Efficient controller of DSTATCOM based on combination of Adaline and SOGI-FLL for power quality improvement

This work proposed a new control algorithm based on a combination of Second order generalized integrator-frequency locked loop (SOGI-FLL) and Adaptive linear neuron (Adaline) based least mean square (LMS) for the three-phase four-leg Distribution static compensator (DSTATCOM). SOGI-FLL play a vital role for grid synchronization, and Adaline LMS based filter used for extraction of the reference current. Adaline (LMS) controller is a fast adaptive filter. This work consists of two segments; First, synchronization of the frequency and phase of the power inverter with the grid through the SOGI-FLL and second, the extraction of reference current for controlling the inverter through the Adaline LMS. Mathematical modeling of both controllers is also elaborated in this work. For the purpose of DC and AC voltage control, Genetic algorithm-based approach has been selected with tuning of proportional integral controller gains. The grid consists of three phase supply with different loads such as static load, dynamic load, unbalanced linear and non-linear load. The DSTATCOM has been fixed at the point of common coupling of the grid to resolve different power quality concerns such as excess harmonics, prominent reactive power, phase unbalanced, deterioration of power factor etc. The complete DSTATCOM system along with the grid has been modeled and executed in MATLAB/Simulink background.