• 대한전기학회논문지:전력기술부문A
• /
• 제48권4호
• /
• pp.402-409
• /
• 1999

Variable structure control law is well known to be a robust control algorithm and evolution strategy is used as an effective search algorithm in optimization problems. In this paper, we propose a variable structure controller with time-varying switching surface. We calculate the maximum value of seitching surface gradient that is of the 3rd order polynomial form. Evolution strategy is used to optimize the parameters of the switching surface gradient. Finally, the proposed method is applied to position tracking control for BLDC motor. Experimental results show that the proposed method is more useful than the conventional variable structure controller.

• 한국자동차공학회논문집
• /
• 제6권3호
• /
• pp.106-114
• /
• 1998

Cogging torque is often a principal source of vibration and control difficulty in permanent magnet motors, especially at low speeds and loads. For example, reduction of cogging torque is an important specification for DC motors used for electric power stee- ring. This paper examines two motor design techniques, stator tooth notching and rotor pole skewing with magnet pole shaping, for reduction of cogging torque, and the effect of each method on the airgap flux, and the use of the Maxwell stress method and Fourier decomposition to calculate the periodic cogging torque. The analyses show that the cogging torque can be nearly eliminated by the suggested designs, with minimal scacrifice of output torque.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2008년도 제39회 하계학술대회
• /
• pp.637-638
• /
• 2008

최근 하이브리드 전기자동차의 관심이 높아짐에 따라 전기적 신호의 연결로 구동 시스템을 구성하는 X-by-wire기술 연구가 활발하게 이루어지고, 있다. 그 중 Drive시스템을 관장하는 Throttle-by-Wire 기술의 일환으로 ETC(Electronic Throttle Control)장치에 대한 연구가 진해되고 있으며, 일부 제품이 출시되고 있다. ETC 구성요소 중 가장 핵심인 모터 설계를 위해 본 논문에서는 우수한 성능을 가지는 BLDC 모터를 선택하고, 기초 설계를 통해 그 형상을 설계하였으며, 보다 더 높은 효율과 출력 토크를 얻기 위해 회전자 영구자석의 재질과 형상을 변화시키며 효율과 출력 토크에 미치는 영향을 살펴보았다.

• 전력전자학회논문지
• /
• 제11권2호
• /
• pp.113-119
• /
• 2006

본 논문은 CTDP 기법을 이용한 다양한 역기전력을 갖는 BLDCM(Brushless DC Motor)의 토크특성에 대하여 연구하였다. 상전환 및 상전환 시점에 의한 토크맥동을 개선하기 위한 CDTP 기법을 제안하였다. 이를 위하여 Hague의 해석방법에 따른 실제 역기전력을 갖는 BLDCM의 제어에 적용하였으며 이때 실제 역기전력은 착자의 가장자리 지수와 평탄구간에 의해 발생된다. 이의 검증을 위하여 시뮬레이션 및 실험을 통하여 제안한 방식을 이용한 토크맥동 저감방법의 타당성을 살펴보았다.

• 한국정밀공학회지
• /
• 제30권9호
• /
• pp.951-959
• /
• 2013

In order to improve the speed performance of the direct drive mechanical systems, a comprehensive analysis of the velocity ripples of blushless DC motors should be required. Every motor has a certain level of torque ripples when it generates power, and the generated torque ripple also makes the velocity ripples in the final output stage in speed control system. In this paper, a novel algorithm for reducing velocity ripples is proposed based on the modeling of torque ripples for BLDC motors. Various algorithms have been made for torque ripples, but usually they should be installed inside the amplifier logic, result in the difficulties of flexibility for various kinds of torque ripples. The proposed algorithm was developed for being ported in the controller not the amplifier, and it has the capability of the automatic compensation adjustment. The performance of the proposed algorithm was verified by effective simulations and experiments.

• Journal of Electrical Engineering and Technology
• /
• 제12권1호
• /
• pp.72-77
• /
• 2017

This paper proposes the explicit tuning rule of multi-loop PID controller for brushless direct current motors to predict the system behaviors in time and frequency domains, using properties of the convex combination method. The convex set of the proposed controllers formulates the envelope to satisfy the performances in time and frequency domains. The final control parameters are determined by solving the convex optimization problem subject to the constraints which are represented as convex set of time domain performances. The effectiveness of the proposed control method is shown in the numerical simulation, in which controller tuning algorithm and dynamics of brushless DC motor are well taken into account.

• Transactions on Control, Automation and Systems Engineering
• /
• 제2권3호
• /
• pp.149-156
• /
• 2000

Time delay observer (TDO), thanks to the time delay control (TDC) concept, requires little knowledge of a plant model, and hence is easy to design, robust to parameter variation and computationally efficient, yet can reconstruct states rather reliable for nonlinear plant. In this paper, we propose an improved version of TDO that solves two problems inherent in TDO as follows: TDO displays large reconstruction errors due to low-frequency uncertainty and has some restrictions on selecting its gains. By introducing a low pass filter and a state associated with it, we obtain an enhanced time delay observer (ETDO). This observer turns out to have smaller reconstruction errors than those of TDO and not to have any restriction on selecting its gains, thereby solving the problems. Through performance comparison by transfer function and simulation, we validate the analysis results of two observers (TDO and ETDO) and evaluate the performances. Finally, through experiments on BLDC motor system, the analysis results are clearly conformed.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1999년도 하계학술대회 논문집 B
• /
• pp.573-575
• /
• 1999

Brushless DC motor which has the characteristics of high efficiency and high torque, can be controlled speed by the encoder or resolver. But these sensors cost highly and have the problem that they increases the size. This paper proposes a speed control by Hall-Sensor. which is small and cheap. But this sensor has a problem of low resolution. To solve the problem this paper proposes speed control by using a least square algorithm.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2002년도 추계학술대회 논문집
• /
• pp.361-365
• /
• 2002

In this paper, a magnetic suspension system with inductive sensors fur a high vacuum turbomolecular pump(TMP) is discussed. The performance of designed inductive position sensor is evaluated by static and dynamic test, and the test results show sensitivity of about 6,000 V/m and dynamic bandwidth of 750 ㎐. The protype of magnetic suspension system is designed and constructed with 5-axis magnetic bearing, inductive sensor and BLDC internal motor. With DSP based digital PID control system, the prototype is examined its high damping ratio and stable operation up to 20,000 rpm of rotation.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2001년도 전력전자학술대회 논문집
• /
• pp.167-171
• /
• 2001

In PCB assembling line, it needs SMD mounter. In this paper, the feeder of the SMD mounter, which carry component to the mounter is designed. Up to now, mechanical air feeder is mainly used. But in these days, it is developed to the electrical feeder with network. There are many kind of feeders with various control technique. In this paper, the feeder with BLDC motor and LON chip is designed and implemented. Then the experimental results are presented.