Control of DSTATCOM using nonparametric variable step-size NLMS: An experimental study

•Development of Nonparametric Variable Step-Size NLMS (NPVSS-NLMS) control technique for distribution static compensator (DSTATCOM).•Development of laboratory prototype of DSTATCOM for verification of real time performance of the NPVSS-NLMS control technique for power quality problems at distribution system.•Several power quality problems such as harmonic distortion, excessive reactive power and load unbalancing are compensated using developed test setup.•Improved performance of developed NPVSS-NLMS control technique is demonstrated by comparing with existing control techniques. The development of distribution static compensator (DSTATCOM) using nonparametric variable step-size normalized least mean square (NPVSS-NLMS) based control technique is presented in this paper. Numerous features of DSTATCOM such as harmonic alleviation, reactive power compensation and load balancing are demonstrated using NPVSS-NLMS controller. The laboratory prototype of shunt compensator is developed using a dSPACE DS1104 R&D controller having TMS320F240 as a slave DSP. Both MATLAB/SIMULINK based simulations and experimental test results are presented for demonstrating the steady state as well as dynamic performance of DSTATCOM. The developed control technique is compared with variable step size LMS (VSS-LMS) and modern control techniques viz. sliding mode controller (SMC) and model predictive control (MPC) in terms of filter type, weight convergence, complexity, harmonic compensation and sampling time taken. The NPVSS-NLMS based control algorithm for shunt compensator is performing satisfactory in all the above mentioned terms over conventional VSS-LMS controller. The scheme is found to be effective in reducing the total harmonic distortion (THD) of supply current as per IEEE-519 standard.