• The Transactions of the Korean Institute of Electrical Engineers B
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• v.50 no.4
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• pp.151-157
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• 2001

This paper presents an identification method of parameters of induction motor which is driven by PWM voltage inverter. The method uses least square estimation based on the step voltage input and current response. Utilizing the fact that ratio of two characteristic roots is large in the induction motor circuit, we derived two 1st-order difference equations for direct computation of parameter values. experimental results are compared with conventional motor test results to demonstrate that the proposed method is capable of estimating parameters of induction motor at standstill.

• Journal of Industrial Technology
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• v.35
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• pp.9-13
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• 2015

In this paper, a new excitation scheme is developed to increase the output torque of the sensorless BLDC(Brushless DC) motor(BLDCM), which drives fins to control the flight attitude of a guided artillery munition. The proposed scheme is based on a 12-step excitation strategy combining two-phase and three-phase excitations. The proposed 12-step excitation scheme can produce more torque than a typical 6-step scheme for the start-up and synchronous operation in the sensorless BLDCM drive. The simulation and experimental results on the sensorless BLDCM drive system to control the fin were verified the validity of the proposed scheme.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.594-596
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• 1987

In this study, a method of obtaining reasonably large and constant torque at high speed is given in order to improve the performance of the open loop controlled step motor system using the current source, thus resulting in high performance compared to the conventional current limiting using resistor and chopper.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.4
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• pp.358-363
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• 2010

This paper proposes a step-by-step method of determining the parameters of equivalent circuit which is considered the no load losses for the single phase induction motor which has the starting winding. This method is comprised of three steps, and the stator resistance which is measured by the method of voltage drop is treated as constant and the stator and the rotor leakage reactances are assumed to be the same in every step. The test results of no load and locked rotor test are used in the 1st and 2nd step, and the ratings of name plate of the motor are needed in the 3rd step. In the 1st step, the traditional equivalent circuit parameters are directly calculated by no load and locked rotor conditions. In the next step, five nonlinear simultaneous equations for five unknown parameters can be set up by no load and locked rotor equivalent circuits. These equations are solved by using the initial parameters obtained by the 1st step parameters. In the final step, three nonlinear simultaneous equations for rotor winding resistance, leakage reactance and no load losses component resistance can be set up by equivalent circuit under the rated operation. Three parameters are solved by using the 2nd step parameters. Thus, equivalent circuit parameters are gradually refined step by step. The validity of the proposed method is evaluated by comparing the computed values obtained by the equivalent circuit parameters with the experimental values of the load test.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.36 no.8
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• pp.539-546
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• 1987

In case of operating at Variable speed the induction motor by a frequency transformer, it will cause ripples in motor torque and considerably bad effects on the machines because the output side of the frequency transformer involves a great number of harmonics. This paper Presents the methods of decreasing torque ripples in induction motor and of improving current waveform, by means of forming the waveforms of output current into multi-step waveforms similiar to sinusoid, and also by means of eliminating the harmonic components maximally, in case of operating a 18-phase multi-inverter combining 3-step current source inverter.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.10
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• pp.646-651
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• 2000

Recently, the 2-phase brushless DC motor has been used in electric home appliance for low price and low energy consumption. In this paper, we analyzed a 2-phase BLDC motor using time-step finite element method. And the validity of analysis is confirmed by measuring the flux distribution on the surface of permanent magnet and back-EMF. As well, we have calculated the dynamic characteristics of target motor considering the Hall sensor position. So, we have found the optimum switching position, and improved performance of 2-phase BLDC motor.

• Proceedings of the KIEE Conference
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• 1988.11a
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• pp.21-23
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• 1988

Microstepping drive of 3 phase VR step motor with 2 phase exciting scheme is proposed. Considering the presence of harmonic components of inductance, the current reference is calculated. The experimental results show high accuracy of divided step position and resonance or instability in operating range.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.203-206
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• 1998

This paper describes the procedure of getting information about auto-tuning of PID regulator by the injection of high step input, called limited input, during a transient time of control. The key point is that system identification and control could be continuously executed. This means that the system information obtained by limited input despite of system uncertainty can be continuously applied to the PI regulator. Simulation and experiment result of brushless DC motor system having monotone increasing step response demonstrate the usefulness of proposed auto-tuning algorithm.

• Proceedings of the KIPE Conference
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• 2006.06a
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• pp.311-315
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• 2006

This paper proposes 5 phase step motor drive system has high performance dynamics with micro step control has current controller. In this paper, analog current controller has been developed to minimize system size and cost. The validity of the proposed technique is verified through experimental results of position control robot.

• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.97-100
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• 1998

In this paper, micro step driving method is used for the high performance motion control and low vibration and low noise in an X-Y axis soldering machine for factory automation. The improvement of the electrical and mechanical driving characteristic of a stepping motor is achieved by applying microstep driver.