Transmission Facilities includes all applicable equipment detailed in Section 6.5 of this Facility Rating Method. All circuit ratings are based on summer seasonal facility ratings, except as noted in Section The categories of equipment rated include, but are not limited to: generators, conductors, transformers, relay protective devices, terminal equipment, and series and shunt compensation devices as detailed in Sections 6.4 and 6.5 of this Facility Ratings Method. [FAC R2.4.1 & R3.4.1] Effective 05/10/2016 Page 3 of 23

4 3.0 COMPLIANCE 3.1 Each Generator Owner shall have documentation that shows how its Facility Ratings were determined as identified in FAC Requirement Each Generator Owner shall have a documented Facility Ratings methodology that includes all of the items identified in FAC Requirement 2, Parts 2.1 through Each Transmission Owner shall have a documented Facility Ratings methodology that includes all of the items identified in FAC Requirement 3, Parts 3.1 through Each Transmission Owner shall have evidence, such as a copy of a dated electronic note, or other comparable evidence to show that it made its Facility Ratings methodology available for inspection within 21 calendar days of a request in accordance with FAC Requirement 4. The Generator Owner shall have evidence, such as a copy of a dated electronic note, or other comparable evidence to show that it made its documentation for determining its Facility Ratings or its Facility Ratings methodology available for inspection within 21 calendar days of a request in accordance with FAC Requirement Each Transmission Owner and Generator Owner shall have evidence to show that its Facility Ratings are consistent with the documentation for determining its Facility Ratings as specified in Requirement R1 or consistent with its Facility Ratings methodology as specified in FAC Requirements R2 and R3 (Requirement R6). 3.6 Each Generator Owner shall have evidence, such as a copy of a dated electronic note, or other comparable evidence to show that it provided its Facility Ratings to its associated Reliability Coordinator(s), Planning Coordinator(s), Transmission Planner(s), Transmission Owner(s) and Transmission Operator(s) in accordance with FAC Requirement R Each Transmission Owner (and Generator Owner subject to Requirement R2) shall have evidence, such as a copy of a dated electronic note, or other comparable evidence to show that it provided its Facility Ratings and identity of limiting equipment to its associated Reliability Coordinator(s), Planning Coordinator(s), Transmission Planner(s), Transmission Owner(s) and Transmission Operator(s) in accordance with Requirement R8. Effective 05/10/2016 Page 4 of 23

5 4.0 DEFINITIONS 4.1 Book Rating: The rating provided by the manufacturer or a suitable conductor reference manual. Conditions for overhead conductor are generally based upon a 50 degree C temperature rise above a 25 degree C ambient temperature with 2 ft/sec wind perpendicular to the conductor. 4.2 Emergency Rating: The rating as defined by the equipment owner that specifies the level of electrical loading or output that a system, facility, or element can support, produce, or withstand for a finite period. The rating assumes acceptable loss of equipment life or other physical or safety limitations for the equipment involved. 4.3 Equipment Rating: The maximum and minimum voltage, current, frequency, real and reactive power flows on individual equipment under steady state, short-circuit and transient conditions, as permitted or assigned by the equipment owner. 4.4 Facility Rating: The maximum or minimum voltage, current, frequency, or real or reactive power flow through a facility that does not violate the applicable equipment rating of any equipment comprising the facility. 4.5 Generation Facility: Facilities that comprise all current carrying equipment from the generating unit to the point of interconnection with the Transmission Owner. 4.6 Generator Owner: Entity that owns and maintains generating units. 4.7 High Operating limit or High Alarm limit: Terms used in the displays of the SCADA / EMS real-time system and are named as such by the system developer / manufacturer. These terms are functionally equivalent to Emergency Rating. 4.8 High Warning limit: Term used in the displays of the SCADA / EMS real-time systems and is named as such by the system developer / manufacturer. 4.9 Manufacturer s Nameplate Ratings: Ratings provided by the manufacturer of equipment are assumed to consider design criteria, ambient conditions, operating limitations and other design assumptions Normal Rating: The rating as defined by the equipment owner that specifies the level of electrical loading that a system, facility, or element can support or withstand through the daily demand cycles without loss of equipment life Overhead Conductor: A wire or combination of wires not insulated from one another suitable for carrying an electric current. Overhead conductor is separate and distinct from rigid bus. Effective 05/10/2016 Page 5 of 23

6 4.12 Rigid Bus: A solid or tubular conductor Transmission Facility: Facilities that comprise the current carrying equipment connected in series between circuit breakers or comparable switching devices. A Transmission Facility shall also include substation terminal equipment including, but not limited to breakers, switches, and conductor Transmission Owner: The entity that owns and maintains Transmission Facilities. Effective 05/10/2016 Page 6 of 23

7 5.0 RESPONSIBILITIES 5.1 Facility Ratings Method is reviewed and updated by a cross-functional team of subject matter experts within Westar Energy not less frequently than once per calendar year and coordinated by NERC Compliance. The cross-functional team includes representatives from Generation Reliability Engineering, NERC Compliance, Substation Engineering, System Planning, and System Operations. 5.2 Facility Ratings Method is approved by the Director of Generation Support, the Director of Transmission & Substation Construction Services, and the Executive Director of System Operations. 5.3 Facility Ratings Method shall be posted on the Westar Energy public OASIS site. 5.4 Facility Ratings developed shall be provided to SPP to ensure accurate modeling of steady-state data in accordance with the procedures developed and maintained by the SPP Model Development Working Group. 5.5 Westar Energy shall provide requested information as specified below (for its solely and jointly owned Facilities that are existing Facilities, new Facilities, modifications to existing Facilities and re-ratings of existing Facilities) to its associated Reliability Coordinator(s), Planning Coordinator(s), Transmission Planner(s), Transmission Owner(s) and Transmission Operator(s): [FAC R7][FAC R8] As scheduled by the requesting entities: [FAC R8.1] Facility Ratings [FAC R8.1.1] Identity of the most limiting equipment of the Facilities [FAC R8.1.2] Within 30 calendar days (or a later date if specified by the requester), for any requested Facility with a Thermal Rating that limits the use of Facilities under the requester s authority by causing any of the following: 1) An Interconnection Reliability Operating Limit, 2) A limitation of Total Transfer Capability, 3) An impediment to generator deliverability, or 4) An impediment to service to a major load center: [FAC R8.2] Identity of the existing next most limiting equipment of the Facility [FAC R8.2.1] The Thermal Rating for the next most limiting equipment identified in Requirement R8, Part [FAC R8.2.2] Effective 05/10/2016 Page 7 of 23

8 6.0 PROCEDURE 6.1 The applicable Facility Rating shall equal the most limiting applicable Equipment Rating of the individual equipment that comprises the Facility. [FAC R1.2, R2.3 & R3.3] Solely owned Facilities are rated according to this Facility Ratings Method. Facilities that are jointly owned shall utilize the lesser rating as developed by each owner consistent with the facility owner s applicable Facility Rating Method. [FAC R6] 6.2 If applicable, the following items will be considered to determine ratings: ratings provided by the equipment manufacturer, applicable industry standards, design criteria, ambient conditions, operating limitations, and other assumptions. [FAC R1.1] [FAC R2.1] [FAC R2.2] [FAC R3.1] [FAC R3.2] 6.3 Uniform Environmental Conditions [FAC R2.2.3 & R3.2.3] Solar absorptivity is the ratio of incident solar radiant energy absorbed by a material body to the incident solar radiant energy absorbed by a blackbody at the same temperature. Solar absorptivity is set to 0.9. It is assumed that solar gain is based on full sun and a clear atmosphere Infrared emissivity is the ratio of infrared radiant energy emitted by a material body to the infrared radiant energy radiated by a blackbody at the same temperature. Infrared emissivity is set to Wind speed is assumed to be 2 ft/sec at a 90-degree angle to the conductor for overhead conductor. Wind speed is assumed to be 3 ft/sec at a 90- degree angle to the conductor for rigid bus installed in substations or switching stations Ambient temperature used for calculation of ratings is 40 degrees C during the summer season and is 10 degrees C during the winter season For purposes of rating calculation, elevation above sea level for Westar Energy is 1,155 feet For purposes of rating calculation, the azimuth of outdoor facilities is east-west For purposes of rating calculation, the latitude of outdoor facilities is 35 degrees north For purposes of rating calculation, the apparent solar time is 2:00 pm (1400 hours). Effective 05/10/2016 Page 8 of 23

9 6.4 Generating Equipment Ratings Bus Isolated-phase or non-segregated bus shall be rated per the Manufacturer s Nameplate Rating. If no Manufacturer s Nameplate Rating is available, the design rating available on manufacturer s schematic drawings or manufacturer s test data shall be used. The Normal and Emergency Ratings shall be equal Rigid bus shall be rated based on the engineered design capacity of the bus or based on manufacturer s rating. The Normal Rating and Emergency Rating shall be equal Circuit Breaker Circuit breaker continuous Normal Rating and Emergency Rating shall be set to the Manufacturer s Nameplate Rating of the device Conductor Overhead conductor Normal Rating shall be rated based on the engineered design capacity of the conductors. In cases where original engineering data or design criteria on overhead conductor are not available, the conductor Normal Rating and Emergency Rating shall be set to the manufacturer s rating. This conservative approach is used in consideration of the age of facilities currently in service. The Normal and Emergency Ratings shall be equal Underground cable Normal Rating shall be rated based on the engineered design capacity of the cable or based on manufacturer s rating. The Normal Rating and Emergency Rating shall be equal Current Transformer (CT) CT continuous Normal Rating and Emergency Rating shall be set to the tap setting times the thermal rating factor of the CT at that tap if known. An unspecified thermal rating factor is assumed to be 1.0. CTs may be rated according to Appendix PL-2.E of SPP Planning Criteria as determined appropriate by subject matter expert Generating Unit Effective 05/10/2016 Page 9 of 23

10 Hydrogen cooled generators shall be rated in MVA according to Manufacturer s Nameplate Rating or capability curve for the maximum rated hydrogen pressure. The Normal and Emergency Ratings shall be equal Air cooled generators shall be rated in MVA according to the Manufacturer s Nameplate Rating or capability curve for the rated ambient air conditions. The Normal and Emergency Ratings shall be equal Power Transformer Normal Rating on generator step-up transformers shall be set to the maximum allowable Manufacturer s Nameplate Rating for the rated ambient air conditions with the Emergency Rating set equal to the Normal Rating The Emergency Rating of the generator step-up transformer, which is equal to the continuous transformer nameplate normal rating, shall be used as the High Operating limit or High Alarm limit in the SCADA / EMS real-time systems. The High Warning limit in the SCADA / EMS real-time systems for such generator step-up transformer shall be set at either 90% of the High Alarm limit or a value less than the High Alarm Limit as approved by the Director of Transmission and Generation System Operations based upon past operating experience Protective Device Effective 05/10/2016 Page 10 of 23

11 6.4.8 Protective relays shall have ratings established in such a way as to not exceed the manufacturer s specification for continuous current-carrying capacity of the device. If manufacturer s specification is not available, protective relays are assumed to be capable of carrying 5 amperes of current delivered to the input of the relay. Protective relays have only a continuous rating which establishes the Normal Rating and Emergency Rating at the same value Switches Switch Normal Rating and Emergency Rating shall be set to the Manufacturer s Nameplate Rating of the device Series Reactive Compensation Device These devices do not exist within generating facilities Shunt Reactive Compensation Device These devices do not exist within generating facilities. Effective 05/10/2016 Page 11 of 23

12 6.5 Transmission Equipment Ratings Bus Rigid bus, Normal and Emergency Rating, shall be rated in accordance with IEEE Standard 605 IEEE Guide for Bus Design in Air Insulated Substations Circuit Breaker Circuit breaker continuous Normal Rating and Emergency Rating shall be set to the Manufacturer s Nameplate Rating of the device Current Transformer (CT) CT continuous Normal Rating and Emergency Rating shall be set to the tap setting times the thermal rating factor of the CT at that tap if known. An unspecified thermal rating factor is assumed to be 1.0. CTs may be rated according to Appendix PL-2.E of SPP Planning Criteria as determined appropriate by subject matter expert Conductor For conductors used on the Westar system except SSAC (ACSS) overhead conductors shall be rated at 85 degrees C conductor temperature under normal conditions and 100 degrees C conductor temperature under emergency conditions unless designed for a lower final conductor temperature, then it should be rated at that temperature. SSAC conductors shall be rated at 200 degrees C maximum conductor temperature for Normal Rating and Emergency Rating unless designed for a lower final conductor temperature, then it should be rated at that temperature. In cases where original engineering data or design criteria on transmission lines are not available, the conductor Normal Rating and Emergency Rating shall be set equal to the manufacturer s Book Rating or the Book Rating of a suitable reference for the conductor type. This conservative approach is used in consideration of the age of Transmission Facilities currently in service. Loading at or below the Emergency Rating of overhead conductor is a continuous rating. Conductor ratings are calculated using the procedures in IEEE Standard 738 IEEE Standard for Calculating the Current-Temperature of Bare Overhead Conductors. Effective 05/10/2016 Page 12 of 23

13 For transmission lines that are constructed as double circuit but are operated as a single circuit with phase conductors in parallel, a composite conductor rating is calculated based on the individual line conductors, the line impedances, and current sharing relationship of the line conductors utilized (current divider). This calculation utilizes individual conductor ratings consistent with and ensures the most limiting conductor rating will not be exceeded with the line operating as a single circuit For conductors used on the Westar system except SSAC (ACSS) overhead conductors shall be rated at 85 degrees C conductor temperature under normal conditions and 100 degrees C conductor temperature under emergency conditions unless designed for a lower final conductor temperature, then it should be rated at that temperature. SSAC conductors shall be rated at 200 degrees C maximum conductor temperature for Normal Rating and Emergency Rating unless designed for a lower final conductor temperature, then it should be rated at that temperature. Loading at or below the Emergency Rating of overhead conductor is a continuous rating. Conductor ratings are calculated using the procedures in IEEE Standard 738 IEEE Standard for Calculating the Current-Temperature of Bare Overhead Conductors Underground cable ratings are based on manufacturer s Book Rating or the Book Rating of a suitable reference or engineering analysis for Normal Rating, Emergency Rating and short term Emergency Rating to avoid damage to the insulation due to thermal expansion. IEEE Standard 835 IEEE Standard Power Cable Ampacity Tables may be used in calculating the underground cable ratings absent manufacturer s data Power Transformer Normal Rating on transmission transformers shall be set to the maximum allowable Manufacturer s Nameplate Rating. The Emergency Rating is typically set to 110% of the Normal Rating. It may be set higher or lower based upon evaluation of field testing, operational history of the unit, and real time monitoring of oil temperatures. The Emergency Rating of transmission transformers is an eight (8) hour rating Primary Fuse Primary fuse continuous Normal Rating and Emergency Rating shall be set to the Manufacturer s Nameplate Rating of the device Protective Device Effective 05/10/2016 Page 13 of 23

14 Protective relays shall have ratings established in such a way as to not exceed the manufacturer s specification for continuous current-carrying capacity of the device. If manufacturer s specification is not available, protective relays are assumed to be capable of carrying 5 amperes of current delivered to the input of the relay. Protective relays have only a continuous rating which establishes the Normal Rating and Emergency Rating at the same value Series Reactive Compensation Device Series compensation devices shall be rated consistent with the voltage at which they are operated. Nominal operating voltage may be different from the design voltage. Reactive devices do not have any applicable Emergency Rating. Series connected reactors are specified and rated according to IEEE Standard IEEE Standard Requirements, Terminology, and Test Code for Dry- Type Air-Core Series-Connected Reactors Shunt Reactive Compensation Device Shunt compensation devices shall be rated consistent with the voltage at which they are operated. Nominal operating voltage may be different from the design voltage. Reactive devices do not have any applicable Emergency Rating. Transmission shunt capacitors are specified and rated according to: IEEE Standard 18 IEEE Standard for Shunt Power Capacitors; IEEE Standard 1036 IEEE Guide for the Application of Shunt Power Capacitors; and IEEE Standard C37.99 IEEE Guide for the Protection of Shunt Power Capacitors. Transmission shunt reactors are specified and rated according to the IEEE Standard C57.21 IEEE Standard Requirements, Terminology, and Test Code for Shunt Reactors Rated Over 500 kva Switches Switch Normal Rating and Emergency Rating shall be set to the Manufacturer s Nameplate Rating of the device Wave Trap Epoxy-encapsulated wave traps shall have Normal Rating and Emergency Rating set to Manufacturer s Nameplate Rating. Drytype air-cored wave traps that are not epoxy-encapsulated wires shall have the Emergency Rating set to 110 percent of Manufacturer s Nameplate Rating. Effective 05/10/2016 Page 14 of 23

15 The composite rating on a terminal-to-terminal basis of Transmission Facilities shall be set to the most limiting equipment for normal and emergency conditions. Transmission Facility Ratings shall be updated as equipment is replaced and communicated to Transmission System Operations and to the Southwest Power Pool when such facilities are placed in service. For Multi-Breaker configuration (breaker-and-half, Ring Bus, or double breaker/double bus), the equipment rating on the substation side of the terminal shall be rated based on one-breaker open. If the ratings of terminal equipment (such as breakers, switches, etc.) are not identical at one end of the transmission line or transformer, then the equipment with the higher rating is assumed to be open when developing the overall facility rating. [FAC R6] Short-term Emergency Rating, i.e. 30 minute ratings, may be established on a case-by-case basis on equipment that may experience an overload condition while predetermined mitigation steps are executed. Short-term Emergency Ratings and their corresponding time limits will only be established after a detailed review of equipment limitations and the documentation of appropriate automatic or operator-controlled mitigation steps designed to relieve the overload to within Normal Rating or Emergency Rating. Appropriate mitigation steps must be determined to be possible to be completed within the prescribed short-term time limit. All other short-term Emergency Rating shall be set equal to the existing Emergency Rating of the facility. 6.6 The Emergency Rating of the Transmission Facilities shall be used as the High Operating limit or High Alarm limit in the SCADA / EMS real-time systems. The High Warning limit in SCADA/EMS shall be the lesser of 90% of the High Alarm limit or the Normal Rating. 6.7 The applicable Facility Rating shall be modified to account for known operating limitations. Such limitations, in general, are applicable only on a short-term basis and only within an operational framework, such as the realtime SCADA / EMS systems. This includes temporary derating of impaired equipment consistent with good utility practice or temporary derating of a facility due to topology changes. [FAC R2.2.4 & R3.2.4] Effective 05/10/2016 Page 15 of 23

16 6.8 Other considerations may be taken into account to define the ampacity rating of facilities. Heat transfer from overhead conductor or rigid bus may be conducted to any attached equipment and equipment temperature limitations may be taken in account. Parallel conductors or busses in close proximity may adversely impact the ability to radiate heat and may be considered to reduce the rating an appropriate amount. Parallel conductors used as substation bus may have a mutual inductance between them that can result in an impedance imbalance and uneven loading thereby reducing the overall ampacity of the bus. Bus fittings and accessories must be properly installed in accordance with manufacturer s recommendation to ensure that they do not limit Facility Ratings. 6.9 Under abnormal situations, winter ratings of the affected facilities can be used in the EMS, in the winter season, where applicable upon approval of the Director of Transmission and Generation System Operations. In such cases the associated EMS alarms shall be modified to accommodate the winter rating. Also in such cases the relay loadability per PRC-023 shall be verified to meet the new rating, or relay setting modifications shall be made to accommodate the winter rating. Upon return to normal operating conditions or change in season, the rating and the accompanying EMS alarms shall be returned to the original rating. Effective 05/10/2016 Page 16 of 23

17 7.0 RECORDS 7.1 The Generating Facility Ratings are developed by Generation Reliability Engineering and are maintained on a secured network drive. 7.2 The Transmission System Facility Ratings are developed and maintained by System Planning on a secured network drive. Effective 05/10/2016 Page 17 of 23

18 8.0 FORMS 8.1 None Effective 05/10/2016 Page 18 of 23

19 9.0 ATTACHMENTS 9.1 Uniform Environmental Conditions Table Conditions Input Units Apparent Solar Time 1400 hours Atmosphere Clear Azimuth of Line 90 (E/W) degrees Elevation (ft above sea level) 1155 ft Emissivity 0.88 Latitude 35 N degrees Solar Absorptivity 0.9 Temperature - Ambient Air - Summer 40 degrees C Temperature - Ambient Air - Winter 10 degrees C Temperature Emergency 100 degrees C Temperature Normal 85 degrees C Wind Angle 90 degrees Wind Speed for Conductor 2 ft/sec Wind Speed for Rigid Tubular Bus 3 ft/sec Effective 05/10/2016 Page 19 of 23

20 9.2 Multi-Breaker Facility Layout Diagram Effective 05/10/2016 Page 20 of 23

21 9.3 Single-Breaker Facility Layout Diagram Effective 05/10/2016 Page 21 of 23

22 10.0 REVISION HISTORY Effective Date: Author(s): Approved By: Superseded Date: Change History: 5/10/2016 Facility Ratings Method Team 05/14/2015 Facility Ratings Method Team 03/27/2014 Facility Ratings Method Team 09/06/2013 Facility Ratings Method Team 05/01/2013 Facility Ratings Method Team 12/18/2012 Facility Ratings Method Team Dave Benak Mark Mayworm John Olsen Dave Benak Mark Mayworm Tom Stuchlik Dave Benak Mark Mayworm Tom Stuchlik Dave Benak Mark Mayworm Dracy Jenkins Mark Mayworm Dracy Jenkins Mark Mayworm 5/14/2015 Updated references to SPP Criteria. Updated Responsibilities and Records for appropriate personnel. Updated Section 4.1. Added Section /27/2014 Revised standard references throughout. Moved Isolatedphase and Rigid bus under a new Bus subsection. Revised Section Added Section /06/2013 Revised Sections , , , 6.6, and Added Sections and Removed Section 6.7. Added Generation Plant Support Engineering to Section /01/2013 Added Sections 4.13, 4.14, and 6.6. Removed Standards & Quality Assurance group from the Responsibilities section. 12/18/2012 Revised Sections 2.2 and 4.11; Added Sections 9.2 and 9.3: Multi-Breaker Facility Layout Diagram and Single Breaker Facility Layout Diagram. 01/01/2012 Updated to include references to FAC-008-3; Annual Review 01/01/2012 Facility Ratings Method Team Tom Stuchlik Dracy Jenkins Mark Mayworm 8/11/ URP NERC FAC- 008 Generation Facility Rating Methodology Combined System Planning Policy 0602 and URP NERC FAC-008 Generation Facility Rating Methodology Effective 05/10/2016 Page 22 of 23

23 3/22/ System Planning Policy 0602 END Effective 05/10/2016 Page 23 of 23