• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.9
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• pp.1103-1111
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• 1999

STACOM will be utilized to control substation voltage in the near future. Although STACOM shows good voltage regulation performance owing to its rapid and continuous response, it needs additional reactive power compensation device to keep control margin for emergency such as fault. ULTC transformer is one of good candidates. This paper presents a Kohonen Neural Network (KNN) based coordination control scheme of ULTC transformer and STACOM. In this paper, the objective function of the coordination control is minimization of both STACOM output and the number of switchings of ULTC transformer while maintaining substation voltage magnitude to the predefined constant value. This coordination, control is performed based on reactive load trend of the substation and KNN which offers optimal tap position in view of STACOM output minimization. The input variables of KNN are active and reactive power of the substation, current tap position, and current STACOM output. The KNN is trained by effective Iterative Condensed Nearest Neighbor (ICNN) rule. This coordination control applied to IEEE 14 bus system and shows satisfactory results.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.5
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• pp.482-488
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• 2009

Dancer system is typically used equipment for attenuation of tension disturbances. In industrial converting machines, a composite type of dancer system is applied which is mixture of active and passive dancer. It includes feedback position control loop of roll with pendulum dancer and its characteristics is different from passive and active one. In this paper, a mathematical model of the pendulum dancer was derived including PI position feedback controller and it was analyzed by using a pole-zero map and bode plot under various conditions. It was found out that velocity, length of span and inertia were associated with the performance of regulation. It was suggested that the length of upstream span should be greater than that of the downstream and the inertia should be smaller for improvement of the performance. The results can be used for design guidelines of the industrial dancer system.

• Proceedings of the KIEE Conference
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• 1998.07b
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• pp.684-686
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• 1998

This paper consider fuzzy control of a single-inverted pendulum attached to the tip end of a rotating arm driven by a direct driven motor. Control objectives stabilization of the pendulum at the upright position and regulation of the arm at an arbitrary specified position. Fuzzy control is an effective method to achieve multiple control objectives in control of nonlinear systems. In this paper, fuzzy logic control is proposed to obtain increased control performance and stability.

• KIEE International Transactions on Power Engineering
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• v.4A no.4
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• pp.207-213
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• 2004

In this paper, the on-line volt/var control algorithms of the Load Tap Changer (LTC) transformer and Shunt Capacitor (SC) are proposed for distribution volt/var compensation. In the existing volt/var control of the distribution substation, the feeder voltage and reactive power demand of the distribution are mainly controlled by the LTC transformer tap position and on/off operation of the Sc. It is very difficult to maintain volt/var at the distribution networks within the satisfactory levels due to the discrete operation characteristics of the LTC and SC. In addition, there is the limitation of the LTC and SC operation times, which affects their functional lifetimes. The proposed volt/var control algorithm determines an optimal tap position of the LTC and on/off status of the SC at a distribution substation with multiple connected feeders. The mathematical equations of the proposed method are introduced. A simple case study is performed to verify the effectiveness of the proposed method.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.2
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• pp.114-121
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• 2013

High efficiency operation is required for motors of vehicle to increase fuel efficiency due to the regulation of exhaust gas. This paper presents a control method of fuel pressure to increase fuel efficiency and a sensorless control method of BLDC motor to get higher efficiency than conventional brushed DC motor. Initial rotor position of BLDC motor is detected from current value that is occurred by test voltage pulse and rotor is accelerated by defined sequence to enter sensorless operation mode. The algorithm to control flow rate of fuel pump uses PI controller that is control motor speed to maintain the target fuel pressure commanded by ECU.

• Journal of Power Electronics
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• v.19 no.6
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• pp.1449-1457
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• 2019

This paper presents two voltage domain stacking topologies for powering integrated digital loads such as multiprocessors or 3D integrated circuits. Pairs of loads and capacitors are connected in series to form a stack of voltage domains. The voltage is balanced by switching the position of the capacitors in one case and the position of the loads in the other case. This method makes the voltage regulation robust to large differential load power consumption. The first configuration can be named the load stacking topology. The second configuration can be named the capacitor stacking topology. This paper aims at proposing and comparing these two topologies. Models of both topologies and a switching scheme are presented. The behavior, control scheme, losses and overall performance are analyzed and compared theoretically in simulation and experiments. Experimental results show that the capacitor stacking topology has better performance with a 30% voltage ripple reduction.

• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.382-385
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• 1999

In this paper, by means of Lyapunov second method, the stability of IPD control servo systems is analyzed in the time domain for the first time. Based on the results of the stability analysis, the design rule to select the gain of IPD control is suggested such that the maximum error of output to the nominal system is guaranteed for all uncertainty and load variations. An example of a position control of a brushless dc motor is given to prove the unusefulness of the gain design rule.

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.57-61
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• 1989

An adaptive control scheme is presented for uncertain systems whose uncertaintiy bounds are expressed as a linear combination of unknown functions of special form. Both the states and the parameter estimate errors of the closed-loop system are proven to be bounded. The regulation errors can be made sufficiently small by adjusting the design parameters. An application of the proposed method to the position control of a simple pendulum is given.

• Proceedings of the IEEK Conference
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• 2002.06d
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• pp.279-282
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• 2002

This Paper of use vision system, there is no DGPS's information, DGPS data value receives real time exactly without being influenced in surroundings environment because using vision system that is used in self-regulation traveling by car system. Therefore, conversion and DGPS of received in camera coordinate changing coordinate error correct and wish to grasp correctly position of vehicles.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.451-457
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• 2008

The aim of the sturdy is for the development of Bridge plate installing on floor for SETPA Sliver line V. SEPTA train have pocket sliding door which is similar with domestic trains. typically In the USA railway market, Portable type and standing type bridge plate used, easily hiding the bridge plate in stowed position and convenience operation, Bridge plate installed on floor is designed. relative regulation Like CFR APTA, and EN, UIC is reviewed and compared.