摘要
三电平VIENNA整流器因三相输入不平衡会给输入电流带来谐波污染,输出电容中点电位也存在波动。针对这一问题提出了采用单周期控制的三相四线制整流器,并对其工作原理进行深入研究。分析了采用单周期控制单边沿调制方式对输入电流的不利影响,揭示了整流器输入电流谐波含量与滤波电感、开关频率成反比。在此基础上,提出了三角载波的双边沿调制方式,改进的单周期控制可以使电感电流在上升和下降阶段都得到调制,从而有效抑制单边沿调制带来的低频奇次谐波,改善了输入电流的质量。仿真实验的结果证明了该理论分析的正确性,验证了改进单周期控制的可行性。
On the issues of fluctuation in the neutral-point and harmonic pollution caused by unbalanced input voltage, this paper adopts three-phase four-wire VIENNA rectifier based on one cycle control and analyzes its working principle deeply. Input current characteristic which is controlled by traditional single-edge modulation is discussed. The relation among harmonics in the input current, switch frequency and input inductor is revealed. Based on the analyses, this paper proposes a bi-edge modulation with triangular-wave as carrier. The inductance current could be modulated both at leading-edge and trailing-edge. Consequently, the low-frequency odd harmonics of inductance current is reduced, and the quality of the input current is improved. The validity of the theoretical analysis and feasibility of the advanced one cycle control strategy are verified by simulation results.
出处
《电力系统保护与控制》
EI
CSCD
北大核心
2016年第18期88-95,共8页
Power System Protection and Control
