Development and verification of a synchronous reluctance motor for agricultural mobile platforms

Abstract

Current trends in electrification require the development of specialized traction electric motors that combine high power density, manufacturability, and energy efficiency. Synchronous reluctance motors are a promising solution because they offer low manufacturing costs and high maintainability, which are particularly important for agricultural machinery operating under harsh conditions. (Research purpose) The aim of this study is to develop and experimentally verify the design of an energy-efficient synchronous reluctance motor with a multilayer rotor for agricultural mobile platforms and to evaluate the effectiveness of different vector-control algorithms in maximizing torque and efficiency. (Materials and methods) A three-phase 3-kilowatt synchronous reluctance motor with a four-barrier rotor was investigated. The flux-barrier geometry was designed through parametric optimization using dimensionless coefficients. The magnetic field and the main electromagnetic characteristics, including inductance, flux linkage, and losses, were calculated using the finite element analysis in FluxMotor. Experimental verification was performed on a test bench equipped with a loading device and a frequency converter. Two control strategies were compared: sensor-based vector control and sensorless vector control. (Results and discussion) The developed rotor design with four flux barriers provided high magnetic anisotropy, with an inductance ratio of 4.08, enabling a rated torque of 31.4 newton-meters to be achieved at a current of 9.61 amperes. Compared with sensorless control, sensor-based vector control increased torque by up to 9 percent and efficiency by 2–3 percent over the entire operating speed range. Under high-load conditions, the maximum recorded efficiency reached 95 percent. Comparison of the simulated and experimental data showed good agreement, with the discrepancies not exceeding 8.2 percent for torque and 7.0 percent for efficiency. The achieved characteristics make the developed motor suitable for effective use in traction electric drives of agricultural mobile platforms. (Conclusions) The developed synchronous reluctance motor meets the requirements for traction electric drives. Its high energy efficiency, reaching up to 95 percent, combined with a simple and readily manufacturable design, can reduce operating costs, increase driving range, and improve machine productivity. Sensor-based vector-control algorithms are recommended for operating modes requiring maximum torque and efficiency, which is particularly important during energy-intensive operations such as plowing and power take-off operation.