Performance analysis of MPPT techniques in a PV-powered water pumping system using an induction motor

Recent advancements in photovoltaic water pumping systems (PVWPS) have garnered significant attention from researchers, driven by their reliance on clean solar energy and their potential for sustainable water management. A typical PVWPS configuration includes a three-phase asynchronous motor (ASM) coupled to a centrifugal pump and powered by a photovoltaic (PV) generator. To optimize power extraction from the PV source, a maximum power point tracking (MPPT) algorithm is employed in conjunction with a boost converter. The system integrates two main control strategies: an MPPT controller for the three-phase inverter and a Field-Oriented Control (FOC) scheme for the asynchronous motor. This study introduces an enhanced perturbation and observation (P&O) MPPT algorithm featuring adaptive step-size control. The proposed method effectively reduces steady-state oscillations and improves the efficiency of power extraction in PV systems. The second control unit, based on FOC, regulates the induction motor by generating the switching signals for the voltage source inverter (VSI). Together, these control units play a vital role in system operation, contributing to improved efficiency and overall performance. The key innovation of this work lies in the integration of the improved P&O MPPT method. Extensive simulation analyses conducted under various irradiation conditions demonstrate that the enhanced algorithm achieves superior tracking performance compared to conventional P&O methods. Furthermore, the effectiveness of the FOC strategy implemented with a two-level inverter has been experimentally validated. The control approach was executed using a dSPACE DS1104 digital signal processor board in an ASM drive system.