Reactor Differential Protection Stability & Sensitivity Test.

Testing the stability and sensitivity of Reactor Differential Protection (87R) is crucial to ensure that the protection scheme operates reliably under various operating conditions and can accurately detect and discriminate between fault and normal operating conditions.

This article is to guide the responsible persons in conducting Reactor Differential Protection stability & sensitivity test and procedures.

Test Equipment: 3 phase AC Generator kit, Clamp Meter and Phase Angle Meter.

Safety Precautions: The following Safety precautions shall be taken in consideration prior, during and after conducting the test measurements.

• Safety tagging shall be implemented.
• Isolate the Area by Safety Warning Tape.
• Keep a Safe Distance from the device being tested.
• Wear Appropriate Personal Protective Equipment(PPE) Prior to starting any testing activity.
• Implementation of Proper Grounding.

Reactor Differential Protection Stability & Sensitivity Test.

Here’s a detailed guide on how to perform stability and sensitivity tests for Reactor Differential Protection:

ADDITIONAL SAFETY PRECAUTIONS BEFORE PERFORMING THIS TEST:

1.) LOCKOUT RELAY should be isolated and ensure NO POSSIBLE tripping during the test
2.) Check that any high impedance protection is shorted before primary injection on their CT Cores.
3.) Any CT cores not related to Transformer protection should be shorted for safety.
5.) Isolate the Differential Protection Trip Links
6.) The injected current should not exceed the smallest turns ratio CT.
7.) Check the balance and phase sequence of the three phases power supply.

1. Perform General Visual Inspection as per Work Instructions.
2. The final settings must be applied and tested before the stability test.
3. Check that all associated CT cores are having the same Knee point for high impedance protection.
4. For Reactor Differential Stability Test for 3 Phases.

5. For Reactor Differential Sensitivity Proceed testing Test Swap 3 phase of CT Polarity.

6. Normalize the reversed CT.
7. Normalize the trip isolation links.
8. Normalize the shorted CT cores.

TEST RESULTS AND ACCEPTANCE VALUES.

The results of testing the Reactor Stability should match what is expected as per the design and implementation of the Reactor Scheme.

By following above guidelines and conducting thorough stability and sensitivity testing, you can ensure that the Reactor Differential Protection scheme operates reliably and effectively, providing robust protection for the power system and its assets.