A method and apparatus for detecting a discontinuity or irregularity in a neutral return line of an electrical power network

摘要

585194 An apparatus and a method for detecting a discontinuity or irregularity in a neutral return line of an electrical power distribution network including the neutral return line, an active line and an earth return are disclosed. The apparatus includes means for measuring voltage change during time intervals associated with a deliberate switching of a known impedance in the electrical network. The voltage change includes a change due to a discontinuity or impedance irregularity in the neutral return line; The apparatus also includes means for implementing an algorithm for identifying the discontinuity or impedance irregularity in presence of allowable variations in nominal supply voltage to the electrical network including voltage changes resulting from network operations that mimic or hide a discontinuity or impedance irregularity in the neutral return line and means for comparing a result of the measuring with a reference to provide an indication of the discontinuity or impedance irregularity.