Improvement of an Existing Method of Asynchronous Sampling for Determining RMS Value

Abstract

Measuring a value by definition seems to be the best solution for getting the most precise results. In this paper, it is shown that by changing the general definition of root mean square (RMS) and average value of a periodic signal, their measurement can be improved. When measuring RMS with asynchronous sampling, it was observed that results were scattered around two values, and it was found that the main cause for this was initial sampling time. Redefining the RMS value has been proposed in order to increase the efficiency of the asynchronous method. After comparing the results based on general and proposed definition for RMS value, it was observed that there was significantly less scattering of results and higher accuracy. The simulation proved that the application of the proposed definition of RMS gives more accurate and precise results than the general definition for analog to digital (AD) converters with both lower and higher resolution.