Generalized optimal trajectory control for closed loop control of series-parallel resonant converters

In this paper, the generalized optimal trajectory control (GOTC) for the series-parallel resonant converter (SPRC) is presented. It allows the nonlinear resonant circuit of the SPRC having an arbitrary starting state to reach a desired steady state in the shortest possible time. Based on GOTC, a traditional feedback controller with inner current and outer voltage state-feedback is designed for an SPRC based DC-DC converter. The GOTC based feedback controller allows higher feedback loop gains to be used compared with simple frequency control of the resonant circuit. This results in either better disturbance rejection for the converter or the possibility of reducing output filter sizing. Simulation results are used to verify the theoretical claims at this stage.