Control strategies for load compensation using instantaneous symmetrical component theory under different supply voltages

In this paper, the theory of instantaneous symmetrical components is applied to explore various control strategies of load compensation, under different supply voltages. When the supply voltages are balanced and sinusoidal, all these strategies converge to the same compensation characteristics. However, when the supply voltages are not balanced sinusoids, these control strategies result in different degrees of compensation in harmonics, power factor and neutral current and also compensator ratings. These strategies are discussed in detail and a comparative study of their performance is presented. The performance of the strategies is compared in terms of the rms, total harmonic distortions, power factor of source currents and filter ratings. A three-phase four wire distribution system with unbalanced and nonlinear load is considered for simulation study. The detailed simulation results using MATLAB are presented to support the proposed the compensation strategies.