Improved Control Schemes for Input Current Fluctuation Reduction and Output Voltage Line Regulation in Two-Stage Pulsed Load Power Supply

A novel control scheme for input current fluctuation reduction and output voltage fast line regulation in the two-stage pulsed load power supply (PLPS) is proposed in this paper. The PLPS comprises the front-end and back-end stages, where the front-end stage is a phase-shifted full-bridge (PSFB) converter and the back-end stage is a buck converter. Since the moving average filter (MAF) presents a low magnitude at the moving window frequency and its multiples, introducing the MAF in the voltage loop can suppress the input current ripple without sacrificing the dynamic performance. Moreover, based on the small-signal modeling, it is found that the storage capacitor voltage fluctuation seriously impacts the output voltage line regulation. The proposed storage capacitor voltage feedforward (SCVF) control scheme can accelerate the output voltage line regulation and fast dynamic response. Finally, simulations are implemented to validate the proposed control scheme, and the results show the effectiveness.