When the three-volt weather encounters light rain and sultry heat, it becomes an unavoidable problem in life and an unavoidable problem in the power distribution network. To ensure the safe and reliable operation of the power system, the dehumidification and dehumidification of electrical equipment have become a need for the power industry A big problem. To this end, Cypress takes everyone to focus on the specific measures for moisture and dehumidification of electrical equipment to ensure the safe and stable operation of electrical equipment during the rainy season.　　

Long-term dampness affects the safe operation of electrical equipment

The main metal damage forms of electrical equipment are divided into corrosion, fatigue, friction, and friction, which all have a great impact on the life of the equipment. Among them, the proportion of corrosion damage caused by humidity is large. China has reached or is close to the advanced level at home and abroad in terms of loss prevention of conventional electrical equipment, and has accumulated rich experience in manufacturing, use and maintenance. It has basically met the electrical engineering applications under conventional environments and general use conditions, but it is special for electrical equipment. Applied research under environmental conditions is far from enough.

In particular, electrical equipment exposed to the outdoor environment for a long time should pay more attention to moisture and humidity in the rainy season. The outdoor 35 kV box-type substation is an organically combined high-voltage switchgear, distribution transformer and low-voltage distribution device, which is installed in a movable steel structure box. It is currently widely used in urban network construction and transformation. .

When the rainy season comes and the air in the high-pressure room directly communicates with the outside world, the outdoor high-humidity air directly penetrates into the high-pressure room, and the high-pressure room is usually arranged on the first floor of the substation. After the surface moisture and cable trench moisture are collected, the humidity in the high-pressure room is very high. , Seriously affecting the safe operation of electrical equipment. Therefore, the outdoor 35 kV box-type substation is very important to prevent moisture and humidity.

Safety problems caused by long-term dampness of electrical equipment are not uncommon. An inspector of a power supply company once discovered that a 35 kV high-voltage indoor room was filled with smoke and smelled of burning, and the 35 kV line protection tripped. Then organized professionals and technicians to conduct a comprehensive inspection of the equipment, and found that there was a serious discharge phenomenon in the switch bay busbar and the wall bushing. After testing, the 35 kV bus, the contact box of the car switch and the contact box current transformer have a serious decline in ground insulation, only 3 ~ 5 megohms. Through on-site equipment accident investigation and viewing equipment operation records, relevant professionals have analyzed This insulation breakdown fault eventually occurs due to the internal deterioration of the insulation caused by the equipment being exposed to moisture for a long time.

According to years of experience in electrical environment treatment, when the rainy season is coming, the humidity in the high-pressure room is as high as 95%. Long-term in a high humidity environment, it is easy to cause condensation, and condensation often causes electrical discharge in the high-voltage cabinet, and even causes the switch cabinet to explode. In addition, the electrical equipment in the high-voltage room is operated in a high-humidity and high-temperature environment for a long time, which is very easy to cause serious corrosion of various metal materials, causing the switch cabinet to refuse to move and affecting the normal operation of the knife gate. If the moisture in the 35 kV substation cannot be resolved in time, then a failure caused by moisture may occur at any time.

The rectification effect of outdoor substation moisture-proof measures is remarkable

The factors that affect the corrosion of electrical equipment are more complicated. With the climate and region, the surrounding air temperature, humidity, impurity composition and concentration are very different, and the degree of corrosion of electrical equipment is also different. Normally, the humidity of outdoor box-type substations is concentrated on the following main issues.

First of all, the cable room under the cabinet has no ventilation facilities, and the surrounding walls and floors are not dry for a long time. The enclosure around the bottom of the cabinet is imperfectly sealed. On rainy days, the wall of the cabinet will seep from the outside to the inside and enter the surrounding of the wall under the cable compartment, causing moisture in the bottom of the cabinet. Secondly, because the outside of the cabinet cable is grass, rainwater is stored in the soil, and it will gradually penetrate into the cable indoor wall. The bottom of the four sides of the box body of the high-voltage switch cabinet and the cable room are not fully sealed, and there is air mutual communication between the box body and the cable room. Third, the installation position of the top exhaust fan in the cabinet is unreasonable. When the exhaust fan is turned on, the humid air in the cable room will circulate into the cabinet. When the cold and humid air flows through the electrical equipment, water droplets will form and adhere to the surface of the insulated portion of the electrical equipment. on. Fourth, there is only a small heating plate in the space of the cable outlet of the switch cabinet, and the temperature and humidity controller is installed in front of the cabinet, which fails to truly reflect the temperature and humidity value of the high-voltage equipment space in the cabinet.

In response to the above specific problems, Cypre has conducted a large number of on-site investigations and integrated the on-site conditions of various electrical equipment environments to create a series of effective dehumidification solutions tailored for power companies to solve the problem of moisture in the electrical environment. Cyprix's electrical environment management monitoring system uses big data technology to effectively provide early warning, fault display, and automatic handling of minor accidents in the electrical environment, providing an important guarantee for the safe operation of electrical equipment.

Reasonable moisture-proof measures for substations can avoid the impact of electrical equipment caused by moisture. According to different environmental conditions, measures are taken to rectify the moisture in the cable room, seal the box and the cable room, keep the box and the space inside the switch cabinet dry, and improve the moisture-proof measures. In addition, through technical means, the continuous upgrade of electrical equipment series dehumidification products has become the future trend of avoiding electrical equipment moisture. The SEPRI-CS-NL anti-condensation device of Sepuri series dehumidification products can realize the functions of high humidity warning, fault warning, temperature compensation and fault warning output. SEPRI-CS-DZ overhead dehumidification system meets the design of double-circulation system, the dehumidification speed is faster and stronger; it solves the problem of dehumidification of bus bridges and bus rooms; the original ultrasonic moisture atomization isolation discharge method, split design, to eliminate external impurities Objects into the cabinet. It further guarantees the safe operation of electrical equipment during the rainy season.

In addition, according to the impact of the rainy season on the box-type substation, in addition to installing reasonable dehumidification and dew prevention products, the operation and management personnel of the substation also need to strengthen the standardization of comprehensive moisture protection. Before the rainy season comes, substation operators should take waterproof, moisture-proof and plugging measures for cable trenches and switch cabinet holes in time to ensure the insulation of the cable trench inside and outside the substation high-voltage room and prevent the cable trench moisture from directly invading the high-voltage switchgear.

With the development of smart substations, during the operation of smart substations, the requirements for dehumidification automation are also increasing. Cyprey keeps pace with the times and designs a system solution that is more suitable for the overall monitoring and treatment of substation dehumidification. At present, the overall governance system for the operating environment of Cypre Electric has been widely used in substations of the power grid company and China Southern Power Grid Corporation. After the rectification of the moisture-proof measures in the rainy season of the substation, the humidity of the equipment has been greatly improved, providing an important guarantee for the safe operation of electrical equipment