Harmonic Interaction Effects on Power Quality and Electrical Energy Measurement System

This paper presents an investigation of the harmonic interaction effects on power quality (PQ) and electrical energy measurement and billing system. In this study two nonlinear loads, a programmable AC source and two power meters are used. An oscilloscope also was used to record the voltage and current signal. The results show that the total harmonic current distortion (THDi) level is a function of the harmonic interaction between each harmonic order of each load. The electrical quantities are influenced as well. Therefore, the characteristics of each load will influence the results. Furthermore, the analysis through Conservative Power Theory (CPT) confirms that the low power factor (PF) of the loads is mainly due to the nonlinearity, and not the reactive power. This is an important question because the PF affects the electrical energy measurements and, consequently, the electrical energy billing. Other contribution of this paper is to show the harmonic interaction effects on electrical energy measurement and billing systems quantitatively.