Control of high frequency resonant inverter system, design and implementation

Resonant inverters are connected to high frequency AC (HFAC) bus, through which power is delivered to different locations for points-of-use power management. Such a system is subject to more perturbations and load uncertainty than inverter with a single load, while the fast response of the resonant inverter is mandatory. A high frequency full-bridge resonant inverter with series-parallel resonant tank is proposed with a novel voltage control method. A one-cycle controlled (OCC) phase shift modulation (PSM) is proposed to effectively compensate the input line variations and load perturbations. The uncertainty model of the high frequency resonant inverter is analyzed for resonant tank component tolerance, input line and load variations. A voltage feedback controller is designed based on the robust control theory, and implemented with analog discrete devices. The proposed control scheme has the advantages of fast response to the input line and load perturbations. The approach of control design guarantees the robust stability and performance of the system. The system performance is verified with both simulations and experimental results in a prototype resonant inverter of 150W, 1MHz and output voltage 28V.