PSO-Enhanced Optimization of Sliding Mode Controller and Observer for a Photovoltaic Pumping System

This work presents a non-singular fast terminal sliding mode controller based on a third-order sliding mode observer for a Photovoltaic Pumping System (PVPS). The system comprises a photovoltaic generator (PVG) coupled to a cen-trifugal pump through a DC-DC boost converter and a direct current (DC) motor. The duty cycle of the boost converter is regulated using a non-singular fast terminal sliding mode control (NFTSMC) technique. The third order sliding mode observer (TOSMO) is employed for two main objectives. Firstly, it relies exclusively on the solar array voltage sensor, resulting in cost re-duction for PVPS. Moreover, it contributes to resolving concerns associated with the high-gain observer (HGO), known for its sensitivity to uncertainties and disturbances. The Particle Swarm Optimization algorithm (PSO) is exploited to optimize the gains of both the developed controller and observer. To demonstrate the effectiveness of the designed approach, a comparative study between the proposed control scheme and a sliding mode controller based on the High Gain Observer (SMC-HGO) is conducted under variable atmospheric conditions using simulation in the Matlab/Simulink platform. The simulation results demonstrate that the proposed approach ensures fast tracking response, higher precision, and robustness against variable climatic conditions and uncertainties.