KO_Exciter_Draft_SOW_2.pdf

Power Plant: Kortes Excitation System Replacement Location: Kortes Power Plant Supply contract

Tab le of Contents

SECTION 1. GENERAL REQUIREMENTS

1.1. DELIVERY AND SHIPPING

1.2. RECLAMATION POINTS OF CONTACT

1.3. WARRANTY

1.4. INSPECTION

1.5. TESTING AND FIELD ENGINEERING

SECTION 2. DETAILED SPECIFICATIONS

2.1 OVERVIEW

2.2 BACKGROUND

2.3 GENERAL

2.4. CODES AND STANDARDS

2.5. EQUIPMENT RATINGS AND SITE CONDITIONS

2.6. EXCITATION SYSTEM DESIGN REQUIREMENTS

2.7. EXCITATION SYSTEM FUNCTIONAL REQUIREMENTS

2.8. EXCITATION SYSTEM ENCLOSURE/CUBICLE

2.9. SCR BRIDGES

2.10. FIELD CIRCUIT EQUIPMENT

2.11. MEDIUM VOLTAGE RECTIFIER TRANSFORMER

2.12. METERING TRANSFORMER

2.13. VOLTAGE REGULATION EQUIPMENT

2.14. HMI TOUCH SCREEN

2.15. DATA LOGGING (OSCILLOGRAPHY) AND SCADA INTERFACE

2.16. Instrument transformers

2.17. METAL-ENCLOSED INTERRUPTER SWITCH

2.18. FUSES

2.19. INTERFACE AND UPGRADE OF EXISTING CONTROL CIRCUITS, DEVICES AND REMOTE MONITORING AND

CONTROL BOARD

2.20. REMOTE CONTROL BOARD FIELD CURRENT AND VOLTAGE METERS

2.21. REMOTE CONTROL BOARD INDICATING LIGHTS GENERAL REQUIREMENTS

2.22. NAMEPLATE GENERAL REQUIREMENTS

2.23. CABLE, WIRING AND CONNECTIONS

2.24. TERMINAL BLOCKS

2.25. AUXILIARY RELAYS

2.26. RELAY TESTING BLOCKS

2.27. DESIGN DATA, TECHNICAL INFORMATION, AND EQUIPMENT AND MATERIAL LISTS

2.28. REQUIRED FACTORY TESTING

2.29. INSTALLATION INSTRUCTIONS AND DRAWINGS

2.30. REQUIRED FIELD TESTING AND COMMISSIONING

2.31. TRAINING

2.32. SPARE PARTS

2.33. Pre-Installation, Installation and Commissioning Site Visits

2.34. DRAWINGS, MANUALS, AND TECHNICAL INFORMATION GENERAL FORMAT REQUIREMENTS

SECTION 3. REFERENCE DRAWINGS

SECTION 4. TECHNICAL SUBMITTALS

SECTION 5. SAFETY AND SITE SECURITY SUBMITTALS

Solicitation Number ???????????????

Exciter Furnishment

Kortes Powerplant

Carbon County, Wyoming

SECTION 1 . GENERAL REQUIREMENTS

1.1. DELIVERY AND SHIPPING

A. The Bureau of Reclamation desires a delivery date on or before _JULY 2028___.

Shipping shall be FOB destination. The Project Site address is Kortes Power plant.

B. Components, material, and equipment packed for shipment and shall show the purchase order number and serial number of parts contained.

C. On the same day that any shipment is originated, a transmittal, including the following, shall be emailed to the Project Manager. See Section 1.2.

1. Packing List - two (2) copies

2. Bill of Lading - Original and two (2) copies

3. Packing list shall also accompany each shipment.

1.2. RECLAMATION POINTS OF CONTACT

Project Manager: Kaitlin Hasler

Technical Expert: US Bureau of Reclamation, Thomas Murphy, Electrical Engineer, Power Division, tlmurphy@usbr.gov

Contracting Officer (CO): __________________________________________________ mailto:tlmurphy@usbr.gov

1.3. WARRANTY

Manufacturer shall warrant to the Bureau of Reclamation that the apparatus or services to be furnished hereunder will be of the highest quality and free from defects in material, workmanship, and title and will be of the kind designated in the pertinent purchase order.

The Manufacturer's warranty shall be effective for a period of sixty (60) months after commissioning. Terms of the Manufacturer's excitation system warranty shall be included in the bid proposal.

1.4. INSPECTION

A representative of the Bureau of Reclamation shall be allowed free access at a reasonable time to the Manufacturer's shop for inspection of the equipment or any of its parts. Any work or material found to be defective, or which does not meet the requirements of this Specification may be rejected and shall be replaced by the Manufacturer at his own expense. Such inspection, however, shall not relieve the Manufacturer from responsibility for the quality and correctness of the work.

1.5. TESTING AND FIELD ENGINEERING

A. The Exciter system shall be tested at the factory for satisfactory operation, and electrical integrity. Refer to Section 2.25, Required Factory Testing.

B. The Bureau of Reclamation reserves the right to be present at the factory for testing of any of the exciter system components. Manufacturer shall provide the testing schedule to the Bureau of Reclamation 30 days prior to starting of factory tests.

C. A Certified copy of the test report shall be sent to the Bureau of Reclamation Engineer following testing of the exciter system and prior to shipment to site.

D. The Manufacturer, at their discretion, may provide a field service engineer to conduct an evaluation of the apparatus and other material at time of delivery to site. Costs of the field service engineer for this purpose, shall be included in the manufacturer’s base bid.

E. Provide a list of required field tests and commissioning steps, that incorporates the field test and commissioning requirements as specified herein, to be performed after assembly and installation. Refer to Section 2.17, Required Field Testing and Commissioning

SECTION 2 . DETAILED SPECIFICATIONS

2.1 OVERVIEW

The Bureau of Reclamation, Missouri Basin Region, Wyoming Area Office, Kortes power plant requires the furnishment of a replacement exciter system. Ancillary to furnishing the new exciter, the contractor will perform two site visits. The first will be used to verify exciter component essential characteristics, and to collect interface and installation requirements prior to supplying the new components. The second visit will be used to provide authorized factory representative consulting to support government installation, testing and commissioning of the exciter system. The authorized factory representative will also provide onsite training on maintenance, operation, and testing. Onsite training facilities will be provided by the government.

2.2 BACKGROUND

The Kortes power plant is in Carbon County Wyoming. The powerplant began operation in 1958 and contains three hydroelectric generators rated for 15.33MVA at 6.9kV. This plant is also designated as a black start facility for Wyoming. The existing exciter was designed and built by Siemens-Allis. The system currently in use is a shaft-mounted rotating DC exciter. The exciter is no longer supported, and spare parts are not readily available.

2.3 GENERAL

The requirement is for a new exciter system that will hard-wired interfaced to existing remote monitoring and control, and protection. The government will provide labor for removal of old equipment, installation of the new exciter system, exciter testing and commissioning.

Work to Be Provided

1. Exciter system designed and rated for service as specified herein.

2. Associated equipment, cables, wiring, and materials required for exciter system operation, monitoring and control, and maintenance as specified herein. This shall include:

a. Power Potential Transformer (PPT)

b. PPT protection relay (87EX)

c. Current transformers (CTs) for the PPT

d. Potential transformers (PTs) for use by the new exciter.

e. Excitation Power Circuit Breaker (52EX).

f. Relay test blocks to provide for testing of excitation system circuits.

g. Remote exciter control switches, meters, indicator lights and nameplates for the existing control panels.

h. Cables, wiring, connections, and other associated hardware required for exciter system installation.

i. Exciter system spare parts.

3. All factory tests and inspections specified and performed.

4. Schedules, installation instructions, manuals, drawings, manufacturing and quality procedures, test reports and other information and documents specified herein.

5. Fabrication and delivery of exciter system components that can be passed through a

7 ft x 6 ft access for installation

6. Utilizes existing cable trays, embedded electrical conduits and floor penetrations where practicable.

7. Ancillary services to provide an onsite factory authorized representative to:

a. Evaluate and verify exciter system installation, equipment, and material requirements.

b. Develop and supply exciter system installation instructions.

c. Provide excitation system maintenance and operation training.

d. Provide installation direction and consulting.

e. Provide testing and commissioning direction and consulting.

8. Disassembly at factory if required for shipment.

9. Packaging of exciter system, pieces, and spare parts for transport.

10. Delivery of the exciter system and associated equipment, materials, and spare parts to the Kortes power plant prior to installation.

A. Work to be Performed by Government labor

1. Removal of old exciter equipment.

2. Installation of the new exciter and associated equipment, cabling, and wiring per supplied drawings and specifications.

3. The Bureau of Reclamation Technical Service Center (TSC) will assist with testing and commissioning activities.

4. Modeling will be performed by the Bureau of Reclamation Technical Service

Center (TSC).

5. Assist (TSC) with Protective device settings.

2.4. CODES AND STANDARDS

A. Work provided under this specification shall be in strict conformance with the latest edition and latest addenda thereto, as of the time work is performed, of the applicable codes, standards, regulation procedures and tests of the following organizations:

1. American National Standards Institute (ANSI)

2. American Society for Testing Materials (ASTM)

3. Institute of Electrical and Electronics Engineers (IEEE):

a. IEEE Std C37.04TM-2018,

b. IEEE Std C37.09TM-2018, and

c. IEEE Std C37.010TM-2016.

11. American Society of Mechanical Engineers (ASME)

12. ASME Y14.1-12, Decimal Inch Drawing Sheet Size and Format

13. ASME Y14.1-2005(2010), Decimal Inch Drawing Sheet Size and Format

14. National Institute of Building Sciences (NIBS)

15. NIBS NCS-14, United States National CAD Standards, Version 6

16. Institute of Electrical and Electronic Engineers (IEEE)

17. IEEE 315-1975(1993), Graphic Symbols for Electrical and Electronics Diagrams

(Including Reference Designation Letters)

18. IEEE C37.2-2008, Electrical Power System Device Function Numbers, Acronyms, and Contact Designations

19. IEEE Y32.9-1972(1989), Graphic Symbols for Electrical Wiring and Layout

Diagrams Used in Architecture and Building Construction

20. IEEE 80-2000, Safety in AC Substation Grounding

21. IEEE 81-1983, Measuring Earth Resistivity, Ground Impedance, and Earth Surface

Potentials of a Ground System

22. IEEE 142-2007, Grounding of Industrial and Commercial Power Systems

23. IEEE 837-2002, Qualifying Permanent Connections Used in Substation Grounding

24. IEEE C2-2007, National Electrical Safety Code (NESC)

25. IEEE 421.1-07, Definitions for Excitation Systems for Synchronous Machines

26. IEEE 421.2-90, Identification, Testing, and Evaluation of the Dynamic

Performance of Excitation Control Systems

27. IEEE 421.3-97(2004), High-Potential Test Requirements for Excitation Systems for Synchronous Machines

28. IEEE 421.5-05, Excitation System Models for Power System Stability Studies

29. IEEE C37.16-09, Preferred Ratings, Related Requirements, and Application

Recommendations for Flow Voltage AC (635 V and Below) and DC (3200 V and Below) Power Circuit Breakers

30. IEEE C37.20.1-02(2007), Metal-Enclosed Low-Voltage Power Circuit Breaker Switchgear

31. IEEE C50.13-05, Cylindrical-Rotor 50Hz and 60Hz, Synchronous Generators Rated 10 MVA and Above

32. IEEE C57.12.01-05, Dry-Type Distribution and Power Transformers Including Those with Solid Cast and/or Resin Encapsulated Windings

33. IEEE C57.12.91-11, Test Code for Dry-Type Distribution and Power

34. IEEE C57.13-08, Instrument Transformers

35. National Electrical Manufacturers Association (NEMA)

36. NEMA ICS 1-2000(2008), Industrial Control and Systems: General Requirements

37. NEMA ICS 5-02(2010), Industrial Control and Systems: Control Circuit and Pilot

Devices

38. National Fire Protection Association (NFPA)

39. NFPA 70-2020 National Electrical Code (NEC)

40. ASTM International (ASTM)

41. ASTM B 3-01(2007), Soft or Annealed Copper Wire

42. ASTM B 8-04, Concentric-Lay-Stranded Copper Conductors, Hard, Medium-Hard, or Soft

43. ASTM B 228-04, Concentric-Lay-Stranded Copper-Clad Steel Conductors

44. ASTM D1535-12, Standard Practice for Specifying Color of the Munsell System

45. Underwriters Laboratories (UL)

46. UL 467-2004 Grounding and Bonding Equipment

47. UL 1066-12 Low-voltage AC and DC Power Circuit Breakers Used in Enclosures

48. American Society of Heating, Refrigerating and Air-Conditioning Engineers

(ASHRAE)

49. ASHRAE 52.2-07, Method of Testing General Ventilation Air- Cleaning Devices for Removal Efficiency by Particle Size

50. US Bureau of Reclamation (USBR) FIST 3-8-11, Operation, Maintenance, and

Field Test Procedures for Protective Relays and Associated Circuits

51. Western Electricity Coordination Council (WECC) SCADA and annunciation requirements

2.5. EQUIPMENT RATINGS AND SITE CONDITIONS

A. Elevation: 5962 feet.

B. Maximum indoor ambient temperature: 40 degrees Celsius.

C. Generator Rating: 15.33MVA D. Generator Terminal Voltage: 6.9kV E. Rated Field Current: 370A F. Rated Field Voltage: 250V G. Field Resistance _.71_Ω at _40 _°C H. Frequency: 60Hz I. Power Factor: 0.9 J. Ambient Temperature: -10°C to 12.7°C K. Control Power: 125VDC L. Turbine Type: Francis M. Exciter Ceiling Voltage: _TBD_VDC N. Exciter Ceiling Current: 626.76 A O. Station Service Supply: 480VAC, 3phase P. Access Restriction - 7x6ft Q. Auxiliary voltage available for operation of control devices is 125 Volts DC. Auxiliary voltages for operation of fans, lights, and receptacles are 120 Volts, single-phase and 480Volts, three-phase, at 60 Hertz.

2.6. EXCITATION SYSTEM DESIGN REQUIREMENTS

A. Designed to utilize existing cable trays, existing embedded electrical conduits, and floor penetrations where practicable.

B. Designed to interface between the new exciter and the existing plant equipment based on supplied drawings as well as incorporating additional interface requirements specified herein. This includes design making all systems modified for this project functional.

C. Supply all equipment, cabling, accessories, and hardware necessary to make a functioning exciter and connections between the exciter and existing plant equipment.

D. Modular construction to permit individual module removal for inspection, diagnostics, repair, or replacement.

E. Design excitation cabinet to have separation between high arc flash available energy equipment such as the power bridges, supply breaker and incoming power cables, and the control equipment.

F. Provide modular draw out type SCR bridge (power converter) design to be interchangeable between units.

G. Continuous Capacity: 115 percent of rated generator field current, minimum.

H. Equipment to function up to 200 percent overspeed (120 Hz) minimum.

I. Designed with following features:

1. Redundant Digital AVR and firing circuits if separate.

2. Digital AVR set point adjuster.

3. Manual (DC) regulator (for test purposes).

4. Digital DC regulator set point adjuster.

5. Adjuster follower that provides set point tracking between manual and automatic modes.

6. Reactive current compensator.

7. Power System Stabilizer (PSS), IEEE type PSS2B.

8. Limiters:

a. Voltz-per-hertz (HXL).

b. Over-excitation limiter (OEL).

c. Under-excitation Limiter (UEL).

d. Synchronous machine terminal overvoltage limiter.

9. Protective Relaying (separate from main and redundant controllers).

a. Over-Excitation Protection (OEP).

b. Vols-Per-Hertz Protection (HXP).

10. Redundant full wave rectifying SCR bridge(s).

11. Synchronous machine field circuit discharge equipment.

12. Generator field voltage and current transducers.

13. Excitation system power supplies: Use generator bus to provide the AC voltage needed for the excitation equipment. Control circuits powered by 125VDC from cabinet B3A.

14. Interposing relays.

15. Local control and annunciator touchscreen (one within each excitation cubicle lineup) excitation system human machine interface panels.

16. Provide new meters and associated wiring for field voltage and field current on the existing unit control panel (C2A).

17. Provide new push-to-test indicators and associated wiring for auto voltage regulator

(AVR) on, AVR off, exciter on, exciter ready, exciter off, exciter at over excitation limit, exciter at under excitation limit, PSS on and PSS off on panel C2A.

18. Provide new exciter regulator mode select switch (43E/90SS) and associated wiring on panel C2A.

J. Connect to the synchronous machine field winding with slip rings.

K. Provide test connection interface for diagnostics of electronic modules critical to excitation system performance (IE a port to allow for direct connection from a laptop for testing purposes).

L. Provide devices for polarizing and establishing initial magnetic flux in field circuit of synchronous machine in response to a speed signal. Field flashing power is available from panel B3A.

2.7. EXCITATION SYSTEM FUNCTIONAL REQUIREMENTS

A. Supply field current required by synchronous machine to meet a specific range of power system operating conditions.

B. Quickly demagnetize synchronous field by maintaining continuous field discharge path through active “crowbar” circuit and discharge resistor in parallel with generator field windings for an adjustable time interval during normal and emergency shutdown.

C. Permit continuous stable operation of the synchronous machine for permissible loading conditions (with unit operating either overexcited or under excited).

D. Provide synchronous machine terminal voltage tolerance under all permissible loading conditions between plus or minus five percent of rated voltage and two percent of rated frequency.

E. Provide high initial response in accordance with IEEE 421.1. SCR bridge current short-time capability not less than short-time overcurrent capability of synchronous machine field windings in accordance with IEEE C50.13.

F. Provide a ceiling voltage TBD by the contractor.

G. Provide rated-load field voltages and currents for transient response when the machine is between 70 and 115 percent of rated synchronous machine terminal voltage.

H. Withstand internal and external faults to synchronous machine, abnormal operation, or emergency operation without damage to excitation equipment or machine’s electrical and magnetic circuits.

I. Prevent excitation system shutdown with unit breaker closed except for catastrophic excitation system failure.

J. Rapidly reach positive and negative ceiling voltages.

2.8. EXCITATION SYSTEM ENCLOSURE/CUBICLE

A. Type: NEMA 12 enclosure for indoor application.

B. Dimensions: Cubicles are to be designed to fit through double door access and include lifting lugs for crane rigging. Reference drawing 545-D-415.

C. Maximum footprint: 37.4” Dx 51.31” W see drawing 545-703-445.

D. Material: Manufacturer’s standard gauge sheet steel.

E. Structural Requirements:

1. Hinged doors for access to internal equipment with top and bottom latches.

2. Adequate louvers for ventilation.

3. Floor mounting frames, if applicable.

F. Designed for bottom entry of control cables and top entry for field power cables.

Provides enough space to accommodate number and size of incoming cables.

G. Provide terminal blocks at shipping splits.

H. Provide dedicated terminal section for external wiring, which can be included in low-voltage control cubicle.

I. Provide separation barrier at interfaces between excitation AC supply breaker, cable entry, instrumentation transformers, and major enclosures to include excitation system, and PPT cubicle.

1. Provides metal barrier between low-voltage and high-voltage compartments (to include the excitation supply breaker).

J. Provide copper ground bar in each cubicle.

K. Install the 87EX and associated test switches in a door on the exciter control cubicle.

1. The PPT protection relay to be a SEL 787-2 Transformer Relay, Part Number 07872XE1A1A9X0X850200, manufactured by Schweitzer Engineering Laboratories, 2350 NE Hopkins Ct., Pullman, WA 99163 or equal.

2. The relay will be installed through the enclosure face so that its display is visible for monitoring. Suitable access shall be provided to perform relay maintenance.

L. Finishes. Use manufacturer standard interior and exterior colors.

M. Accessories:

1. 120 Volt, 60 Hertz, GFCI receptacle mounted in each cubicle.

2. 120 Volt, 60 Hertz, LED lighting fixture mounted in each cubicle and switched automatically with door opening.

N. Provide thermostat-controlled space heaters that prevents moisture condensation inside enclosures/cubicles.

O. Provide enclosures/cubicles capable of maintaining temperature below 104 degrees F.

P. Provide enclosure/cubicle air filters with a Minimum Efficiency Reporting Value

(MERV) rating of 8 as defined in ASHRAE 52.2. Air filter media shall be removable and replaceable.

2.9. SCR BRIDGES

A. Type: Three-phase, full-wave rectifier bridge assemblies.

B. Configuration: Two SCRs per phase, six SCRs per bridge. Powered from excitation transformer.

C. Performance:

1. Short-time thermal overload capability equal to or greater than the rotor winding short-time thermal overload requirements specified in IEEE C50.13.

2. Capable of continuously supplying 115 percent of rated generator field current.

D. Essential Characteristics:

1. Provide redundancy such that failure of one bridge shall not cause shutdown of the synchronous machine or result in reduction of machine capacity; therefore, redundant bridges and firing circuits shall always operate continuously and in parallel to insure bump less transfer to functioning redundant bridges.

2. Provide indication of bridge failure.

3. Rated to incorporate an allowance to cover any loss in capacity due to aging and fault duty.

4. PIV rating of at least 3.5 times peak input voltage for protection against reverse transients.

5. Transient voltage protection for bridge circuit to guard against SCR damage under all operating conditions. If fuses are used, they shall be equipped with blown-fuse indicators that have electrically separate contacts, wired out to terminal blocks.

Provide indication and test points located on circuit boards furnished with SCR bridges.

6. Separate temperature-detecting device in each AC bridge circuit branch with three electrically independent alarm and trip contacts that close when temperature of bridge circuit rises to a preset level. Wire contacts out to terminal blocks for annunciation, supervisory control, and shutdown circuits.

7. Separate firing circuits controlled by voltage regulating equipment if required by manufacturer design.

E. Forced Ventilation System:

1. Design to require no forced ventilation for start-up and off-line operation. Forced ventilation may be activated when synchronous machine is on-line and carrying load.

2.10. FIELD CIRCUIT EQUIPMENT

A. Synchronous machine field current transducer:

B. Having the following essential characteristics:

1. Provide field current transducer output signals for use with new meter on panel C2A and for SCADA.

2. Maintain isolation from ground and field circuit components.

3. Isolation: 2500 volts minimum.

4. Input: 0-100 millivolt shunt which represents 0-800 amperes.

5. Output: 4-20 milli-ampere over impedance range of 0 to 500 ohms without necessary adjustments.

6. Accuracy: Plus, or minus 0.5 percent of rated full-scale dc output, maximum.

7. Field adjustable calibration: Plus, or minus 10 percent of rated output.

C. Provide new field current shunt resistors or other adequate field current sensing devices. Install new shunt on generator field side to show current decay when discharge circuits are active.

D. Synchronous machine field voltage transducer:

1. Having the following essential characteristics:

a. Provide field voltage transducer output signals for use with new meter on panel C2A and for SCADA.

b. Maintain isolation from ground and field circuit components.

c. Isolation: 2500 volts minimum.

d. Input: -600 to 600 volts.

e. Output: 4-20 milli-Ampere output over impedance range of 0 to 500 ohms without necessary adjustments.

f. Accuracy: Plus, or minus 0.5 percent of rated full-scale dc output, maximum.

g. Field adjustable calibration: Plus, or minus 10 percent of rated output.

2. Electronic Discharge Equipment to Discharge Synchronous Machine Field:

a. Active “Crowbar”: Provide controllable semiconductor switch in series with discharge resistor for rapid de-excitation during normal and emergency shutdown of the synchronous machine.

b. Anti-parallel SCRs in semiconductor switch: Provided with appropriate instantaneous ratings to conduct synchronous machine field discharge currents limit only by synchronous machine field winding resistance and discharge resistor connected in series. Force “Crowbar” SCRs to conduct during shutdown via a gate control signal that is independent of field voltage or current gate signal.

c. Provide contacts that close when passive de-excitation is active, wire contacts out to terminal blocks for use with lockout (86) circuits and Government alarm circuits.

3. Synchronous machine field winding temperature:

a. Provide device to calculate field winding resistance from field current and field voltage transducer signals during operation.

b. Display field winding temperature based on the resistance derived from the calculation above on excitation system HMI.

c. Provide analog 4-20 milliamperes output for future use.

d. Provide output for alarming when field temperature rise exceeds 100 degrees

Celsius.

2.11. MEDIUM VOLTAGE RECTIFIER TRANSFORMER

1.01 PERFORMANCE REQUIREMENTS A. Completely assembled and installed transformers shall operate as specified without derating under following conditions:

1. Elevation: [5962] ft.

2. Temperature Range: [-10] degrees C to [40] degrees C.

3. Seismic Qualifications: Meet [High] Qualification level in accordance with IEEE 693.

1.02 QUALITY A. Medium voltage rectifier transformer, voltage transformer manufacturing factory:

1. ISO 9001 certified.

2. Certification provided by independent certifying agency.

PART 2 PRODUCTS 2.01 VOLTAGE TRANSFORMERS

A. Conform to IEEE C57.13.

B. Suitable for base mounting.

C. Suitable for connection to high-voltage power circuits between line and ground.

D. Ratings:

1. Feature: Excitation Step-Down Transformer

2. Type: Three phase, two winding, outdoor, rectifier duty, liquid-filled

3. Capacity: TBD by Contractor

4. Class: KNAN, NOTE: Fire point of insulating liquid must be greater than 300 degrees Celsius.

5. Reverse Power Flow: None

6. Rated Frequency: 60 Hz

7. Impedance: 5.75%

8. System Fault Data (High voltage side): 25 kA symmetrical and X/R = 30

9. Altitude: 6,000 ft

10. Rated Voltage:

A. High: 6.9 kv Line to Line B. Low: TBD by contractor

11. Connection:

A. High: Ungrounded Wye or Delta B. Low: Delta

12. Winding BIL:

A. High: 110 kv B. Low: 30 kv

13. Bushing BIL: NA

14. Taps (de-energized):

A. High: +5%, +2.5%, nominal, -2.5%, -5% B. Low: None

15. On-Load Tap Changer:

A. High: No B. Low: No

16. Surge Arrestor:

A. High: No B. Low: No

17. CT’s: High side only

18. Electrostatic Ground Shield: Yes

19. Winding Temperature Detectors: Yes (RTD)

20. Special Service Conditions: 6,000 ft elevation

21. Inspection windows: Include infrared inspection windows for all three phases front and back

22. Winding Conductor type: Copper

23. Outdoor Operation: Yes

24. Temperature Rise: 130 C

25. Follows IEEE C57.18.10-2021, and C57.12.00-2021 standards

E. Construction:

1. Base housing: Weatherproof construction.

2. Insulation: Gray epoxy.

3. Consist of factory-adjusted elements mounted in base housings.

4. Factory adjust burden watts, burden power factor, voltage ratio, and phase angle.

5. Provide secondary junction box: Weatherproof.

6. Provide ground terminal:

a. Suitable for use with copper grounding cable indicated on drawings.

b. Mount on base of voltage transformers.

F. Secondaries: Two electrically separate secondaries, each capable of supplying voltage at both marked ratios.

G. Accessories:

1. Wire Labels:

a. White.

b. Self-laminating-vinyl type or heat-shrink type.

c. Machine-generated black lettering.

2. Wire Terminals: Manufacturer’s standard insulated ring tongue terminals.

H. Nameplate: Mount on base enclosure.

2.02 CONTRACTOR SOURCE QUALITY TESTING

A. Factory Testing: Routine tests in accordance with IEEE C57.13.

2.12. METERING TRANSFORMER

1. At this time the Bureau of Reclamation will be using the existing metering transformer equipment already installed without the need for a brand new metering transformer per phase at the Kortes power plant.

2.13. VOLTAGE REGULATION EQUIPMENT

A. Type:

1. Digital logic.

2. Continuously acting digital type with solid-state components.

3. Manual (DC) and automatic (AC) control modes.

B. General Description and Operation:

1. Responsive to synchronous machine terminal voltage in automatic mode and be able to initiate corrective action for a sustained 0.1 percent change in terminal voltage.

2. Failure of any control element shall not cause dangerous or uncontrollable operation of the excitation system.

3. Activate alarms under abnormal conditions to warn of impending protective action, including operation of any limiters. Self-resetting alarms if conditions return to normal operating range.

C. Manual (DC) Regulator:

1. Regulate field current (preferred method), field voltage, or firing angles of SCRs.

2. Control range: 20 to 115 percent of rated synchronous machine field current.

3. Designed for synchronous machine testing purposes.

4. Continuously track AVR settings.

D. Manual (DC) Digital Level Reference Adjuster:

1. Can be integral to digital controller.

2. Digital level reference adjuster for smooth (or in steps of less than 0.1 percent) control of synchronous machine output field current between 20 and 115 percent of rated field current at 75 degrees Celsius. Provide rate of change capability between

0.2 to 2 percent per second. Make provisions to permit operating range shifting after adjuster is installed.

3. Adjustable operational range.

4. Be suitable for 125-volt DC operation.

5. Reposition to determined preposition (speed-no-load) voltage setting following load rejections and normal or emergency shutdown of excitation system/synchronous machine:

6. Provide indication for normal preposition for interlock in synchronous machine starting control circuit. Open contacts at intermediate setting and close contacts in generator mode at speed-no-load preposition.

7. Provide indication for maximum and minimum setting. Open contacts at intermediate settings and close at extreme settings.

8. Provide indication to SCADA RTU, WAPA RTU and locally when in Field Current Regulation (DC) and Automatic Voltage Regulation (AC) modes for use with Government equipment.

9. Provide indication of PSS On/Off to SCADA RTU, WAPA RTU and locally for use with Government equipment.

10. Provide indication of AVR Auto/Manual mode selection, Exciter on/off selection and PSS on/off selection to external device such as SCADA RTU, WAPA RTU and Plant Main Control Boards.

E. Automatic Voltage (AC) Regulator (AVR):

1. Automatic Mode:

a. Maintain synchronous machine terminal voltage at a level determined by the position of automatic voltage level adjusters and be responsive to all three phases of machine terminal voltage.

b. Function in a closed-loop feed-back configuration driven by synchronous machine terminal voltage.

c. Provide transient gain reduction or equivalent method for excitation control system.

d. Automatically actuate SCR bridges through firing circuits.

e. Adjustable for fine tuning.

2. Perform following functions:

a. Maintain three-phase synchronous machine terminal voltage regulation within plus or minus 0.5 percent between no-load and full-load at rated power factor and constant generator frequency.

b. After initial synchronous machine terminal voltage rise following any load rejection up to rated load, restore terminal voltage to a value not more than plus or minus 1.0 percent of terminal voltage held before load rejection. Maintain terminal voltage within these limits through the period of machine overspeed up to at least 200 percent of normal speed.

c. Under transient speed conditions, maintain synchronous machine voltage within plus or minus 1.0 percent of the value the AVR was holding before speed change.

d. Permit continuous stable operation of the synchronous machine under control of the AVR or limiters when operating at 1.0 power factor, overexcited or under excited.

e. After temperatures of AVR components have stabilized, slow changes in ambient temperature from 15 to 55 degrees Celsius shall not cause changes in the synchronous machine terminal voltage of more than 0.5 percent.

f. Frequency Response (gain): With synchronous machine operating off-line at rated voltage and speed, closed-loop excitation control system shall be capable of being tuned to produce no more than plus 0.1 dB and minus 3.0 dB of synchronous machine terminal voltage with respect to changes in voltage reference from direct current to 1.0 hertz (used for response tuning).

g. Frequency Response (phase): With synchronous machine operating off-line at rated voltage and speed, closed-loop excitation control system shall be capable of being tuned to produce no more than 90 degrees of phase shift in synchronous machine terminal voltage with respect to changes in voltage reference from direct current to 1.0 hertz (used for response tuning).

h. With synchronous machine operating off-line at rated voltage and speed, closed-loop excitation control system shall be tunable to hold any overshoot in terminal voltage to no more than 10 percent when a step-in voltage reference, equivalent to 2 percent change in terminal voltage occurs.

i. Detect internal and external circuit failure and automatically transfer to standby AVR, or initiate unit trip and shutdown if redundant AVR is not functioning properly.

3. Provide following features:

a. Reactive current compensator: Stabilize parallel operation of synchronous machine with voltage droop compensation or provide additional regulation of transformer high-side voltage with line drop compensation. The polarity of the compensation signal shall be reversible to provide either function with the same equipment.

b. Do not alarm from limiters during normal shutdown.

c. Under-excitation limiter (UEL):

1) Responsive to signals from the PTs and CTs used for the excitation input signals to automatically limit the reactive power absorbed by the synchronous machine under all operating conditions.

2) Have adjustable limiting characteristics to coordinate with synchronous machines under excitation capability curve.

3) Assume control smoothly and maintain excitation in a stable manner that will not cause the unit to trip.

4) Provide remote indication at control board when UEL is in limiting mode.

5) Coordinate with UEP (loss of field).

4. Over-excitation limiter (OEL):

a. Limit over-excitation of synchronous machine under all operating conditions and be coordinated with synchronous machine’s field winding thermal overload capability characteristics specified in IEEE C.50.13.

b. Responsive to synchronous machine field current only.

c. Have adjustable limiting characteristics to coordinate with synchronous machine’s overexcited capability curve.

d. Incorporate inverse time characteristic and instantaneous maximum limit.

e. Assume control smoothly and maintain excitation in a stable manner.

f. Provide remote indication at control board when OEL is in limiting mode.

g. Coordinate with excitation supply/overcurrent protection (OEP).

5. Volts-per-Hertz limiter (HXL):

a. Adjustable.

b. Responsive to both varying voltage and varying frequency.

c. Act through AVR circuits to prevent overheating of the synchronous machine core due to low-frequency operation.

d. Provide remote indication at control board when HXL is in limiting mode.

e. Coordinate with HXP.

6. Generator terminal over-voltage limiter:

a. Separate device from HXL and main controller.

b. Functions directly into firing circuits.

c. Can be integral to firing circuits.

d. Provide circuitry to protect synchronous machine from over- voltage conditions due to regulator malfunction.

e. Be responsive to machine terminal voltage only.

f. Reduce excitation through phase back of firing circuits to decrease terminal voltage.

g. Provide remote indication at control board when overvoltage limiter is in limiting mode.

7. A/D input terminal:

a. Connect to AVR summing junction for testing.

b. Provide bandwidth of at least 10 Hertz.

F. AVR Voltage Level Reference Adjuster:

1. Can be integrated in AVR/digital controller.

2. Digital voltage level reference adjuster shall control smoothly (or in steps of less than 0.1 percent) synchronous machine output voltage between 85 and 110 percent of rated terminal voltage. Rate of change of 0.2 to 2 percent per second. Make provisions to permit operating range shifting after adjuster is installed.

3. Adjustable operational range.

4. Be suitable for 125 Volts DC operation.

5. Provide contact for maximum and minimum voltage setting. Open contacts at intermediate settings and close at extreme settings.

6. Provide contacts for determined normal preposition (speed-no-load) for an interlock in synchronous machine starting control circuit when starting in generator mode. Open contacts at intermediate setting and close contacts at normal preposition.

7. Reposition to normal preposition voltage setting following shutdown of excitation system. Provide indication for preposition, and top and bottom limits (amber light, red and green lights respectively) on unit control board.

G. Power System Stabilizer (PSS):

1. Can be integrated in AVR/digital controller.

2. Type: PSS2B in accordance with IEEE 421.5, dual input type, utilizing both frequency and electrical power input signals simultaneously.

3. Perform following functions:

a. Supplement AVR action by adding a control signal to regulator input.

b. Cause excitation system to change terminal voltage of synchronous machine in proportion to, and in phase with, the machine speed deviation from normal.

c. Synthesize a control signal that represents the integral of accelerating power.

Condition control signal with three adjustable lead time constants, three adjustable lag time constants, adjustable gain, and adjustable washout filter.

4. Provide following adjustable features:

a. Adjustable gain range of at least zero to 100 per unit.

b. Adjustable lead time constants range of at least 0.01 to 10 seconds.

c. Adjustable lag time constant range of 0.01 to 10 seconds.

d. Adjustable washout filter range of 2 to 30 seconds.

5. Provide adjustable limiter for independent limit setting of each polarity signal and to prevent stabilizer signal from exceeding the equivalent of 0 to plus or minus

6. Provide 0.20 per unit change in synchronous machine terminal voltage.

7. Provide devices to automatically remove PSS signals when terminal voltage of synchronous machine exceeds an adjustable level from plus or minus 5 percent to plus or minus 10 percent.

8. Provide low-power cutoff circuit to remove PSS signals from the AVRs.

Adjustable circuit from 0 to 80 percent of synchronous machine real power output.

9. Provide internal frequency calculator.

10. Provide following functions:

a. When control switch is OFF, PSS is not in service regardless of unit breaker position.

b. When control switch is ON, PSS is placed in service automatically when unit breaker closes, and the active power level is above the low power cut- off point; it is switched out of service automatically at low power cutoff point or when unit breaker opens.

11. If PSS is not integral to AVRs, provide suitable equipment to automatically remove PSS signal to AVRs under conditions of PSS malfunction. Mount equipment in regulator cubicle. Provide PSS with an electrically isolated, normally open contact that closes when PSS malfunctions or is disabled.

12. PSS testing and calibration requirements:

a. Arrange outputs of speed (or internal frequency) transducer, watt transducer, and PSS for connection to D/A outputs for testing.

b. An A/D input for connection before phase compensation stage is required for testing with a bandwidth of at least 10-hertz.

c. Verifiable frequency and watt transducer calibrations. Removable transducer circuits from PSS circuits for AVR compensation testing. Removable PSS output to the summing junction of the AVR.

d. Adjustable key PSS parameters to facilitate field adjustment and calibration.

Calibration units shall relate to actual parameter's engineering units, and output limiters shall have individually adjustable maximum and minimum parameters.

2.14. HMI TOUCH SCREEN

A. Color touch screen on exciter cabinet displaying excitation and generator information, changing of system parameters, and selecting control modes and setpoints.

B. Size: 12-inch minimum (diagonal).

C. Resolution: 800 X 600 minimum.

D. Screen: Color.

E. Sensing: Capacitive or Resistive.

F. UL listed.

G. Includes the ability to inhibit or force inputs and outputs H. Functionality for existing monitoring and control board functions will remain the same as shown on reference drawings.

2.15. DATA LOGGING (OSCILLOGRAPHY) AND SCADA INTERFACE

A. Displayed on HMI.

B. Provides the capability to monitor the following quantities:

1. Terminal voltage, Vt.

2. Megawatts.

3. Megavars.

4. Generator Field voltage, Vfd.

5. Generator Field current, Ifd.

6. Phase Current, Iep.

7. Frequency.

8. Limiter status.

9. Test input.

10. Generator field temperature.

11. Excitation supply breaker closed/tripped.

12. Excitation field breaker closed/tripped.

13. PSS enabled.

14. PSS bypassed (low-power cutoff, rough-zone operation, or under/over voltage).

15. Excitation off.

16. Excitation in regulate mode (AVR/FCR).

17. PF control mode.

18. VAR control mode.

19. Bridge alarm (fans, power supply, and SCR temperature).

20. Loss of Regulator PTs.

21. Loss of Metering PTs.

22. Loss of primary DC control power.

23. Loss of backup AC control power.

24. PPT overtemperature alarm.

25. PPT overtemperature trip.

26. Failure to flash.

27. Excitation supply/Overexcitation protection time out trip.

C. Complies with Western Electricity Coordination Council (WECC) SCADA and annunciation requirements.

D. Minimum sampling rate: 100-hertz.

E. Event Recording:

1. Provide time and date stamped event records stored in non-volatile memory.

2. Display current time.

F. IRIG-B compatible.

G. SCADA communications:

1. Modbus TCP/IP interface with register map that contains real time input and output addresses.

2. Capability to control:

a. Excitation voltage level adjust RAISE/LOWER.

2.16. Instrument transformers

A. CTs to be new equipment in exciter cubicle.

1. One CT per phase.

2. Conform to IEEE 57.13

a. Feature: CT’s for SEL-787 relay

1. Location: PPT HV Side – Relay CT Location: PPT enclosure, High side of transformer Connected Device: SEL 787 Relay Nominal System Voltage: 0.6 kV System Frequency: 60 Hz

BIL Rating: 10 kV, NOTE: Window type CT to be used around insulated equipment, BIL rating is not required.

CT Ratio: 3Y-50:5, NOTE: CT ratio and accuracy class is only applicable if the PPT is sized below 300 kVA for nominal transformer voltages of 6.9 kV and 350 V.

Accuracy Class: C20 (minimum) Short Time Mechanical Rating: 67.5 peak kA Short Time Thermal Rating: 25 sym kA Thermal Rating: 1.0 at 55 C

2. Location: PPT LV Side – Relay CT Location: Excitation Cubicles – load side of excitation supply breaker Connected Device: SEL 787 Relay Nominal System Voltage: 0.6 kV System Frequency: 60 Hz

BIL Rating: 10 kV, NOTE: Window type CT to be used around insulated equipment, BIL rating is not required.

CT Ratio: 3Y-600:5, NOTE: CT ratio and accuracy class is only applicable if the PPT is sized below 300 kVA for nominal transformer voltages of 6.9 kV and 350 V.

Accuracy Class: C100 (minimum) Short Time Mechanical Rating: Consistent with short circuit ratings of LV equipment Short Time Thermal Rating: Consistent with short circuit ratings of LV equipment Thermal Rating: 1.0 at 55 C

B. PTs to be new equipment in exciter cubicle.

1. One PT per phase.

2. Conform to IEEE 57.13

a. Feature:

Location: Unit Terminals Rated Voltage: 7,200 V Configuration: 3Y - 7200:120 V Marked Ratio: 60:1 BIL Rating: 110 kV Frequency: 60 Hz Accuracy Class: 0.3 W,X,M,Y,Z, 1.2 ZZ Thermal Burden Rating: 1000 VA @ 55 C

2.17. METAL-ENCLOSED INTERRUPTER SWITCH

3. Feature: Load Interrupter switchs on 6.9 kV side of excitation transformer

4. Nominal System Voltage: 6.9 kV

5. Rated Maximum Voltage: 15 kV

6. Rated Power Frequency Withstand Voltage: 36 kV

7. Rated Lightning Impulse Withstand Voltage: 110 kV

8. Rated Frequency: 60 Hz

9. Rated Continuous Current: 600 A

10. Rated Load-Switching Current: 600 A

11. Rated Short-Time Withstand Current: 25 kA – NOTE: 2 second withstand time

12. Rated Peak Withstand Current: 65 kA

13. Special Service Conditions: 6000 ft Elevation, NOTE: Switchgear is being installed above 3300 ft, which is an unusual service condition per IEEE Std C37.20.3

14. Fused Switch: Yes, NOTE: See Fuse Recommendations below

15. Conforms to IEEE C37.20.3-2023, and C37.20.4-2013, includes an integral switch and fuse.

2.18. FUSES

A. Feature: Fuses for Metal-Enclosed Interrupter Switches

1. Nominal System Voltage: 6.9 kV

2. Rated Maximum Voltage: 15.5 kV

3. Rated Current: TBD by Contractor

4. Maximum Interrupting Current: 25 kA RMS symmetrical or 40 kA RMS asymmetrical. NOTE: Values correspond to R10 series of preferred numbers as seen in IEEE C37.41-2024.

5. Rated Frequency: 60 Hz

6. Special Service Conditions: 6000 ft Elevation, NOTE: Switchgear is being installed above 3300 ft, which is an unusual service condition per IEEE Std C37.20.3

7. Conforms to IEEE C37.41-2024

2.19. INTERFACE AND UPGRADE OF EXISTING CONTROL CIRCUITS, DEVICES

AND REMOTE MONITORING AND CONTROL BOARD

A. Design control circuits to interface to and operate with remote panel C2A devices.

B. Contacts suitable for 125 Volts DC operation.

C. Exciter voltage control switch (70CVCS):

1. Handel positions: 2 positions, plus and minus 45 degrees from top-center.

2. Handel type: Oval.

3. Rotating action: Spring return to center.

4. Nameplate engraving: EXCITER VOLTAGE CONTROL.

5. Nameplate engraving: RAISE and LOWER.

D. Exciter Regulator Mode Select Switch (43E/90SS)

1. Handle positions: 2 positions, plus and minus 45 degrees from top-center.

2. Handle type: Oval.

3. Rotating action: Maintaining all positions.

4. Nameplate engraving: EXCITER REGULTAOR MODE SELECT SWITCH

43E/90SS

5. Position engraving: AUTO and MANUAL.

6. Indicating lights:

E. PSS on/off control switch (169PSS):

1. Handle positions: 2 positions, plus and minus 45 degrees from top-center.

2. Handle type: Oval.

3. Rotating action: Maintaining all positions.

4. Nameplate engraving: PSS ENABLE 169PSS.

5. Position engraving: ON and OFF.

6. Two normally open contacts when in the off position for SCADA position status.

7. Indicating lights:

a. PSS ENABLED: Red light indicates PSS is Active.

b. PSS DISABLED: Green light indicates PSS is disabled.

c. Amber light indicates PSS bypassed due to an over-voltage or under-voltage condition on synchronous machine terminals.

F. Include a contact wired out to terminal blocks to indicate the regulator is in service when the synchronous machine is in any mode.

G. Coordinate outputs or signals of new excitation systems with new metering instruments (synchronous machine field Amperes, and field Volts) in unit/main control boards.

H. Provide contacts for interfacing excitation system startup and shutdown with the unit controls to duplicate the functions as shown in informational excitation schematic drawings.

2.20. REMOTE CONTROL BOARD FIELD CURRENT AND VOLTAGE METERS

A. Digital bar graph field current and voltage meters.

B. Size: 4.5-inch square.

C. 5-digit digital display.

D. Input type: 4-20 milliampere.

E. Retransmit: 4-20 milliampere isolated source.

F. Power: 125 volts DC.

G. Peak/Valley hold.

H. Red LED color.

2.21. REMOTE CONTROL BOARD INDICATING LIGHTS GENERAL

REQUIREMENTS

A. Provide control circuit for operation of indicating lights. Do not use contacts from related switch to operate indicating lights.

B. Having the following essential characteristics:

1. Push-to-test, LED type, 135 volts DC.

2. Lens color as shown or red, green, or amber as required.

3. Digitally driven.

2.22. NAMEPLATE GENERAL REQUIREMENTS

1. Material: Laminated plastic.

2. Color: Black, engraved to white core.

3. In accordance with standard drawings.

4. For internal devices mounted within equipment enclosures, instead of furnishing nameplates, each device may be identified with the device name or standard NEMA or IEEE designation by a permanent marking on or adjacent to the device.

2.23. CABLE, WIRING AND CONNECTIONS

A. Suitable for installation in cable trays and conduit, for direct burial, and for general use.

B. XHHW insulation on individual conductors C. Multiconductor control cable will have:

1. A binder tape or jacket covering

2. Shielding conforming to NEMA WC 57

3. Overall flame-retardant covering (jacket) of thermoplastic or neoprene

D. Minimum 14 AWG.

E. Provides material and drawings to make connections to devices external to the exciter.

F. Provides barrier in cubicles between circuits utilizing 240 Volts or greater and lower voltage circuits.

G. Connects internal and external wires of different voltages to separate terminal blocks.

H. Provides interposing auxiliary relays for each distinct output contact voltage.

I. Routes control and power cable for internal devices, requiring connection to external equipment, to terminal blocks.

J. Provides ring connectors for wire terminations. Provide ferrule connectors where use of ring tongue connectors is not practical, such as terminations at selector switches, auxiliary relays, LED lights, pushbuttons, and other similar devices.

K. CABLES:

1. Feature: Cables from generator terminals to PPT

a. Location:

Generator terminals to interrupter switch:

1. Rated for 14 kV

2. -3-1/C-500 kcmil Cu, conductor size

3. MV-105, Temperature Rating (C)

4. Referenced from, NEC Table 315.60 Table 11 – three circuits @ 105 degrees C.

Interrupter switch to PPT:

1. Rated for 14 kV

2. -3-1/C-500 kcmil Cu, conductor size

3. MV-105, Temperature Rating (C)

4. Referenced from, NEC Table 315.60 Table 11 – three circuits @ 105 degrees C.

IMPORTANT NOTES:

1. 500 kcmil cable size is recommended to withstand available fault current, the ampacity of this cable will likely exceed the expected full-load current of the PPT.

2. Cable should be shielded, single-point grounded, and properly terminated for use on a 6.9 kV system.

2.24. TERMINAL BLOCKS

A. Interface terminal blocks:

1. Provide for external wiring (circuits leaving excitation cubicles).

2. Organize external…