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This work presents an adaptive feed-forward current fed battery-supported solar water pumping system using a synchronous reluctance motor (SYRM). It incorporates the impact of cross saturation in real time with the position sensorless vector control technique of SYRM. Moreover, a continuous estimation of direct axis inductance (Ld) is incorporated to ensure saturation in SYRM. The burden of the DC link voltage PI controller is relieved by the feed-forward term of an adaptive battery current, which is calculated from the photovoltaic (PV) array power, estimated output power and the estimated motor efficiency. A DC-DC boost converter is used for maximum power point tracking (MPPT) of the solar photovoltaic array. A voltage source inverter is employed to control the SYRM-pump drive, and to charge/discharge the battery, a bidirectional DC-DC converter is used. The system provides a cost-effective solution for an uninterruptable and rated discharge of the water supply. The solar PV array behaves as a primary energy source, whereas battery is used as a backup source and is charged by PV array when pump operation is suspended or operating at a lower rating. The satisfactory performance of developed system is verified through experimental results taken on the developed laboratory prototype. [ABSTRACT FROM AUTHOR]

This article deals with an improved control for synchronous reluctance motor (SyRM)-based photovoltaic (PV) water pumping system, eliminating the speed controller of position sensorless field-oriented control (FOC) of SyRM. The solar water pump drive involves two stages of power conversion. The reference quadrature axis current of FOC is estimated from available PV array power that is being continuously tracked for maximum power point. This eliminates the requirement of an additional speed controller. This improves the transient behavior of overall control under dynamic conditions such as varying solar radiation. A pole is eliminated from overall characteristic equation of open-loop dc link voltage control transfer function. As a result, a single proportional integrator controller satisfactorily controls the whole pumping system. The system is much easier to tune, and by default, immune to aging and variation in pump's constant. This improves fidelity and reduces the overall cost of the system. Performance of this system is validated through a developed laboratory prototype of solar PV array-fed SyRM drive for water pumping. The overall system performance is examined under different environmental conditions. [ABSTRACT FROM AUTHOR]