With the further development of the social economy, the demand for power supply reliability is getting higher and higher. With the advancement of power production technology, the operating voltage of the power grid is constantly increasing; with the increase of the power grid, the capacity of the unit is increased, and the transmission distance is longer; and the sealing and combination of the equipment are also constantly being strengthened. Equipment accidents accounted for the highest proportion of all accidents, some as high as 92%. The production equipment, boilers, generators, power transmission and transformation parts of the power industry are operating under the conditions of high temperature, high pressure, high speed rotation, high voltage, and large current, which are extremely closely related to heat.
In many power outage accidents, power outages caused by local overheating of equipment occurred from time to time. In 1987, a power plant was burned due to an overheating of a lead joint of an isolation knife gate, and the wire breakage was affected by the unbalanced force. The twitching on both sides continuously caused a short circuit between phases, resulting in a large-scale blackout. Such a small overheating joint has caused great economic losses, which shows the danger of overheating. Therefore, the monitoring and management of the temperature of electrical equipment is a work that has been carried out at home and abroad, and the old method of monitoring temperature is nothing more than "contact". No matter whether a mercury thermometer, thermocouple or wax piece is used, it must be connected with the device under test. Measurements can only be made with good contact. Of course, devices that are powered, rotating at high speed, and located at high altitudes, except for the embedded temperature measurement elements, must be powered off, shut down, or climb up the equipment to measure, which is economical 1. Safe power generation brings great difficulties. As we all know, the number of equipment connectors in the power system is staggering. In order to ensure its quality, two methods are usually used in the past, namely the "direct resistance measurement method" and the "temperature labeling method". The direct resistance measurement method uses a bridge or digital micro-ohm The meter measures the resistance of the connector, which requires a large amount of work and is time-consuming and labor-intensive.
Many power supply departments in our country also use wax to attach the temperature measurement. Although these temperature measurement pieces are relatively simple, they all need to be placed after a power outage, which is time-consuming and uneconomical, and the temperature measurement range is narrow, the results are inaccurate, and the operation is inconvenient and unsafe. As the voltage level increases, the insulation distance of the equipment increases, and on devices with higher voltages and longer distances, the temperature tag method cannot be used to measure temperature at all.