Sang-Hwan Ham

Influence of the Construction of Secondary Reaction Plate on the Transverse Edge Effect in Linear Induction Motor

In this paper, linear induction motor is analyzed by 3-D finite-element method (3-D FEM) to consider influence of construction of secondary reaction plate on the transverse edge effect. A effective 3-D analysis model for considering the transverse edge effect caused by the finite widths of the primary and the secondary is not only proposed, but also the simple method measuring the transverse edge effect by using the patterns of currents induced in the secondary reaction plate is proposed. With this effective analysis method, various models with overhang and cap have been analyzed to consider the relationship between the construction of secondary reaction plate and the transverse edge effect.

Method for Analyzing Vibrations Due to Electromagnetic Force in Electric Motors

In this paper, a method for predicting vibrations due to an electromagnetic force from among the other types of vibrations that occur in an electric motor is proposed. Among electromagnetic forces, the forces applied in the radial direction were separated into their spatial and temporal harmonic components for developing the vibration-prediction method. Each separated radial force densities acts as a vibration source and generates vibrations combined with the mechanical characteristics of the motor. The separation of vibration sources makes it possible to predict the magnitude of the vibration velocity occurring in the motor. This enables optimal motor design considering vibration. To this end, a description explaining the characteristics of electromagnetic vibrations that occur in an eight-pole nine-slot permanent magnet synchronous motor has been provided in this paper as an example. In addition, the proposed method was verified by comparing the obtained vibration velocity with that obtained through electromagnetic-vibration coupled analysis.

Design and comparison between IM and PMSM for hybrid electrical vehicles

Considering the development and the prototype presentations of electrical and hybrid electrical vehicles over the last decade, one can see that several machine types were applied the direct current machine (DC), induction machine (IM), the permanent magnet synchronous machine (PMSM), and the switched reluctance machine (SRM). However many comparison study shows the IM or PMSM is suitable for hybrid propulsion system [1]–[4] and this type of motor is mostly adopted in the automotive industry. The IM is generally adopted in the USA and Europe while on the other the PMSM is adopted in Japan. It is very hard to say which one is better but it depends on vehicle constraint, for example, output power, power density, efficiency, so on. In this paper, the two type of machine is compared in different output power. It shows the power density as increasing output power, and it discusses the critical issue of the iron loss according to the output power.

Study on reduction of transverse edge effect of single-sided linear induction motor for transportation system

The edge effect of the secondary reaction plate is influenced on performances of single-sided linear induction motor(SLIM). Considering shapes of the secondary reaction plate, it will be improved the thrust force of SLIM. Thickness and overhang length of reaction plate are weighty design factors for reducing the transverse edge effect. For the optimal design of secondary reaction plate of SLIM, magnetic equivalent circuit is used [1]. Two and three dimensional finite element analysis (FEM) is applied for validation of design parameters. And SLIM testing machine is used for validity of design optimization.

Design and Analysis of the Eddy Current Brake with the Winding Change

This paper is a study of the eddy current brake designed to replace the air brake of railway application. The eddy current brake has the advantage of being able to take a high current density compared to the other application because this brake is used for applying brakes to the rolling stock for a shorter amount of time. Also, this braking system has the merit of being able to take a high current density at low speed rather than at high speed, because the heat generated by the low speed operation is less than that of the high speed operation. This paper also presents a method of improving the output torque of the eddy current brake at low speed operation through a change of the winding as well as the basic design.

Optimal rotor structure design of claw-pole alternator for performance improving using static 3D FEM coupled-circuit model

This paper presents a study on static 3D finite element method (FEM) coupled-circuit model of a 3Kw claw-pole alternator. To derive the Optimal rotor structure, Magneto static 3D FEM used to define representation of the airgap flux density and phase inductance including magnetic saturation effect and leakage flux. Coupled-circuit model is alternator/rectifier system which based circuit analysis program. The static 3D FEM coupled-circuit model compare with transient simulation result, which proves to be coherent.

Design and performance analysis of outer rotor Fan-type PMSM for power density improvement

This paper is about designing non-rare earth permanent magnet motor to be used as direct drive motor (DD motor). Generally, DD motor requires high degree torque, so it is necessary to design big air-gap diameter with outer rotor type motor which can use many poles. Therefore, this research suggested a model that can be designed as outer rotor type motor by using non-rare earth magnet. Also, this paper analyzed and predicted performance of outer rotor Fan-type PMSM (Permanent Magnet Synchronous Motor) through magnetic equivalent circuit.

Design of Fan-shape Type PMSM for Improving Efficiency of Non-rare Earth Motor

The rare earth output is concentrated in limited number of countries including China. Also the necessity for development of non-rare earth motor is getting signified due to the rapid increase of rare earth price and resource weaponizing policies. Non-rare earth motor is generally designed as spoke type PMSM (Permanent Magnet Synchronous Motor) in order to maximize the power density. Such spoke type PMSM has advantage in concentrating the flux but demonstrates lower efficiency compared to permanent magnet using Nd (Neodymium) permanent magnet. Therefore, applications with strong necessity for efficiency need rotor structure having improved efficiency compared to spoke type PMSM. Hence, this study suggested fan-shape type PMSM with somewhat lower power density but maximized efficiency. Fan-shape type PMSM is a rotor shape demonstrating outstanding reduction of iron loss compared to existing spoke type. Thus, this study analyzed the improvement of efficiency and reduction of loss arising from the suggested shape through parameter calculation.

A Study on Design of Linear Induction Motor in Dynamic Tester for Catenary-current Collection

This paper presents design process of linear induction motor in dynamic tester for catenary-current collection. To minimize length of rail for dynamic tester for catenary-current collection, accelerating performance of the linear induction motor is very important. So the design process of linear induction motor considered in this paper is different with general design process of linear induction motor, because dynamic tester has three type driving region, as accelerating region, constant speed region, and braking region. Considering accelerating performance of motor, distance and time from starting point to constant speed region were concerned for load condition of motor. Designed linear induction motor was analyzed by 2-dimensional finite element method. Using mechanical dynamics simulation with analysis result of 2-dimensional finite element method and accelerating performance of designed motor was proved.

A Study of Winding Design for Capacitor Run Single phase Induction Motor

This paper is concerned with winding design in capacitor-run single phase motor. Winding design in single phase induction motor is more complicated than that in three phase induction motor, because of using concentric winding in the single phase. Various winding designs are possible, and accordingly layout of the slot is calculated by formula. And then accurate design of winding is available. Using the design process in this paper, we can get the base model with slot layout and turns of windings of 1.12 kW single phase induction motor, and it is verified by finite element analysis. In this paper, winding design and winding layout of single-phase induction motor using concentric winding are suggested.