Hybrid compensation for harmonic, reactive power and unbalance under dq0 coordinates

This paper presents a hybrid compensator for harmonic, reactive power and unbalance under dq0 coordinates. This compensator is applicable to un-balanced three-phase three-wire or three-phase four-wire system. A novel calculating method is developed to obtain harmonic, reactive power and unbalanced components under dq0 co-ordinates. A practical hybrid compensator on the basis of theory introduced above is designed as well, in which the passive part, thyristor switched capacitor (TSC), is used to compensate reactive power and the active part, active power filter (APF), is used to suppress harmonic, negative-sequence and zero-sequence components in load currents. Simulations are performed and the results are presented.