ZHEJIANG ZHONGYI ELECTRIC POWER TECHNOLOGY CO., LTD

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2022-07-06207 have been browsing

Lightning is a natural disaster. When a lightning disaster occurs, it will cause different degrees of damage to power equipment. Therefore, power supply enterprises will protect power equipment in the process of power transmission operation. The current defense measure is to install lightning arresters in major buildings and equipment to improve the stability of power supply. The principle of the arrester is to use insulation and install insulating materials in the arrester, so that the equipment can resist the damage of lightning when it is subjected to lightning. However, in the actual operation process, there are still many performance problems of the arrester. It is necessary for technicians to discover the operation problems in time during the use process, and propose corresponding targeted measures to improve and perfect the arrester.

 

The power system is an important energy system and has a huge impact on life. In daily life, changes in the weather will cause thunder and lightning weather, which is a great threat to the power system. Therefore, lightning arresters are added to the power system to Reduce the probability of the power system being struck by lightning, thereby ensuring the normal operation of the power system. Corresponding investigations and visits found that the quality and structure of arresters on the market are not the same, and arresters are classified into three types in the market, including silicon carbide arresters, zinc oxide arresters and tubular arresters. Among these three types of arresters, their respective characteristics It is also different. The use of arresters in the power system can also reduce the cost of power system maintenance. When using them, various factors should be considered to observe whether the selected arresters are suitable for the power system or equipment used.

 

1. The protective function and influence of the arrester

 

1.1 Automatic protection system

 

When the arrester is working, it uses the appropriate voltage value to make itself have a certain power-carrying function, and the voltage it carries can be read to protect the system to a certain extent. On the contrary, if the value of the carrying voltage exceeds the bearing range of the arrester, the direct result is If the power system and equipment are damaged, the arrester at this time no longer plays the role of the protection system, and its role is to shunt and limit the voltage. If the power system encounters severe lightning weather in the daily work operation, after the power system is subjected to voltage, the system state at this time will also change. Under certain conditions, it can also stimulate transient overvoltage, transient overvoltage The frequency of the voltage is very strong, and the energy is a fractional or integral multiple of the ordinary power frequency. When using the power system, if the power frequency of the power frequency can be the same as the frequency of the power system, the power frequency power supply at this time will be supplemented. The phenomenon of energy, the function of which is to reduce the voltage of the power system after being struck by lightning, so that the power system can be in a safe working state .

 

The damage of transient overvoltage in the power system is very large, and there is a feature that if the transient voltage passes through the arrester, it is easy to cause damage, and the damaged arrester cannot be restored to work by repairing. And the stability of the power system with the faulty arrester installed is very poor. After analyzing the various problems of the arrester, the arrester was improved and a series gap was added. After adding the series connection, it was found that the operation state of the power system was very stable and very safe.

 

1.2. The arrester affects the power system

 

The operating environment of the arrester is relatively poor. In a relatively poor environment, the accident rate of the arrester is also very high. The strong electric shock current may cause the related components in the arrester to be broken down and damaged. After the damage occurs, various faults in the circuit of the power system occur frequently. After the fault occurs, the stability of the power system will be seriously affected. It is necessary to select a reasonable arrester for various situations. The situation at this time , Zinc oxide arrester should be selected, this arrester can prevent the damage of power system components and improve the stability of power system operation in severe lightning weather .

 

1.3. The lightning arrester has continuous lightning impulse protection capability

 

In severe lightning weather, the arrester plays an important protective role, that is, after the system is subjected to more than two electric shocks, a current-limiting element is installed in the power system, which can limit the voltage and current flowing through the line within a certain period of time. , which can greatly reduce the damage of lightning. The time interval between lightning and lightning is relatively close. In a relatively short time interval, the arrester can cut off the current of the electric shock, but after a power protection, it needs to be buffered. After time, the ability to restore protection continues to provide guarantees for the stable battery life of the power system.

 

2. Problems in the operation of the arrester

2.1. The sealing production is not enough

 

The service life of the arrester is affected by the sealing. If the sealing work of the arrester is in place, the service life of the arrester will be very long. However, the backwardness of the active sealing technology and the unreasonable selection of sealing materials have caused the service life of the arrester. The great influence makes the arrester unable to operate normally in harsh environments. Because the sealing is not done well, a large amount of water vapor and impurities will enter the arrester. These external factors will affect the performance of the arrester. If the seal is not in place, the interior of the arrester will also become wet, and the insulation effect of the arrester will be greatly reduced in the wet state, which can easily lead to the stability of the power system .

 

2.2. The resistor chip is seriously aging

 

In the arrester, because the voltage generated by the electric shock is too large, a resistor sheet is installed in the arrester. The function of the resistor sheet is that when the power system encounters lightning, the huge current of the electric shock can block the current through the arrester and prevent the damage of the arrester, but After being damaged by electric shock and harsh environment for a long time, the aging speed of the resistor sheet is also very fast. After the resistor sheet is severely aged, the protection ability of the power system drops sharply, and the subsequent damage is also huge. It may be It will directly lead to a serious explosion of the arrester, which is extremely dangerous. In order to reduce the aging degree of the resistor sheet, it is necessary to improve the anti-aging performance of the resistor sheet, so that the service life of the arrester can be longer .

 

2.3. Pollution of porcelain sleeves

 

It can be seen in daily life that most arresters are installed outdoors. The outdoor environment is more complicated. Compared with thunderstorm weather, outdoor wind, dust, humidity and other factors have a great impact on arresters. Exposure The arrester in the air is more prone to the aging of the resistance sheet, in which the dust has a great influence on the porcelain sleeve. If a large amount of dust accumulates on the surface of the porcelain sleeve, an insulating layer will be formed on the surface of the porcelain sleeve. The appearance of the insulating layer, It will increase the amount of current passing through, which results in uneven current distribution and reduced sealing effect.

 

3. Specific measures for the application of arresters in power systems

 

3.1. Reasonable design of arrester

 

According to the current arrester market survey, there are many types of arresters, and more relevant investigations need to be carried out in the market. Among the arrester styles collected by the survey, choose the appropriate model. After selecting the corresponding model, you need to understand the sub-types. lightning arrester. Understand the materials, technologies and characteristics used, and after various analysis and comparison, make new improvements to old products, improve the electrical resistance and aging of the arrester, extend the service life, and then choose the appropriate arrester according to the use environment.

 

3.2. Strengthen the management of arresters

 

In the harsh environment, the arrester needs to be inspected and maintained. In this way, the workload will increase. In this case, it is necessary to vigorously recruit relevant practitioners. The increase of the personnel base can improve the distribution of work. Efficiency can shorten the investigation time, so that the problems of the arrester can be found in time, and the arrester with the aging resistance sheet and the pollution of the porcelain sleeve can be checked out, and it can be replaced or repaired to ensure the smooth operation of the power system.

 

3.3. Anti-pollution treatment of porcelain sleeve

 

The porcelain sleeves are polluted in the outdoor environment, and the porcelain sleeves need to be cleaned. However, due to the large number of porcelain sleeves, the cleaning and inspection of a large number of porcelain sleeves will cause great pressure on the inspection work, and more manpower needs to be invested. Material resources, but it is not a long-term solution. To solve the problem, it is necessary to improve the root cause of the problem. One treatment method is to clean the porcelain sleeve, and the other can increase research and development efforts to discover new materials and new substances. Porcelain sleeves are treated accordingly, and the pollution of the porcelain sleeves can be reduced after the treatment, which can ensure the normal use of the arrester.

 

4. Conclusion

 

Surge arrester is an important protection component of the power system. Technicians need to pay special attention to the use of surge arresters. Low-quality surge arresters cannot be used. In view of various problems with surge arresters, technicians need to make adjustments to external unstable factors and their own performance. Comprehensive analysis and research, such as dust, lightning strikes, humidity and other influencing factors in the external environment, should be improved and protected accordingly. In terms of internal performance, it is necessary to research and develop new resistance materials, so that the power system can withstand higher lightning currents and protect the safe and stable operation of the power system. Therefore, it is necessary to use a variety of advanced scientific methods to prolong the service life of the arrester to the greatest extent, and slow down the aging speed of the resistance. It is also necessary to improve the installation and use environment of the arrester. Any link of various factors cannot be ignored.