• Proceedings of the KIEE Conference
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.597-599
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• 1992

A calculation method for predicting the instantaneous torques by the inductance profiles of a switched reluctance motor (SRM) is presented. The method considers saturation and nonlinearities in the magnetic circuits. The inductance of SRM varies complex according to the input current waveforms and rotor position angle, thus the accurate calculation technique is needed to estimate the inductance value at arbitary input current and rotor position angle. This paper describes how the inductance profiles influence the torque produced by the input current of SRM and, proposes a calculation technique of the permeabilities, reluctances, current waveforms and torques of a 6/4 3-phase SRM.

• Proceedings of the KIEE Conference
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• 대한전기학회 2001년도 하계학술대회 논문집 B
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• pp.877-879
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• 2001

The switched reluctance motor (SRM) has a simple motor construction with no rotor windings. It also has simple concentrated windings on the stator windings. Thus it is expected to be a lower cost machine to manufacture than other motors. This paper has computed an optimal parameters asking for SRM drives using by PC-SRD that was programmed by T. J. E. Miller/M. Mcgilp. According to advanced angle and dwell angle, the output, efficiency, currents and torque were computed. The experiments with 8/6 SRM have tested.

• 전기의세계
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• 제24권1호
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• pp.29-42
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• 1975

In this paper, the electrical angle between two winding axes in the stator of the capacitor motor is put optional angle, deviding the space harmonics in its magnetic field of two windings and the leakage flux into the forward revolving field and the backward one by the revolving-field theory, its equivalent circuit which consider mutual induction between two windings is depicted. In the depicted equivalent circuit, the rotor resistance for the fundamental flux is devided into the resistance for the rotor bar and endring, and the rotor leakage reactance for the fundamental is devided into the skew leadage reactance and the other, and each circuit constants for each harmonics is expressed in terms of the circuit constants for the fundamental, so it mades easy to determine the characteristics for the capacitor motor. As the circuit constant ratios to the magnetizing reactance of the fundamental are used, motors which have same circuit constant ratios should be resembled in their characteristics.

• Journal of Mechanical Science and Technology
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• 제16권2호
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• pp.155-164
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• 2002

The power steering system for vehicles is becoming essential for supporting the steering efforts of the drivers, especially for the parking lot maneuver Although hydraulic power steering has been widely used for years, its efficiency is not high enough. The problems associated with a hydraulic howe. steering system can be solved by a motor driven power steering (MDPS) system. In this study, a dynamic model and a control algorithm for the ball screw type of MDPS system have been derived and analyzed by using the method of discrete modeling technology. To improve steering feel and power steering characteristics, two derivative gains are added to the conventional power boosting control algorithm. Through simulations, the effects of the control gain on the steering angle gain were verified in the frequency domain. The steering returnability and steering torque phase lag in on-center handling test were also evaluated in the time domain.

• The Transactions of the Korean Institute of Power Electronics
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• 제6권2호
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• pp.180-190
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• 2001

In this paper, a method of reducing torque ripples caused by phase winding inductances in BLDCM(Brushless DC Motor) drives is presented. In order to compensate the inductive current delays, commutation angle is controlled by the value compensating angle varied in accordance with rotational speed. Using the microprocessor AVR 8515, the proposed compensator is implemented and experiments are done with a 4-pole 3-phase BLDCM. The results show the remarkable reduction of torque ripple at whole speed ranges.

• Transactions of the Korean Society of Automotive Engineers
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• 제8권1호
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• pp.124-134
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• 2000

The power wteering system for automobiles is becoming core popular for supporting steering efforts of the drivers, especially for a parking lot maneuver. Though hydraulic power steering has been widely used for a long time, the efficiency of that is not high enough. The motor driven power steering system can solve the problems associated with the hydraulic power steering system. In this study, dynamic model and control algorithm of the ball screw type of MDPS systenem have been derived and analysed by using the method of discrete modeling technology. To improve steering feel and power steering characteristics, the additional scheme is proposed to the conventional power boosting control algorithm. Through simulations, control gain effects to the steering angle gain in the frequency domain were verified. The steering returnability and steering torque phase lag in on-center handing test were performed also.

• Transactions of the Korean Society of Machine Tool Engineers
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• 제10권6호
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• pp.8-14
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• 2001

We develop a method to analyze dynamic behavior off multi-stage gear train system. The example system consists of three shafts supported by ball bearings at the ends of them and two pairs of spur gear set. For exact analysis, the meshing tooth pair of gear set is modeled as spring and damper having time-dependent meshing stiffness and damping. The bearing is modeled as spring. The result of this analysis is compared to that of other model having mean mesh stiffness. The effect of the excitation force by the unbalance off rotor off motor is also analyzed. Finally, the change ova natural frequency of the whole system due to the change of an angle between three shafts is compared in each case, and from this analysis, the avoiding angle for design is advised.

• Journal of Institute of Control, Robotics and Systems
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• 제3권6호
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• pp.619-625
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• 1997

In this paper, we show that the rotor position of the bifilar-wound hybrid stepping motors for the closed-loop drives is detected by the phase current measurement. We propose an instantaneous phase current equation, which is the function of electrical angle, by modeling the stepping motor including motor driving circuits. We also analyze the relationship between phase current and rotor position from the computer simulation results. We show that the information about the rotor position is obtained from the phase current amplitude and its derivatives at the instance of ${\pi}/2$ electrical angle of excitation voltage.

• Proceedings of the KIEE Conference
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.791-793
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• 2004

Voltage unbalance is generated by the load and impedance mismatching at the 3-phase 4-wire system of customer load. Voltage unbalance factor can be changed by the voltage amplitude or phase angle, and both. A small voltage unbalance is connected to high current unbalance. If the voltage unbalance is generated at the joint system of 1-phase and 3-phase load, Induction motor due to the current unbalance increase is generated loss, noise and torque ripple. In order to analyze the effect by voltage unbalance, it is necessary to the consideration of amplitude and phase angle. In this paper, We analyzed the effects that induction motor is affected by asymmetric voltage unbalance

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 한국신호처리시스템학회 2003년도 하계학술대회 논문집
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• pp.183-187
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• 2003

When a flexible arm is rotated by a motor about an axis through the arm's fixed end, transverse vibration may occur. The motor torque should be controlled in such a way that the motor rotates by a specified angle, while simultaneously stabilizing vibration of the flexible arm so that it is arrested at the end of rotation. In this paper, we propose nonlinear observer for one-link flexible am. Then based on the error dynamic equation between the plant dynamic equation and the nonlinear observer dynamic equation of the flexible one-link am, Lyapunov candidate function is applied to achieve a stable deterministic nonlinear feedback controller for the regulation of joint angle.