A bidirectional power converter for AC grid and DC bus

This paper presents the development of a bidirectional converter for AC grid and DC bus. The converter adopts a full-bridge structure and utilizes average current control and sine pulse width modulation techniques for power factor correction and inverter design. The system's control core is based on a control chip, combined with control technology. By sensing the input and output voltages, the pulse modulation period is calculated to enhance the compensation speed of the overall control loop. This enables the converter to exhibit high power factor and stable output voltage capabilities, while functioning as an inverter with enhanced system reliability in the reverse mode, achieving the objective of bidirectional electrical energy transmission. Finally, a maximum rated output of 1 kW experimental platform was constructed to emulate AC grid of 220 V and a DC bus of 400 V, thereby validating the theoretical analysis and design methods proposed in this paper. The experimental results showed that with an AC grid voltage of 220 V, the efficiency reached a maximum of 97.09%. In the reverse mode, the efficiency reached a maximum of 96.98%. Through the converter, energy was fed back to the AC grid, achieving the objective of bidirectional energy scheduling.