This paper proposes an LCL-filter design based on the modulation index for grid-connected hybrid active neutral point clamped (ANPC) inverters. The three-level hybrid ANPC inverter consists of silicon insulated gate bipolar transistors and silicon carbide metal oxide semiconductor field effect transistors to reduce the switching losses. LCL-filter parameters for the three-level hybrid ANPC inverter are calculated using the current ripple factor. The current ripple factor is affected by phase voltage, which varies according to the modulation index, and therefore the inductance on the inverter side must be considered with the modulation index. To design inductance on the inverter side, the output phase voltage and grid voltage are used to analyze the current ripple factor. The filter capacitor and the inductance on the grid side are designed based on the reactive power absorption and current ripple attenuation. The effectiveness of the proposed LCL-filter design method is validated via simulation and experimental results.

本文提出了一种基于调制指数的LCL滤波器设计，用于并网混合有源中性点钳位（ANPC）逆变器。三级混合式ANPC逆变器由硅绝缘栅双极型晶体管和碳化硅金属氧化物半导体场效应晶体管组成，以减少开关损耗。使用电流纹波因子计算三电平混合式ANPC逆变器的LCL滤波器参数。电流纹波因数受相电压的影响，相电压随调制指数而变化，因此，必须将逆变器侧的电感与调制指数一起考虑。为了在逆变器侧设计电感，使用输出相电压和电网电压来分析电流纹波系数。基于无功功率吸收和电流纹波衰减来设计电网侧的滤波电容器和电感。通过仿真和实验结果验证了所提出的LCL滤波器设计方法的有效性。