PWM Technique to Minimize Output Voltage Distortion for Mitigating Motor Overvoltage Caused by the Reflected Wave Phenomenon

This paper introduces a PWM technique to minimize output voltage distortion for mitigating motor overvoltage caused by the reflected wave phenomenon. When high dv/dt switches are used in motor drive systems with long transmission lines, impedance mismatch leads to voltage reflection, which causes overvoltage at the motor terminals. To suppress this overvoltage, various PWM-based techniques have been investigated. The reference voltage generated by conventional methods, such as the maximum minimum pulse technique (MMPT) and the pulse elimination technique (PET), is analyzed based on the operating region. These methods distort the voltage waveform and degrade the output current characteristics. Severe degradation in output current may lead to control instability. The proposed PWM technique minimizes output voltage distortion by generating an improved reference voltage through a hybrid approach that combines conventional methods guided by the output voltage error. Its effectiveness was verified through simulations and experiments, demonstrating significant improvements over conventional techniques.