Kyung-Pyo Yi

Analysis and Design of a Multi-Layered and Multi-Segmented Interior Permanent Magnet Motor by Using an Analytic Method

Although demand for the multi-segmented and multi-layered (MSML) interior permanent magnet (IPM) motor is high, the analytic method for this motor has not yet been proposed. The finite element method has been used in the analysis and design of the MSML IPM motor, even though it takes much time to perform. To solve this problem, the correct and rapid analytic analysis method for the MSML IPM motor is proposed in this paper. This method is called the MCC method because it is the combination of the Magnetic equivalent circuit, Conformal mapping to consider slotting effect, and Concentration flux of IPM. Furthermore, the feasibility of the optimization of the MSML motor by using the proposed MCC method is verified in this paper.

Design of HTS Toroidal Magnets for a 5 MJ SMES

A 2.5 MJ Superconducting Magnetic Energy Storage System (SMES) is being developed as a national R&D project in Korea. It is in 2nd phase of total 3 phases program. In phase 1, we developed a 600 kJ SMES which had the maximum storage over 1 MJ. Its magnet was an HTS solenoid, whereas the HTS magnet for phase 2 is a toroid which is composed of 28 HTS double pancake coils. The final target of phase 3 is to develop a 5 MJ SMES, which will start from next year. The operating temperature of the HTS magnet will be below 20 K by conduction cooling. In this paper, we present and compare conceptual designs of the magnet in the shape of toroid and the configuration of serial connection of two 2.5 MJ toroids. The most important design criterion is to minimize the total length of HTS conductors.

Characteristic Analysis of an Traveling Wave Ultrasonic Motor using a Cylindrical Dynamic Contact Model

The traveling wave ultra-sonic motor (TWUSM) is operated through the frictional force between the rotor and the stator. Hence, the contact mechanism must be analyzed to estimate the performance of the motor. However, the nonlinearity of the contact mechanism of the TWUSM makes it difficult to suggest a proper contact model and a characteristic analysis method. To address these problems, a novel contact model is proposed here. It is termed the cylindrical dynamic contact model (CDCM) in this research. A motor performance estimation method is suggested using the CDCM, an analytical method, and a numerical method. The feasibility and usefulness of the suggested characteristic analysis are verified through experimental data.

A Design Methodology for Toroid-Type SMES Using Analytical and Finite-Element Method

In this paper, a design methodology for toroid-type superconducting magnetic energy storage system using the analytical method and data table from finite element analysis is proposed. The method simplifies the model, and uses analytically derived equations to calculate the energy and center flux density. In order to determine the number of turns and current using the analytic process, perpendicular flux density and parallel flux density are obtained from the data table. A 2.5-MJ toroid-type superconducting magnetic energy storage system is designed using the proposed method.

A Novel Sequential-Stage Optimization Strategy for an Interior Permanent Magnet Synchronous Generator Design

For an optimal design of an interior permanent magnet synchronous generator (IPMSG) for range the extended electric vehicle (REEV), many design variables and objective functions should be considered. Conventional optimization methods like the Taguchi method and multiobjective optimization algorithm have completeness or calculation time problems when solving the many design variables and objectives problems. To address these problems, a sequential-stage optimization strategy (SSOS) is proposed. In the first stage of the SSOS, the initial design result considering the various objective functions is derived by using the Taguchi method. In addition, the sensitive design variables are sorted through the calculation of synthetic signal to noise. In the second stage, the optimal solution for the sensitive design variables is derived using the surrogate assisted genetic algorithm (SAGA). The SAGA not only obtains an accurate and well-distributed Pareto front set but considerably reduces the number of function calls as well. In the last stage, the uncertainty consideration based on the worst-case scenario is applied to derive the robust optimal solution. By applying the proposed optimization strategy to the optimal design of IPMSG for REEV, an optimal solution is derived with fewer function calls, and the feasibility of the proposed optimization is verified by experimental results of manufactured generator.

Dynamic analysis and design of an armature for an inter-locking system of a magnetic contactor

A magnetic contactor (MC) using permanent magnets has a critical problem. When an unintended external force, such as an earthquake or a shock, is applied to the mover, the MC can be closed unexpectedly. To address this problem, the inter-locking system is proposed for the permanent magnet (PM) type MC in this research. Hence, the reliability of the PM type MC is improved significantly via the proposed inter-locking system.