Self-adaptive Positive-sequence Current Quick-break Protection Method for Petal-shaped Power Distribution Network Trunk Line

摘要

The invention relates to a self-adaptive positive-sequence current quick-break protection method for a petal-shaped power distribution network trunk line. The method comprises the following steps: step 1, calculating a positive-sequence voltage phasor and a positive-sequence current amplitude at a protection installation position when a fault occurs, acquiring and storing a positive sequence impedance value of a protected line; judging a fault type, and judging a fault direction; step 2, when a fault direction element judges that a fault occurs in the forward direction, selecting a self-adaptive current quick-break protection setting formula according to the fault type, and when positive sequence current measured by protection is larger than a protection setting value, judging that the protected line has a short-circuit fault, and making a circuit breaker trip quickly. Compared with the prior art, the method provided by the invention has enough sensitivity and does not change along with the change of the line length and the system operation mode.