Control Scheme for DSTATCOM Based on Frequency-Adaptive Disturbance Observer

Harmonic-related power quality problems can be solved using a distribution static compensator (DSTATCOM) system, but its performance is very prone to frequency nonadaptiveness and harmonic disturbance presence in the control scheme. In this paper, a new control scheme based on frequency-adaptive disturbance observer is presented to improve power quality at the distribution supply. The proposed disturbance observer is utilized to remove the harmonics from the nonlinear load, thereby enhancing the magnitude estimation accuracy of the fundamental load current. The performance of the proposed control scheme has been assessed with a prototype model. The simulation as well as experimental results shows that the operation of DSTATCOM system is satisfactory for power quality improvement.