Performance Evaluation of Hybrid-Electric Architectures for Agricultural Tractors

The European parliament points out that agriculture sector can play a primary role in the green transition, thus it is necessary to exploit new approaches technologies to decrease the environmental impact of agricultural machinery. One of the most interesting approaches is the development of hybrid-electric tractors. These vehicles combine the traditional diesel internal combustion engine with an electric powertrain. This paper reports the modelling and simulation, performed modifying a simulation software typically employed for on-road vehicles, of 70 kW 4-wheel-drive hybrid-electric an orchard tractor, in two different architectures: the parallel and the power-split. The simulated driving cycle is the EPA REP05. The evaluation and the comparison of the performance and the environmental impact, in terms of fuel consumption and CO2 emissions, between the conventional and the hybrid-electric architectures have been carried out. Moreover, two levels of hybridization have been tested to evaluate the possible downsizing of the internal combustion engine. The presented work points out that the parallel and the power-split hybrid-electric architectures reduce the fuel consumption of 10% and 21%, respectively. The CO2 emissions lowered of 9% and 22%, respectively. Compared to those of a traditional orchard tractor.