Abstract
Power system control and protection equipment has required higher sensitivity and operational reliability than conventional one.
Studies of digital signal processing suitable for electric power systems fulfill this objective using fast sampling and digital filtering by a 32-bit floating point DSP (Digital Signal Processor). The sampling rate of 3kHz is carefully selected in order to separate the power spectrums of the A-D conversion output errors from the signal bandwidth. The new 12-bit A-D conversion unit equipped with a recursive-type digital filter achieved the equivalent high resolution of 14-bit conversion.
This paper describes the design concept and the characteristics showing applications to current differential relays, distance relays and power system controllers.