A three-phase active power filter based on park transformation

This essay deals with an improved active power filter based on the generalized instantaneous reactive power theory, of which the instruction current is calculated simply; which also will not be affected by voltage distortion and can be applied to unbalanced load current. The whole structure of electrical circuit is simple and has a good economy performance for this active power filter which only has three group switchers in three-phase four-wire system. This active power filter is prone to applied in industry for its low switching frequency and losses. Then proposing a control method can arbitrary regulate the power-factor of active power filter. Consequently, producing an active power filter possess the function of static via generators. The simulation results show it has a good dynamic and static performance, can compensates harmonic and reactive current of system effectively, increasing power-factor and transmission efficiency of power transmission lines.