| 摘要 |
In a distance relay of the kind where defects are detected at 1A, 1B, 1C and, in response, signals VF, ZR IF and VH are produced at 7 from line voltages and currents VA, VB, VC, IA, IB, IC and in turn operating vector EOP and reference vector EPOL are derived to produce at 6 a protection signal 6a, it is arranged that a phase shifter (8) connected to the input of a phase discrimination circuit (16) shifts the phase of VH by the same predetermined amount for all kinds of the defects, on any line. <IMAGE> |
