• 대한전기학회논문지
• /
• 제39권10호
• /
• pp.1066-1074
• /
• 1990

본 논문에서는 유동전동기에 최근에 개발된 비선형 제어이론을 적용시켜 회전자 속도와 회전자 자속사이에 간섭이 일어나지 않는 선형 시스템으로 변환시킴으로써 제안한 제어기가 유도전동기를 고성능뿐만 아니라 고효율로 제어할 수 있음을 수학적인 분석, 시뮬레이션, 그리고 실험을 통해 보였다. 제안한 제어기는 d-p동기 회전축과 x-y고정자축 사이의 변환, 전기각 속도의 적분, 그리고 전압방정식에서 역기전력과 결합항의 보상등이 필요치 않기 때문에 기존 벡터 제어기보다 계산이 간단하다는 장점을 갖고 있고 특히 전동기 매개변수의 변화에 강인한(robust) 특징을 갖고 있다. 본 논문이 제안한 설계방법은 최근에 개발된 이론인 특이섭동기법(singular perturbation technoque)과 비간섭 궤환제어(noninteracting feedback control)에 기초를 두고 있는데 실제로 이 이론들이 유도 전동기의 속도 및 효율제어에 효과적으로 적용됨을 본 논문을 통해 보이고 있다.

• Journal of Power Electronics
• /
• 제11권6호
• /
• pp.824-836
• /
• 2011

A new fault-tolerant control topology for open-loop motor-drive systems with Delta-connected stator windings is introduced in this paper. This new control topology enables the operation of a three-phase induction machine as a two-phase machine fed by a three-phase inverter upon a failure in one of the motor phases. This topology utilizes the "open-Delta" configuration to independently control the current in each of the two remaining healthy phases. This new control technique leads to the alleviation of any torque pulsations resulting from the consequences of the asymmetrical conditions associated with this class of faults.

• Journal of Power Electronics
• /
• 제4권4호
• /
• pp.217-227
• /
• 2004

A robust controller that combines the merits of the feed-back, feed-forward and model-following control for induction motor drives utilizing field orientation control is designed in this paper. The proposed controller is a two-degrees-of­freedom (2DOF) integral plus proportional & rate feedback (I-PD) speed controller combined with a model-following (2DOF I-PD MFC) speed controller. A systematic mathematical procedure is derived to find the parameters of the 2DOF I-PD MFC speed controller according to certain specifications for the drive system. Initially, we start with the I-PD feed­back controller design, then we add the feed-forward controller. These two controllers combine to form the 2DOF I-PD speed controller. To realize high dynamic performance for disturbance rejection and set point tracking characterisitics, a MFC controller is designed and added to the 2DOF I-PD controller. This combination is called a 2DOF I-PD MFC speed controller. We then study the effect of the 2DOF I-PD MFC speed controller on the performance of the drive system under different operating conditions. A computer simulation is also run to demonstrate the effectiveness of the proposed controller. The results verify that the proposed 2DOF I-PD MFC controller is more accurate and more reliable in the presence of load disturbance and motor parameter variations than a 2DOF I-PD controller without a MFC. Also, the proposed controller grants rapid and accurate responses to the reference model, regardless of whether a load disturbance is imposed or the induction machine parameters vary.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
• /
• pp.23-28
• /
• 1998

We propose a nonlinear feedback controller that can control the induction motors with high dynamic performance by means of decoupling of motor speed and rotor flux. The nonlinear feedback controller needs the information on some motor parameters. Among them, rotor resistance varies greatly with machine temperature. A new recursive adaptation algorithm for rotor resistance which can be applied to our nonlinear feedback controller is also presented in this paper. The recursive adaptation algorithm makes the estimated value of rotor resistance track its real value. Some simulation results show that the adaptation algorithm for rotor resistance is robust against the variation of stator resistance and mutual inductance. In addition, it is computationally simple and has small estimation errors. To demonstrate the practical significance of our results, we present some experimental results.

• Journal of Power Electronics
• /
• 제9권5호
• /
• pp.791-799
• /
• 2009

This paper presents a time-varying sinusoidal disturbance compensation method (based on an adaptive estimation scheme) for induction motor drives fed by a matrix converter. In previous disturbance accommodation methods, sinusoidal disturbances with unknown time-invariant frequencies have been considered. However, in the new method proposed here, disturbances with unknown time-varying frequencies are considered. The disturbances can be estimated by using a disturbance accommodating observer, and an additional control input is added to the induction machine drive. The stability analysis is carried out considering the disturbance estimation error and simulation results are shown to illustrate the performance of the proposed solution.

• 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.

• 대한전기학회논문지
• /
• 제45권3호
• /
• pp.365-373
• /
• 1996

This paper presents the effects of rotor time constant variation and the on-line tuning algorithm of the rotor time constant. If the value of the rotor time constant is set incorrectly, the IFOC (Indirect Field Oriented Control)scheme exhibits deteriorated performance according to the wrong slip command. These variation effects of the rotor time constant are caused by the slip calculator where it is known that the rotor time constant play an important role in the aligned rotor flux. Using the two torque angles (stationary torque angle, rotating torque angle), the variation of the rotor time constant is identified, and the rotor time constant of the controller is tuned to the proper value of the machine. As the result, with the proposed algorithm, the dynamics of the deteriorated IFOC system, where the rotor time constant is varied, is improved. For the purpose of the validity of this proposed algorithm, the computer simulations and the experiments have been performed and the explanation of the results is presented. (author). refs., figs., tab.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1992년도 하계학술대회 논문집 B
• /
• pp.692-694
• /
• 1992

This paper describes a robust flux bonging scheme which utilizes the windings of the machine itself to implement field orientation control of SLIM (Single-sided Linear Induction Motor). By subtracting the voltage across adjacent motor coils of the same phase which are named STATOR TAPPED COIL, a flux signal is obtained which is insensible to stater resister drop at a low speed that exerts a bad Influence on field orientation. The method using STATOR TAPPED COIL has been implemented at SLIM in our laboratory, and experimental results are being scrutinized.

• 전력전자학회논문지
• /
• 제14권4호
• /
• pp.293-298
• /
• 2009

본 논문은 이중여자 풍력발전기를 안정적으로 계통에 투입하는 알고리즘을 제안하였다. 발전기가 계통과 연계되는 순간 발전기의 내부 파라미터 값의 변동이 발생하며, 이는 계통 투입 전 발전기 파라미터에 근거한 RSC(Rotor Side Converter)측 전류제어기 이득 값에 영향을 준다. 이러한 영향으로 인하여 계통 투입 시 전류제어가 불안정하게 되거나, 전류제어 응답성이 낮게 된다. 따라서 계통투입 전 발전기 파라미터를 이용한 전류제어기 이득 값은 투입 후 바뀌어야 한다. 특히 회전자 전류제어기 성능은 순간 저전압 발생등 예상하지 않은 외란에 대하여 빠른 응답성을 필요로 한다. 따라서 본 논문에서는 계통투입 전 후의 RSC측 전류제어기의 이득 값을 달리하여 안정적인 계통 투입이 가능하도록 하는 알고리즘을 시뮬레이션과 실험으로 증명하였다.