在单相高频整流器中抑制直流纹波电流的控制方法研究

Research on Control Strategy of Mitigating the DC Ripple Current in Single-phase High Frequency Rectifier

在直流侧无电解电容的情况下,单相整流系统二倍交流频率脉动的输入瞬时功率会在输出直流端产生二倍频的纹波电流,危害直流侧的设备。在单相高频整流器中分裂交流滤波元件构成单相差分输入高频整流电路,本文针对此电路拓扑,通过对比控制电压、控制电流2种模式下的波形控制方法,分析2种模式下控制方法的优缺点,提出了一种最优的控制电压模式波形控制方法,该方法不仅能实现单位功率因数、抑制直流电流纹波,而且具有有效降低变换器内部的循环流动能量、不引入其他谐波等优点。本文对波形控制方法进行了详细的理论分析,并通过仿真验证了所提出控制策略的有效性。该方法可以推广至无电解电容电力变换相关的应用。

The conversion of AC power into DC power through a single phase rectifier will typically intro- duces a low-frequency current ripple（at twice the AC input voltage frequency）at the DC input side of the rectifier system. Without a large capacitor at the DC-link,this non-negligible low-frequency current rip- ple will be detrimental to its output utilities. The AC filter component is divided and reconstructs as the single phase differential high-frequency rectifier circuit. Based on this topology, the comparisons of two waveform control algorithms of voltage control mode and current control mode are presented to analyze their advantages and disadvantages. An optimized waveform control method of voltage control mode is proposed in this paper. There are some advantages： unity power factor,without the low-frequency current ripple, a low circulation energy inside the rectifier and without other undesired harmonics. Theoretical analysis and simulation results are provided to verify the effectiveness of the proposed wave-form control algorithm. This algorithm would be appropriate to the power conversion applications Without electrolytic capacitor.