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Vector control has very good transient and steady‐state performance in induction motors. Furthermore, most direct stator flux orientation methods do not need speed information and these methods are not sensitive to parameters other than stator resistance. However, the performance of these control strategies depends on accurate estimation of the stator flux. The voltage model is one of the methods used for estimating the stator flux. In this paper, we discuss the integration methods for the voltage model which have an open integration problem, and those which have magnitude and angle errors in the stator flux. We then describe a new compensator to solve the problems associated with the integrator. The limiting level in the feedback loop of this compensator is estimated by using the intersection points of the two phases of the stator flux. The proposed new compensation method, which is computationally fast, has been both simulated and implemented on an experimental system. Experimental results show excellent performance, especially near zero speed.

According to bidirectional ability, wind application are having variable acceleration which connected large quantity of wind ability bearing system with doubly-fed induction generator (DFIG) fed by the two-stage cast converter (TSMC) system, the accentuation action for TSMC and arithmetic standard for DFIG are all deduced. The purpose of this study is for, stator accelerated action in Doubly fed induction generator and controlled by the Two Stage Cast Converter for better control.

The purpose of this study is for, stator accelerated action in Doubly fed induction generator and controlled by the Two Stage Cast Converter for better control.

Then, the beginning ancestor was set up to verify this system; the allotment of the filigree beginning after-effects are offered beneath no-load and the three plan states.

These after-effects apparent by the fact that the arrangement fed by TSMC-DFIG could apprehend the safe ability bearing accumulated to the filigree in the sub-synchronous, synchronisation and super-synchronous state; meanwhile generated sinusoidal describes the displacement factor.

The purpose of this paper is to compare different types of electric motor drives for high-efficiency applications: an induction motor (IM) drive, a synchronous reluctance motor drive and a permanent magnet-assisted synchronous reluctance motor drive. An innovative field-oriented analysis technique is applied to estimate the performance of the IM drive. This method of analysis is particularly advantageous in comparing the IM performance to those of synchronous machines.

The comparison among the capabilities of the three electric drives is carried out combining both analytical and finite element methods.

From the analysis, it results that the REL motor exhibits higher torque density than IM, but lower losses since there are no Joule losses in the rotor. On the contrary, the REL motor exhibits a very power factor, which corresponds to a high-volt-ampere ratings of the inverter that supplies the motor itself.

A new analysis technique is adopted to investigate and compare the energy efficiency performance of different machines.

To purpose of this paper is to introduce a procedure to compute the d‐ and q‐axis parameters of the induction motor.

A finite element procedure, based on the d‐ and q‐axis model of the induction motor is adopted.

Such a procedure is well suited to analyse IM with anisotropic rotor, where an intentionally created saliency is introduced in the rotor bar geometry, so as to detect the IM rotor position without sensor.

The proposed procedure allows one to evaluate the sensorless control capability of the IM. It will be useful for both analysis of the IM performance and design of the machine itself.

This paper aims to propose an 18th-order nonlinear model for doubly fed induction generator (DFIG) wind turbines. Based on the proposed model, which is more complete than the models previously developed, an extended Kalman filter (EKF) is used to estimate the DFIG state variables.

State estimation is a popular approach in power system control and monitoring because of minimizing measurement noise level and obtaining non-measured state variables. To estimate all state variables of DFIG wind turbine, it is necessary to develop a model that considers all state variables. So, an 18th-order nonlinear model is proposed for DFIG wind turbines. EKF is used to estimate the DFIG state variables based on the proposed model.

An 18th-order nonlinear model is proposed for DFIG wind turbines. Furthermore, based on the proposed model, its state variables are estimated. Simulation studies are done in four cases to verify the ability of the proposed model in the estimation of state variables under noisy, wind speed variation and fault condition. The results demonstrate priority of the proposed model in the estimation of DFIG state variables.

Evaluating DFIG model to estimate its state variables precisely.

This work proposes a method to improve the estimation performance at standstill and low speed operations of an adaptive fuzzy logic speed‐sensorless field‐oriented control of an induction motor.

First, the speed estimation algorithm presented in Tursini et al., which it has been designed to consider constant speed operation, is modified in an attempt to reduce the estimation error. Second, the speed regulation by fuzzy logic controller (FLC) with fuzzy adapted gains (FAG) is proposed for speed regulation. The main features of the proposed algorithm are investigated and compared with those of the algorithm of (Tursini) considering different dynamic operating conditions.

Simulation results clearly show the performance of the proposed algorithm.

The proposed scheme is recommended for applications requiring robust speed control and field‐orientation even in the presence of some key parameter deviations.

The purpose of this paper is to investigate the influence of stator and rotor pole number combinations together with the flux-barrier layers number on the performance of synchronous reluctance machine with emphasis on output torque capability and torque ripple.

AC synchronous reluctance machine (SynRM) or permanent magnet assisted SynRM presently receives a great deal of interest, since there is less or even no rare-earth permanent magnet in the rotor. Most of SynRM machines employ a stator that is originally designed for a standard squirrel cage induction motor for a similar output rating and application, or the SynRM machine with 24-slot, four-pole are often directly chosen for investigation in most of the available literature. Therefore, it is necessary to investigate the influence of stator and rotor pole number combinations together with the flux-barrier layers number on the performance of SynRM machine with emphasis on output torque capability and torque ripple.

The average torque decreases with the increase of the pole numbers but remain almost constant when employing different stator slot numbers but with the same pole number. In addition, the torque ripple decreases significantly with the increase of the stator slot number. The machine with double-layer flux-barrier in the rotor has the biggest average torque, while the machines with three- and four-layer flux-barrier in the rotor have almost the same average torque but their value is slightly smaller than that of machine with double-layer flux-barrier. However, the machine with three-layer flux-barrier has the lowest torque ripple but the highest torque ripple exists in the machine with double-layer flux-barrier.

The purely sinusoidal currents are applied in this analysis and the effects of harmonics in the current on torque ripple are not considered in this application.

This paper has analyzed the torque ripple and average torque of SynRMs with considering slot/pole number combinations together with the flux-barrier number.

To provide a new and simple inverse rotor time constant identification method which can be used to update an indirect rotor field oriented controlled (IRFOC) induction motor algorithm.

Two different equations are used to estimate the rotor flux in the stator reference frame. One of the equations is a function of the rotor time constant, rotor angular velocity and the stator currents. The other equation is a function of measured stator currents and voltages. The equation that uses the voltage and the current signals of the stator serves as reference model, however, the other equation works as an adjustable model with respect to the variation of the rotor time constant. Voltage signals used in the reference model equation are obtained from the measured DC bus voltage and the inverter gating signals. The proposed scheme is verified using a MATLAB/SIMULINK model for two different motors and experimentally using a DSP development tool (MCK 243) supplied by Technosoft S.A.

The proposed estimator was able to successfully track the actual value of the inverse rotor time constant for different load torque and speed operating conditions. Increased oscillations in the estimated inverse rotor time constant appeared at lower speeds (below 10 per cent of rated speed) due to drift in a PI regulator (used at the estimator side), which was tuned under rated operating conditions and using parameters nominal values.

This estimation scheme is limited when near zero speed operation is demanded; otherwise it gives a simple and practical solution. A suggested way out of this, is to provide a self‐tuning controller that can automatically adjust even for zero speed operation, or to automatically disconnect the estimator and take the most updated value as long as the operating speed is below a predetermined value.

This paper presented a new inverse rotor time constant estimator for an IRFOC induction motor application and in conjunction rotor flux was estimated without voltage phase sensors.

The purpose of this paper is to present a doubly fed induction machine (DFIM) operating in motor mode and supplied by two voltage source inverters (in stator and rotor sides).

The aim is to analyze the current sensor fault effects on the stator flux‐oriented control according to the current input‐output decoupling. This justifies the necessity of a reconfiguration control in order to satisfy the system service continuity. Also, a theoretical development of sensitivity coefficients gives an idea about control robustness toward a current sensor fault.

This paper emphasizes the system performance close dependency to the current sensor outputs accuracy. Moreover, simulation results point out the operation system deterioration in case of current sensor fault, which leads in most cases to its shut down in contrast with the industrial expectations. In this paper, the suggested solution is the DFIM speed drive control reconfiguration when a current sensor fault occurs in order to ensure system service continuity. MATLAB‐Simulink simulation results illustrate the system behavior before and after a current sensor fault. System performance preservation is performed after control reconfiguration.

This solution presented in this paper is relevant, especially because of its simplicity.

The present paper will discuss newly developed fully digital sensorless induction motor and permanent magnet motor synchronous motor drives, which employ natural field orientation (NFO). So far only vector‐type of NFO induction motor drives have been discussed in the literature, and very limited experimental results have been shown. In addition, the paper will also discuss new sensorless DTC‐type of NFO induction motor drives (NFO‐DTC drives). Using fully digital implementations of the new NFO‐type induction motor and permanent magnet drives, experimental results will be shown for various operating conditions, including slow and fast reversals at very low speed. Robustness to parameter deviations will also be demonstrated. The developed new types of NFO drives can also work at zero stator frequency and sustained zero frequency operation will also be demonstrated. The drives have been tested in basically two environments: where the load is a dc motor; and where a crane drive is implemented. In contrast to other sensorless crane drives, which develop stability problems, it was found that the new NFO drives can operate in a stable manner under all operating conditions including zero frequency. This allows for many new applications.