Fiber optic temperature sensor for handcart switchgear

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

Due to the difference in temperature rise inside and outside the contact box of the high-voltage switchgear, the online temperature measurement device outside the box cannot directly reflect the highest temperature of the contact. Therefore, a conductive circuit heating model was established for a commonly used model of switchgear under normal and poor contact conditions of handcart contacts. The installation of existing switchgear overheating warning device sensors and analysis of temperature monitoring data provide reference, which helps to timely and accurately detect overheating hazards.

The switchgear is an important electrical equipment that plays a role in receiving and distributing electrical energy in the power system. Thanks to the development of high-voltage circuit breakers, metal enclosed handcart switchgear with convenient operation and small footprint has become mainstream. With the advancement of intelligence and miniaturization research, the internal structure of switchgear has become increasingly compact and the internal space has become narrower. Due to directly bearing user loads and poor heat dissipation, current carrying faults caused by overheating due to poor contact and other reasons have always been the main safety hazards faced by switchgear.

10kV handcart cabinet circuit breaker handcart isolation contact temperature measurement system for substations in the field of power electrical equipment

At present, the 10kV handcart cabinet mainly adopts a high-voltage metal enclosed handcart vacuum switchgear (referred to as handcart cabinet), which is composed of a circuit breaker handcart room, a busbar room, a cable room, and a relay instrument room. The cabinet is mainly equipped with circuit breakers, current transformers, grounding switches, and live display devices. This type of equipment has a compact structure, good sealing, interchangeable handcart, simple maintenance, safe operation, and convenient operation.
However, with the increase of power load, it was found that the isolation contact of the 10kV handcart cabinet circuit breaker handcart had severe heating. Moreover, due to the compact structure and good sealing of the handcart cabinet, the working position of the circuit breaker handcart isolation contact is between the handcart room and the busbar room. During normal inspections, the substation duty personnel cannot use infrared thermometers and thermal imaging devices to measure the infrared temperature of the handcart isolation contact. However, the test regulations stipulate that the test cycle for the 10kV main transformer cabinet and busbar cabinet is once every 3 years, and for the 10kV line cabinet is once every 6 years; Such a long maintenance cycle, without strengthened monitoring, will seriously affect the safe and stable operation of the equipment if the temperature is too high. During operation, there have been incidents where the main transformer of the 10kV handcart cabinet and the isolation contact of the busbar circuit breaker handcart overheated severely, causing the plum blossom contact to burn out, resulting in the transformer being unable to be put into operation and the entire station experiencing a power outage.

The fluorescent temperature measurement device independently developed by FJINNO for handcart switchgear is suitable for online monitoring of temperature of various types of switchgear, real-time monitoring of the temperature of switch contacts and other hot spots, in order to discover abnormal heating fault signs, prevent the occurrence of faults, and provide scientific data basis for “status maintenance” of switchgear through temperature history records, which is of great significance for the safe operation of switchgear equipment.