This study presents a reduced switch three-phase three-level H-Bridge-based shunt active power filter (SAPF) for the mitigation of current harmonics, the reduction of current unbalance and the injection of reactive power. This recommended SAPF is developed by using two H-bridge and two DC-link capacitors. Compared to the conventional three-level H Bridge-based SAPF, the eight-switch cascaded H bridge (ES-CHB)-based topology saves four semiconductor switches and one DC-link capacitor. The ES-CHB-based SAPF saves the power electronic components and reduces voltage stress across each switch by introducing a small AC capacitor in series with coupling inductor in each phase. This LC circuit also reduces the harmonic stress of SAPF by tuning at the sixth order of current harmonics. The only drawback of the suggested SAPF is the DC link voltage unbalances. To address this problem, a modified feedback control strategy is proposed in this study. The modified controller regulates the DC link voltage at the desired voltage and mitigates the DC link voltage unbalances, by using reactive power flow control and active power flow control, respectively. The performance of the suggested eight-switch three-level CHB-based SAPF is evaluated through MATLAB simulation and experimentally verified through the hardware implementation.

中文翻译：

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基于八开关CHB的三相三相并联有源电力滤波器

这项研究提出了一种减少开关的三相三电平基于H桥的并联有功功率滤波器（SAPF），用于减轻电流谐波，减少电流不平衡和注入无功功率。通过使用两个H桥和两个DC链路电容器来开发此推荐的SAPF。与传统的基于三级H桥的SAPF相比，基于八开关级联H桥（ES-CHB）的拓扑节省了四个半导体开关和一个直流链路电容器。基于ES-CHB的SAPF通过在每个相中引入一个与耦合电感器串联的小型AC电容器，节省了功率电子组件并降低了每个开关两端的电压应力。该LC电路还通过以六阶电流谐波进行调谐来降低SAPF的谐波应力。建议的SAPF的唯一缺点是直流母线电压不平衡。为了解决这个问题，本研究提出了一种改进的反馈控制策略。修改后的控制器分别通过使用无功功率流量控制和有功功率流量控制将直流链路电压调节到所需电压，并减轻直流链路电压的不平衡。通过MATLAB仿真评估了建议的基于八开关三级基于CHB的SAPF的性能，并通过硬件实现进行了实验验证。