JPH084051B2 - Insulating oil Direct circulation type abutting iron core type oil filled transformer or abutting iron core type oil filled reactor - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an insulating oil direct circulation type abutting iron core type oil-filled transformer or an abutting iron core type oil-filled reactor, and more specifically, an abutting iron core type oil-filled transformer or an impulse type. The present invention relates to an insulating oil direct circulation type device that improves the heat exchange efficiency by reducing the temperature difference between the conductor maximum temperature of a synthetic iron core type oil-filled reactor and the heat exchanger oil temperature.

Conventionally generally used oil-filled transformers and reactors, the equipment body is electrically insulated by insulating oil,
Further, this device body is cooled by using insulating oil as a heat medium. Thus, cooling methods include self-cooling cooling with insulating oil and forced cooling with insulating oil. In self-cooling type cooling, the equipment tank and heat exchanger are directly connected, and the insulating oil circulates between them due to the temperature difference, and the winding conductor covered with the insulator is in the equipment tank that gently flows by natural convection. It is only immersed in the insulating oil of. Therefore, the thermal resistance from the winding conductor to the insulating oil is large, and the heat exchange efficiency is extremely low. Further, the forced circulation type cooling is only one in which a circulation pump is provided between the equipment tank and the heat exchanger in the self-cooling type cooling, and the insulating oil is forcedly circulated beyond the temperature difference, Although the flow of insulating oil is fast, after all it becomes a heat transfer through the interposition of an insulator, and the thermal resistance from the winding conductor to the insulating oil is still large, and it is difficult to cool the entire winding uniformly. .

The inventor of the present application, as a result of earnest research to solve such a problem, hollows the winding conductor of the device body and forcibly circulates the insulating oil in the hollow portion of this conductor High-speed oil flows without any interposition, heat exchange efficiency is also improved, and insulating oil passes through the entire length from one end to the other end of the conductor, which makes it possible to uniformly cool the entire area. However, based on this finding, in an abutting iron core type oil-filled transformer or an abutting iron core type oil-filled reactor having a device body composed of a hollow conductor and an abutting iron core of the present invention, a winding consisting of the hollow conductor of the device body. One end of is connected to one electrical terminal and opens into the equipment tank,
The equipment tank communicates with the inlet of the heat exchanger, the other end of the winding made of the hollow conductor of the equipment body is connected to the other electric terminal and also communicates with the insulating pipe, and communicates with the outlet of the heat exchanger via the pump. Insulation oil direct circulation type abutting iron core type oil-filled transformer or abutting iron core type oil-filling reactor so that the insulating oil can be circulated to the equipment tank, heat exchanger, pump, insulating pipe and hollow conductor by a pump. Came to invent.

Here, the coil conductor of the device main body is electrically insulated by the insulating paper, the insulating paper is interposed between the coil conductors, and the insulating oil flows between the coil conductors. It is assumed to have.

Coil conductor upper limit temperature> Coil conductor average temperature> Insulating oil temperature in contact with coil conductor> Average insulating oil temperature> Insulating oil temperature of heat exchanger Generally, the heat quantity Q radiated by a heat exchanger is calculated by the following equation (1) ).

Q = KS θ _A (1) where K heat exchange constant S heat radiating area of heat exchanger θ _A temperature difference between insulating oil temperature and ambient temperature of heat exchanger In equation (1), the temperature difference θ _A is large. In this case, the amount Q of heat radiated is naturally large.

_Let M _{S be} the allowable upper limit temperature of the insulators classified by insulation type, and M be the maximum temperature of the conductor in the actual usage state.
The temperature difference between M and the insulating oil of the heat exchanger is θ _C , and the ambient temperature is θ
_{When set to 0} , the following equation (2) is obtained.

θ ₀ + θ _A + θ _C = M ≦ M _S (2) In the formula (2), M _S is a standard value and is therefore a constant value. Although M changes depending on the usage conditions, even if M and the ambient temperature θ _C change, it is necessary to increase θ _A , that is, to efficiently transfer the heat of the conductor to the insulating oil to improve the efficiency of the transformer or reactor. It is nothing more than that.

Incidentally, in general, electrical equipment has a classification method called insulation type according to the heat resistant temperature of the insulator used for the conductive part,
The allowable upper limit temperature is specified for the insulator, and the temperature rise limit is also specified for the equipment that uses the insulator. Also in the oil-filled transformer of the present invention, the maximum allowable temperature of the winding (coil conductor) is specified to be 95 ° C.

Although the conductor temperature changes depending on the current value, the temperature rise at the rated current (current determined by the capacity performance of the equipment) need only be 95 ° C or less, which is the specified temperature. The value is calculated.

Embodiment In FIG. 1, an equipment body 2 composed of an insulated hollow conductor 5 and an abutting iron core shown in FIG. 2 is installed inside an equipment tank 1. The device body 2 is connected to an outlet of a heat exchanger 3 separate from the device tank 1 via a pump 4 by a hollow insulating pipe 6. The insulating oil reaches the insulating pipe 6 from the equipment tank 1 via the heat exchanger 3, and in the middle of this, the oil directly passes from the heat exchanger 3 to the hollow conductor 5 of the equipment main body 2 by the pump 4, Oil is discharged from the conductor 5 to the equipment tank 1.

In other words, in the present invention, the oil in the equipment tank is pumped and circulated through the hollow conductor of the transformer via the pump, takes heat from the hollow conductor, and is then discharged again into the equipment tank.

By the way, the winding temperature of this type of conventional oil-filled transformer is about 60 ℃ on average, and the low cooling effect is usually about 90 ℃.
There is uneven temperature inside the device.

On the other hand, in the present invention, since the conductor of the winding is hollow and the insulating oil is circulated in the hollow portion, there is no inclusion such as an insulating material, and there is direct contact to directly transfer heat. And a large flow velocity, there is no local temperature rise, there is no temperature unevenness inside the equipment, and the temperature difference θ _C
Becomes a very small value, and therefore the value of θ _A becomes large, and the cooling is most efficiently performed.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of an embodiment of an insulating oil direct circulation type abutting iron core type oil-filled transformer or an abutting iron core type oil-filled reactor of the present invention. FIG. 2 is a schematic explanatory diagram of a device body in the configuration of the embodiment of FIG. In the figure, 1 ... Equipment tank 2 ... Equipment body 3 ... Heat exchanger 4 ... Bomb 5 ... Hollow conductor 6 ... Insulation pipe

Claims (1)

[Claims] Claim: What is claimed is: 1. An insulating oil direct circulation abutment iron core oil-filled transformer or an abutment iron core oil-filled reactor having a device body composed of a hollow conductor and an abutting iron core. Has one end connected to one electrical terminal and opened into the equipment tank, the equipment tank communicates with the inlet of the heat exchanger, and the other end of the winding consisting of the hollow conductor of the equipment body is connected to the other electrical terminal. Insulation that communicates with the insulation pipe and communicates with the outlet of the heat exchanger through the pump, and allows the insulating oil to be circulated by the pump to the equipment tank, the heat exchanger, the pump, the insulation pipe and the hollow conductor. Oil direct circulation type impact iron core type oil filled transformer or impact iron core type oil filled reactor.