Self-regulated DC-link control of synchronous reluctance motor-driven solar water pumping system

摘要

This study deals with a two-stage photovoltaic (PV) array-fed irrigation pump using a synchronous reluctance (SynREL) motor drive. In this scheme, a boost converter is utilised for harvesting maximum available power from a PV array through an incremental conductance-based maximum power point tracking algorithm. Here, it feeds power to a voltage source inverter through a DC-link capacitor. The prime objective of the proposed system is to provide water supply for domestic and irrigation purposes; therefore, to avoid complexity and for increased reliability, the speed/position sensor is eliminated. A speed/position observer is utilised for the estimation of angular position of SynREL motor. A PV feed-forward term is used to estimate the reference speed, which aids in enhancing the transient behaviour of proposed system. Moreover, the control is inherently resistant to the ageing-related variation in pump's constant. The applicability of proposed water pumping system is verified through test results, recorded on a developed prototype in the laboratory under varying atmospheric conditions.