Protection Settings Verification And Analysis System For Subtransmission Systems

The operation modes of a sub-transmission system are flexible and variable. When the operation mode changes, the protection setting used online maybe do not meet reliability and selectivity, which is difficulty found by protection engineers. Once a fault occurs, the unreasonable settings value may result in false action of relays, consequently will result in a large-scale blackout accidence. In order to find out the errors in protection settings online, we develop protection setting verification and analysis system of sub-transmission systems. By scanning the circuit breaker status from SCADA, the system does the topology analysis for the studied electrical network, makes out the protection coordination for verification the settings of the phase-to-phase distance relays, grounding distance relays and zero-sequence current direction relays according to the official, The system outputs the verification results and their interpretation.