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Abstract: An induction motor model which includes stator leakage reactance saturation, rotor leakage reactance saturation and magnetizing reactance saturation is presented. This improved model is based on experimental data from 96 motors. The power range of the motors is between 11 and 90kW. The effects on the torque–speed and current–speed curves of each kind of saturation have been studied. In addition, the parameters of magnetizing reactance saturation and stator leakage reactance saturation have been studied for each motor, and an average value and its dispersion for each parameter are given. This model is considerably more accurate than other models. In particular, it explains the significant differences between theoretical and experimental torque–speed curves in the braking regime (s >1). [Copyright &y& Elsevier]

A very simple method for determining squirrel-cage induction motor parameters is presented, and some problems in the determination of parameters with two methods proposed in IEEE Standard 112 are discussed and clarified. The double-cage model is used to describe the motor response for the entire operating range. Equivalent circuit parameters are calculated from data of three tests: no-load test, locked-rotor test and overload test. The method has the advantage of not requiring torque measurements. It is formulated as an iterative algorithm, and has been tested with 16 motors of different power ratings, showing very good convergence. The influence of measurement errors on the stability of the proposed method has been studied and its behaviour is very good [ABSTRACT FROM AUTHOR]

This paper presents a numerical method for the estimation of induction motor double-cage model parameters from standard manufacturer data: full load mechanical power (rated power), full toad reactive electrical power, breakdown torque, and starting current and torque. A model sensitivity analysis for the various electrical parameters shows that stator resistance is the least significant parameter. The nonlinear equations to be solved for the parameters determination are formulated as a minimization problem with restrictions. The method has been tested with 223 motors from different manufacturers, with an average value of the normalized residual error of 1.39 . 102. The estimated parameters of these motors are graphically represented as a function of the rated power. [ABSTRACT FROM AUTHOR]

This paper analyzes the numerical identifiability of the electrical parameters of induction machines. Formulations of the single-and double-cage induction machine, with and without core-losses in both models, are developed. It is shown the impossibility to identify all the parameters of these models when only external measurements (voltage, current, speed, and torque) are used. One proposed solution is the formulation of machine equations by using the minimum number of parameters (which are identifiable parameters). As an application example, the parameters of a double-cage induction machine are identified using steady-state measurements corresponding to different angular speeds. [ABSTRACT FROM PUBLISHER]

Abstract: This paper presents a method to compute the parameters of a transformer model with saturation using the voltage and current waveforms of an inrush test and a no-load test. The transformer is modeled with their electric and magnetic equivalent circuits and a single-valued function that characterizes its non-linear magnetic behavior. A 3-kVA single-phase transformer and a 5-kVA three-phase three-legged transformer have been tested in the laboratory. The method to obtain the parameters of the non-linear flux–current relation that characterize the saturation has been described in the paper. The analytical function used to adjust the experimental measurements fits them very well. [Copyright &y& Elsevier]