Original scientific paper
THE NUMERICAL CALCULATION OF LOW FREQUENCY ELECTROMAGNETIC TRANSIENT PHENOMENA IN POWER TRANSFORMERS
A. Tokić
I. Uglešić
Abstract
In this article, a transformer model is presented that is applicable to low frequency electromagnetic transient phenomena of up to 1 kHz. An example of the energization of a no-load transformer is analyzed. A simplified analytical approach is presented first. Due to the limitations of this approach, a numerical approach is introduced for the solution of the stiff differential equations that describe the transient phenomena. In both cases, algorithms have been developed for generating the waveforms of the state variables. The results of both algorithms are compared to the results of the MATLAB/Simulink/Power System Blockset for the analysis of electromagnetic transient phenomena in electrical energy systems. Developed algorithm with the introduced numerical approach can be used successfully in other low frequency transient phenomena where the main subject of analysis is the nonlinear character of the transformer: ferroresonance, load switch-off, transformer faults etc. Finally, a comparison is made between the measured and simulated inrush currents of a three-phase three-legged transformer.
Keywords
implicit trapezoidal rule; magnetization curve; stiff differential equations, transformer energization
Hrčak ID:
18690
URI
Publication date:
30.10.2007.
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