• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2004년도 전력전자학술대회 논문집(1)
• /
• pp.274-278
• /
• 2004

This paper presents a strategy to drive built in-type spindle induction motor which is used as CNC (Computer Numerical Control) in the industrial world. The direct vector control which is robust to the changed machine parameters in the high speed range is used in this motor control method. And electrical model of induction motor presents the basic idea based on observer structure, which is composed of voltage model and current model. But the former has the defects in low speed range, the latter has the defects of sensitivity to motor parameter. Thus Gopinath model flux estimator which is the closed loop flux observer based on two models for the rotor flut estimation is used in this paper. Moreover this paper presents to drive the spindle motor in the high speed range by using the flux weakening control.

• 전력전자학회논문지
• /
• 제3권1호
• /
• pp.23-35
• /
• 1998

영구자석 동기전동기의 제어에 있어서 토오크 맥동은 전동기 제어성능 결정에 큰 요인으로 작용한다. 본 논문에서는 이러한 토오크 맥동을 효과적으로 저감하기 위한 새로운 토오크 추정 및 제어기법에 대해서 다룬다. 제안된 기법에서는 모델 기준 적응시스템(Model reference adaptive system ; MRAS) 기법을 이용하여 순시 토오크를 추정하고 적본형 가변구 조제어(Integral variable structure control ; IVSC)를 이용하여 추정된 토오크를 제어한다. DSP를이용하여 고 토오크 영구자석 동기전동기 제어시스템을 구성하고 실험을 수행하였으며 그 결과 제안된 제어기법이 우수한 토오크 맥동 저감효과를 가짐을 입증하였다.

• Journal of Power Electronics
• /
• 제9권3호
• /
• pp.438-446
• /
• 2009

The performance of direct torque controlled (DTC) interior permanent magnet (IPM) machines is poor at low speeds due to a few reasons, namely limited accuracy of stator voltage acquisition and the presence of offset and drift components in the acquired signals. Due to factors such as forward voltage drop across switching devices in the three phase inverter and dead-time of the devices, the voltage across the machine terminals differ from the reference voltage vector used to estimate stator flux and electromagnetic torque. This can lead to instability of the IPM drive during low speed operation. Compensation schemes for forward voltage drops and dead-time are proposed and implemented in real-time control, resulting in improved performance of the space vector modulated DTC IPM drive, especially at low speeds. No additional hardware is required for these compensators.

• 전자공학회논문지SC
• /
• 제40권3호
• /
• pp.199-207
• /
• 2003

종래 직접 퍼지제어기에서는 누적 오차의 발생과 제어입력의 누적으로 인한 과도응답의 성능을 악화시킬 수 있으며 이러한 단점의 보완은 제어입력만으로 결정하기 어렵다. 본 논문에서는 이러한 문제점을 해결하기위해 과도상태에서 나타나는 오버슈트와 상승시간을 고려하기 위해 퍼지제어기를 이용한 재설정 변화분을 설정하며 이를 직접 퍼지제어기에 추가하여 병렬형태로 구성된 새로운 퍼지제어기를 구성한다. 본 논문에서 제시한 새로운 퍼지제어기를 IPMSM 드라이브에 적용하여 새로운 퍼지제어기가 직접 퍼지제어기와 비교하여 응답성능이 우수함을 제시하고 그 타당성을 입증한다.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2013년도 춘계학술대회 논문집
• /
• pp.1353-1354
• /
• 2013

• 조명전기설비학회논문지
• /
• 제23권2호
• /
• pp.138-147
• /
• 2009

본 논문에서는 5상 농형유도전동기(Five-phase squirrel-cage induction motor)의 수정된 직접 토크제어(Direct torque control, DTC) 시스템을 제안한다. 5상 유도전동기 구동은 추가적인 자유도로 인하여 개선된 특성이 얻어짐과 동시에 일반적인 3상 유도전동기에 비해 토크의 맥동이 감소하며, 신뢰성 증가와 같은 장점을 가진다. 5상 유도전동기의 직접 토크제어는 인버터 구동시스템이 기존의 3상 인버터가 8개의 공간전압 벡터를 가지고 있는 것에 비해서 32개의 공간전압 벡터를 제공하기 때문에 여러 가지 장점이 있다. 그러나 5상 전동기의 경우는 제3공간 고조파 성분으로 인하여 구조적인 단점을 가지고 있어 고조파 성분의 전류제어가 요구된다. 따라서 이 논문에서는 5상 유도전동기의 특성을 개선하기 위하여 제3고조파 전류성분을 제어할 수 있는 수정된 직접 토크제어 시스템을 제시한다. 전통적인 5상 유도전동기의 직접 토크제어와 제안된 직접 토크제어 시스템의 운전특성을 검증하기 위하여, 디지털 제어기로 32[bit] 고정소수점 DSP인 TMS320F2812를 사용하여 2.2[kW] 5상 유도전동기의 속도제어 시스템을 구성하여 동특성을 관찰한 결과 우수한 특성이 얻어짐을 확인하였다.

• 조명전기설비학회논문지
• /
• 제22권3호
• /
• pp.59-65
• /
• 2008

High-speed electrical motor has been studied for several applications, i.e. for direct-drive systems of centrifugal compressors and turbo blowers. This paper deals with a design consideration of electromagnetic, mechanical and thermal limits of high-speed induction motor for turbo blower. Basic design concept of high-speed motor was proposed. As the motor is to be operated at high speed, the losses are quite different from conventional low-speed machines. Especially, the increases of rotor eddy current and friction losses could lead to an overheated motor. So, we suggested a special cooling system to reduce temperature rise. And, based upon this design concept, the prototype induction motor(37[kW], 45,000[rpm]) for high-speed turbo blower was designed and 2-D electromagnetic field analysis was implemented. Finally, criteria to evaluate the characteristics of high-speed induction motor have been proposed and tested.

• Journal of Power Electronics
• /
• 제9권5호
• /
• pp.679-690
• /
• 2009

The paper presents a new photovoltaic inverter for stand-alone induction motor application. The proposed system is composed of two stages. First stage is for the photovoltaic dc power feeding and second stage is dedicated to the motor-inverter subsystem and control technique. A direct torque control (DTC) with a novel switching strategy for motor torque ripple minimization is introduced. The novel DTC strategy is based on selecting a suitable voltage vector group for motor torque ripple minimization. A three-level voltage source inverter (VSI) is used instead of a two level inverter because the first has more available vectors and lower ripples in the output current and flux than the second, thus it has lower torque ripples. The photovoltaic array and battery bank are sized and the configuration is indicated based on sun-hour methodology. Simulation results show a comparison between three systems; two level VSI with conventional DTC strategy, three level VSI with conventional DTC, and the proposed system that has a novel DTC switching strategy applied to three level VSI. The results show that the proposed system has lower ripples in the current, flux and torque of the motor.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2007년도 하계학술대회 논문집
• /
• pp.321-324
• /
• 2007

The actuators of anti-vibration system(AVS) can be separated into several types: piezoelectric actuators, pneumatic springs, cylinders, rotating motor and linear motor. The last one has some advantages, such as low noise, low vibration, simpler configuration and possibility of direct drive. The voice coil motor(VCM) is one type of linear motor, originally used in speaker system. VCM actuators are usually used in occasions that rapid and controlled motion of devices are required. In this paper, a controller which satisfies system specification(e.g. current controller bandwidth) within whole operation range is designed. For that objective, parameters as position were initially obtained with 3D FEM analysis and motor modeling was performed. A current controller in 2-axis VCM drive system was designed and then performance of the proposed controller was verified with simulation using Simplorer and an experimental result.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2010년도 하계학술대회 논문집
• /
• pp.585-586
• /
• 2010

An induction motor operated with a conventional direct self controller(DSC) shows a sluggish response during startup and under changes of torque command. Fuzzy logic controller(FLC) is used in conjunction with DSC to minimize these problems. A FLC chooses the switching states based on a set of fuzzy variables. Flux position, error in flux magnitude and error in torque are used as fuzzy state variables. Fuzzy rules are determinated by observing the vector diagram of flux and currents. This paper proposes hybrid FLC for direct torque control(DTC) of induction motor drives. This controller is controlled speed using hybrid FLC. The performance of the proposed induction motor drive with hybrid FLC is verified by analysis results at various operation conditions.