Pil-Wan Han

A Technique of Torque Ripple Reduction in Interior Permanent Magnet Synchronous Motor

One of the advantages of interior permanent magnet synchronous motors compared to surface permanent magnet synchronous motors is its convenience when modifying the air gap flux density of permanent magnets. This paper introduces a technique of torque ripple reduction by modifying the shape of the rotor to modify the air gap flux density. Three types of rotor surfaces, such as conventional round, slightly cut, and smoothed cut shape, are investigated. The average torque, torque ripple, cogging torque, phase back-EMF, and air gap flux density distribution are analyzed and compared through finite element analysis (FEA). The validity of the proposed model is also verified by comparison between analysis results and measured results.

Optimizing Design Variables for High Efficiency Induction Motor Considering Cost Effect by Using Genetic Algorithm

The characteristics of an induction motor vary with the number of parameters and the performance relationship between the parameters also is implicit. In case of the induction motor design, we generally should estimate many objective physical quantities in the optimization procedure. In this article, the multi objective design optimization based on genetic algorithm is applied for the three phase induction motor. The efficiency, starting torque, and material cost are selected for the objectives. The validity of the design results is also clarified by comparison between calculated results and measured ones

Multiobjective optimization of three-phase induction motor design based on genetic algorithm

The characteristics of an induction motor vary with the number of parameters and the performance relationship between the parameters also is implicit. In this article, the multiobjective optimization technique based on the genetic algorithm and sizing equation is applied for the three phase induction motor. The electromagnetic losses and the locked torque are selected for the objectives. The validity of the design results will be also clarified by comparison between calculated results and measured ones.

General Characteristic of Fractional Slot Double Layer Concentrated Winding Synchronous Machine

The concentrated winding configurations offer significant advantage for reducing end windings. These machines are generally used in low speed high torque application due to relatively low copper loss. However, numbers of fractional slot construction make the designer hard to properly choose pole and slot numbers for the certain application. This paper provides the general information of possible fractional slot concentrated double layer winding machine.

Application of flux reversal principle for axial flux permanent magnet machines

Applications of flux reversal machine can be found both for linear and radial flux machines. For axial flux machines, only one application is reported considering a two phase machine. In general, flux reversal effect can produce higher back electromotive forces than other topologies for the less amount of permanent magnets and thus can increase the performance of the machine. Combining the axial structure with the flux reversal effect feature allows higher power density machines suitable for high speed or low speed direct drive applications. Proposed model has a 12-slot stator and a 16-pole variable reluctance rotor. Nd–Fe–B magnets are fixed on the surface of the pole of the stator. The objective of this article is to present an effective method for the design and performance prediction for the axial flux reversal configuration. Basic dimension equations are presented and a two-dimensional equivalent model based on finite element analysis is used for the reduction of the simulation time.

Multi optimization of high efficiency induction motor considering cost effect

The characteristics of an induction motor vary depending upon the number of parameters and the performance relationship between the parameters is also implicit. In the case of the induction motor design, we should generally estimate the many objective physical quantities in the optimization procedure. In this article, the multi objective design optimization based on a genetic algorithm is applied for a three phase induction motor. The efficiency, starting torque, and material cost are selected as the objectives. The validity of the design results is also clarified by comparison between the calculated results and the measured ones.

Approximate optimization for minimum torque ripple of three phase switched reluctance motor using response surface modeling

The approximate optimization based on a response surface modeling has been applied to the optimum design for obtainingflat torque of switched reluctance motor, which has highfluctuating torque due to its inherent salient structure. In order to reduce the fluctuating torque ripple causing noise and vibration, an optimization design technique has been introduced and investigated to find geometric and electric variables by means of combining finite element analysis considering driving circuits and response surface modeling. In this research an effective optimization method based on a response surface modeling has been used to overcome the modeling noise in formulating an objective and constraint and the cumulative numerical inaccuracy.

Design parameters and characteristics of aluminium and copper die casting induction motor for high efficiency

A copper die casting motor (CDM) has better design flexibility than an aluminum die casting motor (ADM) because of the higher conductivity of copper. However, CDM has an economic and manufacturing weak point due to the high cost of copper and its high melting temperature compared to aluminium. This paper describes a comparison of the design parameters, specifications, performances and material cost between CDM and ADM of 2.2 kW 4P, 5.5 kW 4P, 7.5 kW 4P.

The optimal design for improving efficiency of the three phase induction motor

This paper presents the design of some factors of three phase induction motor to maximize the efficiency using the design of experiments (DOE). The fractional factorial designs are used for the screening six design factors and the response surface methodology (RSM) is applied to get the efficiency-maximized points from the screened four factors. The design is also performed to consider the flux density of the stator and rotor teeth. The simulation based on equivalent circuit of induction motor is used to obtain the responses for DOE. From simulation results, the efficiency of the initial model can be improved by 3.3% without increasing motor volume and electrical steel grade.

Sensorless control using improved stator flux estimator for high-speed induction motors

In this paper, a sensorless control scheme using improved stator flux estimator for high speed induction motors has been proposed to compensate a Programmable Low Pass Filter. This paper has analyzed the affect between the estimated speed error and the phase error of the stator flux in high speed range. The estimated speed error compensation scheme has also proposed. The validity of the proposed schemes has been proven by the simulation and experiment results.