有源滤波器的直流侧通常配置很大的电解电容，电解电容器的电压纹波额定值较低，损耗较大，应对电容值作出合理选择以避免内部发热。面对大容量的谐波补偿要求，有源滤波器(Shunt Active Power Filter,SAPF)需要进一步降低系统体积和成本。针对电容值与直流电压纹波关系这一问题，分析了三相SAPF补偿系统的瞬时功率流动，得到对直流电压波动有影响的功率分量，并在特定的负载条件下求取了振荡功率的积分值，得到电容能量波动的精确值，提出了一种考虑电容纹波电压关系的电容容量优化设计方法。利用Matlab仿真模型并与其他文献比较，验证了本文所提思路及结果的正确有效性。
英文摘要:
The DC side of the active power filter is usually equipped with a large electrolytic capacitor, which has low voltage ripple rating and large loss. A reasonable selection of the capacitor value should be made to avoid internal heating. In view of the problem of the relationship between the capacitance value and the DC voltage ripple, the instantaneous power flow of the three-phase SAPF compensation system is analyzed to obtain the power component that affects the DC voltage fluctuation, and the integration of the instantaneous active power AC components is obtained under a specific load condition, then the accurate value of the energy fluctuation of the capacitor is obtained. An optimization design method of capacitance considering the relationship of capacitance ripple voltage is proposed. The validity and effectiveness of the conclusion were verified through the simulation model and the comparison with the results by other relative article.