Future mobility is an industry that specializes in motors following common core parts such as batteries and semiconductors. Among them, the motor specialized industry constitutes a front and rear value chain from magnetic materials to finished vehicles. In this paper, we will examine the industrial technology and major issues of each sector of the motor-specialized industry value chain by analyzing R&D cases such as high output, light weight, high density, and high efficiency, along with efforts to develop technologies to stabilize the parts supply chain in the material parts sector.

Mobility motors have various applications such as automobiles, aircraft, small mobile devices, and UAM, but their common characteristics are small and high-powered. This paper explains how to apply permanent magnets to increase power density from the point of view of electromagnetic system design, change the characteristics of permanent magnets, and how to use them focusing on electric vehicles and electric aircraft motors applied to mobility motors that are recently increasing. In addition, an axial flux motor capable of realizing a high-output motor was introduced. Permanent magnets applied to high-power motors have various problems of current input and high temperature, therefore the change in the operation point of permanent magnet according to the change of the permanent magnet and the surrounding magnetic circuit has been described. Accordingly, the characteristics of permanent magnets to avoid irreversible demagnetization were discussed. High-powered axial flux motors were introduced to currently applied aircraft and motors, and the loss reduction of iron cores considered in designing motors was explained.

Recently, with the rapid spread of eco-friendly mobility, there is an increasing demand for improved driving performance, and in particular, miniaturization, high efficiency, and high performance of drive motors are becoming important factors. In order to achieve this required performance, optimization of many design factors is required, and in particular, stable control of the temperature generated in the coil part and cooling circuit design are important factors. However, predicting the heating temperature distribution of the coil from the initial design stage of the motor requires a lot of experience and know-how. This is the result of trial and error obtained through repeated processes of initial design, product manufacturing, test measurement, and modified design. Recently, a motor design method using proven commercial software analysis techniques has been widely used to reduce this complicated process and to speed up the initial design. In this paper, using CAE commercial software, we introduce motor design cases considering coil heating temperature analysis and cooling circuit design from the initial design stage of the motor.

This paper deals with an analytical approach for predicting the open-circuit magnetic field of permanent magnet machines. First, general governing equations for predicting the open-circuit magnetic field of a permanent magnet machines were derived based on the magnetic vector potential. And then, the geometric structures of the linear and the rotating permanent magnet machine were applied to the rectangular coordinate system and the cylindrical coordinate system, respectively, and this paper obtained general solutions of the magnetic vector potential. In particular, in the case of rotary permanent magnet machines, general solutions suitable for each was derived by dividing radial flux and axial flux permanent magnet machines. Based on the general solution and definition of the magnetic vector potential, the general analytical solutions for normal and tangential magnetic flux density of each permanent magnet machine were obtained. The analytical results were compared with the finite element analysis results, and the validity was verified. The analytical method presented in this paper is equally applicable to predicting the magnetic field produced by the armature coil, and can quickly and relatively accurately predict the main performance factors (torque, electromotive force, inductance, cogging torque, etc.) of the permanent magnet machines from these magnetic fields. Therefore, it is considered that it can be applied to research related to the analysis and design of permanent magnet machines.

Motors are used in automobiles and many other applications and account for a significant portion of total power consumption. Therefore, it is important to design highly efficient motors and accurately evaluate their performance. However, the finite element analysis (FEA) used for motor design cannot fully reflect the actual test environment. Therefore, it is necessary to validate the design by comparing the FEA and test data through motor testing at the final stage of motor design. Among various motor test methods, in this paper, a 15 [kW] dynamo is used to reach the measured operating point through speed control of the load motor and current control of the test motor. The back electromotive force obtained from the no-load test of motor was measured and compared to the back electromotive force constant and torque constant values calculated from the FEA. These constants allowed the torque to be predicted without performing complex load tests of motor. Mechanical losses can be calculated by separating iron losses and permanent magnet (PM) eddy current losses from the no-load losses obtained from the no-load test. The mechanical losses are reflected in the FEA results and compared with the test results to accurately evaluate the performance of the motor design.