Online monitoring of SF6 gas density using sensor technology and digital circuits, a digital SF6 gas density online monitoring device is developed, and it is connected to the substation integrated automation system for remote online monitoring.
The online monitoring system of the SF6 gas density solves the problem that the mechanical density relay cannot adapt to the unattended substation to monitor the equipment operation status in real time. It is beneficial to keep abreast of the development of circuit breaker condition maintenance and the safe and stable operation of the power grid.
Sulfur hexafluoride (SF6) is a non-toxic, odorless, colorless and non-flammable synthetic gas with insulating properties and arc-extinguishing abilities that are unmatched by general dielectrics.
SF6 gas is widely used in high-voltage circuit breakers and substation equipment in the power industry around the world, and has almost become the only insulating and arc extinguishing medium in high-voltage, ultra-high-voltage circuit breakers and GIS.
The density of SF6 gas is the main indicator of the insulating and arc extinguishing properties of the gas. Therefore, the regulations of the state power company mandate that before and during the operation of the equipment, the density of SF6 gas must be checked regularly.
1. The small monitoring system with interval as the unit should be compact and economical.
2. On-site real-time visual display of SF6 temperature, pressure and density values of each gas chamber in the system.
3. Set the alarm threshold flexibly, and query historical alarm information on the spot.
4. The SF6 gas density online monitoring system locally controls the communication status of the long-distance transmission density relay, which is convenient for maintenance.
5. HMI embedded configuration software, it is stable and reliable in operation and having touch screen design, which makes it intuitive and easy to operate.
6. SF6 relay of the remote transmission type adopts electromechanical-body design. Traditional mechanical structure is used for indication and alarm, transmitter and electronic chip are used for signal acquisition and remote transmission.
1. Integrate the display density value and contact output of the mechanical dial-type SF6 relay with the digital signal output of the SF6 gas temperature, pressure and density sensor to realize the dual comparison relationship between the physical interface and the digital information.
2. Realize the remote communication function of traditional SF6 relay, online real-time monitoring and collection of data information parameters of SF6 gas temperature, pressure and density in SF6 electrical equipment.
3. When the gas in the equipment leaks, it has an advance alarm function, and can judge according to the set alarm value.
1. After the online monitoring is realized, the identification ability of operators will be improved, the pressure of staff will be greatly reduced, and the real data of substation equipment operation and safe production will be improved. At the same time, it can provide the basis for the condition monitoring and maintenance of high-voltage equipment to meet the needs of the development of smart grid.
2. The remote transmission type SF6 relay can not only maintain the functions of the original SF6 gas alarm and blocking contact, but also realize the digital signal output of gas density, pressure and temperature, and realize the remote transmission function, so as to monitor the operation status of high-voltage equipment.