Resonance Suppression of GaN-based Motor Drive System with Output Filter based on Virtual Damping Strategy

The adoption high-frequency power devices such as gallium nitride (GaN) in motor drive field can significantly reduce system volume, reduce losses, increase system power density, and reduce audible noise during motor drive system operation. But it also brings about the problem of excessive dv/dt and di/dt. In this paper, the LC filter is introduced into the servo drive system based on GaN power device. An active damping method based on virtual damping is proposed to solve the electrical resonance problem caused by the LC filter. Compared with the traditional hybrid damping method, the active damping method proposed in this paper reduces the power loss caused by damping network under the condition of similar adjustment time. Moreover, this method is suitable for LCL resonance suppression in motor drive system. Finally, the experiment results verify that the method can suppress the resonance caused by the output filter and realize the sine wave motor drive on an inverter with 100 kHz switching frequency.