Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title Method for Improving Overmodulation Performance of an Inverter for the Enhanced Output Torque of AC Motors
Authors Hye-In Jeong ; Sang-Hoon Kim
DOI 10.6113/TKPE/2019.24.4.273
Page pp.273-278
ISSN 1229-2214
Keywords AC motor; Inverter; Output torque enhancement; Overmodulation performance improvement; Voltage gain compensation
Abstract This study proposes a method for improving the overmodulation performance of a three-phase inverter to obtain an enhanced output torque for the AC motors. In the inverter-fed AC motor drives, the output torque of the motor can be enhanced by utilizing the overmodulation region as well as the linear modulation regions of the inverter. The overmodulation method is used for this overmodulation operation of the inverter. However, the voltage gain, the ratio of the output voltage of the inverter to the reference voltage achieved by the conventional overmodulation methods becomes nonlinearly smaller than unity. Therefore, the effect of improving the output torque of the AC motors is insignificant even when the overmodulation region is utilized. In this study, we propose a method that improves the overmodulation performance of the inverter by compensating the limited amount of the reference voltage in the overmodulation operation to enhance the output torque of the AC motors. The effectiveness of the proposed method is verified through the simulations and experiments with an 800 W permanent magnet synchronous motor.