• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.908-911
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• 1993

The single-Phase induction motor is widely used in many light duty applications. especially in home and the office. At present, many applications which use these motor require continuously adjustable speed control. In the general, the speed control of single-phase induction motor is accomplished at a few discrete speeds by using tapped-windings, pole switching or gear. These techniques is inefficient and complicated. In this paper, auxiliary winding voltage phase angle of single-phase induction motor is used to continuously adjust electromagnetic torque. The analysis includes the determination of the relationship between the auauxiliary winding voltage phase angle and torque. Simulation results of the motor's torque-speed characteristics using the controlled auxiliary winding supply are shown and discussed. The drive is tested using a dynamometer to experimentally verify the results of the theory and simulations.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.89-91
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• 1994

The Development of A.C. Induction Motor for Railway Rolling Stock. The traction motor is designed as 4-pole induction motor with self ventilation. The winding insulation is throughout of materials of class H. The rotor is designed as a squirrel rotor with copper bar. The rotor speed is detected by means of a speed sensor.

• Proceedings of the KIEE Conference
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• 2002.11c
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• pp.365-369
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• 2002

In this paper, DC motor controller has been designed by using SoC. SoC is short for System on a chip. This is a methodology that both a processor and some applications are integrated in a chip. In order to design this system based on SoC, PIC 16C57 has been selected as a processor because it has not too many instruction sets and simple data path named a harvard structure. And motor control module has been programmed by using VHDL. The advantages of the design based on SoC are as follows: simple structure, high speed working, easily verifying and simulating the system.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.3
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• pp.123-127
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• 2004

Mode conversion type ultrasonic rotary motor using bolt tightened Langevin type vibrator was studied. Driving frequency of the motor, displacements and elliptical trajectories at tip of the coupler were simulated by finite element analysis program (ANSYS). Speed and torque of the fabricated motor were measured as functions of input voltage and load. As results, from FEA the driving frequency of 40.8[kHz] and useful elliptical trajectories were found. Fabricated motor rotated clockwise at frequency of 38.2[kHz]. Speed and torque of the motor were increased when the input voltage was increased. Maximum speed, torque and efficiency were 75[rpm], 0.14[Nm] and 6.28[％], respectively.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2002.05a
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• pp.10-13
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• 2002

In this study, we used a 16-bit microprocessor, 80C196KC for a control part in order to develop a multi-functional wheel-chair system, and implemented a joy-stick to control this system. For the complete system, we used a commercial electromotive wheelchair as a basic plant, and applied an encoder to get the rotating number of the motor to transfer data to the MCU to control the motor. We used PWM (Pulse Width Modulation) method to control the wheel-chair motor where a H-bridge circuit was configured. We used the fuzzy control algorithm for the operation of DC motor, which was attached to the electromotive wheelchair and manipulated following the change of the joystick position while a user was controlling the Joystick. He also could control the speed and direction of DC motor as well as control position information.

• 전기의세계
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• v.21 no.2
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• pp.9-19
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• 1972

The transient characteristics of separately excited d-c motor driven by thyristor d-c chopper is studied in this paper. The armature controlled system is applied. As a result of theoretrical analysis the following conculsions were drawn: (1) For the transient analysis, it is recognized that the state transition analysis is a more general method and powerful tool than the state equation method or signal flow graph method, although it includes iterative matrix calculations. And the system is dealt with a finite width sampled-data system in the state transition analysis. (2) The transient characteristics of the motor angular velocity and its torque to the sampling duration variation are compared with those due to the amplitude variation of d-c chopper voltage as follows. The attenuation rate of the transient characteristics is equal in both cases, but the initial value of the transient characteristics in former case is greater than in latter case. (3) The roots of characteristics equation of the system lie inside the unit circle of the Z-plane. Therefor the system is stable. Further it is found that as the sampling duration is decreased the relative stability is lessened.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.2073-2074
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• 2011

In this study, an algorithm for diagnosis of dc motor with winding open fault is suggested. A dc motor used in this paper, is consisted of a permanent magnet field stator, double 16-turn series winding rotating armature with 12-slot, brush and 12-commutator, etc. A current signal of dc motor which has brushes and commutatorswas considered for fault diagnosis. By commutation, this current signal shows different wave form according to the fault condition of the motor. In this study, operation of the data was easily through simplification of the current signal by the signal processing. Computation method is presented reference value($C_{dv}$) for diagnosis of winding open fault and verified through experiments that can be diagnosed using the reference value($C_{dv}$).

• 전기의세계
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• v.26 no.6
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• pp.48-54
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• 1977

The object of this work is to study the optimal control strategy of constant speed characteristics for a D.C control motor under influence of disturbance. In the course of the analysis, the linearization and time invariance schemes on motor dynamics are presumed throughout under certain prescribed conditions and the performance measure for optimality is assumed to be quadratic in state and the control effort, with the initial and final time specified. When the motor speed is deviated from a stationary operating point by any external disturbance, the optimal continuous feedback control law is investigated by the application of the calculus of variation and realizability of the required control meachanism is suggested. Finally, the comparative study of the speed reasponses of the motor, with and without the optimal control effort is also presented to confirm the obtained results.

• Proceedings of the KIEE Conference
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• 2000.11b
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• pp.300-302
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• 2000

There are two kinds of the synchronous motor, one is an induction type motor started without a driving system, the other is the one started with an external driving system. but, both are complicated. Nowadays, in order to devoid for the synchronous motor being complicated in design, line start permanent magnet(LSPM) motors are being developed. The LSPM motor is composed of the rotor that has interior permanent magnet and aluminum bar instead of general rotor. In this paper, we analyzed the characteristics of the LSPM motor which has both characteristics of an induction motor and a synchronous motor, and we compared the the LSPM motor characteristics with the induction motor.

• Nutrition Research and Practice
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• v.11 no.1
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• pp.57-63
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• 2017

BACKGROUND/OBJECTIVES: The level of serum albumin is an index of nourishment care and management. However, the distribution and correlates of serum albumin levels among individuals with motor disorders have not been reported until now. Therefore, we examined the distribution and correlates of serum albumin levels among individuals with motor disorders. SUBJECTS/METHODS: A cross-sectional study on 249 individuals with motor disabilities (144 men, mean age: 51.4 years; 105 women, mean age: 51.4 years) was conducted at five institutions in Ibaraki Prefecture, Japan in 2008. The results were compared with data from the National Health and Nutrition Survey. RESULTS: The mean serum albumin levels were $4.0{\pm}0.4g/dL$ for men and $3.8{\pm}0.5g/dL$ for women. Overall, 17 (11.8%) men and 25 (23.8%) women had hypoalbuminemia (serum albumin level ${\leq}3.5g/dL$); these proportions were greater than those among healthy Japanese adults (${\leq}1%$). Low serum albumin level was related with female sex, older age, low calf circumference, low relative daily energy intake, low hemoglobin (Hb), low blood platelet count, low high-density lipoprotein cholesterol (HDL-C), low $HbA_{1c}$, and high C-reactive protein (CRP) levels. The strongest correlates, based on standardized betas, were Hb (0.321), CRP (-0.279), and HDL-C (0.279) levels. CONCLUSIONS: These results indicate that the prevalence of hypoalbuminemia is higher in individuals with motor disabilities than in healthy individuals and that inflammation is a strong negative correlate of serum albumin levels. Therefore, inflammation should be examined for the assessment of hypoalbuminemia among institutionalized individuals with motor disabilities.