Development Of Simulation Software Of Wave Process In Power Transformer Winding

The wave process calculation of power transformer winding is very importantpart in transformer design, main task is to assess the insulation of the transformerlongitudinal insulation under impulse voltage. In this paper, on the basis ofsummarizing the relevant literature, using the finite element software ANSYS APDLprogram language mixed with the MATLAB program language, to develop a newwave process simulation software.In terms of equivalent circuit, this paper established the equivalent circuit modelof the high voltage winding under the condition of ignoring the impedance. Thismodel is composed of longitudinal capacitance, ground capacitance and inductance.And then to solve the equivalent circuit, deduces the node potential formula andpotential gradient calculation formula.In terms of capacity calculation, this paper contrasts and demonstrates thereasons of the analytical method and the finite element method to solve the error ofcapacitance. And then consider that the finite element method to solve capacitortakes into account the factors of edge effect, so the results of the calculation moreaccurate than analytical method. This paper uses the ANSYS finite element softwareto calculate the turn-to-turn capacitance, disk-to-disk capacitance and groundcapacitance.In terms of the wave process simulation software development, this paper usesthe finite element software ANSYS APDL program language mixed with theMATLAB program language. This paper uses APDL program language to write theprogram of calculating capacitance for the first time incase MATLAB invokes them;afterwards, uses MATLAB GUI tool to make the interface of the software; at last,uses MATLAB programming language to write the wave process calculationprogram to complete the development of simulation software.Input the parameters of the wave process through the software interface, thesoftware would invoke ANSYS finite element software to calculation capacitance, and then transmit the result back to the MATLAB program through thecommunication between ANSYS and MATLAB, and at last completes the waveprocess calculation.Finally, in this paper, uses the software to calculate the wave process of thepower transformer high voltage winding with the SFSZ11-63000/220type andSZ9-50000/110type. And gets the initial potential distribution, the initial potentialgradient and impulse response of each disk, in the condition of the high voltagewinding be impacted by standard lightning impact full wave shock wave andlightning impact chopped wave.