4 research outputs found
Variable fractional powerâleast mean square based control algorithm with optimized PI gains for the operation of dynamic voltage restorer
Abstract The operation of Dynamic Voltage Restorer has been studied for the mitigation of supply voltage disturbances like sag, swell, distortions, and unbalances. A Dynamic Voltage Restorer with three singleâphase Voltage Source Converters has been implemented for this purpose. Dynamic Voltage Restorer's compensation capability has been evaluated while introducing the aboveâsaid voltage related disturbances in the supply by different means. A control algorithm named Variable Fractional PowerâLeast Mean Square has been proposed for generating the load reference voltage for Dynamic Voltage Restorer. Variable Fractional PowerâLeast Mean Square extracts the fundamental active and reactive component out of nonâideal supply voltage and is thus, used in generating reference load voltage. This algorithm is more robust with respect to disturbance due to variable step size and is computationally less expensive. In addition, an optimizationâbased approach has been proposed to estimate the approximate values of PI control gains. For this reason, a populationâbased optimization method known as Sine Cosine Optimization has been used. The added feature of the optimization method is the reduction of computational time as compared to conventional PI controller tuning. A model of Dynamic Voltage Restorer using Variable Fractional PowerâLeast Mean Square control algorithm with Sine Cosine Optimization tuned PI gains has been built in MATLAB Simulink as well as a reduced scale experimental prototype and their results have been presented with discussion