Development and performance evaluation of a PTO-based power assist system to improve traction force for electric...

Electrification of agricultural machinery is crucial for meeting environmental regulations, with electric tractors being a prime example. However, insufficient power during high-load operations, such as plow tillage, limits the field applicability of conventional electric tractors. To address this, we propose and evaluate a Power Take-Off (PTO)-based power-assist system to supplement the traction power. Three powertrain configurations were modeled and compared: (i) a baseline dual-motor coupling powertrain (DMCP), (ii) a speed-coupling DMCP with power-assist system, and (iii) a mixed-coupling DMCP with power-assist system. The performance was evaluated under measured plow tillage conditions, focusing on traction force, travel speed, and energy consumption, with the latter assessed using an optimal control strategy derived via dynamic programming. Under a demanding 55 kW workload, only the assist-equipped configurations operated within the required power envelope. The speed-coupling configuration delivered the highest traction torque through torque amplification, despite a slightly reduced maximum speed. This configuration also lowered energy consumption by up to 2.40% compared to the baseline DMCP. These findings confirm the proposed PTO-based power-assist system is a practical solution for enhancing high-load operability and energy efficiency without major powertrain modifications. Future work will focus on hardware-in-the-loop validation of the proposed configuration.