• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.1055-1059
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• 1992

Instantaneous Voltage Control of inverter for uninterruptible power supply(UPS) is presented. In order to improve the transient response, the authors propose a control scheme based on a double regulation loop with sinusoidal hysteresis band. And also, using 8097 single chip microprocessor, software synchronization and static switch control scheme is impremented with minimal hard ware structure.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.68.5-68
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• 2002

For the performance test of rechargeable electric tools, it is necessary to test under the same condition as the actual operation condition. They are necessary to control the load torque and to acquire the test data with a computer, and it should be convenient to fix the tool on the test equipment for rechargeable electric tools. It consists of torque loading parts, sensing parts and control software. Two hysteresis brakes, connected serially with flexible coupling, were applied to control the load for the test. The sensing part consists of a torque sensor, a rpm detector and a power analyzer. The torque and the rpm were measured in order to calculate the output of the rechargeable electric...

• Proceedings of the KIPE Conference
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• 2003.07b
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• pp.729-733
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• 2003

This paper proposed a novel current control strategy on active power filters using p-q-r instantaneous power theory which can compensate the line current harmonics and the neutral line current in unbalanced and/or distorted source conditions in three-phase four-wire systems. The proposed current control method is based on a sinusoidal PWM for fully-digital implementation which was compared with a hysteresis PWM. Simulation results showed good performance of the proposed current control strategy on shunt type APFs.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.12
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• pp.862-871
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• 1988

In this paper, a vector control system of current controlled PWM inverter-induction motor drive is proposed for quick response control. As the instantaneous value of the stator current must be controlled to accomplish the superior vector control characteristic, the current controlled PWM inverter with hysteresis controller is adopted. Complex vector rotation and calculation are handled with microprocessor software. The superior characterictic of the proposed system is verified with digital simulation and experiment.

• 유공압시스템학회:학술대회논문집
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• 2010.06a
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• pp.18-24
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• 2010

Because of the increasing demand on the high precision and high response of a machinery, electronic control valves are widely adopted at various application fields. This paper studies on the static characteristic of a first-stage proportional pressure control valve. At first an experimental apparatus including hyd. pump variable speed inverter, pressure and data aquisition system was setted up with the experimental apparatus, various tests such as P-Q-W test, hyd, pump, dynamic, static, frequency response test of the proportional valve was carride out and the results are discussed.

• Proceedings of the KIEE Conference
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• 1999.07a
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• pp.12-14
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• 1999

Recently, the electromagnetic proportional valve has been widely used in order to control pressure and flow in such systems as NC machine and automatic facility. The linear electromagnetic solenoid used for proportional control valve ought to have hysteresis characteristic because of control the thrust force proportionably by input current. Therefore, in this study, we analysis the thrust force characteristics and established design for practical use, which allows Linear Pulse Motor(LPM) to be used as a driving system for electromagnetic proportional control valves.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.1025-1028
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• 1993

In this paper, an intelligent control scheme with multi-stage fuzzy inference is developed for a myoelectric prosthesis to achieve natural control with tactile feedback based on fuzzy control strategies. Strain gauges and a potentiometer are added to the prosthesis for tactile feedback with a PWM motor driver developed to save the battery power. According to the multi-stage fuzzy inference, the prosthesis can determine the stiffness of the object and hold an object without injuring it, meanwhile, the hysteresis phenomenon is an 80196KC single-chip microcontroller to replace the original controller.

• Journal of Power Electronics
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• v.18 no.6
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• pp.1634-1641
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• 2018

This study focuses on a high-performance direct active and reactive power controller design that is successfully applicable to three-phase pulse width modulation (PWM) AC/DC converters used in renewable distributed energy generation systems. The proposed controller can overcome the sluggish transient dynamic response of conventional controllers to rapid power command changes. Desired active and reactive powers can be thoroughly obtained at the end of each PWM period through a deadbeat solution. The proposed controller achieves an exact nonlinear cross-coupling decoupling of system power without using a predefined switching table or bang/bang hysteresis control. A graphical and analytical analysis that naturally leads to a control voltage vector selection is provided to confirm the finding. The proposed control strategy is evaluated on a 3 kW PWM AC/DC converter in the simulation and experiment.

• Journal of Drive and Control
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• v.10 no.4
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• pp.22-28
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• 2013

Mechanical and electrical properties of a DDV(Direct Drive servo Valve) with electric feedback are analysed via reverse analysis technique in this work. The DDV is disassembled and mechanical parameters, such as spool mass, spring stiffness and port size are identified. The servo amplifier, which is built in the valve, is reversely analysed and the control scheme and gains for several control actions are also identified. The electrical feedback for spool displacement improves much better the valve performance, such as hysteresis and dynamic bandwidth frequency, than an ordinary mechanical feedback valve. Integrating control action with very large gain was adopted in the valve amplifier, and it seemed to give high performance.

• Transactions on Electrical and Electronic Materials
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• v.14 no.1
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• pp.36-38
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• 2013

Eight sample panels using an indium tin oxide(ITO)-coated glass substrate were fabricated, with barrier ribs formed of 55 ${\mu}m$ height and 10 ${\mu}m$ width. The upper and lower substrates were designed with the same panel condition, so a cell gap of 110 ${\mu}m$ was obtained. The charged particles in a cell consisted of $TiO_2$ (for white color) or carbon black (black color), negative or positive charge control agents, and a polymer. The average diameter of the two types of particles was commonly 10 ${\mu}m$, and their q/m value was -4.5 ${\mu}C/g$ and +4.5 ${\mu}C/g$, respectively. The electrically opposite particles mixed by an agitator were loaded into their cells by a simple particle-loading method. The discharging process proceeded at a humidity of 80% and a temperature of $30^{\circ}C$. Reflectivity was measured depending on discharging time, and a hysteresis curve by bias voltage obtained for comparison between the neutralized and non-neutralized panel, in which the superior optical property of the neutralized panel was ascertained.