A decoupling discrete-time control methodology applied to shunt active power filter

To achieve a preferable solution to three-phase current coupling in shunt active power filter(APF), a decoupling discrete-time current control methodology is presented based on the detection algorithms for instantaneous reactive power and harmonics. With integration of α-β transform plus two independent current controllers, the proposed methodology can effectively implement decoupling control of the three-phase currents within a three-wire system, which can thereby eliminate the impact from the neutral-point voltage, with unique advantages of digital realization and reduced computation power. Both theoretical deduction and simulations demonstrate the effectiveness and feasibility of the methodology.