What is a good temperature measurement method for circuit breakers

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

The function of medium voltage vacuum circuit breakers

Medium voltage vacuum circuit breakers are mainly used in three-phase AC 50Hz, 6-10kV power systems, playing the role of breaking circuits. They can be used for protection and control of power plants, substations, industrial and mining enterprises, and other electrical equipment. The existing vacuum circuit breakers consist of vacuum bubbles, operating mechanisms, contacts, and contact arms. The basic principle is to achieve the purpose of breaking the circuit after extinguishing the arc with a vacuum bubble. The passage of current generates heat, and the resistance in the contact arm and vacuum bubble is very small. According to Joule’s law, the heat generated is very small and can be ignored. However, the contact of the circuit breaker will have a much higher resistance with changes in installation technology and contact area. The increase in resistance increases the risk of contact heating.

The reasons for the temperature rise of medium voltage switchgear

Nowadays, the challenges faced by medium voltage distribution network systems are increasing day by day. Abnormal temperature rise of switchgear often brings unpredictable consequences. Therefore, monitoring and diagnosing the temperature rise of switchgear is very urgent and necessary. As the core component of switchgear, circuit breakers are the key and only movable component that connects the entire power generation system and transmission and distribution system. Therefore, the normal operation of switchgear circuit breakers directly affects the stable operation of the power system. The main reason for high or abnormal temperature rise in the main circuit during circuit breaker faults and accidents is due to poor contact between the dynamic and static contacts, increased contact resistance, and abnormal circuit temperature. If not detected and dealt with in a timely manner, it will further exacerbate heating and oxidation, resulting in phenomena such as melting and falling off of contact fingers, burning of contact heads, deterioration of insulation materials, and even fire, leading to safety accidents such as switch explosions.

Temperature measurement of medium voltage switchgear circuit breakers

Medium voltage switchgear is a common power supply equipment, in which the circuit breaker is a switch device used to close, carry, and open the power supply circuit. It is an important control device. Once the circuit breaker fails, it is easy to cause power grid accidents and economic losses. Circuit breakers are prone to hot spots at the plum blossom contacts. If not detected in a timely manner, it is easy to cause power accidents. Therefore, it is necessary to use fiber optic temperature measurement technology to monitor the circuit breaker.

The shortcomings of traditional vacuum circuit breaker temperature measurement methods are as follows:

1. Unable to measure the temperature of 6 contacts in real-time;

2. Unable to remotely monitor the temperature of the circuit breaker contacts;

3. Unable to provide temperature risk warning for circuit breakers.

FJINNO believes that traditional circuit breaker temperature measurement devices cannot meet the function of circuit breaker temperature detection, let alone determine the status of the circuit breaker based on this temperature.

Fiber optic monitoring system for medium voltage circuit breakers

The fluorescent fiber optic temperature measurement device used for medium voltage circuit breakers can actively monitor the temperature operation status of circuit breakers and switchgear without affecting the operation of the circuit breaker. It has excellent temperature measurement performance, can improve the reliability of power equipment product operation, and is easy to operate, ensuring the personal safety of operation and maintenance personnel. The fluorescent fiber optic temperature measurement device has a simple structure, reasonable price, and reliable insulation, especially suitable for various specifications and models of circuit breakers. The temperature measuring circuit breaker can measure the contact temperature in real time under normal operation of the circuit breaker, display the contact temperature of the circuit breaker on the LCD display panel, and remotely monitor the circuit breaker temperature through computer connection, setting alarm points for the operating temperature of the circuit breaker.
FJINNO has independently developed a device that can measure the temperature of live monitoring circuit breaker contacts. The use of fluorescent fiber optic measurement can effectively solve the problem of high voltage creep and withstand voltage. The 6-channel contact temperature measurement simultaneously meets the requirements of real-time monitoring of circuit breaker temperature.