Instantaneous space trajectories of a vector controlled active filter

This paper discusses the transient behavior of a strictly current vector controlled three-phase power active filter, which does not require hysteresis current controllers. Its transient performance is analyzed in terms of its voltage, current and current error instantaneous space trajectories. The vector control strategy determines precisely the region to which a previously defined instantaneous space vector current error belongs. Afterwards, the required inverter output voltage vector that makes this current deviation equal to zero is also determined by the vector controller. Under the knowledge of these vector regions, a set of inverter switching commutation tables are created to produce the best switching action. The vector nature of this control, is analyzed with reference to a selected number of instantaneous space trajectories and time oscillograms of its main vector variables, which are included in the paper.