A robust control method for a DC motor-based photovoltaic pumping

This paper deals with the robust control of DC motor based on photovoltaic pumping system. We will use in this work the tools of nonlinear control to increase the yield of a photovoltaic panel and therefore the amount of water pumped. Maximum point tracking an algorithm using Perturb and Observe method with array voltage and current is used to generate the voltage reference which should be the PV panel's operating voltage to get maximum available power. The system is represented into a Takagi-Sugeno (T-S) fuzzy model. Then, the concept of Robust Parallel Distributed Compensation (PDC) is applied to design the control law. The PV current is considered as an exogenous input, and included in an uncertain matrix whose influence on the regulation error is minimized. This means that overall stability analysis is carried out when disturbance is taken into consideration. Control gains are then obtained by solving some set of linear matrix inequalities (LMIs).