Stochastic-gradient-based control algorithms for power quality enhancement in solar photovoltaic interfaced three-phase distribution system

Abstract

Here, stochastic-gradient-based adaptive control algorithms have been discussed and employed for power quality enhancement in a Photovoltaics (PV) integrated distribution system. Least mean square (LMS), least mean fourth (LMF), sign-error LMS, and $\epsilon$-normalised LMS ($\epsilon$-NLMS) have been implemented as control algorithms for the estimation of fundamental load current. The performances of these adaptive algorithms are compared under steady-state and dynamic conditions under the non-linear load conditions in a closed-loop three-phase system. The main aim of implementing these algorithms is reactive power compensation, power quality enhancement, and load balancing in a single-stage three-phase grid-tied PV system. The hysteresis current control (HCC) technique is used to generate switching pulses for the three-phase Distribution Static Power Compensator (DSTATCOM). An MPPT is also employed to ensure maximum power delivery from the solar PV array. PV integrated three-phase single-stage distribution system with adaptive control algorithms is implemented in MATLAB/Simulink environment as well as in experimental environment to achieve the goals per standard IEEE-519.