NEWS
Supported by the major scientific research project of South China Power Grid, the research and development of high-capacity short-circuit current interrupting device and its engineering application, Huazhong University of Science and Technology has successfully passed the 100kA class short-circuit current interrupting test for 220 kV system, which makes the breaking capacity index of high-voltage circuit breakers for 220 kV system in China reach the highest international level.
Every high temperature season, the electricity load increases sharply, and some areas begin to limit electricity, which brings inconvenience to people's life and production. You must be familiar with such scenes. However, as early as 2007, Pan Yuan's team of academicians from Huazhong University of Science and Technology tackled the technical problems, with the goal of making electricity free from constraints.
With the initiative of scientific research, the team embarked on this "unknown" journey, which lasted 11 years. They broke the situation that our country followed foreign countries in the field of high-voltage switchgear technology in the past and explored a set of completely independent and innovative Chinese solutions.
"Don't wait for problems to arise to solve them."
On September 17, 2018, Academician Panyuan, Professor He Junjia and Yuan Zhao designed and developed a high-capacity short-circuit current interrupting device for 220 kV system, which successfully passed the 100kA class short-circuit current interrupting test in Xi'an National High-voltage Electrical Appliance Product Quality Supervision and Inspection Center. This indicates that the interrupting capacity index of 220 kV high-voltage circuit breakers in China has reached the highest international level.
"The idea put forward by Academician Pan is actually very advanced." Yuan Zhao, who participated in the whole process of R&D, has been deeply impressed by Pan Yuan's vision. At that time, he said, it was normal for "grid" enterprises to adopt power restriction measures to solve the problem of soaring power load, because the difficulty of research and development to solve the problem was relatively large, and it was a future-type local problem.
Yuan Zhao vividly drew an analogy: "It's like the single and double traffic limit adopted by the city now. Although it can partly solve the traffic problem, it sacrifices the convenience of travel and has not fundamentally reversed the situation."
Pan Yuan's idea was "fantastic" at that time. Instead of improving the interrupting ability of a single circuit breaker like other people, it realized parallel connection of circuit breakers through high coupling reactor, and doubled the interrupting ability of circuit breakers. Yuan Zhao mentioned that one of the key design points is the high coupling air core split reactor, through which the switching arc can be connected in parallel. Before that, the parallel connection of switching arcs was considered impossible.
It is not easy to put design into practice. He Junjia, a core member of the team, remembers that when the technical proposal was first put forward, the outside world was constantly questioning. "This is clearly two things that can't be put together!" "You can't even do it! We don't have such a large short-circuit current in the power grid now, let's talk about it later."
In fact, such research is not alarming. At that time, some foreign companies have invested a lot of money in the research and development of large capacity circuit breakers. The 252 kV circuit breaker developed by them can break 90 kA short circuit current. He Junjia revealed that a set of large-capacity interrupting devices monopolized by foreign technology costs about 120 million yuan, which is very expensive. Of course, the core technology involved is also the patents of the other company, which will never be disclosed easily.
"Do it, do it! Do it! It is the responsibility of a scientific researcher to meet the needs of the country. Although we have not realized the importance of large capacity interruption, it is not too late to solve the problem when it really arises. We can't be confined now!" At that time, Pan Yuan's absolute words echoed in He Junjia's ears.
"This is the right way."
"When we went to Xi'an to do the experiment, we wore short sleeves, and when we came back from the experiment, we had to wear the thickest down jacket." From theory to experiment, no one has more experience than Yuan Zhao: "Do experiments in the daytime, find problems in the evening, cycle like this every day, and hardly have time to go to the hotel to rest. The test station is large, empty and cold, which can freeze us to death.
In the 11-year-long "exploration" of scientific research, many problems have been encountered for the first time in the world. When falling into the "pit", we can only "climb out" a little bit. There is no sharing of scientific experience, no data to be found, and even the same scientific research ideas can not be used for reference. This is doomed to be a hard bone to chew.
The seemingly insignificant details of the size of the casting die, the tightness of the wire winding and even the welding angle of the incoming and outgoing wires play an important role in the experiment. "You have to go to the workshop and stare at the workers, but you really have to do it yourself." Yuan Zhaobi said that he could not remember how many times he had gone to the workshop.
If it's not right, come back again. If it's not right, go ahead and do it again. With the spirit of excellence craftsmen, teams and workers work hard together, stubbornly turning the drawings in the laboratory into physical objects.
"Sometimes it's doubtful whether a design that feels okay will succeed if it's calculated or verified over and over again." When depressed, there was a man who seemed to Yuan Zhao like a night lighthouse, that is Panyuan.
Talking about the old scientist who insisted on scientific research in his early years, Yuan Zhao admired him with admiration: "At such an old age, he still thought of what he would come to the laboratory to discuss even in the evening. When I think of him, there's no reason why I can't do it well."
Entanglement or even suspicion, but ultimately choose to persist. Because this is the demand of the country and the responsibility of scientific researchers. From 2007 to 2018, the whole team ran all the way, completing the road of "from scratch" and "thorns" all over the country.
