Abstract:Aiming at the problems of insufficient adaptability to ridge-planting parameters and limited endurance in existing electric agricultural machinery, a dual-power crawler tractor was designed. Based on operational requirements, the key components were designed and matched. An electronic architecture centered on a dual-power system, consisting of a power battery and greenhouse grid power was proposed, along with a corresponding power switching control strategy. The crawler tractor's virtual prototype model was established by using RecurDyn software, and dynamic characteristic simulations were conducted for its straight-line driving and steering conditions. The performance testing of the prototype showed that the pre-charging system can raise the DC bus voltage to the expected value within 410 ms. During the switching process between the power battery and greenhouse grid power, the maximum voltage fluctuation rate was 9.8%, with switching time of 700 ms. The insulation resistance of the entire high-voltage system to ground was greater than 30 MΩ, demonstrating good electrical stability and operational safety. Under typical greenhouse soil conditions, the average deviation rates during straight-line travel were 4.8% in power battery mode and 5.1% in greenhouse grid power mode, with minimum turning radius of 1 168.5 mm. Under rotary tillage conditions, the maximum speed fluctuation rate of the power take-off (PTO) motor was 5.9%, and the average speed of the PTO shaft was 541 r/min, both meeting national standards. Field tests in the facility showed that the overall energy loss rate in greenhouse grid power mode was 5.2 percentage points higher than that in power battery mode. The dual-power tractor exhibited complementary advantages in continuous operation capability and mobility, providing an effective solution for power equipment in protected agriculture.
