Achievement of MPPT by finite time convergence sliding mode control for photovoltaic pumping system

Abstract

In this paper, a new finite time stability approach is proposed for controlling the Maximum Power Point Tracking (MPPT) process. This approach is based on variable structure sliding mode technique. While standard Sliding Mode Control (SMC) forces the system to converge to the reference value in infinite time, the proposed method, Finite Time Sliding Mode Control (FTSMC), ensures the convergence in a given finite time. As a result, FTSMC ensure a fast error tracking capability. For the validation of this strategy, a Photovoltaic (PV) water pumping system is considered and intended to maintain this system operating at Maximum Power Point (MPP). A DC/DC power converter is inserted between the Photovoltaic Generator (PVG) and DC motor by the duty cycle, which is considered to be the control variable. Some simulation results are given for comparison with standard SMC and Perturb and Observe (P&O) methods.