Dynamic Control and Analysis of DC-Capacitor Voltage Fluctuations in Three-Phase Active Power Filters.

This paper proposes a new control method of three-phase active power filters for reducing the dc capacitor voltage fluctuations in transient load change. The proposed control method introduces a new \boldsymbolk-step compensator, which maintains the mean active power flowing into the dc capacitor at zero every \boldsymbol1/(k-1) ac line period. Therefore, the compensator can suppress the transient voltage fluctuations across the dc capacitor even when a quick load change occurs. This paper theoretically reveals the relationship between the step number \boldsymbolk and the reduction effect of the dc voltage fluctuations. The experimental setup introducing the proposed seven-step compensator exhibits a good suppression effect of the dc voltage fluctuations and makes it possible to reduce the required capacitance value of the dc capacitor by a factor of seven. [ABSTRACT FROM AUTHOR]