PV Array Fed Synchronous Reluctance Motor Driven Water Pumping System with Grid Integration and Seamless Operability

This article deals with control of a single-phase grid-connected solar photovoltaic (SPV) array based synchronous reluctance motor (SynRM) driven water pumping system with seamless mode transition and power quality improvement capability. Presented system provides an uninterruptable power supply to dedicated water pump and domestic loads even under grid absence by transferring control to standalone mode. As a result, smooth transition from grid-connected operation (GCO) to standalone operation (SAO) and vice versa provides higher system reliability. A second-order generalized integrator with frequency lock loop (SOGI-FLL) based control algorithm with SPV feedforward term is utilized for voltage source converter (VSC) in GC operation. Net active component of load current is extracted by SOGI-FLL current control. To make system cost-effective, a position sensorless vector control algorithm is implemented in real-time incorporating impact of saturation in motor. Multiple second-order generalized integrator (Multiple-SOGI) is utilized to estimate stator flux, from which rotor position and speed information are derived. It performs better than conventional sensorless algorithm showing improvement in cost and computational burden. This system provides a reliable solution for an uninterruptable and rated water discharge. Efficiency of introduced control strategy for a water pumping system synchronized with a single-phase photovoltaic grid is showcased through test outcomes obtained from a laboratory-based prototype.