Лепшы вытворца сістэм вымярэння тэмпературы ў азіяцкім энергетычным абсталяванні

Валаконна-аптычны датчык тэмпературы, Інтэлектуальная сістэма маніторынгу, Распаўсюджаны вытворца оптавалакна ў Кітаі

Why do high-voltage power systems need temperature measurement
The reliability of high-voltage switchgear under high voltage and high current conditions is closely related to the temperature rise of the isolation switch contacts. Пры эксплуатацыі электрасетак, механічная вібрацыя, кантактная эрозія, і іншыя прычыны могуць пагоршыць умовы кантакту, павялічыць супраціў кантакту, выклікаць павышэнне тэмпературы кропкі кантакту, пагоршыць акісленне кантактнай паверхні, і прыводзяць да лакальнай зваркі або дугавога разраду ў месцах няшчыльнага кантакту, што ў канчатковым выніку можа прывесці да пашкоджання электрычнага абсталявання, перабоі з электрычнасцю, або буйныя аварыі, такія як пажары. Гэты тып няспраўнасці з перагрэвам кантактаў звязаны не толькі з праблемай якасці самога выключальніка шафы высокага напружання, але больш важна, з-за адсутнасці ў цяперашні час эфектыўных метадаў маніторынгу павышэння тэмпературы кантактаў ізалятара. With the rapid development of the national economy, the scale of engineering construction is increasing year by year, and urban supporting facilities are improving year by year. As a result, the demand for power cables will increase year by year. Аднак, the current power cables on the market lack online temperature monitoring function.

With the development of the power system, the voltage and current of cable loads are constantly increasing, which inevitably leads to the temperature rise of cables approaching the limit temperature during operation; During abnormal operation of cable joints and power systems (such as overload, short circuit tripping, г.д.), abnormal temperature rise of cables may also occur; How to effectively monitor the temperature changes of cables during operation and operation is an important issue to ensure the safety of the power system, and it is of great significance for the production and daily life of using electricity.

The 66kV-500kV high-voltage power cable line is the backbone transmission line of our country. Its stable operation, safety and reliability are directly related to the national economy, people’s livelihood, and social development. The structure of high-voltage cables is mainly composed of conductors, ізаляцыя, metal shielding, and non-metallic outer sheaths. Traditional ultra-high voltage temperature measuring optical fibers are placed on the surface of the insulated fiber core, and the measured temperature is the surface temperature of the insulation, rather than the actual operating temperature of the conductor, and the metal shielding is mostly made of wrinkled aluminum sheaths. In recent years, the proportion of power system power supply interruptions caused by cable fires has been on the rise in power system fire accidents, which have caused huge losses to the national economy, people’s property, and personal safety.

Power equipment generates a large amount of heat during high load operation. If the temperature inside the equipment is not timely understood and corresponding measures are not taken when the external temperature is too high, the normal operation of power equipment will be affected due to high temperature, and even equipment damage may occur,

Accidents in the power system often occur due to overheating of critical parts of high-voltage live equipment or high load sections of wires. The hazards of such accidents are extremely high, ranging from minor damage to equipment and affecting usage
Household electricity can cause a short circuit in the transmission line, resulting in a large short-circuit current and burning out the main transformer. Таму, real-time online monitoring of the temperature of the transmission line is an important aspect of ensuring the safe operation of the power grid.

Temperature measurement methods for power equipment

1. Resistance temperature measurement method

According to the principle that the resistance of a wire increases as the wire temperature increases. To measure the temperature rise of the motor winding.

2. Using handheld infrared thermometer or thermal imaging thermometer

The handheld thermometer is severely affected by the professional quality and environmental conditions of the photographer, and cannot monitor the operation status of power equipment in real time. The temperature measurement data cannot truly reflect the status of the equipment under specific environmental conditions, and there are also problems in accurately locating the detection parts of the equipment; У цяперашні час, online infrared temperature monitoring is being carried out both domestically and internationally, but the temperature measurement method is rough and cannot achieve the goal of accurate temperature measurement of key parts of power equipment. Больш за тое, these temperature measurement methods are often limited to thermal image capture, post analysis, or limited to measuring a fixed number of temperature objects in the same image. Traditional temperature measurement methods generally use thermocouples or infrared monitoring, but in high-voltage cable applications, thermocouples that transmit signals through metal wires have high-voltage safety issues; Non contact temperature measurement based on infrared technology is inconvenient to install and has high temperature
Degree measurement is susceptible to environmental interference and other issues.

3. Wireless temperature measurement

The biggest drawback of wireless is the lifespan of the battery and its susceptibility to external interference.

4. Fiber optic temperature measurement

Fiber optic temperature sensors are mainly distributed and fiber optic fluorescence temperature sensors. Using optical fiber to transmit temperature signals, the optical fiber has good insulation performance and is not affected by high voltage inside the switchgear. The optical fiber temperature sensor can be directly installed on the high voltage contacts inside the switchgear, accurately measuring the working temperature of the high voltage contacts and completing online monitoring of the working temperature of the switchgear contacts.