Testing and Development Activities of Meter-Base Switches for DER Applications Power Systems 2005 Conference, Clemson University March Panel Session on Interconnection: Doeg RodriguezTom Key Univ. of Puerto RicoEPRI Solutions Mayagüez, PRKnoxville, TN (787) (865)

2 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Update on EPRI Meter-Base Switch Developments  Evaluation of Global Power Products “Generlink” (previously PEPCO Technologies)  Physical Inspection of the unit (inside and outside)  Transfer, Protection and Time Tests  Adding Paralleling Functions….”GridGateway”  Programmable Protection Settings  Future for AMR, Communications and Dispatching

3 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Generlink Unit Tests  Revenue Meter collar  Specially designed plug - prevents accidental disconnection or operation

4 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Top side view  Compatible with 4-jaw ringed/ring-less bases  CT’s on Utility side  Load circuit breakers on generator side  Generlink Plug

5 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Side view  Weather-tight cap  Meter base ring  Indicator LEDS  Utility Availability  Internal Fault  Overload  Generator as preferred source

6 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Bottom view  Blades for meter base  Neutral bond for generator  Meter base ring

7 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Switching Components Interlocking relays  200 A rated busbars  200 A rated utility relay  30 A rated generator relay  Integral protection functions

8 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Test Setup The “House”  PT and CT monitoring points  Weather-head  Meterbase  Circuit Panel

9 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Test Setup (Cont.)  Service Entrance  150 FT 4/0 AWG  50 kVA Transformer 480/240/120

10 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Test Setup (Cont.)  Standby source  25 kVA Transformer  480/240/120 V  Heater loads (×2)  4300 W (240V)  5200 W (240V)  120 V loads (×2)  40 W bulbs

11 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. State Diagram / Singleline  Generator is preferred source  Allows for scheduled maintenance and test runs  Transfer is break-before-make  Relay operation is fully interlocked

12 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Tests  Three types  A. Transfer Tests (16 tests)  Voltage Magnitude & Ramp tests  B. Protection Tests (5 tests)  Overload  C. Time Trial Tests (4 tests)  Transfer Time tests

13 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. A. Transfer Tests  Type of tests  Loss of Phase (only one 120V leg)  Under and Over-voltage events  Loss of utility  Paralleling

15 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. B. Protection Tests  Overload temperature trip  Tested onboard generator side load breakers  Inrush compatibility  Verified load breaker coordination with sudden current increase  Overloaded transfer test  Verified GL did not transfer to generator on overload

16 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Protection Tests (Cont.)

17 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Time Trials  Transfer time from Utility to Standby  Standby Source: 25 kVA Transformer  Standby Source: 5 kW Gas Generator  Transfer time from Standby to Utility  Standby Source: 25 kVA Transformer  Standby Source: 5 kW Gas Generator

18 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Time Trials Results Utility to 25 kVA Transformer Orange Unit = 14.2 Cycles (top) Blue Unit = 15.2 Cycles (right)

19 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Time Trials Results Utility to 5kW Generator Orange Unit = 14.0 Cycles (top) Blue Unit = 14.8 Cycles (right)

20 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Time Trials Results 25 kVA Transformer to Utility Orange Unit = 75.5 Cycles (top) Blue Unit = 76.7 Cycles (right)

21 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Time Trials Results 5 kW Generator to Utility Orange Unit = 75.0 Cycles (top) Blue Unit = 75.9 Cycles (right)

22 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Utility House Meter DG GenerLink™ Basic GenerLink

23 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Basic GridGateway Utility House Meter DG GridGateway™ CT 200 A 30 A GridGateway™

FCG ICE Disconnect Switch Disconnect Switch Internal Relay Interface Board Optional External Generator Relay Surge Protection Board Connector for Generator What It Is A device that provides a gateway connection with programmable protection for on-site generation systems operating in parallel with the grid or operating as an island Benefits Represents DG Interconnection Agreement btw end-user & utility Utility adjustable protection parameters Ability to periodically test and validate these parameters Future utility communications and monitoring capability 7 GridGateway Development Any DER Connector for Generator Programmable Control Board

25 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. GridGateway Related Interface and Controls

26 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Example Programmable Trip Settings (GridGateway to have 18 programmable protective functions) The primary functions of the device are to provide protection for the utility from incorrect operation of the DR and to provide a means for safely interconnecting a synchronized DR to the Utility/Residence circuit.

27 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Set up and Functional Control Responsibilities The GG handles any normal switching or paralleling functions, e.g. transfer, MBB or BBM, etc. Utility will use the laptop communication port and set up based on the application and input form end user. If end user changes the DG or Application utility reconfigures. End user has control to select "utility preferred" or "generator preferred," and can lockout either source via local circuit breakers. Eventually control wiring will be required between the GG and the DG for voltage regulator and governor control following standards for parallel interconnection. Potential for external supervisory control via GG, such as generator dispatch or load shedding is considered in the logical design.

28 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. GridGateway Applications Basic manual transfer 0. Basic manual transfer – starts with primary source closed, as default configuration for troubleshooting the unit (no protective functions) Open transition transfer 1. Open transition transfer - follows the Generlink functionality (break-before-make operation) Closed transition transfer 2. Closed transition transfer - momentary paralleling in the range of 1 to 5 seconds for uninterrupted transfer applications (make-before-break operation) Parallel operation rotating 3. Parallel operation rotating generator - GG executes parallel connection, future synchronizing Parallel operation inverter 4. Parallel operation inverter generator - GG allows inverter to synchronize and execute parallel connection

29 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Application State Diagram No Connection Operating State Load on DG Operating State Paralleled DG and Utility Operating State Load on Utility Operating State 2. Close DG Relay 1. Close UtilityRelay 7. Open Utility Relay 6. Open Utility Relay 5. Open DG Relay 4. Close Utility Relay 3. Close DG Relay 8. Open DG Relay

P,Q AMR Applications 0 through 4, Monitoring & Firewall Functions DG Utility L.M Digital I/O lines (Future) for price signals, demand response, dispatching, etc 5 outputs for future load management IO Future governor regulator control Microswitch for selection of preferred source Relay Communication interface for remote meter-reading, load control, etc Metering Chip Residential Load CT CT for DG power measurement GUI (Utility-access only) for Configuration, setup and Debugging Future Current Gateway Functions and Features

Logic Circuit Block Diagram

GUI Tree

33 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Residential Test Set up 200 A/240V Service and Various DG Residential Load Simulator Controllable 12kW Class D Amplifier for Simulation of utility and DG sources

34 Copyright © 2005 EPRI Solutions, Inc. All rights reserved. Future Development Areas AMR Capability DG power measurement Green power sell-back measurements Log and local storage for 15-minute energy samples Protection functions (Current Monitoring) DG over-load protection Lose of a source and reverse power protection Communication 2-3 channels for real-time communication with Utilities, markets etc for economic operation, energy pricing, demand response etc Weather related warnings, maintenance/outage management Load Management Low-voltage outputs to control domestic load