| 摘要 |
11RCO4716 OUT-OF-STEP BLOCKING UNIT An out-of-step blocking unit of a protective relay for detecting faults in a three phase alternating current electrical power distribution system utilizes restraint signals in conjunction with an operating signal to generate a net operate signal as a restraint to the relay in order to prevent operation of circuit breakers associated with the relay as a result of load swings in the power distribution system. The restraint signals include a signal related to a negative sequence component of current flowing in the distribution system; a signal related to a zero sequence component of current flowing in the power distribution system; and a signal related to a .DELTA. (IZ-V) quantity which is the difference between fault and prefault values of the quantity (IZ-V). |
