JPS60768B2 - Cooling device for substation equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention reduces the heat loss generated by the transformer and actuator by transferring heat from oil to an intermediate cooling medium such as water or chlorofluorocarbons using a heat exchanger attached specifically for each device. The present invention relates to a cooling system for substation equipment that cools equipment using a dry or wet cooling tower.

In the case of the condition that "the transformer is operated at a constant load factor P throughout the year, or the highest load factor is P throughout the year", the winding temperature is Even if the cooler is partially stopped and the oil temperature is increased so that the oil temperature does not exceed the maximum winding temperature during operation, the predetermined service life will not be impaired.

In other words, if the highest points of winding and oil temperature in 100% continuous operation are Qc and Qo, respectively, then the allowable oil temperature at load factor P% is Qc without changing the oil circulation amount.
-(Qc-Qo)・P1・6~2, which is 1 under the above conditions
It is possible to operate with the oil temperature raised by the amount that reduces the temperature difference between the winding and the oil compared to when it is 00%.If this idea is applied, if the load factor of the transformer is under the above conditions throughout the year, the load The lower the rate, the higher the oil temperature may be operated, thereby reducing the capacity of the cooler beyond the reduction in heat loss generated. On the other hand, when a reactor is connected to a power system, the heat loss generated and the temperature rise of the winding and oil are constant, so the temperature difference between the winding and oil is always constant, so the same concept as that of a transformer should be adopted. I can't. Therefore, when the transformer and IJ atator oil are cooled in a cooling tower via a common intermediate cooling medium, the temperature of the intermediate cooling medium is limited on the reactor side, and must be set to a value with some margin on the transformer side. In other words, by using a cooling tower with dual ratings, such as evaporative cooling when the load is high and forced air cooling when the load is low, and operating it under wind when the load factor of the transformer is P, the above-mentioned Oil temperature Qc
- (Qc - Qo) When the temperature of the intermediate cooling medium becomes Qwp, when the temperature of the intermediate cooling medium becomes Qwp, when the reactor is cooled by this intermediate cooling medium, the oil temperature of the IJ actor becomes higher than the temperature of the transformer. The temperature difference between the wire and the oil is also {(
Qc-Qo)(1-P1・6~2)}, which will reduce the lifespan. Therefore, when operating the reactor and transformer at the same time, check the oil temperature difference between the transformer and IJ actor and It is only possible to operate at a load rate that lowers the temperature of the intermediate cooling medium by an amount corresponding to the difference between the temperature of the winding and the oil and that of the IJ actor {(Qc-Qo) (1-P1・6~3)}. Can not. Conventionally, this type of apparatus has been constructed as shown in FIG.

In the figure, 1 and 2 are attached oil-filled transformers and oil-filled actors, and LA or IC is attached to the oil-filled transformer 1, and the oil in the oil-filled transformer 1 and an intermediate cooling medium such as water or fluorocarbon are used. Heat exchangers 2a and 2b are attached to the oil-filled actor 2 and are heat exchangers that exchange heat between the oil in the oil-filled actor 2 and the intermediate cooling medium; 3 is a heat exchanger for exchanging heat between the two above-mentioned A cooling tower is generally installed on a rooftop and cools an intermediate cooling medium that undergoes heat exchange with oil through vessels la to 2b and is sent all at once through a common pipe 4. As mentioned above, in the conventional system, the heat loss generated from the oil-filled transformer 1 and the oil-filled actuator 2 is transferred to the cooling tower 3 through a common intermediate cooling medium.
Therefore, when using a dual-rated cooling tower 3, such as evaporative cooling at high loads and forced air cooling at low loads, the conditions for operating with forced air cooling are: The permissible load factor of the oil-immersed transformer 1 has been kept low because it is limited by the oil temperature of the transformer 2.

The present invention has been made in order to eliminate the drawbacks of the above-mentioned conventional apparatus, and a third heat exchanger is attached to the intermediate cooling medium side circuit inlet of the heat exchanger attached to the oil-filled actor. By cooling only the intermediate cooling medium sent to the transformer, the cooling tower shutdown ratio can be increased relative to the transformer load ratio, or the transformer permissible load ratio can be increased relative to the cooling tower shutdown ratio. The purpose is to increase the transformer load factor that allows forced air cooling operation when the cooling tower is dual rated for evaporative cooling and forced air cooling. It provides a cooling device for transformer equipment that reduces the need for auxiliary equipment changes and extends the life of the equipment.

An embodiment of the present invention will be presented below with reference to the drawings.

In FIG. 2, an oil-filled transformer 1, an oil-filled actuator 2, a cooling tower 3, heat exchangers la to 2b, and a common pipe 4 are the same as those shown in FIG. 1. 5 indicates heat exchangers 2a and 2b. This is a third heat exchanger, such as a heat pump, provided at the inlet of the intermediate cooling medium side circuit.

According to one embodiment of the present invention configured in this manner, the temperature of the intermediate cooling medium sent to the heat exchangers 2a and 2b by the third heat exchanger 5 is controlled by the oil-filled transformer 1 and the oil-filled actuator 2. The difference between the oil temperature difference between the winding temperature of the oil-filled transformer 1 and the oil temperature and that of the oil-filled actuator 2 is reduced. As described above, according to the present invention, the cooling tower shutdown ratio is increased relative to the transformer load ratio, or the transformer allowable load ratio is increased relative to the cooling tower shutdown ratio, compared to the conventional technology. If the cooling tower is dual rated, such as evaporative cooling and forced air cooling,
It is possible to increase the load factor of transformers that can be operated with forced air cooling, and this has great effects such as reducing water consumption, reducing the need to replace auxiliary equipment during operation, and extending the life of equipment. .

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a conventional cooling device for substation equipment, and FIG. 2 is a block diagram showing the configuration of a cooling device for substation equipment in an embodiment of the present invention. In the figure, 1 is a fine-injection transformer, 2 is an oil-filled actor, and l
A to lc are first heat exchangers, 2a and 2b are second heat exchangers, 3 is a cooling tower, and 5 is a third heat exchanger. Figure 1 Figure 2

Claims (1)

[Scope of Claims] 1. An oil-filled transformer and an oil-filled actor that are installed together, and first and second heat sources that are attached to the above-mentioned devices and exchange heat between the oil in the above-mentioned devices and an intermediate cooling medium. In the device comprising an exchanger and a cooling tower for cooling the intermediate cooling medium that has undergone heat exchange, a third heat exchanger is attached to the intermediate cooling medium side circuit inlet of the second heat exchanger. A cooling device for substation equipment featuring: 2. The cooling device for power substation equipment according to claim 1, wherein the intermediate cooling medium is water. 3. The cooling device for power substation equipment according to claim 1 or 2, wherein the eighth heat exchanger is a heat pump.