In this paper, a novel stator current based Model Reference Adaptive System (MRAS) estimator for speed estimation in the speed-sensorless vector controlled induction motor drives is presented. In the proposed MRAS estimator, measured stator current of the induction motor is considered as a reference model. The estimated stator current is produced in an adjustable model to compare with the measu...

This paper investigates an improved stator flux linkage observer for sensorless permanent magnet synchronous motor (PMSM) drives using a voltage-based flux linkage model and an adaptive sliding mode variable structure. We propose a new observer design that employs an improved sliding mode reaching law to achieve better estimation accuracy. The design includes two models and two adaptive estimat...

Abstract: In this paper, an estimator scheme for the rotor speed and flux of an induction motor is proposed on the basis of a fourth-order electrical model. It is assumed that only the stator currents and voltages are measurable, and that the stator currents are bounded. There are a number of common terms in the motor dynamics, and this is utilized to find a simple error model involving some au...

Abstract: This paper presents an exact input-output linearization control scheme for rotor speed and rotor flux control of induction motor drive. In this scheme the motor model, is described in the fixed stator frame, and it is linearized, using exact inputoutput linearization technique, allowing a decoupled control of rotor flux and torque. To avoid the use of mechanical sensor, the rotor spee...

This paper presents a speed estimation technique for the permanent magnet synchronous motor drive. A Model Reference Adaptive System (MRAS) has been formed using the instantaneous and steady-state reactive powers to estimate the speed. It has been shown that such unique MRAS offers several desirable features. The proposed technique is completely independent of stator resistance and is less para...

Direct torque control (DTC) of induction motors (IMs) requires an accurate knowledge on the amplitude and angular position of the controlled flux in addition to the information related to angular velocity for velocity control applications. However, unknown load torque and uncertainties related to stator/rotor resistances due to operating conditions constitute major challenges for the performanc...

The primary objective of this paper is to implement a sensorless indirect stator field oriented control (ISFOC) of induction motor drive with rotor resistance tuning. Indeed, the proposed method for simultaneous rotor speed and rotor resistance estimation is based on Luenberger observer (LO). In order to estimate the rotor speed and the rotor resistance, an adaptive algorithm based on Lyapunov ...

LIST OF SYMBOLS L s stator inductance(Primary inductance) L r rotor inductance (Secondary inductance) M mutual inductance Rs stator resistance Rr rotor resistance Rc cable resistance P pole number Vds,Vqs d-axis and q-axis components of the stator voltage vector Vs Vdr,Vqr d-axis and q-axis components of the rotor voltage vector Vr ids, iqs d-axis and q-axis components of the stator current vec...

formance is analyzed for flux vector and indirect field oriented controllers. A new technique-the back electromagnetic force (BEMF) detector-for reducing the adverse effects of stator resistance on field oriented control is presented and evaluated through simulation and experimental results. The BEMF detector is shown to reduce the impact of the stator resistance and provides a stator resistanc...

Estimation of rotor resistance rapidly and accurately has received a lot of attention due to its significance in improving the performance of induction motor(IM) vector control system. In this paper, algorithm of estimating rotor resistance of IM based on extended Kalman filter(EKF) is presented. The algorithm can estimate the rotor resistance on line by measuring the voltage, current and speed...