Effectiveness of DSTATCOM to Compensate the Load Current Harmonics in Distribution Networks under Various Operating Conditions

The Distribution Static Compensator (DSTATCOM) is a compensating device which is used to control the flow of reactive power in the distribution systems. This paper focuses on power quality improvement with DSTATCOM on feeders feeding linear loads, nonlinear loads and DTC induction motor drive. In this paper, effectiveness of DSTATCOM in distribution networks to compensate the load current harmonics under various operating and fault conditions is discussed and implemented. Comparison of THD analysis for different types of loads under normal and various faults conditions with or without DSTATCOM is also done in this paper. DSTATCOM is realized using IGBT based PWM-VSI inverter having a DC bus capacitor. A dqo transformation based PWM current controller is used to derive gating pulses for the IGBT switch. The models are developed and simulated in MATLAB using Simulink toolbox. It is observed that DSTATCOM is effective in compensating current, harmonics, reactive power and improving the power quality of the distribution system.