• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.1
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• pp.58-66
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• 2009

In this paper, vector control to applied disturbance offset feedforward loop control for changing disturbances with various mechanical parameter is suggested. The proposed system estimate load torque based on induction motor torque using minimum diemension state observer. Because speed controller using state observer is used on condition of feedforward loop fur a torque, the robust speed control system realized. In this study, the proposed paper does to heighten reliability of system by presuming and use the speed by voltage and current that is detected without speed sensor. To prove the propriety of this paper, the various simulation carried out adequacy using a Matlab Simulink, and at the same time real system is made, using a ADMC300 digital signal processor, so it is proved. As the experimental result of embodying the system, the robust system is realized.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.232-232
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• 2000

switched reluctance motors and drives are increasingly used in industrial applications due to their robust mechanical structure, low inertia and reduction in the rotor losses. As the motor speed increase turn on angle must be advanced to build up phase current. When C-dump converter is applied to switched reluctance motor, the capacitance of dump C has to have proper value. In this paper advance angle for a switched reluctance motor and capacitance of dump C are investigated. Then proper advance angle and the capacitance of dump-C are propose for the industrial low voltage SR motor.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.373-375
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• 2004

The SRM is more robust and lower cost than other type motors. The inverter for SRM cannot have shoot through fault, since a phase winding of SRM is independent of other phase windings. The SRM has high starting torque and high power density. But it has torque ripples due to nonlinear magnetic characteristics. Therefore, SRM has highly non-linear torque producing characteristics. Because fuzzy logic is a flexible and general-purposed method for implementing non-linear dynamic functions, it is effective for the control of high current SRM. We design the fuzzy controller and demonstrate the fuzzy control system by MATLAB.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.230-230
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• 2000

This paper describes a model reference adaptive system(MRAS) for speed control of vector-controlled induction motor without a speed sensor. The proposed approach is based on observing the instantaneous torque. The real torque is calculated by sensing stator current and estimated torque is calculated by stator current that is calculated by using estimated rotor speed. The speed estimation error is linearly proportional to error between real torque and estimated torque. The proposed feedback loop has linear component. Furthermore proposed method is robust to parameters variation. The effectiveness is verified by equation and simulation

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.1922-1924
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• 1998

In this paper, the robust vector control method of Induction Motor for the purpose of improving the system performance deterioration caused by parameter variations is proposed. The full order state observer estimates the stator current and the rotor flux by using the state prediction of state variables. And, the motor speed is estimated without speed sensor using the full order state observer. Also, the parameter variation is compensate by the Sliding Observer. By using this method, speed sensorless control and current contol with no affection of the parameter variation can be obtained simultaneously.

• Proceedings of the KIEE Conference
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• 1995.07a
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• pp.385-387
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• 1995

The current mode controlled DC/DC converter using fuzzy logic controller is proposed. With the proposed control method, the robust and safty guaranteed operation are achieved. For comparison with conventional controller, the PI controller is selected. By the computer simulation results, the validities of the proposed control method will be shown.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.5
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• pp.923-928
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• 2009

The performance analysis and robust control of the interior permanent magnet synchronous motor(IPMSM) greatly depend on accurate value of its parameters. To achieve the high performance of torque control, it is necessary to consider exact inductance values because the inductances are nonlinear parameters of operating the IPMSM. Therefore many different methods have been performed for analysis of the methodology for the exact measurement of synchronous inductances. None of them is considered standard, and accuracy levels of all these methods are also not consistent. Among these experimental methods, the DC current decay test and the vector current control test are ideal for a laboratory environment. In this paper, these two test methods are compared by applying inductances to the IPMSM. The paper analyzes the measured inductances of the two methods and their differences with inductances obtained from the finite element method(FEM).

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.10
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• pp.1066-1074
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• 1990

In this paper, we attempt to control induction motors with high power efficiency as well as high dynamic performance by utilizing the recently developed theories : singular perturbation technique and noninteracting feedback control. Our controller consists of three subcontrollers` a saturation current controller, a decoupling controller, and a well-known flux simulator. The decoupling controller decouples rotor speed (or motor torque) and rotor flux linearly. Our controller does not need the rotor resistance that varies widely with the machine temperature. To illuminate the practical significance of our results, we present simulation and experimental results as well as mathematical performance analysis.

• Proceedings of the KIPE Conference
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• 2007.11a
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• pp.103-107
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• 2007

In doubly fed induction generators (DFIGs), control of rotor currents allows for adjustable speed operation, active, and reactive power control. This paper presents a DFIG control strategy that enhances the active and reactive power control with controllers that can compensate for the errors caused by current measurement path in the DFIG system. The errors can be divided into two categories: offset and scaling errors. These can induce the speed, active, and reactive power pulsations, which are one and two times the fundamental slip frequency in the DFIG. And these undesirable ripples can do the DFIG harm. In this paper, a new compensation algorithm is proposed. Therefore, the proposed algorithm has several advantages: to implement is easy; it require less computation time; it is robust with regard to the variation of the induction generator parameters. In this paper, a new algorithm is introduced by using the integral of phase currents to measure the current ripples of rotor-side converterin the DFIG system. The experiment results are shown the effectiveness of the proposed method.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.4B no.2
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• pp.59-64
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• 2004

Study of an accurate and robust braking control method is required as a technical improvement to the servo system. In particular, the braker exhibiting constant braking performance under speed variation conditions of the prime mover needs to be investigated. In this paper, the braking torque of the eddy current braker between the electromagnet stator and rotating disk is analyzed. The torque-speed characteristics and accurate disk construction are represented. From the computer simulation results, it was found that eddy current braking torque is linear or approximately constant over the desired speed range depending on the rotor material, disk construction, pole number and pole displacement of the stator. These relations are confirmed by experimental results.