Power Measurement in EV Motor and Inverter Development

This technical article focuses on the measurement of power, efficiency, and loss in motor drive systems utilized in electric vehicles (xEVs). It outlines the challenges associated with the electrification of automobiles, particularly the need to enhance the efficiency of motor drive systems while minimizing their size. The article details the architecture of powertrains in battery electric vehicles (BEVs), emphasizing the role of inverters in converting battery output to drive motors. It discusses the necessity of precise power measurements to evaluate efficiency and loss, particularly in the context of new technologies such as wide-bandgap semiconductors. The article explains the measurement process, including the importance of simultaneous measurements and the use of power analyzers for accurate data collection. Additionally, it highlights the significance of stable zero-cross detection in measuring efficiency and loss accurately. The article concludes by addressing the complexities of measuring power in two-motor systems, which are gaining traction in xEV applications.