At the end of 1994, the Basic Bureau of Chinese Academy of Sciences invited six academicians and eight experts to hold a symposium on HT-7U superconducting tokamak project in Hefei, and formally put forward the HT-7U project for the first time.
1at the beginning of 996, some academicians of the two academies made a preliminary evaluation of the "Ninth Five-Year Plan" national major scientific projects in Beijing Jingxi Hotel. The construction of HT-7U device passed the acceptance of national experts for the first time and was listed in the top ten projects.
1June, 1997, the national leading group for science and technology approved the application for the establishment of HT-7U large scientific engineering project of China Academy of Sciences, and the project officially entered the operation procedure for the establishment of major national scientific engineering projects.
1997 10, the state planning commission entrusted China academy of sciences to preside over the "expert review meeting of HT-7U project proposal"; The construction scheme and plan of the project have been well received by the participating experts.
In April, 1998,10-1and HT-7U formally passed the evaluation and demonstration of the expert review meeting of HT-7U project proposal hosted by China international engineering consulting company entrusted by the state planning commission.
1 On July 8, 1998, the State Planning Commission officially approved the HT-7U project proposal (JY [1998]1303), and agreed to the construction of the national major scientific engineering project "HT-7U superconducting tokamak nuclear fusion experimental device" sponsored by China Academy of Sciences, with the investment of1.
1998 10, the feasibility study report of HT-7U passed the expert review meeting hosted by the Infrastructure Bureau of Chinese Academy of Sciences.
199865438+February, the feasibility report of HT-7U was approved.
1999 10, the preliminary design and budgetary estimate of HT-7U expansion were adopted.
In June 2000, 5438+ 10, the State Planning Commission officially approved the construction of HT-7U(JY[2000] 1656).
On June 4th, 2000,165438+1October 4th, No.2 refrigerator from Russia was successfully debugged, and the first round of superconducting coil experiment was carried out. In the early morning of 4th 1, the refrigerator dropped to the helium liquefaction temperature, producing liquid helium.
On 2001May 3 1 day, the contract for external processing of the external vacuum and vacuum chamber of HT-7U mainframe was signed (right), marking the official entry of HT-7U mainframe into the manufacturing stage.
On August 20th, 200 1 year, the HT-7U current lead was installed in the experimental Doinet (left).
On August 22nd, 20001year, —XK2425/IB CNC gantry milling (provided by Wuhan Machine Tool Factory), an important processing equipment for HT-7U longitudinal coils, passed the acceptance test successfully (right). The outermost surface of the longitudinal field superconducting magnet is a large D-shaped cross-section coil box with high dimensional accuracy, large volume, ultra-thin, deep groove and full welding. The welding blank of the coil box processed by the outsourcing unit is put into the longitudinal coil processed by VPI at one time and then sealed and welded, which is completed on the NC machine tool.
On August 26th, 200 1 year, HT-7U 600m CICC virtual conductor was successfully trial-produced.
200 1 10 year1October 29th HT-7U large superconducting model coil (left) was successfully tested. The superconducting experimental system began to cool down at 7: 00 pm on the 22nd, and entered the superconducting state at 2: 20 pm on the 27th, with the mode of 14:00.
When the I-type model coil reaches 5.5k and 14:20 close to the working temperature, the current adding experiments of various modes are started. On 28th, the continuous experiments of high current and high current change rate were successful, and the working conditions of each system were basically normal.
2001165438+1On October 27-28, VPI- 1000 epoxy resin vacuum pressure impregnation equipment (pictured right) passed the technical indexes stipulated in the contract and passed the equipment acceptance smoothly. On February 6th, 2002, the longitudinal winding of HT-7U first cake 1: 1 was completed (left).
On March 1 1 day, 2002, the first 604m CICC catheter for superconducting longitudinal field coil in HT-7U was successfully born. On the 20th, the conductor was formed by square pressing (right). HT-7U needs to produce 58 wires with a length of 32km, and * * * has more than 2,900 connectors. In order to ensure the quality of the joints, six inspection methods (X-ray, ultrasonic, coloring, endoscopic plug gauge, vacuum leak detection and pressing) were used to inspect the joints one by one. In order to solve the problem that the cable passes through a 600-meter-long pipeline with a clearance of 1 mm, a small-diameter ribbon-drawing clamp was specially designed and obtained the national patent right. Through continuous exploration and practice, the pre-pressing molding process of CICC conductor finally reached the size control accuracy of 0.65438 0 mm.
On April 3, 2002, HT-7U superconducting center solenoid model coil was successfully demoulded, which marked the successful end of center solenoid model coil VPI.
On April 9, 2002, the second 600-meter CICC conductor of HT-7U was successfully pressed and formed after threading the cable.
On July 13, 2002, the gantry CICC wire pre-bending forming machine has started winding the TF002A coil (left), which can be wound simultaneously with the cantilever forming machine, and the winding progress can be doubled.
On August 2, 20021day, the first production line of winding workshop, the cantilever CICC wire pre-bending forming machine TF00 1B, went off the production line. On August 27th, the second production line, the TF002A coil on the CICC wire pre-bending machine with gantry structure, rolled off the production line (right).
On February 9, 2002, 65438, HT-7U superconducting coil VPI equipment -4200 epoxy resin vacuum pressure impregnation equipment passed the acceptance (left). This set of equipment specially developed for HT-7U is the first set of VPI equipment integrating vacuum, pressure and pouring functions in China, the largest vacuum pressure pouring equipment in China at present, and the VPI equipment with the highest technical requirements and the highest technical content among similar equipment. It has high vacuum degree, advanced film degassing, safety, easy control, uniform temperature heat transfer oil heating system, reliable performance, high degree of automation, hydraulic, staggered and fluororubber sealing structure. The equipment has undergone strict inspection before leaving the factory in Shenyang, and obtained the certificate of pressure vessel.
On March 6th, 2003, the VPI of HT-7U vertical dumb cable coil was cured (right). On May 2, 2003, the first longitudinal field coil VPI of HT-7U was successfully manufactured. The longitudinal field coil after VPI treatment has regular appearance and transparent color. Its integrity, insulation strength and dimensional error fully meet the design requirements.
On May 12, 2003, HT-7U made great progress-the first prototype coil of superconducting center solenoid (computer design drawing on the left) passed the performance test successfully. The central solenoid coil is the most critical component of HT-7U, and its function is to generate plasma current in the initial stage through rapid magnetic flux change. During the "May 1" period, a solenoid coil connected with the superconducting center was installed in the experimental device. On the 6th, the experimental system began to cool down. The performance test starts after reaching the superconducting working temperature range at 1 1. Because the performance test must be completed under the condition of rapidly changing high current, high requirements are put forward for quench protection technology, power supply and its control technology, low temperature, vacuum and measurement. On June 5438+02, all the expected performance tests were completed and a series of encouraging and important results were obtained. Experiments show that the polar field power supply system completely meets the design requirements, which lays a solid foundation for the successful operation of HT-7U device in the future. The success of this experiment shows that the most difficult and challenging superconducting central solenoid coil of HT-7U has completely met the design requirements.
From June 30th to July 7th, 2003, HT-7U successfully tested the superconducting electromagnetic properties, mechanical properties and thermal-hydraulic properties of the longitudinal field prototype coil (right). After 100 hours of cooling, the coil successfully entered the superconducting state. Then, simulating the working conditions of the longitudinal field of the HT-7U device, superconducting experiments of the prototype coil of the longitudinal field were carried out at 14.3 kA and 16 kA respectively, and the quench current of the coil at 6.8K K was tested. The results show that the performance of the coil meets the design parameters and fully meets the requirements of the future HT-7U operation. The longitudinal field coils of HT-7U are D-shaped, *** 16, which are arranged along the circumferential direction to form a longitudinal field coil system, providing a stable annular magnetic field to confine the plasma.
On July 28th, 2003, HT-7U super-large third winder was put into production (left).
On August 7, 2003, the performance test of TF005 superconducting magnet of HT-7U began.
In June 2003, the project name was changed from HT-7U to EAST.
June 2003: 65438+1October11,composed of 25 famous directors of fusion research institutes, heads of international fusion research organizations and "International Thermonuclear EAST Reactor" from Britain, Germany, the United States, Japan, Russia, France and India. Experts believe that EAST will be an advanced scientific equipment that will have an important impact on the world's fusion research, and it is also the first tokamak in the world with fully superconducting magnets and flexible cooling structure, which can achieve steady-state operation. EAST is a great progress in China's fusion research, and it has achieved great success in training a new generation of fusion researchers in China. EAST has advanced plasma shape (non-circular cross section), divertor power and impurity treatment ability, and can carry out research on key physical and engineering problems under steady-state conditions, which is directly related to the construction of fusion reactor and ITER.
On June 5438+1October 65438+May, 2003, the winding of the first large-scale poloidal field coil in EAST was completed.
On March 2, 2004, the winding of the first large polarization field bias filter coil in EAST was completed.
On March 30th, 2004, the large field superconducting coil of the East Pole was successfully impregnated by vacuum pressure (left). This is a high-tech, high-difficulty, high-risk innovative work, which is the first case in China. The successful development of this project marks another breakthrough in the major technical problems of Oriental Science and Engineering.
On April 1 day, 2004, the first longitudinal superconducting magnet in EAST passed the acceptance of the expert review group (right). The large D-shaped superconducting magnet is the TF3 longitudinal field magnet of the EAST device. In the process of development, a variety of domestic innovative key technologies and unique processes have been adopted. Strict inspection shows that the magnet is of excellent quality and fully meets the design requirements. The development of this magnet fills the gap of large superconducting magnets in China and makes an important contribution to the international fusion community. The experience and lessons gained in the research have accumulated valuable experience for ITER (International Thermonuclear Experimental Reactor).
On June 12, 2004, with the successful winding of the last in-pipe armored cable superconducting conductor (CICC), all CICC conductors required by EAST were completed in the CICC production line with high quality.
On September 2, 2004, the welding blank of superconducting longitudinal field coil box, the core component of EAST and one of the most important structural components of superconducting magnet, which was developed and processed by Wuhu Shipyard, passed the acceptance test. Wuhu Shipyard completed the processing of all east billets 4 months 10 days ahead of schedule (the picture on the left shows that Wuhu Shipyard officially started the filing box on June 18, 2002). After many times of forming and welding process tests, a large number of major technical difficulties such as large-area welding of 3 16LN ultra-low carbon and high nitrogen nonmagnetic stainless steel, welding stress relief and deformation control of large-scale welded components with complex contours have been overcome, which has filled the gaps in China and reached the international advanced level, and made important contributions to the construction of EAST.
At the end of September, 2004, EAST completed the winding of all 34 longitudinal field coils, 7 central solenoid coils, 4 large polar field coils, 4 divertor coils and 2 test coils, with a total of ***5 1 large superconducting coils. The deviation of the overall dimensions of the coils is less than 1.5 mm, reaching the international advanced level.
On June 5438+1October 65438+April, 2004, the inspection team composed of EAST went to the Nuclear Chemical Company of Shanghai Boiler Factory to inspect and review the inspection data report and surface treatment status of the middle ring and head of the vacuum dewar outside EAST (right). The acceptance team thinks that the overall quality of the two components of Dewar is excellent and meets the design requirements, especially in the precision control of window position and scale, and agrees to accept it.
On March 8, 2005, EAST successfully completed the packaging of the ninth group of TF coils, and started the pre-assembly of the fourth group of vertical field coils (16 TF coils, with four groups pre-assembled).
On August 22nd, 2005, the EAST central solenoid assembly weighing 15.7 tons and the upper deflection coil weighing 8.7 tons were installed in place (left).
From June, 5438 to October, 2006, EAST completed the pre-assembly, and entered the experimental stage of vacuumizing, cooling and electrifying on February 20th.
On March 3rd, 2006, 2 1: 55 East 12 pole was successfully energized to the excitation coil (the waveform diagram of energizing experiment is shown on the right). The purpose of this experiment is to detect the thermal and hydraulic characteristics of magnets, coil boxes, transmission lines and other components, compensate and debug the poloidal field coils through quench detection, debug the electromagnetic measurement system, debug the joint resistance, and optimize the poloidal field power supply control system. The collected experimental data show that the first maximum current of 12 polar field coil is 1 kA, the energizing time is 45 seconds, and the rising and falling rate is 50 a/s. In the experiment, the polarized field magnets * * * of 12 and 14 are energized for 22 times. Eight systems, including vacuum, cryogenic, polar field power supply, longitudinal field power supply, technical diagnosis, electromagnetic measurement, water and electricity supply and general control, participated in this experiment, and all of them achieved the experimental objectives to varying degrees. Starting from the next day, the remaining polar field coils will be energized separately. After success, the whole pole is electrified to the field coil, and the longitudinal field coil is electrified.
On March 7th, 2006, EAST completed the first engineering debugging (left). The main purpose of the first engineering debugging is to test the performance of the main engine and the capacity of related subsystems, explore the feasible operation mode in the future, measure the key technical parameters of the main engine and main subsystems, verify the reliability of various safety protection systems, and provide necessary data and accumulate experience for successful operation. In debugging, the most concerned low-temperature debugging and magnet electrification test have achieved complete success. After being put in place under vacuum and low temperature, the longitudinal field magnet and 12 polar field magnet were tested for 260 times from March 2003 to March 2007. The longest power-on time reaches 5000 seconds, the maximum current reaches 8200 amps, and the corresponding central field strength of the equipment reaches 2 Tesla. The main control system, vacuum system, cryogenic system, data acquisition system, water cooling system, power supply system, device technical diagnosis system, quench protection, vacuum magnetic configuration measurement system, superconducting transmission line, high temperature superconducting current lead, copper current lead and plasma control system operate normally, ensuring the safety and success of the power-on test.
On September 26th, 2006, in the first plasma discharge experiment, EAST successfully obtained a high-temperature plasma discharge with a current of more than 200 kA and a time of nearly 3 seconds (left), marking the first time that the world's first fully superconducting non-circular cross-section tokamak nuclear fusion experimental device was built and put into operation in China. EAST began to turn to the physical experiment stage, and under the stable operation condition of the fully superconducting magnet, many experimental results were obtained, such as the maximum current of 500 kA, repeated discharge for 9 seconds, divertor plasma with large elongation ratio and so on. Relevant design concepts and technological innovations, including the design and manufacture of large superconducting magnets, large-scale ultra-low temperature refrigeration technology, and arbitrarily controllable and rapidly changing high-current equipment technology, are the first in China and have reached the international advanced level.
On June 65438+1October 13- 14, 2006, the second meeting of the Oriental International Advisory Committee was held in Hefei (right). Twenty-nine leaders and senior scientists from ITER project and world-class fusion research institutions in Europe, America, Russia, Japan, South Korea and India attended the meeting. The meeting heard the report of the EAST project, the progress of the project, the results of the first experiment and the future experimental plan, and visited the discharge experiment and various subsystems in the experimental hall. International consultants discussed the construction, system improvement, future experimental plan and research of EAST project for 10 hour, and the resulting conference report pointed out that EAST is the only tokamak device in the world similar to ITER's full superconducting magnetic field design. The Committee was impressed by the high-quality construction of EAST. In such a short time, the design, pre-research, construction and trial operation were independently completed, and the extraordinary achievements of world fusion engineering were achieved. This outstanding achievement is an important milestone in the development of fusion energy in the world. High-power heating, current drive and better diagnosis are necessary for further research projects in the future. Once these plans are realized, EAST will be at the forefront of the scientific research plan for developing steady-state high-performance plasma physics, thus contributing to supporting the development of ITER and fusion energy. It is suggested that sufficient resources should be given to achieve these scientific goals as soon as possible.
On June 22nd, 2006, 65438+1October 65438+June, the 2 1 World Conference on Fusion Energy (IAEA) called "Nuclear Fusion Olympics" was held in Chengdu (left). The World Conference on Fusion Energy is the highest level academic conference in the field of international nuclear fusion research. It is held every two years, which is the first time in developing countries. More than 800 Chinese and foreign scientists, including Professor Burkardt, Deputy Director General of the International Atomic Energy Agency and Chairman of the International Fusion Research Council, attended the meeting. At previous IAEA meetings, only three tokamaks, JET in Europe, DIII-D in America and JT-60U in Japan, were listed in the first part of the report. Wan Yuanxi, general manager of EAST, made the first key explanation at this meeting, which shows that the international fusion community is highly concerned about the first fully superconducting tokamak EAST. After the report, the audience stood up and applauded warmly, which was the first time in the history of the fusion energy conference. During the meeting, many foreign research institutions and universities expressed their strong willingness to cooperate with EAST, reached more than ten bilateral cooperation projects and signed bilateral cooperation agreements. Chairman Lu's congratulatory letter pointed out that the first discharge experiment of the EAST nuclear fusion experimental device of the fully superconducting noncircular cross-section tokamak marked a new stage of the EAST device engineering experiment, and also showed that Chinese scientists and technicians had the ability to independently realize the construction and operation of a large-scale scientific engineering experimental device with international advanced level. EAST will provide a new experimental platform for nuclear fusion research in China and even the world.
At 23: 00 June, 65438+2007 1 October14-1June, 5, EAST discharged four times continuously, with a single time of about 50 milliseconds, and the second round of physical experiments began. The main goal of this experiment is not to pursue the length of discharge time, but to obtain non-circular cross-section plasma on the basis of circular cross-section plasma obtained in 2006, which is of great significance.
On June 29th, 2007, Science and Technology Herald, a core periodical of science and technology under China Association for Science and Technology, selected 14 projects in Beijing, such as the completion of EAST device and the successful development of Taihang engine, and the acceptance of Qinshan Phase II nuclear power plant.
On February 15, 2007, the Basic Research Management Center of the Ministry of Science and Technology and the Academic Department of China Association for Science and Technology announced the results of the "Top Ten News of Basic Research in China" in 2006, and the EAST project was selected for its originality, news and extensive social influence.
On March 1 day, 2007, EAST successfully passed the national acceptance. The National Development and Reform Commission hosted the acceptance meeting of the Eastern countries in Hefei (left). The acceptance committee listened to the opinions of project construction, expert inspection, expert appraisal and pre-acceptance of Chinese Academy of Sciences, reviewed the acceptance materials of related disciplines, and inspected the EAST device on the spot. It is agreed that the technical process of the project meets the design requirements, and the main engine and its subsystems meet or exceed the design indicators. It is the first fully superconducting non-circular cross-section tokamak nuclear fusion experimental device successfully operated in the world. The project has completed the construction task with high quality in an all-round way, reached the predetermined index, and agreed that the project passed the national acceptance.
In April 2007 10, the project of "Sino-US Joint Research on Advanced Operation Mode of Tokamak" undertaken by Plasma passed the acceptance (right), and Southwest Institute of Physics of Nuclear Industry participated in this project. The acceptance expert group reviewed the project acceptance materials, listened to the project implementation summary report, and conducted on-site investigation and consultation. The expert group thinks that the project has fully completed the contents stipulated in the contract and achieved the expected goal, agrees that the project has passed the acceptance, and suggests that the project undertaker should adhere to effective international cooperation methods and expand the scope of cooperation, hoping to get further support from relevant departments. The implementation of this project has effectively utilized the scientific and technological resources of magnetic confinement fusion in the United States, mastered the key technologies such as diagnosis, numerical simulation and control, solved some bottleneck problems restricting the research of magnetic confinement fusion in China, improved the technical and physical research level in the field of nuclear fusion in China, shortened the gap with international fusion research, trained a group of urgently needed talents in the field of magnetic confinement fusion, exercised the team, and laid a good foundation for wider international cooperation.
On August 27th, 2007, the eastern batch of KU-2.45 microwave klystron in ISTOK Institute of Russia passed the acceptance test successfully (left).
On February 3rd, 2007, 65438+, after several months' efforts, the internal components of EAST have been reconstructed, including the installation of heating sleeve, boride water pipe, single-ring fixed bracket at high field side, ultrasonic flaw detection of heat sink materials, trial installation of heat sink bracket and simulated heat sink on simulated116 tooling, heat sink molding, opening and cooling water pipe.
On June 365438+February 3, 20071day, the pre-assembly project of East Inner Component116 passed the acceptance. 116 segment pre-assembly adopts 1: 1 to truly simulate the whole installation process of heat sink components and cooling water pipes in the east vacuum chamber (right). This pre-installation verifies the rationality and practicability of the process, process, tooling and tools for the reconstruction and installation of the internal components of EAST vacuum chamber.
On March 26th, 2008, good news came from the 2008 annual work conference of China Academy of Sciences, and the research group of Dongda University won the 2007 outstanding scientific and technological achievement award of China Academy of Sciences.
On April 23-24, 2008, ITER's most important business meeting-IO (international organization) -DA (domestic organization) coordination meeting was held in the plasma institute (left). Norbert Holtkamp, First Deputy Director General of ITER International Group, TADA Rongjie, Director of ITER Project Office, and other senior representatives of ITER International Organization presided over the meeting. Senior representatives from China, the European Union, India, Japan, South Korea, Russia and the United States attended the meeting. This meeting is a regular meeting for IO to communicate and coordinate major issues with DA leaders of member countries. The meeting informed and discussed major design changes and reviews, informed and studied the suggestions of STAC and TAG meetings, discussed and prepared the report submitted to ITER board of directors, and discussed the planning progress, resource planning and fund adjustment of procurement packages in various countries. The delegates visited the Oriental Installation and the ITER CICC pipeline crossing project under construction.
On May 12, 2008, Director Li Jiangang of the Institute of Plasma announced the successful completion of the installation of the internal components of the vacuum chamber of the EAST device. The installation of internal components of vacuum chamber involves nine major projects, involving more than 59,000 parts. The installation project started on 2008 1 month 14 and ended on May 8, 2008. After more than three months' efforts, the installation task of the internal components of the vacuum chamber of the EAST device was successfully completed with its high quality and high speed. This is the first major project since the establishment of Dongfang Installation.
On February 3, 2008, 65438, the secondary reconstruction project of the east inner member was completely completed and passed the acceptance test smoothly. The relevant departments made a work report, and introduced the sincere cooperation between the responsible engineer and the construction unit and the concerted efforts of Qi Xin, which broke through a number of technical difficulties in tackling key problems, formulated safe, reliable and feasible solutions and strictly implemented them. (The picture on the right shows the reformed vacuum chamber. ) The renovation project started in June+10/October, 65438+March, lasting 53 days, involving mechanical installation, vacuum leak detection, collimation measurement and other specialties. Thanks to the efforts of giant energy company, science company, general design room and six rooms, this glorious and arduous project was finally completed with high quality and high speed seven days ahead of schedule. This renovation of internal components is not a simple installation repetition, but a tough technical battle. Important breakthroughs have been made in lock fastening, displacement measurement, graphite tile renovation, disassembly and maintenance, etc., which have accumulated valuable engineering practice for future work. Experts attending the meeting fully affirmed the quality and speed of the renovation project, spoke highly of the good cooperative research and quality management in the renovation process, and put forward hopes and requirements for all aspects of work. The meeting adopted the acceptance opinions of the renovation project.
In June 2009, 5438+065438+1October 13, the sub-project of EAST/HT-7 cryogenic system reconstruction project "liquid nitrogen transmission line reconstruction project" was successfully completed, and the liquid nitrogen transmission function has been successfully realized. The span of the reconstructed liquid nitrogen transmission line is about150m (about 30m before reconstruction). The longer the transmission line is, the more difficult it is to cause gas blockage, liquid leakage and vacuum pumping. The maximum drop of the transformed infusion pipeline is close to 10 m (from ditch to bridge), which is easy to cause problems such as gas resistance and high consumption of liquid nitrogen transportation.