Three-Winding Transformer
The high power Three-Winding transformer applies new type insulating structure and makes short-circuit resistance strong. The iron core is made of high-quality cold-rolled silicon-steel plate. High-voltage winding group is made up of high-quality oxygen-free copper lines and it adopts multilayered drum type structure. All fasteners have been processed with special treatment to prevent them from loosening.
1)The high-voltage (HV) coil adopts an interleaved-continuous structure to improve the voltage characteristics under impact voltage and make voltage evenly distributed. All stays and pads are chamfered to keep highly reliable insulation.
2) In the transformer winding there is a zigzag oil guide structure so as to fully cool all areas inside the winding, lower the temperature rise of the winding and the hot points of the winding and prolong the service life of insulation. The HV and MV regulation system are independently provided with voltage-regulating winding to balance the ampere turn of each winding, effectively lower the axial electrodynamic force generated at short-circuit of transformer and improve abrupt short-circuit withstanding capacity.
3) The winding adopts radial "0" margin designed, between the core and the paper sleeve of LV winding, and between the LV, HV, voltage-regulating windings, as well as before insertion of stays and shroud plate they are fully dried and tightly matched to ensure extremely good compactness and concentricity of the entire winding.