• Journal of Electrical Engineering and Technology
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• v.9 no.4
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• pp.1309-1314
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• 2014

The measurement of stator core loss for an induction motor at each manufacturing process is carried out in this paper. Iron loss in the stator core of induction motor changes after each manufacturing process due to the mechanical stress, which can cause the deterioration of the magnetic performances. This paper proposes a new iron loss measuring system of the stator core in an induction motor, which can be applied to the case when the distribution of magnetic flux density is not uniform along the magnetic flux path. In the system, the iron loss is calculated based on the induced voltage of the B-search coil and exciting current.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.12
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• pp.1218-1229
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• 1991

The time optimal position control design can be repeatedly taken from the initial state of a dynamic system to a desired one as fast as possible in the industrial drives. In this case, an induction machine parameters will vary due to temperature, frequency, and saturation effects. In particular, the rotor resistance changes critically with temperature and frequency. These changes affect the command values of the stator current components and slip speed. There is a mismatch between the commanded variables and actual ones of the induction motor drive, and this situation leads to coupling of the vector controller from the plant, i.e. the induction motor . Consequences of such a coupling include the initiation of oscillations of the rotor flux and unsuitable switching of electromagnetic torque for the induction motor servo drive. Therefore, this paper describes a rotor resistance parameter compensating method for the induction motor, And the validity of the proposed design method is confirmed by simulation studies and experiment results.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.50 no.2
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• pp.53-58
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• 2001

This paper describes a moving mesh technique for dynamic characteristics analysis of permanent magnet linear synchronous motor with the secondary aluminium sheet. The moving mesh technique applied to the linear induction motor can be used to analyze the linear synchronous motor with the rectangular permanent magnet. But in case of the permanent magnet with taper, the shape of the permanent magnet is presented. The time-stepped finite element method is used for the dynamic characteristics simulation of the permanent magnet linear synchronous motor, The results of application example(hysteresis current controlled inverter fed control) such as thrust, current and flux plots are shown.

• Annals of Clinical Neurophysiology
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• v.9 no.2
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• pp.89-92
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• 2007

A 33-year-old women developed weakness in all limbs 3 days prior to admission. Motor examination showed decreased strength in all limbs, but sensory examination was normal. Deep tendon reflexes were areflexia. Electrophysiological examination showed conduction blocks with nearly normal conduction velocities and terminal latencies in motor nerves and normal amplitudes and velocities in sensory nerves. Her serum was positive for IgG antibodies to gangliosides GM1, GD1b, and galactocerebroside. Acute motor conduction block neuropathy may be another variant of Guillain-Barre syndrome.

• Journal of Electrical Engineering and Technology
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• v.6 no.5
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• pp.666-670
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• 2011

In this paper, a method for detecting broken rotor bar and stator winding fault in a low voltage squirrel-case induction motor using an air-gap flux variation analysis is proposed to develop a simple and low cost diagnosis technique. To measure the leakage flux in radial direction, a radial flux sensor is designed as a search coil and installed between stator slots. The proposed method is able to identify two kinds of motor faults by calculating load condition of motors and monitoring abnormal signals those are related with motor faults. Experimental results obtained on 7.5kW three-phase squirrel-cage induction motors are discussed to verify the performance of the proposed method.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.1020-1022
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• 1993

The speed control associated with do send motors for direct-drive applications of mobile robot is considered. In odor to the high-performance operation of dc servo motor, drive circuits is controlled Pulse Width Modulations. In this case, PWM driving circuit has nonliner charactristics. This circuit composed of H-type bridge with freewheeling diodes in odor to deal with storage energy of motor's inductance and also control method is developed. At resultes, speed charactristics of motor is shown lineristics. In oder to speed control of motor. The opertion of phase-locked servo system is described and a linear discrete model is developed to their behavior. Thise model discussed are the design problems, speed variation.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.175-177
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• 1994

In the overmodulation region, the operation of the three phase induction motor with a current controller is characterized by a rapid deterioration of the motor torque and speed. It is desirable to use the overmodulation strategy that extends the normal operating range even in this case. In this paper, a new overmodulation strategy is proposed for the high performance motor drives and the comparison study with two conventional methods are also described. In the proposed strategy, considering the motor dynamics, a suitable voltage vector is selected in order to extend the stable operating range in the overmodulation region. With this advanced overmodulation algorithm, the normal operating range can be extended without any extra hardware.

• Journal of Digital Convergence
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• v.14 no.12
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• pp.73-84
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• 2016

The purpose of this study is to examine the global value chain of the global automotive industry to investigate the success factors through the example of the value chain of Hyundai Motor. It looks at the value chain of the well-known Korean automaker, Hyundai Motor, to find success factors with cases. It examines the process to build the supply chain of Hyundai Motor to analyze what impact it has on the growth of Hyundai Motor to look closely at the vertical division of labor of vehicle parts manufacturers. Korea's automobile industry has been expanding cooperation between two sectors as a multifunctional promotion focusing on electronic communications technology in machinery and technology center. Through introducing the nation's first vertical integration in the sector, Hyundai Motor has secured competitiveness of cost reduction and prestige car production. Hyundai Motor has operated and established factories in the United States, India, Turkey, the Czech Republic, Russia, and Brazil. Hyundai Motor operates 51 affiliates, such as Hyundai Mobis, by restructuring, mergers and acquisitions, and building their own vertical division of labor around it. Hyundai Motor has been overcoming dependence on foreign modules businesses and maintaining the supply value chain around Hyundai Mobis.

• Physical Therapy Korea
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• v.13 no.2
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• pp.77-84
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• 2006

Although conservative management of congenital muscular torticollis (CMT) has been well documented, relatively little is known about the response to the treatment. The purposes of this case report were to describe the use of a therapeutic approach based on motor development in physical therapy intervention for an infant with CMT and to report the result of the treatment. The patient was a 20-day-old baby boy with left CMT presenting muscular mass in the left sternocleidomastoid muscle. The angle of the lateral head tilt was 20 degrees. The size of muscular mass was 5.3 mm in ultrasonography. Intervention included ultrasonic therapy, soft tissue massage, passive and active range of motion exercises, motor developmental therapy, and parent instruction. The procedures of motor developmental therapy and changes in the amount of lateral head tilt were documented using photography. The size of the mass was decreased to .3 mm before the 5-month follow-up. The patient also maintained a midline head position in the supine position and a midline head alignment during all functional activities. A therapeutic approach based on motor development is a beneficial method for reducing an asymmetrical head and neck position, and facilitating normal development as a component of physical therapy intervention.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.585-588
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• 2002

The USM uses friction between a mobile part (rotor) and a vibration part(stator), which is different from the principle of the conventional motor based on the interaction of electric and magnetic fields. In this thesis, a flat-type $L_1-B_8$ mode USM was designed and fabricated the characteristics of an ultrasonic vibration. The results of fabricated USM are as follows: (1) In case of ultrasonic motor with elastic-body of stainless, when applied voltage, frequency, pressing force of rotor were 50 [V], 27.9 [kHz], 1.5 [N], 5.0[mN m] respectively, the speed of revolution could be presented up to 0 [cm/s]. (2) In case of ultrasonic motor with elastic-body of brass, when applied voltage, frequency, pressing force of rotor were 50 [V], 21.4 [kHz], 1.5 [N], 1.4[mN m]respectively, the speed of rotor revolution was presented up to 0 [cm/s]. (3) The USM of elastic-body of stainless showing 1.17[%], somewhat low, in the maximum efficiency according to torque was superior to the USM of elastic-body of brass showing 0.34 [%]. The Flat-type $L_1-B_8$ mode USM had characteristics of typical drooping torque-speed, large torque and high speed, and operating in both directions by phase reversal.