• 전력전자학회논문지
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• 제7권5호
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• pp.427-436
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• 2002

본 논문은 직접토크제어(Direct torque control, DTC)를 사용한 릴럭턴스 동기전동기(Reluctance synchronous motor, RSM)의 위치센서 없는 모션제어 시스템을 제안한다. 고성능 효율제어를 수행하는데 있어서 DTC를 이용한 릴럭턴스 전동기 드라이브는 고정자 쇄교자속의 포화와 부하전류에 따라 비선형적으로 변하는 인덕턴스로 인해 여러 가지 문제점들이 발생한다. 이러한 이유로 본 논문에서는 정확한 고정자 쇄교자속과 토크를 계산하기 위해서 자속관측기의 $L_d\;와\; L_q$값을 회전자 위치와 고정자 전류에 대해 보상하였으며, 빠른 토크 응답특성과 최적 효율특성을 얻기 위해서 기준자속을 부하에 따라 계산하였다. 제안된 알고리즘의 정당성을 확인하기 위해서 1.0[kW] 릴럭턴스 동기 전동기를 사용하여 $\pm$20[rpm]과 $\pm$1500[rpm]에서 실험을 수행하였고, 실험을 수행한 결과 저속영역과 고속영역 모두 우수한 동특성과 향상된 효율을 얻을 수 있었다.

• 전력전자학회논문지
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• 제7권6호
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• pp.509-516
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• 2002

본 논문에서는 신경회로망을 이용한 스위치드 릴럭턴스 전동기(Switched Reluctance Motor, SRM)의 간편한 순시토크 추정기법과 스위칭 각 제어에 관해 연구하였다. 간단한 구조와 높은 효율 등의 많은 장점을 가지고 있는 SRM은 부하토크와 회전속도에 따라 운전특성이 달라지므로 최적운전을 위해서는 스위칭 각 제어가 필수적이다. 이러한 스위칭 각은 고정자 및 회전자 극호각, 토크 및 속도 능의 여러 변수들에 따라 달라지기 때문에 적정 스위칭 시점을 결정하는데 있어서 어려움이 있다. 따라서 본 논문에서는 부하토크 및 회전속도에 따라 효율이 가장 높은 적정 스위칭 각을 실험을 통해 선정한 후 신경회로망(Neural Network, NN)을 이용하여 전동기 제어에 적용하는 방안에 관해 고찰하였다. 또한 스위칭 각 제어에 있어서 필수적인 순시토크의 추정에 있어서도 신경회로망을 이용하여 인덕턴스의 비선형적인 특성이 고려되도록 하였다. 구현된 스위칭 각 제어기를 실제 시스템에 적용하였으며, 고효율 측면에서 선정된 스위칭 각 제어기의 동특성을 확인함으로써 스위칭 각 제어기의 적합성을 검증하였다.

• Journal of Power Electronics
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• 제9권6호
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• pp.911-918
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• 2009

This paper presents a new sensorless control method for single-phase switched reluctance motors using induced electromotive force (EMF) due to the residual flux both on the stator and the rotor during phase commutation. The induced EMF falls to zero when the rotor pole moves away from the overlap with the stator pole. By detecting this instant, the speed and position of the rotor can be simply estimated. This method is very simple to implement and it is insensitive to variations in the system parameters as it does not require any stored magnetic data or offline inductance measurements but requires only measurements of the terminal voltage and a simple analog circuit. The proposed method is implemented on a 6/6 single-phase switched reluctance motor. However, it can also be implemented on a multiphase SRM regardless of the size, operation speed and switching mode of the motor hence making the proposed method viable to many applications. Simulation and experimental verification is provided to demonstrate the feasibility of the proposed method.

• 전기학회논문지
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• 제56권12호
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• pp.2135-2144
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• 2007

This paper presents system design of the slotless double-side Permanent Magnet Linear Synchronous Machine system (PMLSM) through magnetic field analysis and dynamic modeling. In our analysis, 2-D analytical treatments based on the magnetic vector potential were adopted to predict magnetic field with space harmonics by PM mover magnetization and stator winding current. From these, the design parameters such as inductance, Back-emf, and thrust are estimated. And, the electrical dynamic modeling including synchronous speed is completed by calculation of a DC link voltage in effort to obtain the accurate mechanical power from Space Vector Pulse Width Modulation(SVPWM). Therefore, the system design of PMLSM is performed from estimation of design parameters according to PM size and coil turns in magnetic field and from calculation of a DC link voltage to satisfy base speed and base thrust represented as the maximum output power in dynamic modeling. The estimated values from the analysis are verified by the finite element method and experimental results.

• Journal of Power Electronics
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• 제17권5호
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• pp.1211-1222
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• 2017

In order to decrease the parameter sensitivity of deadbeat direct torque control (DB-DTC), an improved deadbeat direct torque control method for surface mounted permanent-magnet synchronous motor (SPMSM) drives is proposed. First, the track errors of the stator flux and torque that are caused by model parameter mismatch are analyzed. Then a sliding mode observer is designed, which is able to predict the d-q axis currents of the next control period for one-step delay compensation, and to simultaneously estimate the model parameter disturbance. The estimated disturbance of this observer is used to estimate the stator resistance offline. Then the estimated resistance is required to update the designed sliding-mode observer, which can be used to estimate the inductance and permanent-magnetic flux linkage online. In addition, the flux and torque estimation of the next control period, which is unaffected by the model parameter disturbance, is achieved by using predictive d-q axis currents and estimated parameters. Hence, a low parameter sensitivity DB-DTC method is developed. Simulation and experimental results show the validity of the proposed direct control method.

• 한국정보통신학회논문지
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• 제3권3호
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• pp.651-659
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• 1999

본 논문은 PWM 인버터로 구동되는 유도전동기에서 시변의 파라미터 변동에 강인한 속도제어 및 모타토크의 제어기법을 제안하였다. 제어계는 적응알고리즘을 이용한 슬립주파수형 벡터제어에 기초를 두고 있으며, 제어기내에서 슬립주파수연산, 모타토크연산 및 비간섭제어에 사용되는 파라미터가 운선조건에 따라 변함으로써 발생되는 제어기 성능저하를 파라미터 적응동정에 의하여 개선함으로써 제어의 정밀도를 향상시키고자 하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 추계학술대회 논문집 학회본부
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• pp.302-304
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• 1996

In this paper, a new algorithm for sensorless speed control of switched reluctance motor (SRM) is proposed. It is based on the measurement of initial rate of change of phase current. The initial rate of rise of phase current mainly depends up on the phase inductance at the time instant when the phase is excited. Therefore, the measurement of initial di/dt permits rotor position estimation, which is used to trigger the next phase. In the proposed technique, there is no need to generate additional current pulses when a phase is not excited. Therefore, this scheme does not introduce the unwanted braking torque. Also, only one current measurement is made every time a phase is excited. This reduces the computational load on the micro-controller and enhances the speed range of the sensorless drive. By using this scheme it is possible to implement the sensorless control of SRM using low cost micro-controller.

• 한국자동차공학회논문집
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• 제24권1호
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• pp.16-23
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• 2016

The EWB(electronic wedge brake) is one in which the braking force is developed in a wedge and caliper system and applied to a disk and wedge mechanism. The advantage of the wedge structure is that it produces self-reinforcing effect and hence, utilizes minimal motor power, resulting in reduced gear and current. The extent of use of clamping force sensors and protection from failure of the EWB system directly depends on the level of vehicle mass production. This study investigated the mathematical equations, simulation modeling, and failsafe control algorithm for the clamping force sensor of the EWB and validated the simulations. As this EWB system modeling can be applied to motor inductance, resistance, screw inertia, stiffness, and wedge mass and angle, this study could improve the accuracy of simulation of the EWB. The simulation results demonstrated the braking force, motor speed, and current of the EWB system when the driver desired to the step and pulse the brake force inputs. Moreover, this paper demonstrated that the proposed failsafe control algorithm accurately detects faults in the clamping force sensor, if any.

• 한국전자파학회논문지
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• 제29권1호
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• pp.10-19
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• 2018

본 논문에서는 고주파 Radio-Frequency Interference (RFI) 측정용 프로브로 널리 쓰이는 Printed Spiral Coil(PSC)의 고주파 등가회로 모델이 제안되었다. 제안된 모델은 고주파 정합성을 확보하기 위하여 PSC의 설계변수에 기반한 분포 모델로 설계되었으며, 제안된 분포 등가회로 모델을 바탕으로 T-Pi 등가변환을 이용한 PSC의 고주파 해석적 모델 역시 새로이 제안되었다. 제안된 모델의 실제 고주파 RFI 측정 시 효용성을 확인하기 위하여, 임의의 RFI 노이즈 원으로 설계된 마이크로스트립 라인과 PSC 사이의 전달함수를 제안된 모델과 상호 인덕턴스를 결합하여 추출하였다. 제안된 PSC 모델의 자기 임피던스(self-impedance)와 전달함수는 3-dimensional field solver를 이용한 시뮬레이션 및 실 측정으로 검증되었으며, 6 GHz까지 높은 정합성을 보이는 것이 확인되었다. 제안된 PSC의 자기 임피던스 및 전달함수 모델은 GHz 영역의 고주파 통신대역에서의 RFI 측정용 프로브 설계 및 노이즈 간섭 예측에 활용될 수 있다.

• 전력전자학회논문지
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• 제17권3호
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• pp.238-245
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• 2012

This paper presents a sensorless speed control of a 2-phase switch reluctance motor(SRM). The proposed sensorless control scheme is based on the slide mode observer with parameter compensator to improve the estimation performance. In the stand still position, the initial rotor position is determined by pulse current responses of each phase windings and the current difference. In order to determine an accurate initial rotor position, the two initial rotor positions are estimated by the difference of the pulse currents. From the stand still to the operating region, a simple open loop control which determines the commutation sequence by the pulse current of the unexcited phase winding is used. When the motor speed is reached to the sensorless control region, the estimated rotor position and speed by the slide mode observer are used to control the SRM. The flux calculator used in the slide mode observer is designed by phase voltage and the voltage drops in the phase resistance of the winding. The accuracy of the flux calculator is dependent on the phase resistance. For the continuous update of the phase resistance, current gradient at the inductance break point is used in this paper. The error of the estimated rotor position at the current gradient position is used to update the phase resistance to improve the sensorless scheme. The proposed sensorless speed control scheme is verified with a practical compressor used in home appliances. And the results show the effectiveness of the proposed control scheme.