SRM driven solar irrigation pumping system utilizing modified dual output SEPIC converter

This paper presents a modified SEPIC (Single Ended Primary Inductance Converter) suitable for solar PV based irrigation water pumping system using SRM (Switched Reluctance Motor) drive. The modified converter has two inductors in the output section for dual output configuration. It has all the merits of the conventional SEPIC converter with balanced dual outputs feeding the DC link capacitors of the mid-point converter. Inherent voltage balancing feature, eliminates the need of extra control architecture to balance the voltages across the DC link capacitors, thereby reducing the cost and complexity of the system. An IC (incremental conductance) MPPT algorithm is used to make the photovoltaic array operate at MPP (maximum power point) without oscillations and to increase the efficiency of the system. A proper selection of step size in MPPT algorithm, helps in achieving the smooth starting of SRM drive. The performance of the system is validated both by simulation in MATLAB/Simulink and by experimental results on a developed prototype of 8/6 SRM. The response of the system obtained under dynamic conditions, shows its aptness towards water pumping application.