Accuracy limit of high precision stochastic watt-hour meter

Abstract

Stochastic watt hour meters are applied with several differences: stochastic digital signal is derived from a two-bit A/D converter; the A/D converter is a two-bit flash converter with uniform dither; and the logic circuits are supplied with only one voltage. It was connected in distribution net in parallel with standard induction three phase watt-hour meter which accuracy class was 0.2. The maximum daily difference was 0.07%, typical daily difference was 0.03% and total difference was 0.01%. The instrument has advantages of simple hardware and easy implementation of parallel measurement. The idea is very convenient for application in multichannel real-time RMS, power and energy measurements.