JPS59119709A - Electric machine - Google Patents

Abstract

PURPOSE:To keep the condition of an electric machine, which is cooled by a liquid coolant, at its initial condition for a long period by a method wherein a removing member of the decomposed substance of the coolant, which is composed of a moisture absorptive resin and an inorganic adsorbing material, and electromagnetic valves, which operate interlocking with a detector which detects the deterioration of the coolant, are provided in the circulation system of the coolant. CONSTITUTION:A heat emitting electric machine 1, such as a transformer or a capacitor, is housed in a case 3 and the gaps are filled with insulating coolant 2 such as Flon. Then a heat exchanger 5 is connected to the case 3 by a pipe 4 and a container 6, in which the element for removing the decomposed substance, and a circulation pump 7 are connected in series with them and the liquid 2 is circulated. The removing member can be such as a moisture absorptive resin, activated carbon, alcoalumina and molecular sheeve. Or, a by-path 10 is provided to the container 6 and the liquid may be introduced through the container 6 or through the by-path 10 in accordance with the operation of electromagnetic valves 8.

Description

[Detailed description of the invention] [Technical field to which the invention pertains] The present invention relates to a detection method for detecting deterioration and decomposition products of a liquid for effectively cooling and insulating electrical equipment under conditions of high temperature and high voltage. An electrical device that is equipped with a detector that detects decomposition products based on this information, and that uses this information to remove decomposition products and moisture, suppress deterioration of the liquid, and maintain it in a stable state for a long period of time. Regarding.

[Prior art and its problems]

Since the main insulation of small voltage transformers is paper, in the early stages, purified insulating oil is filled after removing moisture by heating and degassing for a long time, but there is a problem that residual moisture gets mixed into the oil. be. Furthermore, during operation, insulators and insulating oil in the vicinity decompose due to partial discharge and local heating caused by high voltage, resulting in hydrogen (12).

Methane (GH2), Ethane (C2H6) r Ethylene (C2H4) Acetylene (C2H2) *-Carbon oxide (
Combustible gases such as Co) are generated and dissolved in the insulating oil, accelerating the deterioration of the insulating oil.

However, currently, internal abnormalities are detected by measuring the concentration of hydrogen gas through a gas separation membrane, but if it gradually increases to the limit value, power loss increases depending on the degree of deterioration, so it is not efficient. There is a problem that the value decreases.

Furthermore, when the limit value is reached, the transformer is stopped, internal diagnosis is performed, and all or a certain percentage of the insulating oil is replaced. This leaves room for improvement in terms of efficiency during operation, use of insulating oil, and reliability.

On the other hand, in recent years, the use of fluorocarbon-based refrigerants as a cooling medium has increased, from cooling small electronic components to automotive power semiconductor power conversion equipment, due to their favorable properties such as nonflammability and high heat transfer coefficient. ing.

The mainly used refrigerant is Freon R-113 (CC1F
2-CCII 2F), but others are also used singly or in a mixed state depending on the boiling point.

However, this refrigerant has a high decomposition temperature in its purified state, but when metal materials coexist with organic materials, the decomposition temperature is high.
Decomposition proceeds even at or below 'o'.

As a result, it reacts with C7, F ions, or trace amounts of dissolved water, and HCI, carbon dioxide, and the like are generated as decomposition products. These acid components corrode the metals of the structural materials and may significantly reduce the reliability of the equipment.

[Purpose of the invention]

The present invention improves the above-mentioned drawbacks of conventional electrical equipment by installing a mechanism in the circulation path of the cooling insulator to adsorb and remove moisture and decomposition products contained in the cooling insulator, thereby improving the efficiency of these equipment. The purpose is to provide a mechanism that maintains a state close to the initial state over a long period of time and provides high reliability.

[Summary of the invention]

Liquids that serve both as cooling and insulation, such as insulating oil and chlorofluorocarbons, can be kept in good condition by removing moisture and decomposition products. However, there are a number of adsorbents for removing decomposed products, such as various activated carbons and molecular sieves, but the adsorption amount of water sieves is very small and insufficient.

Recently, some of the water-absorbent resins on the market absorb 300 to 800 times their own weight of water through a chemical reaction. It has been found that removal with an adsorbent effectively keeps the liquid clean. Since this water-absorbing resin has a phenomenon in which it expands in volume or gels when it reacts with moisture, it is necessary to mix it with a nonwoven fabric or a porous substance. Therefore, the liquid inflow path first removes moisture by passing through the water-absorbing resin,
Next, a greater cleaning effect can be obtained by flowing to an adsorbent that adsorbs decomposition products, but the effect is also great even when both components are mixed.

The device configured as described above is installed as one element in the circulation path of the device. This element is installed in a removable manner so that liquid can flow through the pulp as needed, and after sufficient moisture and decomposition products have been adsorbed, the element can be replaced without stopping the equipment. A detector is installed to measure the deterioration of the liquid, and by linking this with the pulp, the pulp is immediately opened and the liquid is cleaned when deterioration occurs. Normally, passing through this element would add pressure loss, etc., so avoid this and only allow the water to flow when it exceeds a set value that would result in decomposition products.

By doing this, initial contamination and moisture from the liquid due to the initial running-in operation are removed, and the increase in decomposition products is constantly removed during operation, so that the insulation and cooling properties of the liquid are maintained. The effect of installing this system is very large, as it can prevent increases in loss due to liquid contamination, allow the equipment to fully perform its functions, and suppress deterioration in reliability due to corrosion and the like.

〔Effect of the invention〕

Dust, dirt, moisture, and other impurities contained inside the machine can be sufficiently removed during the initial break-in operation before the start of operation, and the condition of the equipment at the start of operation is extremely stable. Since dissolved decomposition products and water can always be kept at a low level, troubles caused by these can be suppressed, and at the same time, losses such as leakage current dielectric loss can be greatly suppressed.

On the other hand, components that promote corrosion and deterioration caused by decomposition products and moisture can be suppressed to low concentrations, allowing equipment to operate stably over long periods of time and significantly improving reliability.

[Embodiments of the invention]

One embodiment of the present invention will be described using the drawings. 1 in Figure 1
is a main body of a heat-generating electric device such as a transformer or a capacitor, and a space 2 in a casing 3 surrounding the main body is filled with an insulating cooling liquid such as fluorocarbon to cool the main body of the electric device. A heat exchanger is connected to the casing 3 via a pipe 4, and is further piped to the casing via a container 6 containing the component element for removing decomposition products of the present invention and a circulation pump 7 to supply cooling liquid. A circulating flow path is formed.

As a material for removing decomposed products, a water-absorbing resin such as Aratup (product name, manufactured by Arayo Kagaku KK) and an inorganic adsorbent such as activated carbon, alcoalumina, or Molecular Sheep 4A can be mixed together or separately. It is used filled in a container.

An experimental example showing the effect of removing decomposition products is shown below.

(0.3 g of a water-absorbing resin (Alaboop, Arayo Kagaku Co., Ltd.) was added to 100 ml of υ insulation oil (JIS-2 oil) and stirred.

(2) Freon R-113 (CC112F-CCIF2)
Add 0.3 g of water absorbent resin (same as above) to 100 ml and stir Initial value (moisture content): 15.0 ppm 1 hour
After... L, Q n Below (3) Freon R
, 1130 decomposition product f(Cl gas) was adsorbed with an inorganic adsorbent.

Table In the above embodiment, an example was shown in which the decomposition product removal member element was always connected to the circulation path, but in the present invention, the second
As shown in the figure, a bypass 10 for the element 6 may be provided, and the cooling medium may be passed through either the element or the bypass using pulp or electromagnetic pulp 8, or the element may be mounted on a 7 flange 9. is removable,
It can also facilitate element replacement.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram for explaining the electrical equipment of the present invention;
FIG. 2 is a schematic diagram showing another arrangement example of the member element for removing decomposition products of the present invention. DESCRIPTION OF SYMBOLS 1... Electric equipment main body, 5... Heat exchanger, 6... Decomposition product removal member, 7... Circulation pump, 8... Pulp, 9... Flange.

Claims (4)

[Claims] (1) An electrical device that is cooled using a liquid refrigerant, characterized in that a member for removing decomposed products of the cooling liquid, which is made of a water-absorbing resin and an inorganic adsorbent, is disposed in the circulation path of the cooling liquid. (2) The electric device according to claim 1, wherein the decomposition product removal member is removably disposed. (3) The electrical device as set forth in claim 1, wherein the decomposed product removing member is disposed through the pulp. (4) The electric device according to claim 3, wherein the pulp is an electromagnetic pulp that moves once with a detector that detects deterioration of the cooling liquid.