不控整流交错并联斩波变换器的电压前馈控制

Voltage Feedforward Control for Uncontrolled Rectified Interleaving Parallel Chopper Converter

针对大功率直流600 V供电,提出单相不控整流+四相交错并联斩波拓扑。为抑制不控整流产生的脉动直流电压对输出电压平稳的影响,首先建立了斩波变换器的等效电路,并推导出输入到输出的传递函数。其次依据前馈控制理论,将中间直流电压脉动分解成前馈通道和扰动通道,增加前馈通道来抵消扰动通道,进而给出了变换器的前馈调节规律。前馈只需在软件中实时计算前馈占空比,容易实现。仿真验证了算法的有效性。最后开发了一套400 kW样机,实物实验表明:中间直流电压以周期10 ms,幅值1 050～1 250 V波动时,前馈控制能有效抑制波动,将输出电压600 V波动控制在±5 V以内。

For high power direct current 600 V power supply,a single-phase uncontrolled rectifier＋four-phase interleaving parallel chopper topology is proposed.In order to suppress the disturbance effect on the output voltage of the uncontrolled rectifier pulsating voltage, first of all, the equivalent circuit of the chopper converter is established and the transfer function from input to the output is deduced.Then, according to the theory of feedforward control, the intermediate voltage is decomposed into the feedforward channel and the disturbance channel, and the feedforward channel is added to offset the disturbance channel and the feedforward regulation rule of the converter is given.Feedforward only need to calculate the feedforward duty cycle real time in the software,it is easy to implement.Simulation proves the validity of the algorithm.Finally, a set of 400 kW prototype is developed.The physical experiments shows that the feed-forward can suppress fluctuation effectively when the period of intermediate voltage is 10 ms and the amplitude is 1 050-1 250 V and the fluctuation of output 600 V is controlled within ±5 V.