The role of thermal infrared temperature sensors in monitoring switchgear

Fiber optic temperature sensor, Intelligent monitoring system, Distributed fiber optic manufacturer in China

Infrared temperature sensor monitoring technology for switchgear

With the rapid development of the economy, the demand for electricity among residents is gradually increasing. With the increase in the number of distribution network construction, the hidden dangers in the power system are gradually increasing. In the power system, switchgear is an extremely important part. The safe operation of the power system is closely related to the final power supply quality and stability. Infrared temperature measurement technology can monitor the operation status of switchgear circuits and equipment without power outage or contact with circuits, and is an important basis for judging the operation status of switchgear systems.

The infrared temperature monitoring technology for switchgear is based on the thermal radiation of power facilities, which is converted into images to determine and inspect equipment temperature. Compared with other monitoring forms, this technology has the following 5 advantages.

(1) The related devices of this technology are mostly handheld and do not have a large volume. They can be moved freely without the assistance of other devices and can be monitored comprehensively.
(2) In environments where there is no contact with the line and the voltage is different, the inspection efficiency of the substation can be improved, making the inspection have strong safety and work efficiency.
(3) This technology has a certain radiation effect, can independently carry out monitoring work, and makes the monitoring process have high accuracy and timeliness.
(4) Using computer technology to combine data and images, promoting data sharing among substations, and effectively analyzing relevant results.
(5) It can scientifically evaluate the status of various equipment in the substation, provide accurate data reference, and avoid subjective evaluation.

With the continuous development of technology, the number of oil injection equipment in substations is decreasing day by day, and leakage problems are also gradually decreasing. However, equipment still generally has abnormal problems. According to relevant statistics, the problem of heating equipment accounts for 55% of the equipment failures in switchgear. It is impossible to check the operation status of the equipment through tactile and auditory inspection. If tactile monitoring is used, it can lead to safety accidents. Therefore, relevant departments should develop the most effective monitoring plan based on the actual situation and monitor the operation status of the equipment. The use of infrared temperature measurement technology can greatly improve the quality and efficiency of technical personnel’s inspections, promote timely detection of hidden dangers in equipment, and thus maintain the stability of substation operation.

Infrared temperature measurement method for switchgear infrared temperature measurement technology

In the process of using infrared temperature measurement technology, the current temperature should be monitored first, the monitoring values should be analyzed, and the operation and heating status of the substation should be judged. But for some related accessories, this technology is difficult to implement and apply. To reduce interference in monitoring, it is necessary to ensure that there is sufficient current in the power system, and infrared temperature measurement technology is usually used during late peak hours. In addition, it is necessary to compare the results and use horizontal comparison to monitor the power outage temperature difference, and analyze the data to determine the defects of the equipment. By using this method, it is possible to effectively avoid peak electricity consumption periods. It should be noted that during monitoring, it is necessary to fully grasp the accessories of each equipment. This technology can design different infrared spectra at different times, and relevant personnel can analyze the data of relevant components to timely identify problems. It should be noted that using this monitoring technology, an effective map should be created for later comparison.

Insulator temperature monitoring

Due to the existence of various types of equipment in substations, each type is different, resulting in significant differences in the structure and heating of the equipment, which indirectly affects the authenticity of monitoring data. The reasons for producing heat in current heating equipment include ineffective contact between joints and contacts and insufficient wire area. The specific methods for monitoring such devices are as follows.
(1) Due to the exposed state of the current heating position, a thermal imager can generally be used to monitor the temperature of the equipment;

(2) There is no significant deviation between the detection data and the actual data, so the relevant temperature can be analyzed based on the detection results of the equipment. Using standard values to regulate the limitations of equipment temperature increase. The temperature difference method can be effectively used to determine the degree of equipment problems. Once the values of each current device exceed the standard value, the substation needs to arrange relevant personnel for timely maintenance.

Selecting a 200kV equipment as an inspection case, during the operation and maintenance process, technicians discovered the subtle discharge sound emitted by the switch and insulator B of the busbar. Through monitoring the relevant equipment, the final result showed that the temperature of insulator B was 2.0K higher than that of position C. Under normal circumstances, if there is no current passing through, the equipment will produce significant deviations, and relevant personnel should pay attention to the temperature difference caused by insulators. If abnormal conditions occur, operation and maintenance personnel need to implement infrared temperature monitoring every 2 hours, list all temperature measurement data, and conduct effective analysis. After 2 days of monitoring, it was determined that the temperature was continuously increasing, reaching a maximum of around 13K. The discharge sound at point B gradually changed from the initial subtle and indirect to a more significant sound. After long-term monitoring, it has been determined that there is power generation on site. By analyzing the temperature difference and sound conditions, it is determined that there are serious quality issues with the string ceramic insulators in all equipment of the substation, and the operating busbar is located in the lower lead of the insulators. If the arc is damaged due to high temperature, the wire of the burnt steel foot will fall off, causing voltage loss of the busbars at both ends inside the substation. Relevant personnel need to report the fault situation in a timely manner, submit relevant applications, and replace the insulators. Analyzing the diagnostic results, under the background of long-term operation of insulators with low resistance values, the operating voltage bears a lower voltage during the working process, while other types of voltage will bear a higher voltage, resulting in abnormal voltage differences in some insulators. Once the condition persists for a long time, abnormal noises will occur, along with discharge and corona issues.
The use of infrared temperature measurement technology can effectively monitor the temperature of voltage heating facilities. If the surface of the facility does not have a high temperature and does not have obvious temperature difference data, there will be many problems in the voltage heating equipment. Therefore, in the actual application process, technicians need to closely pay attention to some subtle temperature differences, combine them with the structure and operating principle of the equipment to conduct in-depth analysis, sort out the shortcomings in the equipment, and identify the reasons for the shortcomings.
During the operation of the substation, infrared temperature measurement technology has the function of auxiliary monitoring. By using infrared temperature measurement technology, problems with each device can be identified in a timely manner. Due to the increasing scale of power grid construction, it is necessary to provide accurate data references for relevant personnel through analysis and research of substation equipment, and encourage them to promptly identify equipment problems and abnormal conditions, ensuring the safe and continuous operation of various equipment in the substation.