A Novel Algorithm for Four Phase (Multi-phase) Source Side Load Balancing and Power Factor Correction

Due to the potential benefits resulting from the use of more than the conventional three phases in transmission, some interest has also grown in the area of multi-phase (phase order more than three) machines in recent years. Multi-phase loads particularly in the form of inverter fed induction motor drives suited to high power and specialized applications, are receiving growing attention in the literature. This multi-phase source for such drive application may be derived from transformer connection (3phase to 4-phase) or by DC link 4-phase inverters. These sources will face the problem of unbalance, harmonic distortion and poor power factor operation. In view of these developments, this paper deals with the supply side load balancing and power factor correction in such load circuits. The proposed compensation scheme uses the shunt current source compensation whose instantaneous values are determined by the instantaneous symmetrical component theory. An ideal compensator in place of physical realization of the compensator has been proposed in form of a current controlled voltage source inverter. The compensation schemes developed in the paper are tested for their validity on 4-phase (4-wire & 5-wire) circuits through extensive simulations for unbalanced loading and phase outages. The simulation results of the compensation theory and the ideal compensator verify the proposed compensation method.