• Journal of IKEEE
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• v.23 no.1
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• pp.224-229
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• 2019

Seat of automobile is required to support the comfort to driver and passenger during the driving. The control method of the seat position is changed from manual type to power type, which means using the motor to increase the comfort of the driver. By using the motor, several problems, such as vibration, noise, and over-current, appeared. These problems can be reduced through the control of seat motor. In this study, a control technology of four control variables, which determine profile of the input voltage applying to the seat motor, is proposed to generate the current profile having soft-start and soft-stop. The current flowing through the coil by input voltage is described by mathematical modeling of power seat. It is confirmed that optimized current profile having soft-start and soft-stop can be generated from simulation using the mathematical model.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.6
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• pp.826-831
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• 2007

In this paper, we proposed new method of soft-motor control which is control method allowing motor control within control stage by using EtherCAT which is real time motion control network of high speed. We also evaluated performance of the system and verified possibility and effectiveness of application into real system through experiments.

• Journal of Electrical Engineering and Technology
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• v.12 no.3
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• pp.1090-1100
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• 2017

This paper presents the comparison of starting current characteristics of a three-phase induction motor fed by two types of soft starters. The first soft starter under investigation is a conventional AC voltage controller on the basis of a phase-control technique. The other is the proposed asynchronous PWM AC chopper which is developed from the conventional synchronous PWM AC chopper. In this paper, the proposed asynchronous PWM AC chopper control scheme is developed by generating only two asynchronous PWM signals for a three-phase main power circuit (6 switching devices) from a single voltage control signal which is compared with a single sawtooth carrier signal. By this approach, the PWM signals are independent and easy to implement since the PWM signals do not need to be synchronized with a three-phase voltage source. Details of both soft starters are discussed. The experimental and simulation results of the starting currents are shown. It is found that the asynchronous PWM AC chopper efficiently works as a suitable soft starter for the three-phase induction motor due to that the starting currents are reduced and are sinusoidal with less harmonic contents, when being compared with the starting current waveforms using the conventional phase-control starting technique. Also the proposed soft starter offers low starting electromagnetic torque pulsation.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2378-2381
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• 2003

In recent years, fuzzy logic has received greater emphasis in the field of power electronics and motion control by virtue of its adaptive capability. A new fuzzy logic based soft-start scheme for induction motor drives close to load detection has been discussed here using microcontroller based thyristorised voltage controller. Rule based soft-start algorithm is fully realised through a software approach only. The soft-start strategy is based on the change of input impedance during starting period. The prototype has been tested under various loading conditions and found to be reliable.

• Journal of Power Electronics
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• v.18 no.6
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• pp.1720-1728
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• 2018

This paper proposes a novel soft starting algorithm by using PWM inverter technique to control an amplitude of the motor starting current at a single-phase induction motor (SPIM). Traditional SPIM starting methods such as a Split-Phase, Capacitor-Start, Permanent-Split Capacitor (PSC), Capacitor-Start Capacitor-Run (CSCR), basically cannot control the magnitude of starting current due to the fixed system structures. Therefore, in this paper, a soft starting algorithm based on a proportional resonant (PR) control with a variable and constant frequency is proposed to reduce the inrush current and starting up time. In addition, a transition algorithm for operation modes is devised to generate a constant voltage and constant frequency (CVCF). The validity and effectiveness of the proposed soft starting method and transition algorithm are verified through experimental results.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.65 no.2
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• pp.88-93
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• 2016

Soft starters are used with large induction motors in blowers, fans, pumps and the crane hoist drives. AC voltage controllers are used as soft starters in induction motors for starting and to adjust its speed. Soft-starter starting system uses phase control method of input electric source through the setting of the thyristor(SCR) firing angle ${\alpha}$, and it can control input electric source stably and continuously from beginning of starting to ending of starting. In this paper, it is verified that power stack of high-voltage with SCR series system possesses dielectric strength and input electric source is controlled stably by phase control. Especially, from the driving experimental of proposed soft-starter operating, a smoothing acceleration and inrush current decrease can be achieved by the series SCR trigger.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.3
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• pp.433-441
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• 2022

In general, in an emergency generator system for an electric facility including an induction motor load, an emergency power generation facility larger than the facility load capacity is built due to the initial starting current of the induction motor. In order to reduce this economic burden, various methods to reduce the inrush current of induction motors are applied to suppress the additional expansion of generators due to the reduction of power generation facilities and the increase in electrical facilities. Among these methods, when a system with a built-in soft start function of an induction motor using an inverter is built, it is the best way to reduce the inrush current of the induction motor to less than the rated current. However, in this case, the installation cost of the inverter to drive the induction motor increases. This paper proposes a soft start method of an induction motor by expanding the frequency and voltage control operation area of an emergency generator. In addition, proposed a speed calculation method based on power factor information, which is essential information for stable soft start of an induction motor, and a method for generating a speed command value of the governor for starting with maximum torque.

• Journal of Electrical Engineering and Technology
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• v.11 no.5
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• pp.1179-1189
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• 2016

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.2103-2105
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• 1998

Switched Reluctance Motor is simple structure which used Accel/Decel application field because of cheap cost and High efficiency. For driving this motor, it is essential to need position sensor and driving converter. so, many topology and sensor have been studied untill now. Asymmetric Bridge Converter which has been known for the best control and efficiency is used chopping to control current of motor coil according to changing of motor speed. But this is embossed as a fault because it come to bring switching loss due to rapid switching frequency. In this paper, I applied to Soft Switching Mode by Partial Resonant Method to compensate these fault and to show the usabilityness of low switching device.

• Journal of the Korean Society of Physical Medicine
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• v.3 no.2
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• pp.121-125
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• 2008

Purpose : The objective of this study was conducted to find out the treatment of joint problems. Methods : This is a literature study with books, seminar note and international course books. Results : Passive oscillation and distraction movement therapy is only joint mobilization and pain control. In the joint therapy need muscle strengthening, training of eccentrical control and neurophysiological therapy for joint mobility, stability, stability of mobility and skill. Conclusion : Joint therapy is not only joint mobility but also strengthening of soft tissue. Need the neurophysiological therapy those are use of ventromedial motor nucleus and dorsolateral motor nucleus, reciprocal inhibition, eccentrical muscle contraction training, proprioceptors and exteroceptor for structures and functional activities. For the pain control, reduce swelling, keeping GAGs and functional activities need direct and indirect therapy.