Modelling and simulation of a PV-inverter-asychronous motor association in photovoltaic pumping systems

In this paper, we introduce a method of control and sizing of photovoltaic systems in stand alone PV pumping plants. This approach is based on the dynamic model of the PV-DC/DC inverter-asynchronous motor. The DC-DC converter ensures an impedance adaptation between the PV and the load and an optimal PV panel output power extraction. However, the DC/AC converter ensures a PWM control of the induction motor and a sinususoidal output signal. This methodology allows an optimal control and monitoring of continuous-continuous and continuous-alternative converters by calculating respectively the DC/DC cyclic ratio and the DC/AC frequency. Contrary to classic methods, this method, which is based on the parametric model of the PV system, leads to a best prediction of the the PV installation especially with load and climatic fluctuations