Comparison of RMS Value Measurement Algorithms of Non-coherent Sampled Signals

ODAY, high resolution analog to digital converters (ADC) are often used for precision measurements of voltage and current. The measurement uncertainty of the RMS value of the analog sinusoidal signal depends on the quality of the ADC and on the algorithms used for RMS estimation. This paper will focus only on the algorithms for RMS estimation of the sinusoidal signal. The comparison of classical algorithms and windowing based algorithms has been described in [1, 2]. RMS value of the sinusoidal signals with more than 5 periods can be estimated with several windowing based algorithms with the uncertainty better then measurement uncertainty of present ADC systems. The goal of this paper is to present a new method for estimating RMS value of the sinusoidal signal with less than 5 periods and to compare it with other RMS estimation algorithms. Comparison is done by calculating RMS value of the simulated signal of an exactly known RMS value, by random signal phase to simulate non-coherent sampling and with similar sampling rates to common ADCs.