FPGA-Based Implementation of Backstepping Controller for Three-Phase Shunt Active Power Filter Interfacing Solar Photovoltaic System to Distribution Grid

Abstract

The design and implementation of a controller for a solar photovoltaic system interfacing to the grid with shunt active power filter functionality are discussed in this paper. An inner harmonic current compensation loop and an outer dc voltage control loop constituted the control system. The inner loop is realized using a self-tuning filter (STF) based on instantaneous power theory, and the outer loop is realized using backstepping algorithm. The control algorithm is simulated under dynamic system conditions namely change in solar irradiation and change in load, in Matlab/Simulink environment. To ensure the effectiveness of the controller in mitigating the harmonic currents and interfacing solar PV system with distribution grid for real power exchange, the control algorithm is tested under steady-state and dynamic conditions and validated with the simulation results. The control algorithm is then implemented using a single all on-chip FPGA. Hardware co-simulation is carried out with the control system implemented in FPGA, and shunt active filter power circuit simulated in Matlab/Simulink. The hardware co-simulation results obtained are matching with the Matlab simulation results under dynamic system conditions and the controller design using FPGA is validated. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.