• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.3 no.1
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• pp.65-72
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• 2008

Objects : This study was to report a clinical effect of Chuna Treatment for Cervical Myelopathy due to disc herniation. Methods : The patient was diagnosed as Cervical Myelopathy due to disc herniation through Cervical spine MRI and treated by cervical traction technique of Chuna Treatment with conservative management. JOA score(Japanese Orthopedic Association score), Recovery rate of Hirabayashi, VAS(Visual Analogue Scale), Dynamometer score, ROM(Range of Motion) and Motor weakness Grade were used. Results and Conclusion : JOA score, VAS, Dynamometer score, ROM and Motor weakness Grade were improved and Recovery rate was 100%.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.52-54
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• 1997

This paper deals with investigating some characteristics of the inverter-driven tractive induction motor according to the various rotor slot number. 2-D time-stepped finite element method considering the inverter voltage waveform is utilized for electromagnetic field analysis. As a result, harmonics spectra of torque and bar loss are compared in each case.

• Proceedings of the KIPE Conference
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• 2010.07a
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• pp.432-433
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• 2010

본 논문에서는 직렬형 디젤 하이브리드 전기 트럭 구동을 위한 견인 전동기 제어 시스템 개발에 대해 소개한다. 높은 출력 밀도를 요구하는 복합형 전기 차량의 특성을 고려하여 매입형 영구자석 동기전동기를 선정하고, 대전류 고효율 시스템 구성을 위해 수랭식 MCU(Motor Control Unit)를 개발 하였다. 또한 빠른 토크 응답 특성과 넓은 영역의 속도 운전을 위한 약자속 제어 기법을 적용하였으며, 전체 시스템 효율을 향상시키기 위해 단위 전류당 최대 토크 제어 기법(MTPA)이 사용 되었다. 개발 된 제어 시스템 및 제어 기법을 실험을 통해 검증 하였다.

• Proceedings of the KIPE Conference
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• 2010.07a
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• pp.450-451
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• 2010

In this paper, the low-cost drive circuit of dc motor for a multipurpose small-size electric vehicle is developed. In order to change smoothly the rotating direction of dc motor for traction, the operating sequence of both the field current and the armature voltage according to the angle of a pedal of vehicle is suggested. The simulation study is carrier out to verify the proposed method, and the control system is implemented with 8-bit AVR.

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.398-402
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• 1999

In PWM inverter fed traction motor drive systems, the switching frequency is restricted and thus the electromagnetic acoustic noise is generated. To reduce such an audible noise, we propose the modified RSF(Randomized Switching Frequency)-PWM method. In the proposed RSF-PWM method, both triangular wave and sawtooth wave are used in one period as carrier waves. Because the proposed method has inherently the same property as sinusoidal PWM method, there is no problem of linearity. To verify the validity of the modified RSF-PWM method, computer simulations are carried out.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1047-1048
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• 2006

The DITC of SRM for smooth hoist driving is presented in this paper. In the hoist system, the switched reluctance motor (SRM) is applied instead of induction motor because of high efficiency and good traction characteristic. In order to improve start-up and stop performance of hoist system, the smoothing operation sequence of SRM using DITC is proposed. According to the switching sequence and hysteric band, the instantaneous torque is controlled. Since, the proposed method uses only the turn-on angle depending on variation of load and speed, a simple DITC can be implemented. The validity is proved by simulation and experiment.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1484-1488
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• 2009

This paper analyzes the noise reduction of traction motor for rolling stock. Nowadays, rolling stock becomes a attractive transportation as a friendly environment transportation. And this paper showed that vibration noise of motor coil by inverter switching frequency. That noise has influence on passenger. It is important that noise reduction for passenger in the rolling stock. In this paper, it shows that effect of variable switching frequency of propulsion inverter for noise reduction.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.433-438
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• 2003

The recent operating trains including the high speed train are mostly moving system on the rail and system use the mechanical propulsion force to drive the gear and wheel by the traction motor. Advanced countries are interested in Magnetic Levitation Vehicle and they have been studying about it continuously. Thus this paper is analyzed the feature of analysis the feature for Linear Induction Motor as the propulsion equipment of Magnetic Levitation Vehicle. And the Magnetic Levitation Vehicle is being developed for the transportation system of next generation using the Finite Element Method

• Journal of KIEE
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• v.11 no.1
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• pp.62-68
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• 2001

In this paper it is proposed an advanced modified sliding mode control of a rotor field oriented control of induction motor. The application of this unconventional control has very good results, such as disturbance rejection and nice dynamic properties. Stability can be guaranteed even in the worst situation. A conventional "sliding mode" controller is characterised by fast switching control signal, which causes the chattering of the drive system. To overcome this problem, a modified law is used, by introducing a hysteresis band and a continuous control, which modifies the conventional law. The control is accomplished with dual TMS320C44 floating-point digital signal processor. The validity of the proposed method was verified by experiment on the propulsion system simulator, used for the development of Korean High-Speed Railway Train(KHSRT).in(KHSRT).

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.239-242
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• 2001

Energy recovery in the regenerative region is very important when SRM(Switched Reluctance Motor) is used in traction drive. This is because that to reduce energy toss during mechanical breaking and/or to have a high efficiency drive during breaking. To control excitation voltage in motor operation and regenerative voltage in the generator operation in the SRM, multi-level voltage control is effective. This paper proposes multi-level inverter which is useful for motoring and regenerative operation in SRM. The proposed method is verified by experiment.