Abstract
Today, most research on electric vehicles is focussed on urban or metropolitan area traffic. However, a considerable number of people in Europe live in mixed urban-regional areas. In these areas, the demand for full electric vehicles is growing rapidly. Therefore, Heilbronn University has launched a research project to identify the specific needs of individual and commuter traffic for electric car operation in urban-regional areas. Furthermore, strategies for moderate electrical energy consumption and range extending are to be identified.
Since August 2010, a plug-in battery-powered automobile has been available as a research car at the Automotive Systems Engineering research department. This car is a 4-seated modified conventional internal combustion engine vehicle now powered by 26 lithium-based batteries, each with a capacity of 160 Ah and a voltage of 3,2 V. The car has been supplemented with additional equipment for the measurement and storage of state variables like motor current, regenerative braking current or vehicle speed, for example driven by an electric motor with a permanent power of 15 and a peak power of 26 kW, a maximum speed of 120 km/h and an operation range up to 130 km is possible.
The paper and the presentation reports first results of the electric car operation focussed on commuter traffic. Here, different commuter traffic profiles are determined ranging from a commuting distance of 5 up to 50 km including urban, highway and regional traffic conditions. By parallel GPS position location and recording, any elevation influence on energy consumption is recorded. Also, the climate influence on energy consumption is analyzed. An additional hilly traffic profile takes a slightly montainous landscape into account. For all investigations, the energy regeneration balance by braking is analyzed, evaluated and discussed.
Keywords: Electric car, commuter traffic, regenerative braking, driving cycles, range extension