Evaluation of hybrid concepts of drivelines for forest machines

Purpose and goal:

The purpose of this project has been to study different hybrid concepts on a scientific basis to get an idea of what is possible and what could be a good solution for the forestry industry. The simulation results presented in this project show that hybrid solutions are worth considering as a solution to minimize fuel consumption of forest machines.

Expected results and effects:

The project presents a comparison in fuel consumption when using the hydrostatic transmission, the series hybrid and the parallel hybrid. Simulation results show a great potential to reduce fuel consumption of forest machines by 40% if hybrid solutions are considered.

The objectives of this project were successfully achieved, and the results provide guidelines for future work towards forest machine with significantly lower carbon footprint combined with the same high productivity. Approach and implementation:

The project was carried out through quasistatic simulations, where a driving profile for forest machines was created. The models have been developed and simulated in Matlab/Simulink. Three concepts have been evaluated and compared; hydrostatic transmission, series hybrid and parallel hybrid. During the evaluation, all elements have been kept the same for all simulations and models, i.e. the same internal combustion engine, the same electric motor and the same battery.