• 조명전기설비학회논문지
• /
• 제12권1호
• /
• pp.26-34
• /
• 1998

본 연구에서는 복권형 하이브리드 스테핑 전동기의 Lead Angle에 따른 순시 상전류값의 변화를 보이고 이를 실험적으로 확인하였다. Lead Angle에 따른 순시 상전류값의 변화는 상권선이 여기된 시점에서의 회전자 위치에 대한 정보를 제공한다. 따라서 복권형 하이브리드 스테핑 전동기의 폐루프 운전을 위한 회전자 위치검출 방법으로서 전동기의 순시 상전류를 이용할 수 있음을 보였다. 복권형 하이브리드 스테핑 전동기의 모델링을 통해 Lead Angle 함수로 주어지는 순시 상전류 식을 제시하였으며, 컴퓨터 시뮬레이션을 통해 순시 상전류와 회전자 자극위치와의 관계를 도시하고 분석하였고, 상전압 인가후 $\pi/2$ 시점에서의 순시 상전류값을 측정하여 회전자 자극위치 정보를 얻을 수 있음을 실험적으로 확인하였다.

• 제어로봇시스템학회논문지
• /
• 제2권4호
• /
• pp.318-323
• /
• 1996

The speed of SR(Switched Reluctance) motor can be controlled by switching angle. However, since the relation between speed and switching is nonlinear, it is difficult for simple adjustment schemes to achieve the desired performances. In this paper, an error.feedback nonlinear compensator with robustness is proposed for improving the performances of the switching angle controlled SR motor. The proposed controller consists of integral type control and relay type control. The integral type controller which operates regulation, is derived by the steady.state I/O(input/output) map and the relay type controller which works tracking, is designed by Lyapunov stability theory. The validities of the proposed controller are confirmed with the experimental results.

• 전기학회논문지
• /
• 제63권9호
• /
• pp.1245-1247
• /
• 2014

This paper presents a robust position tracking controller for motor-driven flexible joint manipulators using only the motor angle measurement. The control problem is not easy because the link position is hard to estimate in the presence of parameter uncertainties. The proposed controller consists of a feedback linearization controller (FLC) and two proportional-integral observers (PIOs) that estimate both system states including the link position and an equivalent disturbance for compensating the parameter uncertainties. Comparative computer simulations are conducted to demonstrate the effectiveness of the proposed control algorithm.

• 한국정밀공학회지
• /
• 제17권1호
• /
• pp.101-109
• /
• 2000

Mutual torque ripple in a brushless DC motor is the main source of acoustic noise, especially fur motor operation with high speed and torque. This paper presents a method to obtain mutual torque ripple to identify acoustic noise source. Mutual torque ripple can be determined by analyzing phase current shape and magnetic circuit with different lead angles. Current shape is determined by state space model of voltage equation with the use of inductance calculated by FEM, and confirmed by experimental results. Mutual torque ripple is also determined by FEM analysis for the calculated current shape. Acoustic noise experiment reveals that mutual torque ripple with different lead angle is one of the main sources for noise generation in a brushless DC motor.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
• /
• 제52권2호
• /
• pp.53-60
• /
• 2003

This paper deals with steady-state analysis of a single-phase line-start permanent magnet synchronous motor. In order to analyze the steady-state characteristics, the asymmetric single-phase line-start synchronous motor is converted to the symmetric two-phase synchronous motor, that is, the asymmetric magnetic field is separated from the positive and the negative symmetric components using symmetrical-component theory. The analysis method of the synchronous motor on the d-q axis coordinates is used for the positive component and the equivalent circuit of the induction motor is applied for the negative component analysis. Moreover, d-q axis inductance considering current phase angle is applied to positive component analysis for precise characteristic analysis. In order to validate the proposed analysis method, the analysis results are compared with the experimental results.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2005년도 춘계학술대회 논문집
• /
• pp.781-784
• /
• 2005

The feed drive inclination significantly influences product quality, machine tool accuracy and life time. However, the accurate measurement of the inclination needs the skilled engineers and the accurate leveling instruments such as spirits or electric levels. In this study a novel methodology for the estimation of inclination angle of machine tool feed drive is proposed. The proposed methodology utilizes the motor current signals and a new mathematical model of machine tool feed drive considering inclination. The experiment results showed that the proposed method successfully estimates the inclination angle, as well as newly proposed model also enhances the accuracy of the machine tool feed drive model by introducing the inclination effects.

• 산업기술연구
• /
• 제18권
• /
• pp.149-155
• /
• 1998

This paper describes a reference flux angle selection for a vector control in the parallel operation system that consists of a inverter and several induction motors. In particular, this paper suggests which flux angle of motors prefers for the vector control in the train drive system that diameters of wheels are different. Through simulation for a 210[kW] induction motor drive system, it is clear that the vector control by using of the flux angle of a motor having a minimum wheel diameter leads to a minimum torque difference. However, it requires too many current sensors. So, it is shown that the vector control by a average flux angle of motors is preferable.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1995년도 하계학술대회 논문집 A
• /
• pp.321-324
• /
• 1995

Switched reluctance motors and drives are increasingly used in high speed applications due to their robust mechanical structures, low inertia, and reduction in the rotor losses. The turn-on angle has to be advanced as the motor speed increases, but it may cause the starting problem in some rotor positions. In this paper, the characteristics of the maximum speed and input voltage with the advance angle at high speeds is investigated. To overcome the starting problem and reduce the torque ripple, conduction overlapping is added in adjacent phases. The effectiveness of conduction overlapping is verified through the simulation and experiments.

• 전력전자학회논문지
• /
• 제24권2호
• /
• pp.127-133
• /
• 2019

This paper proposes a restarting method for extended electromotive force (EEMF)-based sensorless permanent magnet synchronous motor (PMSM) drive systems. The sensorless PMSM drive systems generally estimate the rotor speed and angle based on EEMF. However, if the inverter is stopped while the PMSM is rotating, the initial rotor speed and angle are required for restart. Therefore, the proposed restarting method estimates the initial rotor speed and angle using the short-circuit current generated by applying zero voltage vector from the inverter. The validity of the proposed method is verified by simulation and experimental results.

• 한국정밀공학회지
• /
• 제31권2호
• /
• pp.113-117
• /
• 2014

Laser Assisted Machining (LAM) was often used in process of difficulty-to-cut materials. In previous study, Laser assisted machining was a straight path processing using 1-axis manipulator in laser module. But 1-axis manipulator in laser module was able to process only straight path. So, in this study, laser module in laser assisted machining equipped to 2-axis manipulator. 2-axis manipulator has two motors. First motor is machining direction motor and second motor is Vertical Motor. Machining direction motor rotates in the direction of machining and vertical motor rotates vertical direction in the direction of machining. Machining path of laser assisted machining was considered diagonal path and curved path of laser heat source. This study calculated the 2-axis manipulator's rotation angle in diagonal path and curved path.