• 전력전자학회논문지
• /
• 제5권5호
• /
• pp.451-458
• /
• 2000

이중여자 유도기를 계통선 연계형 풍력발전 시스템에 적용할 때, 고정자는 계통선에 그리고 회전자는 제어 시스템에 연결된다. 이때 고정자에는 일정전압과 주파수가 걸리기 때문에, 고정자측에 는 거의 일정한 고정자 자속값을 갖는다. 또한 고정자 자속을 기준으로 고정자 전류와 회전자 전류를 이용하여 슬립각을 추정하고, 이를 이용하여 고정자측에 출력되는 전력을 제어한다. 제안한 알고리즘의 타당성을 검증하기 위해 컴퓨터 시뮬레이션과 실험을 통하여 이를 입증한다.

• 전기학회논문지
• /
• 제67권10호
• /
• pp.1308-1316
• /
• 2018

Accurate tuning of parameter is very important in vector-controlled induction motor. Among the parameters of induction motor, detuning of rotor resistance used in controller design deteriorates drive performance. This paper presents a novel rotor resistance estimation strategy using slip angular velocity in vector-controlled induction motor drives. The slip angular velocity can be calculated by two methods. Firstly, it can be induced from the rotor voltage equation. Secondly, it can be induced from the difference between synchronous angular velocity and rotor angular velocity. The first method includes the rotor resistance, while the second method dose not include this parameter. From this fact, the rotor resistance can be identified by comparing the slip angular velocities in the two methods. In the tuned states of the rotor resistance, performances of flux estimator and speed drive are discussed. The simulation and experimental results are given to verify the validity of the proposed method in various situations.

• 전력전자학회논문지
• /
• 제24권1호
• /
• pp.25-32
• /
• 2019

Recent high-end treadmills are demanding stable performance at lower speeds. In this study, a slip control-based induction motor sensorless algorithm for treadmills, which have heavy load variations, is proposed. A modified Gopinath flux estimator is used to evaluate the rotor flux. Results indicate that a good speed regulation performance is achieved even at a low speed of approximately 3 Hz with a nominal exercise load of 90 kg body weight. The slip calculation method in the stationary coordinate system is adopted to improve the control stability. The proposed algorithm is verified throughout the simulation study using PSIM, and the experimental test consists of a commercial treadmill system.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2003년도 추계학술대회 논문집
• /
• pp.123-126
• /
• 2003

This paper proposes a speed-sensorless induction motor control system using the rotor flux error. The rotor flux observer uses the reduced- dimensional state estimator technique instead of directly measuring the rotor flux. The estimated rotor speed is obtained directly from the electrical frequency, the slip frequency, and the rotor speed compensation with the estimated q-axis rotor flux. To precisely estimate the rotor flux, the actual value of the stator resistance, whose actual variation is reflected, is derived. For fast calculation and improved performance of the proposed algorithm, all control functions are implemented in software using a digital signal processor (DSP) with its environmental circuits. Also, it is shown through experimental results that the proposed system gives good performance for the speed-sensorless induction motor control.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
• /
• 제54권3호
• /
• pp.154-161
• /
• 2005

This paper proposes a speed-sensorless induction motor control system using a rotor speed compensation. To explain the proposed system, this paper describes an induction motor model in the synchronous reference frame for the vector control. The rotor flux is estimated by the rotor flux observer using the reduced-dimensional state estimator technique. The estimated rotor speed is directly obtained from the electrical frequency, the slip frequency, and the rotor speed compensation with the estimated q-axis rotor flux. The error of the rotor time constant is indirectly reflected in the rotor speed compensation using the compensation of the flux error angle. To precisely estimate the rotor flux, the actual value of the stator resistance, whose actual variation is reflected, is derived. An implementation of pulse-width modulation (PWM) pulses using an effective space vector modulation (SVM) is briefly mentioned. For fast calculation and improved performance of the proposed algorithm, all control functions are implemented in software using a digital signal processor (DSP) with its environmental circuits. Also, it is shown through experimental results that the proposed system gives good performance for the speed-sensorless induction motor control.