The new type of fast vacuum circuit breaker developed by the State Grid Ningxia Electric Power Research Institute has recently successfully passed the test in Xi'an High Voltage Electrical Research Institute. This circuit breaker is the world's first ultra-high pressure fast vacuum circuit breaker, which greatly improves technical indicators and operating efficiency.
When the grid is running, circuit breakers act like dam gates on rivers, and when flooding occurs downstream, they must be quickly closed. Similarly, when a short-circuit fault occurs in the power grid, the short-circuit current generated by the fault must be quickly cut off with a circuit breaker. If it cannot be cut off effectively in time, it will burn the power grid equipment at best, and cause a large-scale power outage at worst. Using the traditional circuit breaker, the short-circuit current breaking time is more than 60 milliseconds, while the fast vacuum circuit breaker, the short-circuit current breaking time is only 20 milliseconds, which can greatly improve the stability level and power quality of the power grid.
The scientific research team led by Ai Shaogui, chief technical expert of State Grid Ningxia Electric Power Co., Ltd., after 5 years, carried out thousands of tests and overcome a number of technical difficulties, and in 2013 developed a 10 kV/80 kA large-capacity fast vacuum circuit breaker using electromagnetic repulsion structure, and with the circuit breaker as the core component, with the current limiting reactor, high-voltage platform, platform energy supply device and measurement and control system, successfully developed the world's first response time within 20 milliseconds, short-circuit current limit rate of 40% 330 kV zero-loss fast switching type current limiting device. In 2015, it won the first prize of scientific and technological progress of the State Grid Corporation, and in 2016, it was authorized by the United States invention patent, so far many technical indicators of the current limiting device are still at the international leading level.
The advent of ultra-high voltage fast vacuum circuit breaker can greatly enhance the ability of safe and stable operation of power grid, and has good social and economic benefits and promotion and application prospects. A zero-loss fast switching current limiting device can save millions of yuan in electricity bills a year, and it is estimated that the promotion of Ningxia Power Grid can save about hundreds of millions of yuan in electricity costs every year.
How to accelerate the adaptation to the development and construction of China's UHV power grid and new energy to ensure the safe, reliable and stable operation of the power grid? How to further improve the opening time of the traditional circuit breaker and solve the excessive inrush current? In the face of the common attention of the world's power science and technology circles, there is good news from Xi'an High Voltage Electrical Research Institute recently: 363kV/5000A/63KA fast vacuum circuit breaker has made a key technological breakthrough, increasing the breaking short-circuit current time from 60 milliseconds to 10-20 milliseconds.
What does 60 ms vs 20 ms feel like? According to the definition of the medical community, it takes about 0.1 seconds, or 100 milliseconds, for a normal person to blink his eyes, 60 milliseconds means that it is too late to complete a blink, and 20 milliseconds is only equivalent to one eyelid flirtation. In the moment of electric flint, the fast vacuum circuit breaker successfully completed the opening action, successfully cut off the fault line of the power grid, and ensured the stable and safe power supply of power grid equipment and thousands of households.
Further reading:
The world's first ultra-high pressure fast vacuum circuit breaker was successfully developed with a breakthrough from 60 milliseconds to 20 milliseconds
Original title: Saving hundreds of millions of yuan every year| This "artifact" to protect the power grid came out in Ningxia
