Voltage Distribution In Windings Research Articles

Study on voltage distribution in windings of an inverter-fed traction motor

Voltage distribution in windings is important for inverter-fed traction motors. The analysis on voltage distribution characteristics is significant to the study of insulation failure mechanisms and structure design. First, a distribution parameter model has been developed according to the winding structure of an inverter-fed traction motor. Based on the model, finite element differential method was employed to determine voltage distribution characteristics. Simulation results were compared with actual voltage distribution. Moreover, the influence of pulse rise time and cable was discussed. The results show that the shorter the pulse rise time is, the more uneven the voltage distribution is. In addition, cable length has little influence on voltage distribution characteristics. However, the amplitude of voltage would also increase by 40% in coils and turns.

Experimental validation of a computer model simulating an impulse voltage distribution in HV transformer windings

A number of computer models have been recently proposed for simulation of the impulse voltage distribution in the winding of power transformers. Some of these models can predict the winding behavior at high frequencies, some other were developed as a practical tool for designers of lower voltage transformers. The time and expenditure put in development of these models should be balanced by a similar effort to check the model validity. Such checks consist of a comparison of the predicted voltages to the actually measured ones. With the advent of high resolution, fast digital recorders and signal processing techniques, this validation can be performed to a much higher accuracy and completeness than the conventional comparison of analog oscillograms to simulated graphs. The paper presents such a validation technique applied to a computer model of a transformer winding.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Determination of the impulse voltage distribution in windings of large power transformers

This paper presents an analytical method for obtaining the transient overvoltage response of large multiwinding power transformers. The windings of the transformer are divided into a finite number of segments and represented in the form of an electrical network containing the self and mutual inductances, series, ground and interwinding capacitances. A mathematical model representing the above network is analysed to calculate the eigenvalues and eigenvectors. Based on this, the temporal and spatial variations of voltage in the windings are computed when subjected to either a unit step or any surge voltage of given waveshape. For various types of transformers the results have been computed and compared with measured values.