http://w3.gazi.edu.tr/~icolak/folders/SinghGK-atif.pdf

Self-excited induction generator research—a survey

A review of the literature suggests that modeling of induction machines with saturation has received considerable attention Most of these models are very application specific None of them, however, seems to be completely adequate for the purpose of fault diagnosis This is because for a noninvasive detection technique such as Motor Current Signature Analysis (MCSA), one has to detect different frequency components in the line current of the machine Incorporation of saturation in the induction machine model will help in identifying and analyzing harmonics in the line current spectra that may arise due to the interaction of saturation with a specific fault The present paper attempts to create such a model The model uses modulation of air-gap permeance in order to emulate saturation Modified winding function approach (MWFA) has been used to model the induction machine with saturation To demonstrate the effectiveness of the model, certain high-frequency harmonics that can be predicted theoretically are shown to be present in the line current of the simulated machine Experimental results also confirm the presence of these harmonics The author plans to extend this model in the future for fault analysis

A detailed model of induction machines with saturation extendable for fault analysis

This paper presents an induction machine mathematical model which includes the magnetic saturation effects. Saturation is included by using the so called "magnetic harmonic functions". These functions are obtained through a joint procedure of experimental tests and the mathematical model itself. Experimental tests and simulation results of the induction machine operating at no load synchronous speed and as a capacitor self excited generator are compared to validate the theoretical developments. All the results shown in the paper are for constant shaft speed, therefore only the machine's electrical transient behavior are studied.

A new strategy for induction machine modeling taking into account the magnetic saturation

A transient model of a squirrel-cage induction machine, including air-gap flux saturation harmonics, is presented in this paper. The machine model is based on a flux model, where the winding magnetizing fluxes are directly calculated from the resultant air-gap magnetomotive force, avoiding the use of complicated inductance harmonics. The effects of the fundamental and third harmonic components of the air-gap flux are incorporated in the model by two saturation factors. Moreover, the saturation effects are incorporated in the machine's torque equation, allowing the model to investigate the machine's performance under any load condition. The machine parameters, including saturation data, are obtained via the conventional no-load and locked-rotor tests, with access to the stator neutral connection. The proposed model is validated by experimental results for a squirrel-cage machine and can be used to predict machine transient states.

Transient Modeling of Squirrel-Cage Induction Machine Considering Air-Gap Flux Saturation Harmonics

Five-phase induction machines are generally modeled using multiple dq planes or using a phase variable model. This paper considers modeling five-phase induction machines using a voltage-behind-reactance (VBR) configuration. This configuration lends itself suitable for time-domain circuit-based simulators as the MATLAB/Simulink SimPowerSystems (SPS) toolbox. The stator electrical dynamics are represented in five-phase coordinates, while the rotor electrical circuit is modeled using rotor flux linkage as the state variable and expressed in the dq stator reference frame. The VBR model is equivalent to a conventional dq model; however, it facilitates the connection of an external inductance without affecting numerical accuracy and calculation efficiency. It also facilitates the simulation of different winding connections, series-connected multimotors, and open phase(s) conditions. The model is, first, derived for a magnetically linear system and then it is extended to include the effect of magnetic saturation. The flux correction method is used to represent the effect of magnetic saturation with a simple modification to represent the effect of cross coupling between fundamental and third sequence planes due to saturation effect. The dynamic cross saturation is considered by adding compensating terms that depend on magnetizing inductance variation. The proposed model is experimentally verified using a prototype 1.5-hp five-phase induction machine under different operating conditions.

A Voltage-Behind-Reactance Model of Five-Phase Induction Machines Considering the Effect of Magnetic Saturation

This paper proposes a new model for saturated induction motors. The saturation effects are incorporated in the magnetizing inductance and the stator mutual inductances, taking into account the nonuniform distribution of magnetic saturation within the motor core. The proposed model can be used to analyze the manner in which the induction motors interact with the supply network or power source, since it can predict the motor current/voltage harmonics produced by magnetic saturation. Experimental tests show that the proposed model represents with reasonable accuracy (8%) the motor saturation effects at nominal stator voltage as well as for overvoltage operation.

Modeling and simulation of saturated induction motors in phase quantities

This paper proposes a new automated method for determining the electric parameters of induction motors. Unlike the IEEE 112 standard method for parameter determination, the proposed method is more convenient since it is neither necessary to use special mechanical devices for blocking the motor shaft during tests nor to perform manual handling. To verify the proposed method, experimental tests have been done on a 5 HP induction motor.

A. Charette

Papers

Modeling and simulation of saturated induction motors in phase quantities

A new automated method for estimation of induction motor parameters