Three-phase interleaved buck PFC circuit and control method thereof

The invention discloses a three-phase interleaved buck PFC circuit and a control method thereof. The three-phase interleaved buck PFC circuit adopts interleaved parallel circuits, a step-down inductorand a filter capacitor are arranged, PID control is carried out on the capacitor voltage outer loop and the inductor current inner loop through the main controller, feedforward control operation is carried out at the same time, PWM control signals are obtained to control the switch tube, the size of the capacitor and the inductor of the circuit is reduced, the single capacity requirement of the switch tube is small, power grid current harmonic waves are reduced, cost is reduced, and therefore the power factor of a power grid is improved. 本发明公开了一种三相交错并联降压型PFC电路及控制方法，一种三相交错并联降压型PFC电路使用交错并联电路，设置有降压电感和滤波电容，并通过主控制器对电容电压外环、电感电流内环进行PID控制，同时进行前馈控制运算，得出PWM控制信号控制开关管，使得电路的电容、电感的体积减小，开关管单体容量需求小，电网电流谐波减少，成本降低，以提高电网的功率因数。