INNO fibre optic temperature sensors ,temperature monitoring systems.
Many electrical manufacturers now require the use of dry type air core reactors. What are the functions of dry type air core reactors and what is the maximum temperature range of air core reactors. How to measure temperature with a reactor.
What is the temperature standard for dry air core reactors
If the maximum temperature and insulation level of a reactor exceed their insulation level, the reactor is highly susceptible to damage.
1. If the insulation level is A, it cannot exceed 105 degrees
2. If the insulation level is B, it cannot exceed 130 degrees
If the insulation level is F, it cannot exceed 155 degrees
4. If the insulation level is H, it cannot exceed 180 degrees
5. If the insulation level is N, it cannot exceed 200 degrees
6. If the insulation level is R level, it cannot exceed 220 degrees
7. If the insulation level is S level, it cannot exceed 240 degrees
What are the functions of dry air core reactors
In the field of power technology, ultra-high voltage and ultra-high voltage power grids have the ability to transmit large capacity and long distances, and are the backbone networks of national power transmission. Dry type hollow core reactors play an important role in compensating reactive power, limiting short-circuit current, and filtering out high-order harmonics in the power grid system, and are one of the important power equipment to ensure the stable operation of the power system. Dry type hollow core reactors have advantages such as good linearity, low noise, high short-circuit resistance, and easy maintenance. They play an important role in maintaining voltage stability in power systems, limiting short-circuit currents, and compensating reactive power.
The importance of online temperature monitoring system for dry-type hollow reactor
Due to the harsh working conditions of dry-type air-core reactors used in high-voltage power grids, which are mainly used outdoors and without maintenance, accidents of dry-type air-core reactors occur frequently. Statistics show that the main causes of accidents in this type of reactor are deterioration of the electrical insulation performance of the reactor under high temperature and severe combustion damage, especially the latter can spread to other electrical equipment, leading to accidents and endangering the safety of the power grid. Therefore, effective monitoring of the operating temperature of the reactor is the technical key to ensuring the stable operation of the dry air core reactor. High voltage reactors are one of the widely used electrical equipment in the power system, and they are also one of the weakest links in the operation of the power system. During long-term operation of high-voltage power reactors, local overheating is prone to occur, which can cause rapid local aging or surface discharge due to external environmental factors, resulting in a rapid increase in wire turn current, damage to wire turn insulation, cause inter turn short circuits, and even discharge combustion, which is a major safety hazard in power grid operation. In the initial and developmental stages of the fault, only local temperature changes occur, and the overall temperature change of the equipment is not significant. However, during the damage period of the fault, the overall temperature of the equipment rises sharply, the insulation performance deteriorates sharply, and other electrical equipment spreads, causing catastrophic accidents. The interval between the damage period of the reactor equipment fault and the actual occurrence of the disaster is usually in the range of 30s to 100s.
Dry type air core reactors are widely used in power systems. In recent years, incidents of burning dry type air core reactors have occurred frequently, causing production safety accidents and property losses. Dry type hollow reactor operates under natural heat dissipation conditions. When the system experiences overvoltage and overcurrent, high harmonic content, or environmental temperature rise, the reactor often generates severe heat. In the case of poor heat dissipation conditions, the temperature of the reactor packaging increases. Prolonged operation at high temperatures can damage the insulation of the packaging, ultimately leading to inter turn short circuits and causing the reactor to burn out. Therefore, monitoring the packaging temperature of dry-type hollow reactors is crucial.
Fiber optic temperature measurement system for dry-type hollow reactor
In the era of rapid development of electricity, dry-type air-core reactors were frequently burned out in substations, leading to poor power quality in transmission and distribution circuits, and affecting the stable operation of the power grid.
The method commonly used for temperature detection of dry-type hollow reactors is infrared temperature measurement. Infrared temperature measurement method is to measure the temperature value of an object through its infrared radiation intensity, which can achieve non-contact measurement. However, this method can only be used to measure the surface temperature of objects and cannot accurately measure the internal temperature of objects. Moreover, when the measurement environment temperature is too high/too low, or there is a large amount of dust in the air, the sensitivity and accuracy of infrared temperature measurement will deteriorate. The principle of reactor temperature monitoring is mainly to provide fault warnings during the damage period of reactor equipment, leaving limited time and means for on-site technical personnel to take rescue and maintenance measures. This seriously limits the application and role of temperature monitoring technology in the power grid and power system. Therefore, it is necessary to provide a technical solution that can effectively identify and warn of the initial and developmental stages of reactor equipment faults when monitoring the safe operation status of reactor equipment.
In the converter station, a large amount of magnetic leakage occurs during long-term operation of dry-type hollow reactors, which can cause eddy current losses at components such as post insulators, support plates, and other components that connect or install reactors, resulting in significant temperature rise. This poses a great safety hazard to long-term operating reactors.
FJINNO’s fluorescence fiber optic temperature measurement device is independently developed and produced using the working principle of fluorescence fiber optic sensors. The product is easy to operate, and fiber optic sensors have unique advantages in electromagnetic immunity. Applying them to measure the temperature and strain of dry-type hollow reactors, online monitoring of reactor temperature operation, and timely detection of safety hazards, avoiding accidents and preventing their expansion have a very positive effect. The fiber optic temperature measurement system can detect the temperature on the surface of the internal components of the dry type hollow reactor online, reflect the operating conditions of the dry type hollow reactor, and then switch it reasonably to solve the problem of frequent burning.