Analysis and Control of Wireless Motor Drives With a Single Inverter in Primary Side

In motor drives supplied through wireless power transfer (WPT) systems, a high frequency inverter and a low frequency one are commonly used in the primary and secondary sides of the system, respectively. This arrangement causes reduced reliability and efficiency, and high cost. Besides, using an electrolyte isolator like big dc capacitor, shorten the system lifetime. This capacitor is usually located in parallel with the motor drive system. So, the capacitor fail leads to a total system failure. In this article, a multi-functional single inverter used in the primary side dispatch as the high-frequency ac power via a magnetic link as well as driving an induction motor without any extra inverter in the secondary side. This is obtained by using a simple AC chopper in the secondary side as a wave shaping convertor. In this way, the desirable ac power can efficiently be injected into the motor whereas the WPT system efficiency is improved by up to 5%. The modeling and mathematical analysis of the proposed wireless drive are presented. Also, the performance of the drive under an open-loop V/F control system is verified by simulation and experimental results. AC/AC converters, electric vehicles, wireless motor drives, wireless power transfer.