Simulation Analysis of Motor and Battery Characteristics Using a Validated Model of an Electric Tractor

Abstract

The electrification of agricultural tractors is a key step toward improving energy efficiency and reducing environmental emissions. However, quantitative evaluation of drivetrain performance remains limited because workload data for electric tractors are scarce, while most available datasets originate from conventional mechanical tractors. In this study, a one-dimensional simulation model was developed to effectively utilize existing workload data by integrating the drivetrain and electrical characteristics of an actual electric tractor. The model combines an electrical subsystem based on field-oriented control (FOC) of a permanent magnet synchronous motor (PMSM) with a vehicle subsystem representing the mechanical drivetrain. Model validation was performed through dynamometer experiments using axle torque as input and motor responses as output, showing strong agreement with measured data. The validated model was applied to field-measured workloads to analyze motor performance, battery state-of-charge behavior, usable operating time, and operating points across various agricultural operations. The proposed simulation model enables quantitative evaluation of electric tractor performance under realistic load conditions and can be extended for co-simulation with higher-level control models. In future studies, the model will be utilized as a platform for testing and developing energy-efficient control algorithms for next-generation electric tractor systems.