Abstract
Advanced voltage and var control equipment requires the maximum voltage deviation of 0.1% despite of highly distorted waveforms and the frequency variation. Digital signal processing can satisfy this requirement using fast sampling and very fast 32-bit floating point operations by a DSP (Digital Signal Processor).
This paper describes the design philosophy of the voltage measuring method using an adaptive filter with high-precision measurement. In addition, total voltage measuring deviation characteristics are described in terms of adaptive digital filter characteristics, peak value operating principle, influence of gain deviations of element filters and influence of sampling frequency for adaptive filter.
