A Quasi Single Stage Isolated Buck-Boost Mode Multi-input Inverter

Aiming at shortcomings of single new energy power generation, such as unstable power supply, discontinuity and changing with climate conditions, a quasi-single-stage isolated Buck-Boost mode multi-input inverter and master-slave power management SPWM control strategy with smooth and seamless switching in different power supply modes are proposed. The circuit topology, characteristic of steady principle and power management strategy are fully investigated. The circuit topology is composed of a bidirectional isolated Buck-Boost DC converter with a multi-input selector switch in series, and a polarity inversion bridge. The master-slave power management strategy is consisted of n-1 input voltage control loops, n power distribution circuits and instantaneous output voltage control loop with independent power control, it can realize smooth and seamless switching in different power supply modes. Designed and implemented 500VA 80-110VDC/220V50HzAC prototype has excellent performances such as high conversion efficiency, high quality of output waveforms, strong load adaptability, smooth and seamless switching in different power supply modes, etc.