A High Voltage Gain Resonance Converter and its Voltage Balance Control

With the promotion of new clean energy, the solar panels with low output voltage are intended to connect to the high voltage level DC bus. The converter with pulse width modulation (PWM) controlled active boost quadrupler rectifier (ABQR) owns high voltage gain and cased H-bridge three-level (TL) circuit is very suitable to this application. Without flying capacitors or clamping diodes, the phenomenon of voltage-unbalanced is easy to generate on the divided output capacitors of TL circuit. Many studies have been conducted but all of them aim to address the voltage unbalance caused by the time delay. In addition, the overshoot of the current enlarges the possibility of voltage-unbalanced but no paper has studied before. The new control scheme and the hardware improvement have proposed in this paper. Based on above two implementations, the voltage difference of the divided capacitors is under acceptable range in steady and dynamic procedure. Simulation and experimental results have verified the correct of the two implementations.