A State-Observer Based Position Estimation Scheme Employed for the Control of a SRM Drive for Grid-Tied Solar Water Pumping System

This paper presents an observer based rotor position estimation of switched reluctance motor employed for solar grid-interfaced water pump. The elimination of mechanical position sensor reduces the complexity in control, improves the reliability, eliminates the corresponding real-time circuitry and their use is unadvisable in case of submersible applications. besides these, elimination of mechanical position sensor reduces the overall cost of the drive, as it occupies a major portion of cost in case of medium power drives. In this paper, a state-observer is implemented for the estimation of SRM position and speed for the control of the drive. In this work, the developed water pump drive is integrated with a three-phase distribution grid to support the application. A three-phase voltage source converter (VSC) is used to integrate utility grid with the pump drive and to maintain the power quality parameters. The measures are taken to maintain all the power quality parameters and also the load unbalance condition is also addressed. The overall system is simulated in MATLAB/Simulink to record the various system parameters along with its steady state and transient response. The overall response of the drive system is found to be suitable for the application and also the grid parameters noted are within the safe limits of operation set by the IEEE Standards.