The purpose of this paper was to develop a simulation model for a 40 kW electric tractor using a powertrain based on dual motors and a planetary gear. To select motor capacity and reduction gear ratio based on the power flow for agricultural work, load data for various gear conditions were acquired and analyzed using a 42 kW engine tractor of similar capacity. Modeling was conducted using MATLAB/Simulink/Simscape. Load data acquired through actual field tests were applied as load conditions for the simulation. Simulation results confirmed that the power was transmitted through the planetary gear as the clutch and brake operated according to the work mode. The developed simulation model is expected to be used for electric tractor development.
A differential is a mechanical device that supports smooth driving, by allowing each of the two wheels, to rotate at differential speeds during a turn. This is particularly crucial for tractors, as they mainly work on the ground, often becoming stuck off-highway, or falling into pits. When the tractor wheel is stuck off-highway, it is difficult to get the wheel out, as the differential of the tractor reduces friction between the wheel and the ground surface. In order to prevent this wheel slip situation, the differential locking device, which restricts the two wheels on the axle to the same rotational speed, has been used in the axle of the tractor. In this study, analysis models of the hydraulic system and the dog clutch were developed to predict the performance of the differential locking device. Using the LMS imagine. AMEsim software, the analysis models were verified by comparing the simulation results with the experimental data. Using the models developed, the influence of the release time of the differential locking device on selected design parameters was analyzed, to determine the effect on the release time of the differential locking device. As a result, design values that will improve the performance of the differential locking device were derived.