Efficiency comparison of different powertrain structures intended for a hybrid skidder by utilizing a novel cascade optimization algorithm

Abstract

Hybrid powertrain presents a viable solution for reducing fuel consumption through powertrain electrification while simultaneously being independent from the electric grid or a charging station. Due to the fact that articulated forestry tractors (skidders) belong to the class of forestry machinery which is intended for field use, this operating independence is of high importance. A simple backward-looking model of a series hybrid powertrain skidder is developed and presented in this paper. The model is then optimized over a number of previously-defined operating missions which include realistic track slopes and variable loads. The results are compared with the results of conventional and parallel hybrid powertrains proposed in previous works. Optimization results show that total fuel consumption obtainable with the proposed series configuration over the parallel one is slightly higher (the total efficiency of series structure is slightly lower) when compared to the parallel structure. Therefore parallel configuration can be considered as optimal soulution.

Keywords

• Series hybrid skidder
• Forestry tractor
• Cascade optimization
• Efficiency
• Fuel consumption