Vienna converter fed two stage grid connected photovoltaic pumping system

A topology of Vienna converter fed two stage solar water pumping system interfaced with three phase grid supply is proposed. The system uses a Vienna converter, a boost converter and a voltage source inverter to drive an induction motor (IM) coupled centrifugal pump. The proposed system helps in eliminating the loss of water discharge due to varying solar insolation in standalone solar water pumping systems. The IM is controlled using simple scalar control while the maximum power point tracking is achieved using the incremental conductance technique. The input power quality is improved by the constant frequency switching of the Vienna converter. Various modes of operation on the availability of active power sources are identified and the photovoltaic pumping system (PVP) is modelled and its performance is simulated in detail. The system indices at starting, steady state and with varying solar insolations are analyzed. The simulated results show the feasibility of the proposed system in grid connected locations.