• Journal of Power Electronics
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• 제7권4호
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• pp.271-277
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• 2007

In this paper, an induction motor rotor fault diagnosis system using current signals, which are measured using the axis-transformation method is presented. Inverter-fed motor drives, unlike line-driven motor drives, have stator currents which are rich in harmonics and therefore fault diagnosis using stator current is not trivial. The current signals for rotor fault diagnosis need precise and high resolution information, which means the diagnosis system demands additional hardware such as a low pass filter, high resolution ADC, an encoder and additional hardware. Therefore, the proposed axis-transformation method is expected to contribute to a low cost fault diagnosis system in inverter-fed motor drives without the need for any additional hardware. In order to confirm the validity of the developed algorithms, various experiments for rotor faults are tested and the line current spectrum of each faulty situation, using the Park transformation, is compared with the results obtained from the FFT(Fast Fourier Transform).

• 전기학회논문지
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• 제63권4호
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• pp.575-582
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• 2014

In this paper, a simulation model for 7-phase BLDC motor drives for an Autonomous Underwater Vehicles (AUV) is proposed. A 7-phase BLDC motor is designed and the electrical characteristics are analyzed using FEA program and the power electronics drives for the 7-phase BLDC motor are theoretically analyzed and the actual implementation has been accomplished using Matlab Simulink. PI controller is used for verifying the validity of the proposed model and the informative results are described in detail.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.604-606
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• 1992

Many Industrial applications require high facultied and high efficiency motor drives. Recently, as such motor driving system, switched reluctance motor ( S R M ) drives are proposed. This paper describes the design features, drive circuits, and performance of 6/4 S R M for high efficiency variable speed drives. The main advantages of these motors lie In high efficiency, simple driving circuitry, and low manufacturing cost. The prototypes have been built and tested, showing satisfactory performance.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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• pp.400-403
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• 2001

In this paper, the classical Lyapunov synthesis method for designing controllers is extended to fuzzy logic. This control technique is then applied to the design of a novel tracking controller for reluctance motor drives. The main features of the method are small rule base, simplicity of construction, and low cost. The proposed controller has been simulated for a model case. In addition, its dynamic performances have been shown to be satisfactory. Capabilities of the proposed technique in controlling the highly nonlinear systems of reluctance motors with much simplicity are also verified.

• Journal of Power Electronics
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• 제5권2호
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• pp.166-172
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• 2005

The basic equations of a doubly-fed long-stator linear motor for a shuttle-based railway system are established. They show which degrees of freedom exist for controlling the motor. The ratio of stator and rotor current proves to be an important parameter in determining the design of motors, converters and mechanics.

• 로봇학회논문지
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• 제9권1호
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• pp.67-77
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• 2014

An electric motor is the one of the most important parts in robot systems, which mainly drives the wheel of mobile robots or the joint of manipulators. According to the requirement of motor performance, the controller type and parameters vary. For the wheel driving motors, a speed tracking controller is used, while a position tracking controller is required for the joint driving motors. Moreover, if the mechanical parameters are changed or a different motor is used, we might have to tune again the controller parameters. However, for the beginners who are not familiar about the controller design, it is hard to design pertinently. In this paper, we develop a nominal robust controller model for the velocity tracking of wheel driving motors and the position tracking of joint driving motors based on the disturbance observer (DOB) which can reject disturbances, modeling errors, and dynamic parameter variations, and propose the methodology for the determining the least control parameters. The proposed control system enables the beginners to easily construct a controller for the newly designed robot system. The purpose of this paper is not to develop a new controller theory, but to increase the user-friendliness. Finally, simulation and experimental verification have performed through the actual wheel and joint driving motors.

• 제어로봇시스템학회논문지
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• 제20권3호
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• pp.323-332
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• 2014

Stepper motor is widely used in positioning applications due to its durability and high torque to inertia ratio as well as low cost and ability to be easily controlled with open-loop. Due to increased resolution of position control and improved stability of motion control, microstepping has drawn attention in industry since it was introduced in 1970s. With the increase in computational power and decrease in cost of embedded processors in recent years, drives and control systems for stepper motors have become more sophisticate than ever. Thus, closed-loop control methods have been developed to improve the performance of the stepper motors. In this paper, we review not only basic principles of conventional control methods used for stepper motors but also that of microstepping control. In addition, we surveyed recent development in nonlinear control methods applied to stepper motors. The nonlinear control methods are presented in the view of Lyapunov stability. Nonlinear torque disturbance observer, sliding mode control, and nonlinear phase compensation are also presented.

• Journal of Power Electronics
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• 제6권4호
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• pp.315-321
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• 2006

Switched Reluctance Motors (SRM) have emerged as viable alternatives to other adjustable speed drives such as vector controlled induction motors (VCIM) and permanent magnet brush-less (PMBL) motors due to their simple construction, ease of control, low inertia and higher operating speeds. However, the indispensability of the rotor position sensor in an SRM for its successful operation increases its cost, apart from causing other problems like decreasing its reliability and inability to operate in adverse environmental conditions. In this paper, a new sensorless control scheme for the SRM is advocated. The required fundamental data is obtained by analyzing the SRM using the Finite Elements (FE) package MAXWELL. The drive is studied in both 'with sensor' and 'sensorless' modes and a comparison of the performances, in both cases, is presented for various operating conditions.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.549-555
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• 2003

The technology of machine condition monitoring is used effectively to detect the machine faults at an early stage using different machine quantities, such as current, voltage, temperature and vibration. Induction motors are most widely used to drive pumps, compressors and fans in industrial drives. This paper presents approach to data fusion using Dempster-Shafer theory because only one technique has uncertainty. So we can obtain advanced accuracy of the machine fault diagnosis. Vibration and current quantities are applied to diagnose three-phase induction motor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.588-590
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• 1994

This paper describes current controlled PWM technique of IPM synchronous motors for a wide variety of speed control applications. The IPM synchronous motors have a saliency, in which the q-axis inductance is larger than the d-axis inductance. As a consequence, there exists a reluctance torque component Thus when this component is added to the torque component produced by the stator currents and the air-gap flux, IPM motor drives are readily applicable where full torque Is required up to full or base speed. They are however limited in their ability to operate in the power limited regime where the available torque is reduced as the speed is increased above its base value. This paper reviews the operation of the IPMSM drives when they are constrained to be within the permissible envelope of maximum inverter voltage and current to produce the rated power and to provide this with the highest attainable rotor speed. The wide variety of speed control strategy is analyzed and the performance is investigated by the computer simulation using actual parameters of a drive system. Simulation results are given and discussed.