Dual-Loop PR Control for Collapsed H-Bridge Single-Phase 400Hz Power Supply

Due to the requirement of total harmonic distortion and the time delay of the digital controller in a single-phase 400 Hz power supply, the traditional proportional integral differential controller cannot track sinusoidal waveforms with zero static error. To improve the performance, proportional-resonant control has been analyzed and contrasted in this paper. On this basis, a Dual-Loop Proportional-Resonant control is proposed, which is implemented with the high switching frequency to provide sufficient control bandwidth to reduce the 3rd, 5th and 7th order harmonic. Finally, experiments on a single-phase 400 Hz power supply prototype show satisfactory results of the Dual-Loop Proportional-Resonant control feeding linear/nonlinear and disturbance loads.