JPS6242513Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to oil-filled electrical equipment such as transformers and reactors.

Generally, in oil-filled electrical equipment, the heat generated in the electrical equipment body is transferred to insulating oil, and the insulating oil is circulated through a radiator to radiate the heat, thereby cooling the electrical equipment body housed in a case. However, the inside of the winding of an electrical device is hotter than the part that comes into direct contact with the insulating oil, and this heat is not easily transferred to the insulating oil, so the inside of the winding is not cooled sufficiently, and the insulation inside the winding is There were times when things deteriorated due to heat. Therefore, it has been proposed to increase the cooling efficiency of the windings by inserting a heat pipe inside the windings to guide the heat inside the windings to the outside of the case of the electrical device. However, heat pipes are literally pipe-shaped and have a small contact area with the windings.
Because heat transfer from the winding to the heat pipe was not sufficient, the desired heat dissipation effect could not be obtained.

An object of the present invention is to provide an oil-filled electrical device that improves heat transfer to a heat pipe and improves winding cooling efficiency.

The oil-filled electrical equipment of the present invention will be explained in detail below with reference to the illustrated embodiments.

Figures 1 to 3 show an embodiment in which the present invention is applied to an oil-immersed transformer. , 3 are heat sinks attached to the side walls of the case 1. Insulating oil 4 inside case 1
A transformer main body 5 is housed therein, and the ends of the winding 6 are connected to a low voltage bushing 7 and a high voltage bushing 8 attached to the cover 2 by lead wires 9 and 9', respectively. 10 is a heat pipe whose upper end passes through the cover 2 and is led out to the outside of the case 1, and whose lower end is inserted into the winding 6, and a heat dissipation fin F is provided at the end of this heat pipe that protrudes outside the case. installed.

As shown in FIG. 2, the winding 6 consists of a low voltage winding 61 located inside and a high voltage winding 62 concentrically arranged outside the low voltage winding 61. The leg portion of the iron core is inserted into the window portion 61a. Main insulators 63 and 64 are arranged around the outer periphery of the low voltage winding 61 and the inner periphery of the high voltage winding 62, respectively, and are wound to have appropriate thicknesses. A heat pipe 10 is inserted into the gap together with a heat collector 11. More specifically, as shown in FIG. 3, the heat collector 11 consists of a relatively thin strip made of a material with good thermal conductivity such as copper or aluminum arranged around the outer periphery of the low voltage winding 61. The main insulator 63 is formed into a spiral shape with a diameter close to the outer circumferential surface of the main insulator 63, and has a structure that does not form a closed loop. The length of the heat collector 11 in the axial direction is set to be approximately equal to the dimension of the low voltage winding 61 in the winding axis direction. In this embodiment, three heat pipes 10 are provided, and these three heat pipes are provided so that their lower ends 10a are located on the outer peripheral surface near the lower end 11a of the heat collector 11, and are parallel to each other. It is wound along the outer circumferential surface of the heat collector 11 that extends spirally. Each heat pipe 10 is thermally connected to the heat collector 11 by appropriate means such as soldering or brazing. The upper end 10b of the spirally wound portion of each heat pipe 10 is bent so as to rise from the upper end 11b of the heat collector 11 in the direction of the winding axis of the winding. The upper end of the rising portion 10c rising from the upper end of the cover 2
It penetrates and is led out to the outside.

To arrange the heat collector and heat pipe inside the winding, first, a strip is spirally bent to form the heat collector 11, and the heat pipe 10 is attached to the heat collector 11.
After joining, the heat collector 11 is fitted onto the outer peripheral surface of the main insulator 63 outside the low voltage winding 61. After that, the main insulator 6 is placed on the outside of the spiral portion of the heat pipe 10.
4 is wound around the main insulator 64, and a high voltage winding 62 is further wound around the outer periphery of the main insulator 64. By doing so, the heat collector and the spiral portion of the heat pipe can be disposed while maintaining a predetermined insulation strength between the low-voltage winding and the high-voltage winding.

When the temperature of the winding increases due to operation in the oil-filled electrical equipment described above, the heat generated in the winding is transferred to the heat collector 11, and the portion of each heat pipe 10 wound around the heat collector is heated. Ru. As a result, the refrigerant inside the heat pipe 10 is vaporized, and the vaporized refrigerant rises inside the pipe and reaches the upper end of the heat pipe projecting above the cover 2 . The heat carried by the refrigerant in this manner is dissipated to the outside through the radiation fins F and the like provided at the upper end of the heat pipe 10, so that the refrigerant is liquefied again and returns to the lower end of the heat pipe 10. In this way, the coolant circulates, and the heat inside the windings is directly released to the outside of the case, thereby efficiently cooling the windings. In addition, since the heat collector 11 is interposed between the low and high voltage windings, it serves as a cross-contact prevention plate when lightning surges enter the windings, thereby preventing lightning surges from entering the low voltage windings. be able to.
Furthermore, a spiral gap 11A formed in the heat collector 11
Since it acts as an oil channel, it is possible to improve the circulation of insulating oil inside the winding, thereby making it possible to cool the winding more effectively.

In the above embodiment, three heat pipes are provided, but the number of heat pipes is arbitrary. Further, in this embodiment, the axial dimension of the heat collector is approximately equal to the axial dimension of the winding, but the dimensional relationship between the two may be arbitrary. Further, although the heat collector 11 is provided between the high and low voltage windings, it may be provided inside the low voltage windings if necessary. In some cases, a spiral portion of a heat pipe may be joined to the inner circumferential surface of the heat collector 11. In addition, since a low voltage is induced between both ends of the heat pipe wrapped around the heat collector, this can be used as the tertiary winding of a control circuit power supply attached to a transformer, such as a display device. can.

As described above, according to the present invention, the heat pipe is spirally wound along the heat collector and disposed inside the winding, which improves heat transfer from the winding to the heat pipe. This has the advantage of increasing the cooling efficiency of the windings. In particular, in this invention, since the heat collector is spirally shaped, the heat pipe can be wrapped around two turns or more without forming an electrically closed loop, increasing the contact area between the heat pipe and the heat collector. cooling efficiency can be further increased. Further, since an oil passage can be formed by the spiral gap formed in the heat collector, an oil flow can be generated inside the winding, and the cooling effect of the winding due to natural convection of oil can be enhanced.

[Brief explanation of the drawing]

Fig. 1 is a partially sectional front view of an embodiment in which the present invention is applied to an oil-immersed transformer, Fig. 2 is a sectional view of the winding portion of the transformer body shown in Fig. 1, and Fig. 3 FIG. 2 is a perspective view showing an example of a heat collector to which a heat pipe is attached. 1...Case, 2...Cover, 4...Insulating oil,
5... Transformer main body, 6... Winding wire, 10... Heat pipe, 11... Heat collector.

Claims (1)

[Scope of utility model registration request] In an oil-filled electrical device in which a main body of the electrical device is housed in a case along with insulating oil, a heat collector made of a plate-shaped material spirally formed is disposed inside the winding of the main body of the electrical device, and the heat collector is arranged inside the winding of the main body of the electrical device. An oil-filled electrical device characterized in that a heat pipe formed in a spiral shape is joined to a heating body, and one end of the heat pipe is led out to the outside of the case.