Development of an advanced transmission line fault location systems. I. Input transducer analysis and requirements

As part of the development of an advanced, more consistently accurate transmission line fault location system (AFLS), an evaluation of the performance and requirements for voltage and current input transducers was made. Measurements of current transformer and burdens were made, and computer models of the steady-state and transient responses were developed. Burdens from the electromechanical relaying and metering equipment in the secondary circuits were found to be large enough to cause transient distortion of the current waveforms for some fault causes, and would not meet the stringent requirements for an AFLS. A recommendation was made to place the AFLS in the primary relaying circuits, where electronic relays having low burdens are installed