Evaluation of Power Quality Indicators in DC Microgrids using Intelligent Contactors

Abstract:
In recent years, growing interest in direct current (DC) microgrids led to increased research and standardization efforts. In this context, previous research suggests that power quality (PQ) will improve compared to alternating current (AC) microgrids. However, PQ indicators still lack consistent definitions. Within this study, different PQ indicators are compared experimentally. To evaluate and analyze PQ, a branch of an industrial DC microgrid is used. Measurements are taken using a contactor with integrated monitoring and measurement technology. The acquired data is analyzed locally with respect to periodic and non-periodic PQ indicators. Compared to an oscilloscope, the intelligent contactor reliably captured mean and RMS voltage values in all conditions. This underlines the advantages of using an intelligent contactor for monitoring in a DC microgrid.