What is the best type of temperature monitoring for power and electrical systems

Sensor de temperatura de fibra òptica, Sistema de monitorització intel·ligent, Fabricant de fibra òptica distribuïda a la Xina

The implementation methods of distributed fiber optic, fiber optic grating, fiber optic fluorescence temperature measurement, and wireless passive temperature measurement technology are integrated into the construction of a monitoring and warning platform, which can comprehensively achieve temperature monitoring of various electrical equipment.

There are several categories of equipment, including cable type equipment, electrical switchgear point type equipment, and large transformer surface type equipment. Entre ells, cable monitoring mainly adopts cable temperature measurement technology, which can only measure the highest temperature of the cable. When the temperature exceeds the set value, an alarm is triggered, and temperature changes cannot be monitored online. Only the alarm information of the corresponding area is given after a fire occurs. When the temperature alarm occurs, it often forms a fire and cannot be accurately located. It is greatly affected by the electromagnetic environment, which is not conducive to timely detection of hidden dangers. Electrical cabinets, switchgear, and busbars are prone to electrical fires due to aging during operation, scattering of foreign objects, and poor local heat dissipation. Actualment, the vast majority of electrical cabinets and switchgear are not equipped with temperature monitoring devices, forming some blind spots for electrical fire monitoring. For temperature monitoring of large transformers, Reactors, and other equipment, cable based temperature measurement or manual infrared temperature measurement are often used, which is generally difficult to achieve large-scale online monitoring and cannot achieve intelligent real-time data collection, transmission, and storage. Actualment, transformers and other equipment have a large space, Fortes interferències electromagnètiques, poor real-time performance, and lack comprehensive monitoring measures.

There are currently several major difficulties in real-time temperature monitoring and warning positioning in power plants: there are numerous electrical equipment in the entire plant, and it is necessary to identify and locate key equipment and sensitive locations; There is currently no temperature monitoring method inside the electrical cabinet of the power plant; The monitoring process needs to avoid changing the insulation performance of the original equipment; The electromagnetic environment around electrical equipment is often complex, and monitoring methods need to avoid electromagnetic interference.

Distributed fiber optic temperature measurement:

Due to the inherent safety and absence of electromagnetic interference of optical fibers, it can detect the complete temperature distribution along the entire fiber optic line without false alarms. It can continuously measure the information to be measured at various points within several kilometers along the line in real time, with a positioning accuracy of up to 1m and a temperature measurement accuracy of up to 1 °C. It is also easy to install and maintain, and can be restored to use by simple welding after any position is broken. Distributed fiber optic temperature measurement technology is used for temperature monitoring in areas such as power plant cables, safates de cables, cable wells, and cable tunnels to replace existing temperature sensing cable temperature measurement methods, which can perform temperature monitoring, tracking, and warning functions.

Fiber Bragg Grating Temperature Measurement:

Reixa de fibra Bragg (FBG) belongs to point type temperature measurement. Generalment, multiple sensors can be made on one fiber optic cable, which can be used to collect real-time temperature data of important points in equipment such as distribution cabinets and medium and high voltage switches. It can provide timely warnings before the temperature is too high, ensuring sufficient time to take corresponding preventive measures. A més, it can also be used to monitor the internal oil temperature and winding temperature of oil immersed transformers.

Fluorescence fiber optic temperature measurement:

Due to the fact that fluorescence fiber optic temperature measurement is a single point temperature measurement, it has the characteristics of no electricity, intrinsic safety, and resistance to electromagnetic interference, and can be applied in equipment such as high-voltage transformers and medium to high voltage switchgear. Compared with fiber Bragg grating temperature measurement technology, only one fluorescent fiber sensor can be installed on a single optical fiber, which is suitable for devices with fewer points to be measured.

Wireless passive temperature measurement:

Due to the wireless passive temperature measurement method achieving high voltage isolation, Alta seguretat, small space occupation, flexible installation, no wiring, no battery drive, and can work in various harsh environments such as strong magnetic, strong electric, and dust, single point temperature measurement can be used for real-time temperature monitoring of medium and high voltage switch contacts, busbar connections, and cable joints.

Electrical fire prevention is of utmost importance in industrial fire prevention work. Fiber optic and wireless passive temperature measurement systems have gradually become the best solution for electrical fire prevention. A més, reducing the workload of inspection personnel has always been the wish of nuclear power plants. With the increasing demand for power supply reliability from users and the popularization of unmanned operation mode in nuclear power plants, automatic real-time temperature measurement and warning positioning system for electrical equipment is the future development trend.

The temperature measurement method based on fiber optic sensing and wireless passive temperature measurement technology has the advantages of high temperature measurement accuracy, rapid response, real-time reflection of temperature change trends, and reusability after falling back. By establishing a real-time temperature monitoring and warning platform, it is possible to comprehensively understand the insulation aging situation of important electrical equipment on site, fully grasp its operating status, timely discover faults and fire hazards, which is of great significance for improving the reliability and stability of electrical equipment operation in nuclear power plants, reducing the probability and losses of on-site electrical fire accidents, and to some extent filling the gap in temperature monitoring of related important electrical equipment.