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...

single-phase squirrel cage and three-phase induction electromotors are the most popular electromotors used in industry from long ago. when an induction motor starts with direct connection method, it takes a lot of current from the power supply (several times the nominal current); so, several methods have been devised to start such electromotors. these methods either reduce the voltage of the st...

Effects of magnetic saturation on various equivalent circuit models of an induction motor are studied. The parameters of 2.2-kW and 37-kW motors with closed rotor slots are analyzed using finite element computations. Both skewed and unskewed rotor slots are studied. The magnetizing inductance not only depends on the main flux, but is also dependent on the rotor current, especially if the rotor ...

The rotor eddy current losses of a high-speed permanent magnet synchronous motor reduce the efficiency of the motor and increase the temperature rise of the rotor. In severe cases, the permanent magnet of the rotor can be demagnetized, affecting the safe operation of the motor. In this paper, an analytical model of rotor eddy current losses calculation based on Maxwell equations is introduced. ...

Indirect Field Oriented Control (IFOC) is known to produce high performance in induction Motor (IM) drives by decoupling rotor flux and torque producing current components of stator current. The decoupling control between the rotor flux and the torque is no longer achieved in terms of stator current components this paper introduces a decoupled rotor flux and torque control based on the magnetiz...

A new close loop current model flux observer is designed to estimate the rotor flux, position and velocity of an induction machine. The current observer includes carefully designed sliding mode functions which are derivative of the fluxes along the and axes. Therefore, when the estimated current converges to the measured one, the flux estimation is a mere integration of the sliding mode functio...

This paper suggests novel sensorless speed estimation for an induction motor (IM) based on a stator current model reference adaptive system (IS-MRAS) scheme. The IS-MRAS scheme uses the error between the reference and estimated stator current vectors and the rotor speed. Observing rotor flux and the speed estimating using the conventional MRAS technique is confronted with certain problems relat...

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...

The detection of broken rotor bars in three-phase squirrel cage induction motors by means of current signature analysis is presented. In order to diagnose faults, a Neural Network approach is used. At first the data of different rotor faults are achieved. The effects of different rotor faults on current spectrum, in comparison with other fault conditions, are investigated via calculating Power ...