PPL EU Relay Standardization

Transcription

1 PPL EU Relay Standardization John Sonnelitter Senior Engineer, Transmission Relay Engineering Richard Michael Jr. Support Engineer, Transmission Relay Engineering 9/18/2018

2 Background PPL EU is undergoing major capital investment at our transmission substations, contractor engineering firms have been hired to assist with accomplishing our business goals A challenge that has come up is the quality of the engineering packages One of the findings was that there s significant complexity in our protection/control standards (particularly with our breaker control relay) Follow-up was a review of our schemes to understand opportunities to simplify Validated our approach against some industry references/benchmarks 1

3 Existing PPL Breaker Control Philosophy We implement an automatic bus restoration scheme The intent is to restore a 230KV, 138KV, or 69KV bus after a fault on the bus Includes normal and alternate test sources This introduces an incredible amount of logic for something that isn t needed due to the topology of our new stations Scenario 1: 2: 3: Bus Diff Permanent Momentary Fault Normal Test Source: Transformer Unavailable Low side CB Alternate Test Source: Bay 1 Line CB

4 Existing PPL Breaker Control Philosophy Automatic CB isolation via MOD controls Scheme is designed to automatically isolate the failed breaker by breaker MOD s and restore bus Creates more complexities in relay logic for a rare scenario and failed breaker can be remotely isolated via SCADA controls 3

5 Future PPL Breaker Control Philosophy Simplified Breaker Control Relay Logic (BF Only) BF Initiates CB/BF Trip 50FAN 4

6 PPL RE Standard Simplification Idea s 1. Simplify Logic Simplify number of functions in the breaker control relay 2. Remove Mimic Bus Mimic bus takes up a large control panel footprint and limits placement Removal allows more compact layouts and simplified relay replacements. 3. Consolidate Panel Layout Control handles, primary relays, and backup relays, are currently segregated into different panel lineups, requiring significant control house space and complicating replacements Consolidating functions into a duplex panel design allows more compact layouts and simplified relay replacements. 4. Remove Bus Testing This simplifies controls in relay and thus designing/testing/commissioning. 5. Simplify MOD Control Motor-Operated Disconnect (MOD) controls are used during CB failure to isolate CB and conduct bus testing. Automated controls are built into relay logic currently, however logic is complex and CB failure is rare 5

7 Relay Standardization and Transmission Protection Philosophy Documents

8 Precursors to Relay Standardization Lack of EM Standards 12.5Ω 19.5Ω Line A 10Ω Line B 10Ω 2200A 2.5Ω 9.5Ω Zone 1 = 9Ω INSTANTANEOUS OP TIME Zone 1 = 9Ω INSTANTANEOUS OP TIME Zone 2 = 12.5Ω DISTANCE REACH= 22Ω OP TIME 0.5s DEPENDENT OP TIME ON TOC with 600PA Pickup, MI Curve, TDS=2.0 Time Current 7

9 Precursors to Relay Standardization Lack of EM Standards X X Z2 Z3 Z2 Z1 70⁰ R 8Ω 7.71Ω 70⁰ Z1 R Z1 = 8Ω Zf = 70⁰ Zfx = 8.2cos(90-70)=7.71Ω MHO CHARACTERISTIC REACTANCE (OHM) CHARACTERISTIC 8

10 Precursors to Relay Standardization Lack of EM Knowledge Base for Newer Engineers 9

11 Standardized Relays & Relay Elements Decided on a standard set of primary and backup relays for every piece of equipment on our system Decided on a standard set of protection elements on each relay which will be employed for all installations. Relays are all from the same manufacturer. 10

12 Transmission Protection Philosophy Documents 11

13 Transmission Protection Example Documents 12

14 Overall Benefits to Relay/P&C Standardization Consistent and simpler design standards to help better control quality of engineering packages Testing & Commissioning of equipment will be easier and more effective Can onboard new employee s & contractors in less time 13