A low ripple series-parallel resonant converter based on robust H∞ control approach

This paper presents a novel H_∞ robust controller for a series-parallel resonant converter. The proposed approach employs an accurate MIMO model of the converter to design the robust controller. The controller introduces a new feedback circuit which exhibits very tight output voltage regulation. The system is also robust against the variations of resonant tank components as well as load variations. Experimental results are presented for a 1.5 KW prototype system operating at 100 KHz to validate the feasibility of the proposed scheme. The experimental results demonstrate that 0.02% voltage regulation is achieved using the proposed controller which shows significant improvement in the output voltage regulation.