Mathematical analysis of an electric car in the aspect of the application of renewable energy sources

Abstract

This paper presents a model of an electric car based on the BMW i3 whose low-voltage electrical system and traction battery were supported by a photovoltaic system installed on the body of the vehicle. The photovoltaic system was installed on the roof, side doors and bonnet. The 350 Wp (Watts peak) system was made of semiflex panels. The input parameters for the model were the measurements taken during the simulated annual operation of the vehicle as driving time, weather conditions and their switching times. During stationary tests, the power of individual electrical consumers was measured and its maximum was 1.1 kW. The model included data on the electricity consumption for driving a given distance. The amount of electricity generated by the photovoltaic system was related to a stationary system of 4 kWp. The degree of shading and curtailment of energy generated by the photovoltaic system was measured during testing on a vehicle driving in urban conditions. In the vehicle under analysis, an additional energy stream supplied the 12 V electrical consumers and recharged the battery. The traction battery used to drive the vehicle during such a power supply scenario may increase the vehicle range by about 16% on average.