If the humidity of the space where electrical equipment is located is high, the insulation of electrical equipment will gradually decrease, which will lead to leakage and other situations, which will bring hidden dangers to people's life safety. This paper analyzes the factors leading to the quality problems of electrical equipment from three aspects of humidity, temperature and medium composition, and based on this, advances some optimized countermeasures for strengthening the moistureproof of electrical equipment.

Electrical equipment; Moisture-proof; the key to the question

From the point of view of electrical equipment itself, if the humidity in the space is relatively high, the insulation of electrical equipment will gradually decrease, leading to leakage and other situations, which will bring hidden dangers to people's life safety. Coupled with the relatively high humidity, the internal components of electrical equipment are corroded and rusted, which leads to low efficiency of equipment operation, operation accidents and economic losses to enterprises. It can be seen that it is very necessary to do a good job in moistureproof of electrical equipment.

1, the significance of electrical equipment moistureproof

For electrical equipment, metal loss is mainly divided into four types, the first is corrosion; The second is fatigue; The third is friction; The fourth is wear and tear. These will have a direct impact on the operation cycle of electrical equipment. Among them, the proportion of electrical equipment damage caused by humidity is high. At present, the exploration and design of conventional electrical equipment have reached relevant standards, and a lot of work experience has been accumulated in production and application, which has met the application of electrical equipment in conventional environment [1]. However, there is relatively little research on the application of electrical equipment in special environment. In the early stage, people hope to use related facilities for ventilation and dehumidification to ensure that electrical equipment is always in a relatively dry environment. Practice shows that it is relatively difficult to provide an ideal operating environment for electrical equipment, and it is difficult to meet the development needs of a conservation-oriented society by using air-conditioning facilities to remove moisture and other resources, and the electricity bill is relatively large. Therefore, it is of great practical significance to discuss the moistureproof work of electrical equipment.

2. The main factors causing quality problems of electrical equipment.

2. 1 humidity

Usually, the amount of water vapor in the air is humidity. The higher the water content, the greater the air humidity. Generally, the degree of humidity is expressed by the amount of water vapor in the air 1kg, as shown in Table 1. At the same temperature, the water vapor content in the air has a certain degree. When the temperature rises, the water vapor content in the air will reach the saturation standard. When the temperature reaches a certain standard, the ratio between the water vapor content in the air and the saturated water vapor can be regarded as the corresponding humidity. When the water vapor content in the air increases and reaches or exceeds saturation, water dew will appear. Assuming that air saturated with water vapor is not cooled, mist-like moisture will be formed in the air. In this case, moisture will adhere to electrical equipment, and in the long run, electrical equipment will be corroded to varying degrees, which will affect the operation of electrical equipment.

2.2 temperature

The temperature and humidity in the electrical equipment cabinet will change with time. When the relative humidity of the surrounding environment where electrical equipment is stored is less than its critical value, the temperature will change the corrosion efficiency. When the temperature rises here, the electrical equipment will not be corroded because of the dry environment. When the relative humidity exceeds the critical humidity of electrical equipment, the change of temperature will have a certain impact. At this time, the corrosion efficiency will increase twice for every ten degrees Celsius increase in temperature [2].

2.3 medium composition

The air contains a lot of auxiliary gases [1], such as sulfur dioxide and carbon dioxide. These substances will promote the corrosion efficiency of electrical equipment to a certain extent. Among them, sulfur dioxide will bring serious corrosion to electrical equipment. When the concentration of sulfur dioxide in the air is higher than 0.0 1%, the critical humidity of electrical equipment will gradually decrease from 70% to 50%. According to the test results of atmospheric conditions, the corrosion efficiency of electrical equipment is often directly related to the content of sulfur dioxide in the air.

3, strengthen the optimization countermeasures of electrical equipment moistureproof.

3. 1 Conventional moisture-proof methods

Based on the principle of material corrosion and the control of environmental water content, when the relative humidity in the environment is controlled within 50%, the storage safety of electrical equipment can be guaranteed [3]. Under wet conditions, the safety protection function of electrical equipment in the distribution cabinet is moisture-proof. In general, there are five conventional electrical moisture-proof methods.

3. 1. 1 isolation method seals electrical equipment so that moisture cannot enter the electrical equipment [1]. For example, set up isolation barriers, independently set up storage space for electrical equipment, and install sealed cabinets.

3. 1.2 exhaust method will exhaust the moisture in electrical equipment in time, such as installing induced draft fan or setting moisture exhaust hole.

3. 1.3 sealing method In order to prevent moisture from entering electrical equipment, all channels in the storage place of electrical equipment can be blocked to prevent moisture from entering electrical equipment. For example, holes are filled with plastic sheets and sealed with rubber sheets.

3. 1.4 absorption method uses many materials with moisture absorption function to absorb the moisture in the storage space of electrical equipment. For example, a large amount of hygroscopic agent is placed in electrical equipment, or a large amount of hygroscopic material is placed in the environment where electrical equipment is located.

3. 1.5 heating drying method removes moisture from electrical equipment by heating. For example, install a heating bulb to remove moisture from electrical equipment.

3.2 moistureproof scheme

Usually, electrical equipment will be built in the power distribution cabinet, so the anti-corrosion work of the cabinet should be done well. Because the box body of the distribution cabinet is in direct contact with the humid environment, the probability of corrosion is relatively high, so it is necessary to carry out corresponding moisture-proof countermeasures for the box body. When the inside of the distribution cabinet is sealed, a certain amount of desiccant should be placed in it to facilitate the absorption of moisture in the cabinet and create a dry operating environment for the electrical equipment inside the distribution cabinet [2]. If there are intermittent working conditions, it is necessary to install corresponding internal and external differential pressure protection countermeasures in the power distribution cabinet. When the electrical distribution cabinet is changed from the previous stop operation to the working operation, or in a humid environment, due to the large temperature difference between day and night, there is a certain pressure difference inside and outside the sealed distribution cabinet. Assuming that scientific treatment is not carried out, the seal of the distribution cabinet will age due to the influence of pressure [4]. This phenomenon can be avoided by setting differential pressure protection countermeasures, and the specific scheme is as follows:

1) electrical equipment should be placed on the rack, not directly on the ground.

2) If the humidity is high, buy a special electrical moisture-proof dehumidifier and use some moisture-proof agent at the bottom.

3) Pay attention to ventilation. If there is no natural wind, use a fan for forced ventilation. If the humidity is too high in the morning and evening, it is necessary to close the doors and windows and ventilate when the humidity is low during the day.

4) Use preservatives and spray insulating paint on the key parts that can be sealed. It can also be sealed as a whole if necessary. 5) Where the corrosion and humidity are too serious, the computer room should be built upstairs as far as possible.

4. Concluding remarks

In short, long-term operation of electrical equipment in humid environment will have a direct impact on its electrical performance and stability [5], leading to electrical failure. Only by doing well the moistureproof work of electrical equipment can the faults be fundamentally reduced. Therefore, strengthening the exploration of moisture-proof technology and the design of electrical equipment will play an important role in improving the construction and operation level of electric power enterprises.

refer to

[1], Wu,. Discussion on outdoor wrapped CT moistureproof device [J]. Enterprise technology development, 2016 (5):18-19.

Lin Zhimin, Huang Liang, Cai Hengbin. Study on waterproof and moistureproof technical measures for junction box and mechanism box of electrical equipment [J]. Electric Manufacturing, 20 14(6):88-89.

[3] Liang Chongfeng, Yang Tao. Research on the construction scheme of electrical equipment moistureproof laboratory [J]. Electronic quality, 20 12(8):67-69.

[4] Zhang Yanli, Wang Yuenan, Tian Siqing. Research on Improving the Innovation and Practice Ability of Electrical Engineering Students [J]. Journal of Hunan Vocational College of Posts and Telecommunications, 2010 (1): 48-51.

5. Wu Di. Moisture analysis of electrical equipment [J]. Science and Technology Wind, 20 15(3):79.

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