A Distance Relay Having Quadrilateral Characteristics

摘要

1,164,542. Protective arrangements. MEIDENSHA ELECTRIC MFG. CO. Ltd. 10 April, 1967 [11 April, 1966], No. 16322/67. Heading H2K. A distance relay arrangement having quadrilateral characteristics comprises replica impedances Z 1 . . . Z 6 of which the impedances Z 5 , Z 6 may be at least partially common to individual ones of the other impedances, means for generating voltages e 1 . . . e 6 which are equal to IZ 1 -V, IZ 2 -V, V-IZ 3 , V-IZ 4 , IZ 5 and IZ 6 respectively where I and V are the current and voltage of the protected line and the vector voltages IZ 1 to IZ 4 are situated on extension lines of a parallelogram which determines the zone to be protected, and means for detecting by phase comparison whether or not voltages e 1 to e 4 lag vector voltages 6 5 while leading vector voltage e 6 . Fig. 5 shows the arrangement for producing the voltages l 1 to l 6 , this arrangement comprising potential transformers PT1 . . . PT 4 , current transformers CT1 ... CT4 and replica impedances C1, R1; RSP1/SP2, R2, L2; C3, R3; and C4, R4. The voltages may be applied to a relay circuit or converted to rectangular pulses and applied to a logic circuit.