• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.3
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• pp.211-218
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• 2005

Switched Reluctance Motor(SRM) offers the advantages of simple and robust motor construction, high speed and high efficiency over a wide operating range of torque and speed, excellent controllability. However SRM has the disadvantages of high current harmonics, and low power factor because the required output of speed and torque is produced by the discontinuous and loss of power system, and brings about the incorrect operation of electronic system. This paper deals with an energy efficient converter fed SRM system with the reduced harmonics and improved power factor. The validity of the proposed scheme is verified via experiments. We are implemented the proposed control system using 80C196KC micro-controller.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.119-119
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• 2000

In this research an induction motor vector control system was developed using Simulink and RTW(Real Time Workshop). On the Simulink window, control system is designed in the form of block diagrams, program codes are produced automatically with the RTW, then c compiler compiles the program codes. With this automatic real time program producing mechanism rapid prototyping is realized without the time-consuming manual program coding procedures. To show effectiveness of the proposed designing scheme a DSP-based induction motor vector control system was constructed and implemented

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.313-317
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• 2005

Precision motor dynamometer is requiring for nano positioning control performance recently. Particularly, linear motor is using rapidly and the dynamometer needs is increasing. In this study, a precision control dynamometer is designed using MR (Magnetic Rheological) damper. The ultra precision motor system including the driver and controller is tested using the MR damper dynamometer. This dynamometer is able to measure torque for rotary motor or traction force with linear positioning accuracy for linear motor system.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.918-919
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• 2015

Because of environmental regulations in emissions control area, the demand for ships to use LNG as fuel is increasing. Orders for domestic shipbuilders to produce LNG carriers are steadily increasing. However, major appliances such as spray pump, main cargo pump and others have been relied on imports. Therefore, development of pump motor using at cryogenic temperature is necessary. Operating temperature of an induction motor is at $-163^{\circ}C$. At this low temperature, the resistivity of a motor coil is quite different from normal ones, and so does the torque characteristics of motor. This paper presents a designing method of a cryogenic induction motor for LNG pump. The variation of resistivity of motor coil is considered in the design process. The heat source such as core-loss, hysteresis-loss and copper-loss are analyzed to prevent the LNG evaporation which may cause the motor failure.

• The KSFM Journal of Fluid Machinery
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• v.17 no.3
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• pp.19-24
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• 2014

Development of long-term mobile energy sources for mobile robots or small-sized unmanned vehicles are actively increasing. The micro gas turbine generator (MTG) is a good candidate for this purpose because it has both of high energy density and high power density, and 500W class MTG is under development. The designed MTG can be divided into 2 main parts. One part consists of motor/ generator and compressor, and the other one consists of combustor, recuperator and turbine. 500W class MTG is designed to operate at ultra-high speed of 400,000 rpm in high turbine temperature over $700^{\circ}C$ to improve the efficiency. Because the magnetism of NdFeB permanent magnet for the motor/generator could be degraded if the temperature is over $150-200^{\circ}C$, MTG needs the thermal insulation to block the heat transfer from combustor/turbine side to motor/generator side. Moreover, the motor/generator is allocated to get the cooling effect from the rapid air flow by the compressor. This study presents the experimental results to verify whether the thermal insulator and air flow are effective enough to keep the motor/generator part in the low temperature less than $100^{\circ}C$. From the motoring test by using the high temperature test rig, it was confirmed that the motor/generator part could maintain the temperature less than $50^{\circ}C$ under the condition of 1.0 bar compressed air.

• The Korean Journal of Pain
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• v.19 no.2
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• pp.299-302
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• 2006

Segmental zoster paresis is characterized by focal, asymmetric motor weakness in the myotome corresponding to the dermatome of the rash. A 73-year-old man, who presented with severe right shoulder pain and shoulder girdle muscle weakness, was diagnosed with segmental zoster paresis involvement of the C5⁣-C6 motor roots as a complication of herpes zoster. Girdle muscles (supraspinatus, deltoid and infraspinatus) atrophy had developed in his right shoulder. An MRI showed rotator cuff tearing in his right shoulder; therefore, an arthroscopic rotator cuff repair was performed. Herein, this case is presented to emphasize the importance of considering post-herpetic segmental motor paresis in the differential diagnosis of acute painful motor weakness of the upper extremities.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.1
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• pp.42-53
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• 1996

The paper presents a speed control system of vector controlled induct- ion motor using neural networks. The main feature of proposed speed control system is a Neural Network Controller(NNC) which supplies torque current to induction motor and Neural Network Emulator(NNE) which captures the forward dynamics of induction motor. A back propagation training algorithm is employed to train the NNE and NNC. In order to determine the NNC output error, plant(induction motor) output error can be back propagated through the NNE. The NNC and NNE for speed control of vector controlled induction motor is carried out by TMS320C30 DSP and IGBT current regulated PWM inverter. Through computer simulation and experimental results, it is verified that proposed speed control system is robust to the load variation. (author). refs., figs.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.4
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• pp.391-396
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• 2009

In this paper, a control algorithm for DC-Link voltage unbalancing compensation of a four-switch inverter for a three-phase BLDC motor drive is proposed. Compared with a conventional six-switch inverter, the split source of the four-switch inverter can be obtained by splitting DC-link capacitor into two capacitors to drive the three phase BLDC motor. The voltages across each of two capacitors are not always equal in steady state because of the unbalance in the impedance of the DC-link capacitors $C_1$ and $C_2$ or the variable current flowed into the capacitor's neutral point in motor control. Despite the unbalance, if the BLDC motor may be run for a long time the voltage across one of the capacitors is more increased. So the unbalance in the capacitors voltages will be accelerated. As a result, The current ripple and torque ripple is increased due to the fluctuation of input current which flows into 3-phase BLDC motor. According to that, the vibration of motor will be increased and the whole system will be instable. This paper presents a control algorithm for DC-Link voltage unbalancing compensation. The sampling from the voltages across each of two capacitors is used to perform the voltage control of DC-Link by using the feedforward controller.

• Korean Journal of Acupuncture
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• v.32 no.3
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• pp.136-143
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• 2015

This study was performed to comparative investigate the distribution of primary sensory and motor neurons associated with Cheonji(PC1) acupoint by using neural tracing technique. A total 4 SD rats were used in the present study. After anesthesia, the rats received microinjection of $6{\mu}l$ of cholera toxin B subunit(CTB) into the corresponding sites of the acupoints Cheonji(PC1) in the human body for observing the distribution of the related primary sensory neurons in dorsal root ganglia(DRGs) and motor neurons in the spinal cord(C3~T4) and sympathetic ganglia. Three days after the microinjection, the rats were anesthetized and transcardially perfused saline and 4% paraformaldehyde, followed by routine section of the DRGs, sympathetic chain ganglia(SCGs) and spinal cord. Labeled neurons and nerve fibers were detected by immunohistochemical method and observed by light microscope equipped with a digital camera. The labeled neurons were recorded and counted. From this research, the distribution of primary sensory and motor neurons associated with Cheonji(PC1) acupoints were concluded as follows. Muscle meridian related Cheonji(PC1) are controlled by spinal segments of C5~T1, C6~T4, respectively.

• Proceedings of the KIEE Conference
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• 1999.07f
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• pp.2758-2760
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• 1999

ASIC chip design for motor control has been a subject of increasing interest since effective system-on-a-chip design methodology was developed. This paper investigates the design and implementation of ASIC chip for speed control of induction motor using VHDL which is a standarded hardware description language. The presented system is implemented using a simple electronic circuit based on FPGA.