• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1058-1063
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• 2004

This paper presents a new approach regarding thermal characteristics associated with a design of the high efficiency motor. Electrical conduction materials, such as coil and aluminum embedded in the core generate high heat exerting negative influence on both lifetime and performance of machine. Thus, it is necessary to design high efficiency motor considering heat transfer in order to improve motor performance and to be protected against overheating. In this paper, firstly, numerical analysis of electromagnetic field is carried out by the nonlinear transient finite element method (FEM). Secondly, the linear static FEA of magneto-thermal field is implemented by applying source current computed by the nonlinear transient analysis. FE results are validated in terms of electromagnetics and heat transfer by experiments. And then, the pseudo-transient topology optimization using a multi-objective function is performed. The proposed method is applied to a squirrel cage single-phase induction motor of the scroll compressor.

• Journal of Power Electronics
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• v.6 no.3
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• pp.214-225
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• 2006

The design and performance analysis of a reduced rating autotransformer based thirty-pulse AC-DC converter is carried out for feeding a vector controlled induction motor drive (VCIMD). The configuration of the proposed autotransformer consists of only two single phase transformers, with their windings connected in a T-shape, resulting in simplicity in design, manufacturing and in a reduction in magnetics rating. The design procedure of the autotransformer along with the newly designed interphase transformer is presented. The proposed configuration has flexibility in varying the transformer output voltage ratios as required. The design of the autotransformer can be modified for retrofit applications, where presently a 6-pulse diode bridge rectifier is used. The proposed thirty-pulse AC-DC converter is capable of suppressing less than $29^{th}$ harmonics in the supply current. The power factor is also improved to near unity in the wide operating range of the drive. A comparison of different power quality indices at AC mains and DC bus is demonstrated in a conventional 6-pulse AC-DC converter and the proposed AC-DC converter feeding a VCIMD. A laboratory prototype of the proposed autotransformer based 30-pulse AC-DC converter was developed with test results validating the proposed design and system.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.11a
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• pp.295-299
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• 2007

This paper presents the photovoltaic(PV) water pumping system with a maximum power point tracking(MPPT). The wale- pumping system uses a variable speed single phase induction motor(SPIM) driven a centrifugal pimp by field oriented control(FOC) inverter. The MPPT using a DC-DC converter controlled the duty cycle to track maximum power from PV under different insolation conditions. The duty cycle directly relate with a flux producing current control($i_{ds}$). The FOC inverter uses a current control voltage source inverter(CC-VSI). The simulation results are shown that the characteristics and performance of drive system, which varies as each conditions of light by expresses in voltage ($V_{dq}$), current($I_{dq}$), speed of motor and torque.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.692-694
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• 1992

This paper describes a robust flux bonging scheme which utilizes the windings of the machine itself to implement field orientation control of SLIM (Single-sided Linear Induction Motor). By subtracting the voltage across adjacent motor coils of the same phase which are named STATOR TAPPED COIL, a flux signal is obtained which is insensible to stater resister drop at a low speed that exerts a bad Influence on field orientation. The method using STATOR TAPPED COIL has been implemented at SLIM in our laboratory, and experimental results are being scrutinized.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.6
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• pp.254-261
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• 2003

This study investigates magnetic circuit design of the Single-phase Line-start Permanent Magnet Synchronous Motor (LSPM) to develop the characteristics in steady state. In this paper, the saliency ratio, that is the ratio of q-axial inductance to d-axial inductance, and the inductance difference between q-axial inductance and d-axial inductance are increased. Design factor is selected permanent magnet position and rotor diameter. The analysis method of the synchronous motor on d-/q- axis coordinates is used for the positive component and the equivalent circuit of the induction motor is applied for the negative component analysis. Back-emf and d-q- axial inductance is analyzed by using 2 dimensional Finite Element Method (FEM). Characteristic analysis results with variation of design factor are reflected magnetic circuit design of LSPM. The characteristics of design model are compared with the characteristic of initial model.

• Proceedings of the KIEE Conference
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• 1990.11a
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• pp.37-42
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• 1990

In order to obtain optimal design criteria and operating parameters, a Single-sided Linear Induction Motor (SLIM) is analysed by using a 2-D finite element method with magnetic and current vector potential. In the analysing procedures, the governing equation is derived from Maxwell's equation combined with the magnetic vector potential. As a forcing term, 3-phase voltage source is employed using the Kirchhoff's voltage law in order to look into effects of the unbalanced 3-phase currents and air gap flux density. Also, 2ndary eddy current distribution, longitudinal end and transverse edge effects are in turns visualized by flux lines in 3 different analysing planes as functions of frequency and input power.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.1212-1214
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• 2000

A new soft-switching PFC-Inverter for Induction Motor's operation with single phase or three phase medium size is proposed. In order to improve the power factor and the efficiency, in this paper, the ZVT topology in the conventional PFC-Inverter is adopted. So, the operation mode of the proposed ZVT PFC-inverter is analyzed and the optimum circuit is designed. At last, the PSPICE simulation and experiment results are presented in order to verify the validity of the proposed circuit.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.1987-1989
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• 1998

A single phase induction motor is predominant in fractional horsepower rating and is widely used in home and industrial equipment. For example, these motors provide the motive power to washing machines, fans, refrigerators, etc. In this paper has presented the design and implementation of a microcontroller software - based self - starting SPIM. The control algorithm used in the experimentation employed simple control strategies which enabled a single chip programmable microcontroller to execute both the self - starting and self - detecting control of SPIM with relatively simplified hardware.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.837-839
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• 2000

Capacitor-run single induction motors have the unbalanced elliptic rotating magnetic field so that it is difficult to analyze the characteristic and calculate the accurate slot leakage reactance of the rotor with the closed slot by using the lumped parameter. In this paper, the characteristic is analyzed by the symmetrical coordinate method in terms of the lumped parameter coupled with the numerical analysis. The secondary parameters are calculated by the one slot pitch boundary condition applying to Finite Element Method (FEM). The analysis results are compared with experimental ones.

• Proceedings of the KIEE Conference
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• 2003.04a
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• pp.224-227
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• 2003

Single phase induction motor(SPIM) is one of the most widely used type of low power AC motors in the world, especially for domestic or commercial applications where a three phase power supply is not available. Fractional horse power of the SPIM have no starting torque their own. So there are several ways of starting SPIMS. The most common type is the starting capacitor installed in series with the auxiliary winding to increase the starting torque. Also, the auxiliary winding is disconnected once the speed of the motor reaches 70 to 80 [%] of the rated speed. In the conventional systems, this function is conducted by a centrifugal switch. But the mechanical centrifugal switch has many problems such as switch malfunction. This paper presents the starter design of SPIM capacitor starting switch using microcontroller.