Modelling of rotorbars with skin effect for dynamic simulation of induction machines

Abstract

The new generation of electric locomotives is equipped with asynchronous traction motors., When these motors are fed with non-sinusoidal voltage, the skin effect in the rotor bars modifies the behaviour of the traction system. A mathematical model of a squirrel-cage induction motor is presented in this article. It considers skin effect in rotor bars for frequencies up to about 1500 Hz. The main idea is to represent the rotor bars as a lumped network of resistances and inductances. The model is part of a complete simulation program for a full-power main line locomotive.It is used for a more accurate investigation of copper losses and torque pulsations in the motor. Theinvestigations have been conducted at the Royal Institute of Technology, Stockholm, using a simulation language suitable for studying the dynamics of systems.

Parameter Sensitivity and Measurement Error Propagation in Torque Estimation Algorithms for Induction Machines

“…There are several ways to consider this skin effect [13], [14]. Anyhow, owing to the nature of this effect, the size (and shape) of the conductors is of importance, therefore, at least the height of the rotor bars should be known in order to be able to correct the rotor impedance [13], [14]. Such a correction is also provided in the proposal for a new IEC standard for the determination of the quantities of equivalent circuit diagrams.…”

“…However, in order to obtain correct torque estimates, skin effect in the rotor bars and, to a minor extent, temperature corrections should be taken into account. There are several ways to consider this skin effect [13], [14]. Anyhow, owing to the nature of this effect, the size (and shape) of the conductors is of importance, therefore, at least the height of the rotor bars should be known in order to be able to correct the rotor impedance [13], [14].…”

Study on Predicting Induction Motor Characteristics of Alternate QD Model Under Light Loads by Comparing Performance of MTPA Control

“…자속의 포화를 고려한 모델은 참고문헌 [4], [5], [7]- [9]에서 언급되었으며, 회전자의 표피효과는 참고문헌 [6]- [9]에서 거론되었다. 참고문헌 [9]는 자속 포화, 회전자의 표피효과 등을 포함하고 있지만, 회전자 회로의 고주파수에 대한 응답특성이 빠져있다.…”

An induction machine model for predicting inverter-machine interaction

“…A major research area has been in incorporating main-axis magnetic saturation into the model [6]- [15]. Another area of improvement has been the incorporation of the deep-bar effect specific to squirrel cage rotors [16]- [18], which in effect recognizes the large rotor bars as distributed-parameter systems. In [19]- [21], both deep-bar and main-axis saturation are accounted for.…”