Mathematical modelling and performance evaluation of a stand-alone polycrystalline PV plant with MPPT facility

Photovoltaic (PV) generation has now-a-days proved to be a cost-effective method for renewable power generation with minimum environmental impact. Due to environmental and economic benefits, PV is now being widely deployed as a distributed energy resources (DER) in distributed generation systems or microgrids. Extensive laboratory-based research and simulation studies are being performed for assessing its effectiveness as DER in microgrids. Simulation studies mostly involve development of mathematical models which can account for the variation of PV output with solar irradiance and ambient temperature as well as the simulation of MPPT feature that is built in the inverters usually interfaced with the PV arrays. Simulation studies of microgrids with interconnected DERs and elaborate control schemes often warrants the development of simple and robust mathematical models for PV arrays that would pose low mathematical burden on the system, have low data storage requirements and which can be represented by standard block sets of a modelling software. At the same time, the models should be able to simulate the weather dependent electrical behaviour of the PV modules. This paper reports on the development of a DC voltage source model of a polycrystalline PV Array in MATLAB Simulink and its performance analysis under various loading and weather conditions as well as the application of the model to develop a load shedding scheme for a stand-alone PV system.