Multicycle Optimal Trajectory Control With ZVS for LCC Converters Under Wide Range Load Transition

Fast dynamic response is a critical attribute for LCC resonant converters. This article proposes a multicycle optimal trajectory control (OTC) for LCC resonant converters under wide range load transition. The steady-state trajectories and characteristic equations are established. Then, the multicycle control trajectories are designed to enable the resonant tank to reach the new steady state quickly. Meanwhile, zero-voltage-switching on for all switches are ensured during all OTC cycles. With real-time load detection, the target power can be quickly determined, and the required OTC cycles can be found in lookup tables. The effectiveness of the proposed control is verified on a 1-kW prototype.