Synchronous Measurement, Control, & Protection of Electric Power Systems. Dr. Edmund O. Schweitzer, III February 29, 2012

Transcription

1 Synchronous Measurement, Control, & Protection of Electric Power Systems Dr. Edmund O. Schweitzer, III February 29, 2012 Copyright SEL 2011

2 The Future of Power Systems No Blackouts New Sources Better Control Faster Tripping Islanding State Measurement Distributed Generation Intermittent Sources Innovations Fast Remedial Action Wide-Area Control Secure Solutions must be: efficient, low-cost, robust, reliable

3 Building Blocks and Solutions Measure, control, protect Process information anywhere Dependable, deterministic, secure communications utility rated Reliable, redundant precise time Real-time wide-area solutions for control, protection, and automation of electric power systems

4 Synchronous measurement, control, and protection capabilities are in your relays, meters, VRCs, TODAY, for free.

5 SEL Synchrophasors Are Everywhere, and Growing Every Day! Western Interconnection >40,000 units Eastern Interconnection >125,000 units Texas Interconnection >18,000 units

6 RTAC & SVP: Relay-Speed Processing, Anywhere State Equations: Stability, Thermal Phasor Math: Self-Checks, Interpolation

7 Generator relays will directly measure δ Z + δ - E V, I a S a ' Generator N E δ IZ V

8 Rotor δ Test System

9

10 Communications for Critical Infrastructure Secure, 5ms healing, reliable, redundant, 0.5µs absolute time, deterministic ms ms 12 ms

11 Relay SVP ICON SVP Relay t E t E t E SVP PMU

12 Radios for POTT and Network Backup Network RTAC X RTAC RTAC Radio Radio Radio Radio Relay Relay Relay Relay

13 GPS Time Is Not Guaranteed! Jamming or interference (NAVWAR) Equipment failure DoD Control Solar flares On December 6, 2006, a solar flare created an unprecedented intense solar radio burst causing large numbers of receivers to stop tracking the GPS signal. -- NOAA Press Release

14 Reliable and Redundant Precise Time Satellites: GPS is great when available ICON networks +/- 0.5µs of all nodes with or without GPS Rubidium and cesium standards WWVB? You can build systems today that enjoy the precision of GPS and provide wide-area synchrony even when GPS is lost.

15 We Must Operate, Control, Protect Our Wide-Area Systems Better Quicker loop times Cycles or seconds vs minutes Automation / operators State-based control Measure the state Drive the system to desired state Distributed control/successful islanding

16 CFE (Mexico): Generation Shedding 400 kv 400 kv National System A3130 A3030 A3T MW Chicoasen (MMT) Sabino (SSB) Angostura (ANG) Tapachula City 400 kv 115 kv Network Southern Region Load Synchrophasors

17 Georgia: Tiblisi Relies on Enguri Dam Line Loss Requires Load Shedding Enguri HPP Copyright SEL 2011

18 Florida Power & Light Anti-islanding T Angle Frequency Slip Acceleration SVP Relay Relay DG

19 Directly Measure the State V 1 Network Synchronized Data V 2... V n Sub 1 Sub n Detect bad data RTAC... SVP Average measurements V 1 Determine topology V n Calculate V at adjacent stations: V = V + ZI

20 Complete State Vector, S Every Location Gets the State Vector Lateral Communications: ICON, Radio V j V k V l = S V m V n V 1. V j = V k V l V m V n V j j k l m n... N = j + k + l + m + n

21 State Interpolation or Linear Estimation Line 4 Line 1 V L4 Sub 1 V L1 Z 12 I 1 V 2 Sub 2 V L3 Line 3 V L2 Line 2 V 1 = ¼ V L1 + V L2 + V L3 + V L4 if all breakers closed and if all voltages about the same V 2 = V 1 + Z 12 I 1

22 Determining Wide-Area Voltages Use Local V and I to Determine Remote V V2 = V1 + Z12 I12

23 Voltage Stability Assessment System SVP Computer Time Alignment Voltage Collapse Prediction Visualization and Control Automatic Control PMUs Major Interconnection Weak Buses Eskom Network

24 Governor Mode Control Utility Power System Plant Distribution System Abbott Generator Relay Frequency and Angle Measurements Across Relay-to-Relay Logic Communications Relay Regulate Power Regulate Frequency Generator Governor

25 Traditional Control to Isolate Line Master Control Bus 1 Bus kv kv Tap Down Close Cap

26 Synchronous Recipes Execute Sent Control to Local at Precise to Controllers Isolate Instant Line Local Control Master Control Local Control Execute Recipe Simultaneously Bus 1 Bus kv 224 kv Tap Down Close Cap

27 Conclusions Measurement, control, protection Dependable, deterministic communications Reliable, redundant precise time Distributed state and vector processing Demand-driven solutions are emerging Soon we will see traditional SCADA replaced by fast, distributed, automated, synchronized measurement & control.