Mathematical Model Of Induction Motor Research Articles

Induction Motor Stator Fault Detection by a Condition Monitoring Scheme Based on Parameter Estimation Algorithms

This article presents a simple, low-cost, and effective method for the early diagnosis of stator short-circuit faults. The approach relies on the combination of an induction motor mathematical model and parameter estimation algorithm. The kernel of the method is the efficient search for the characteristic parameters that indicate stator short-circuit faults. However, the non-linearity of a machine model may imply multiple local minima of an objective function implemented in the estimation algorithm. Taking this into consideration, the suitability of two industry-proven optimization algorithms (pattern search algorithm and genetic algorithm) as applied in the proposed condition monitoring method was investigated. Experimental results show that the proposed diagnosis method is capable of detecting stator short-circuit faults and estimating level and location of faults. The study also indicates that the proposed method is robust to motor parameters offset and unbalanced voltage supply. Application of the pattern search algorithm is suitable for a continuous monitoring system, where the previous result can be used as starting point of the new search. The genetic algorithm requires longer computation time and is suitable for the offline diagnostic system. It is not sensitive to the starting point, and achieving global solution is guaranteed.

СИСТЕМА УПРАВЛЕНИЯ ТЯГОВЫМ АСИНХРОННЫМ ДВИГАТЕЛЕМ С МИНИМИЗАЦИЕЙ МОЩНОСТИ ПОТЕРЬ

The mathematical model of induction motor taking power losses in stator and rotor iron and typical non-linearity is designed. The algorithm of optimal flux linkage reference providing power loss minimization is developed with regard to vector control. The induction motor stator current and voltage limits, the diesel generator unit power are chosen as a limiting factor. The tractive induction motor control system providing the direct regulation of wheel sliding for protection from slipping and having the internal system of power loss minimization is designed. The results of simulation are presented.

The Control System for Three-Phase Induction Motors Based on Stator Flux Orientation

In this paper, the mathematical model of induction motor based on stator field orientation in synchronous frame is introduced. To resolve the question of relay, the d-axis current direct calculation is adopted to replace traditional decoupler. Fix threshold double-integrator based on coordinate transformation is used to eliminate integrator saturation. SVPWM based on 600 coordinate system is developed to simplify calculation. The control system based on stator flux orientation is simulated by MATLAB. The simulation result shows that the system has a fast dynamic response and steady characteristics.Nomenclature

Squirrel Cage of Induction Motors Simulation via Simulink

This study presents Simulink implementation and mathematical model of squirrel cage induction motor. Induction motor models are generally available in form of d-q model in literature for Simulink simulations. But in this study the model include rotor bars and end-ring near the stator windings. So, the rotor bars and end-ring data (currents, voltages etc.) are accessible and can be investigated. And the rotor bars and end-ring parameters are verification and made optimization. In the solution the number of rotor bars determines the dimension of inductance matrix in the motor model. Because simulated motor has 18 rotor bars, dimension of this matrix is 22x22. Each component of the matrix changes according to motor position. Calculating of inverse of the matrix is necessary for every time period. This process is very difficult in Simulink by using function blocks. In the present study m-file block is used instead of function block. So, solution of mathematical model of squirrel-cage induction motor is implemented by Simulink. The simulation results are given with the model used in start-up condition. The results show that the proposed method is used simulation of the induction motor with squirrel-cage. achieved by utilizing separate d-q axis models (2). But in present study the aimed model include rotor bars and end-ring together with the stator windings. So, the rotor bars and end-ring data (currents, voltages etc.) are accessible and can be investigated. And the rotor bars and end-ring parameters are verification and made optimization. The facilities provided by the Simulink software of MATLAB are used to implement the block diagram which represents the governing squirrel cage induction motor mathematical model differential equations with cage model. The main advantage of the SIMULINK over other programming software is the simulation model is built up systematically by means of basic function blocks. A set of machine differential equations can thus be modeled by interconnection of appropriate function blocks, each of which performing a specific mathematical operation. The simulation model can be easily developed by addition of new sub-models to cater for various control functions. The following assumptions were made for the derivation of the appropriate mathematical model; -The magnetic permeability of iron is considered to be infinite.

Rotor Speed and Stator Resistance Identification of Direct Torque Control for Induction Motor Based on Mutual MRAS

Based on the dynamic mathematical model of induction motor, the mutual model reference adaptive system method (MRAS) for rotor speed identification is proposed to implement a speed sensorless direct torque control of induction motor. The model reference adaptive theory is flexibly used in the rotor speed and the stator resistance online identification. The reference model and adjustable model used in the mutual MRAS scheme are interchangeable. Therefore, The induction motor speed sensorless direct torque control system can obtain high-precision speed identification. Computer simulations and experimental results show that the method can solve the problems of speed control accuracy and system stability under the influence of motor parameter variation. The low speed performance of DTC is also improved.

Three-phase mathematical model of induction motor

A three-phase mathematical model of induction motor based on description of processes in all three phases of the motor is considered. The factor that unites all three phases is the resulting magnetomotive force created by the stator and rotor currents and the main magnetic flux that passes through the air gap and rotates in the plane of the cross section of the induction motor.

Rotor Speed Adaptive Identification of Direct Torque Control for Induction Motor

Based on the dynamic mathematical model of induction motor, the mutual model reference adaptive system method (MRAS) for rotor speed identification is proposed to implement a speed sensorless direct torque control. The model reference adaptive theory is flexibly used in the rotor speed and the stator resistance online identification. The reference model and adjustable model used in the mutual MRAS scheme are interchangeable. Therefore, the control system can obtain high-precision speed identification. Simulation results show the method can solve the problems of speed control accuracy and system stability under the influence of motor parameter variation. The low speed performance of DTC is also improved.

Mathematical Modelling of Induction Motor Transient Processes During Stator Winding Interruption

Mathematical Modelling of Induction Motor Transient Processes During Stator Winding InterruptionThis research presents induction motor mathematical model in coordinate axis's α, β, which allows to learn transient processes in rotor and stator circuits in the conditions of stator windings opening. Such kind of researches is nowadays actual due to impossibility of main calculated values measuring directly, but only on the stator terminals. Induction motor mathematical model forms Park-Gorev equations in α, β coordinate axis. It is preferable to use this coordinate system because it allows comparing the results of mathematical modeling in one of the phases with experimental data without transformations.

The complex controller for three-phase induction motor direct torque control

This paper proposes a design and tuning method for a complex gain controller, based on the three-phase induction motor mathematical model complex transfer function to be used in the direct torque control at low speed which is a problem so far. The design and tuning of the complex gain is done by using the closed loop system frequency-response function. Experimental results are presented to validate the controller and operation at low speed is also explored.

Vector Control System of Induction Motor Based on Fuzzy Control Method

Aiming at non-linear model of multivariable induction motor, traditional PI method is hard to achieve satisfactory control purpose. Fuzzy control can carry the real-time control on system without the accurate mathematical model of induction motor. This paper elaborates induction motor vector control system and the basic principle of the fuzzy PI, making use of fuzzy reasoning, automatically adjusting the controller’s parameters. Simulation results prove that fuzzy PI controller is superior to traditional PI controller in the aspect of response speed, steady state accuracy and disturbance attenuation.

Analysis of Induction Motors Fed from Constant Current Source Taking Core-Loss and Saturation into Consideration

In this paper, a mathematical model of induction motor fed from constant current source as influenced by core-loss and saturation is presented. In the model, the equivalent core-loss resistance is split for the first time among the stator and rotor circuits. The actual value of the magnetizing inductance in the motor model is considered to account for the magnetic-circuit saturation. The transient and steady-state characteristics of an induction motor supplied from a constant lein current are presented. For completeness, the characteristics are compared with those of the same motor when fed from constant voltage source. The effect of core loss on motor performance is significant when the motor is fed from constant current source. Moreover, the effect of magnetic-circuit saturation is to improve the performance when the motor is fed from constant current source. Comparison between experimental and calculated steady-state performances are also presented.

Proposition of New Mathematical Models of Induction Motor Using Minimum Number of Parameters

This paper proposes new mathematical models of induction motor, which is supposed to generate precisely torque under vector control. The proposed models for controlled motor have the following proper features in perspective of preciseness and compactness. They guarantee the same relation between stator signals of voltage and current as conventional T-type model consisting of five parameters. Parameters forming new models are reduced to a set of four such as stator resistance, inverse of rotor time constant, stator inductance, and stator total leakage inductance or another set of four related uniquely with them. They can be uniquely determined by the stator signals, in terms of which all controller parameters of vector control system can be designed.