Performance evaluation of tuned PI controller for power quality enhancement for linear and non linear loads

In this paper, a 3-leg voltage source inverter (VSI) based Distribution Static Compensator (DSTATCOM) is used for load compensation in 3-phase 3-wire distribution system. The control algorithm is based on Synchronous Reference Frame (SRF) algorithm. This algorithm is used for extracting the reference source currents for power factor correction, load balancing and harmonic reduction. Tuning of PI (Proportional Integral) controller is done using trial and error method and also by Zeigler- Nichols (Z-N) method. Simulations are performed for various load conditions such as a reactive linear load, an unbalanced load and non-linear load. Power factor correction mode (PFC) for DSTATCOM is tested in MATLAB environment using SIMULINK and SimPower system toolbox.