Converter transformer for inhibiting DC magnetic biasing

Abstract

The invention relates to a method for realizing a converter transformer for inhibiting DC magnetic biasing. In the method, joint widths among core laminations of the transformer are increased, and the method specifically comprises the following steps of: calculating the widths and heights of the laminations of each level according to the preserved joint width between every two laminations, the section of a core, the width between every two columns and the height of a window; cutting the laminations according to the calculated widths and heights of the laminations; laminating the laminations in a way of laminating every two laminations according to the sequence of the levels, and alternately arranging the laminations on a core frame according to the levels; and tightening the laminations of each level after all the laminations are laminated. The method has the advantages of effectively reducing the damage of DC magnetic biasing current to the transformer and further reducing the influence and damage of the transformer influenced by the DC magnetic biasing current on / to a power system.

Description

technical field [0001] The invention relates to the technical field of transformer manufacturing, in particular to a converter transformer used for suppressing DC bias under various capacities. Background technique [0002] Due to factors such as DC transmission network and geomagnetic changes, the ground potential of the neutral point of the transformer rises, causing the DC bias current to enter the transformer coil through the neutral point, resulting in half-wave saturation of the transformer excitation current. [0003] In the absence of DC, the no-load current of the transformer winding works in the linear segment of the core magnetization curve Φ(t). At this time, the excitation current is basically a sinusoidal waveform or a symmetrical state approximately sinusoidal, such as figure 1 Shown by the solid line in (c). However, under the action of DC current bias, the no-load excitation current shifts on the core magnetization curve Φ(t), and the half-wave of it works ...

AI Technical Summary

Problems solved by technology

[0004] Due to the half-wave saturation of the iron core, a large number of supersaturated flux linkages are closed outside the iron core, and the excitation current is severely distorted. The transformer itself will experience increased no-load loss, increased vibration, and increased noise. It will also cause transformer cores, metal structural parts, A series of hazards such as local overheating of the fuel tank, and even damage to the insulation, which will endanger the power system in severe cases and even cause the collapse of the power grid

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