Back-stepping Control of Off-Grid PV Inverter

Recently back-stepping controllers have gained significant academic interests due to robust and stable performance when controlling complex nonlinear and linear systems. It does not require explicit system linearization around particular operating point; thus, its performance does not deteriorate with movement of operating point as in traditional linear control techniques. Therefore, this paper investigates the use of back-stepping control in Photovoltaic (PV) generator that operates in an islanding mode. The main significant of the back-steeping control is that it allows selection of controllers' gains of linear and nonlinear system using basic time or frequency domain specifications such as the desired settling time, overshoots and closed loop bandwidth. The performance of the back-steeping control under investigation has been validated with the aid of MATLAB/SIMULINK model that resembles a PV generator, which includes a PV array with maximum point power tracker, dc-dc boost converter and single-phase inverter that feeds a passive load. Simulation results show satisfactory performance and robustness against external disturbances.