Hi, I am trying to simulate protection of distribution lines in a microgrid using differential current relays.
Hi I am trying to simulate the protection of distribution lines in a microgrid, using differential current relays. I have connected multimeters at both ends of the line. I am inputing the RMS current from the multimeters to the differential current relay. My problem is the relay is issuing a tripping signal without any differential current. What could I be missing? How is the current differential relay connected?
Attached is a capture showing Is_R3A and Is_R4B respective RMS currents from both ends of the line. The other capture2 attachment shows PH_R3A and PH_R4B which are the respective phases. Diff_OP is the output from the differential relay and Idiff is the difference between Is_R3A and Is_R4B. Kindly assist.
I'm not sure if I've done the right thing, instead of using CTs, I thought of using multimeters, i have done this with overcurrent relays and it works well. Thought of doing the same with differential current relays, i am using the RMS current and the corresponding phase measurement from the multimeters as my input to the differential current relay in PSCAD library. I am not sure if it is the correct implementation. How do you implement differential current relays using multimeters?
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Are you sure about your differential current relay implementation?
Did you implement differential current relay correctly?
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I'm not sure if I've done the right thing, instead of using CTs, I thought of using multimeters, i have done this with overcurrent relays and it works well. Thought of doing the same with differential current relays, i am using the RMS current and the corresponding phase measurement from the multimeters as my input to the differential current relay in PSCAD library. I am not sure if it is the correct implementation. How do you implement differential current relays using multimeters?
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