摘要 |
Protective relay apparatus for providing a compensated fault impedance measurement for the determination of a better estimate of fault location along a transmission line is disclosed. In a power system network including local and remote generating sources disposed at respective ends of a transmission line segment of the transmission line, the protective relay apparatus is disposed at the local end of the line segment to measure the fault impedance for use in determining fault location. However, load flow conditions rendered by the generating sources interact with a fault which contributes resistance substantially to the fault impedance of the transmission line to cause an erroneous component in the fault impedance measurement rendering the determination of an erroneous fault location. The protective apparatus disclosed generates a signal as a measure of this erroneous component and compensates the fault impedance measurement as a function of the erroneous component signal, a predetermined impedance characteristic of the transmission line segment, and the fault impedance measurement to provide the compensated fault impedance measurement. |