摘要
基于载波移相(CPS)调制的H桥级联型(CHB)有源电力滤波器(APF)是中高压系统谐波治理的有效手段。分析并指出了级联型拓扑在输出谐波电流时存在的源性谐波能量不均问题。当输出的谐波电流频率与单元输出电压中某一开关谐波频率一致时,将产生功率耦合,导致单元直流电容电压发散。针对性地提出了一种载波频率优化方法:通过引入载波频率偏移量,实现了单元输出电压开关谐波与APF输出谐波电流的功率解耦;讨论了不同的载波偏移量对电容电压波动的影响,并给出了最优频率偏移量计算方法。对比了载波频率优化方法和传统载波轮换方法抑制源性谐波能量不均的效果,体现了载波频率优化方法的优越性。仿真和现场应用证明了所提方法能够有效地防止直流侧电压的发散并将波动抑制在最小值。
In medium-high voltage system, cascaded H-bridge （CHB）-based active power filter（APF） with carrier phase-shifted （CPS） modulation is an effective choice to suppress harmonics. We analyze a special source-type harmonic energy unbalance problem, which happens when the compensation current frequency is consistent with the cell＇s output voltage switching harmonic frequency, resulting in the divergence of DC capacitor voltages. To solve this problem, a car- rier frequency optimization method is proposed. By appropriately adjusting the cartier frequency, this method decouples the switching harmonic voltage with the output current, and minimizes the DC voltage ripple. Compared with the tradi- tional carrier rotation method, the proposed method is much superior in suppressing source-type harmonic energy unbalance problem. Simulation and the field applications verify that the proposed method can effectively avoid the diver- gence of DC voltages and suppress the ripple into the minimum value.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2017年第1期104-113,共10页
High Voltage Engineering
基金
国家自然科学基金(51277137)~~
