Adaptive speed estimation with fuzzy logic control for PV-grid interactive induction motor drive-based water pumping

This paper proposes a fuzzy logic control for model reference adaptive system (MRAS)-based speed adaptation technique of an induction motor drive (IMD) used for the bidirectional power flow between a photovoltaic (PV) array and a single-phase utility grid on the same DC link for water pumping. This system comprises of one current sensor and one voltage sensor for sensing grid quantities and one current sensor and one voltage sensor for sensing the DC link current and its voltage. The DC link current is used to estimate three-phase motor winding currents. Phase current is reconstructed from DC link current through a space vector modulation technique. The mechanical sensorless control of the proposed system is achieved by stator voltage and current-based speed adaptation. The direct torque control (DTC) is used for an IMD. The generalised integrator-based fundamental voltage generation algorithm is proposed for power flow control between the single-phase utility grid and DC link voltage feeding an induction motor-driven water pump. The developed prototype is tested in the laboratory and its suitability is judged through various results under different conditions of insolation variations.