The control system for the Experimental Advanced Superconductive Tokamak （EAST） cryogenic system is designed and constructed based on Delta-V DCS （Distribution Control System）, which consists of engineering workst...The control system for the Experimental Advanced Superconductive Tokamak （EAST） cryogenic system is designed and constructed based on Delta-V DCS （Distribution Control System）, which consists of engineering workstations, operator workstations, application workstations, redundant controller units, input/output （I/O） cards and a redundant control network. Our task is to design a supervisory and control system to provide the operator interface for control and monitoring, sending alarms, archiving of selected signals, and other routines to analyze realtime and historic data. The hardware configuration, software structure and control algorithms are illustrated in detail in this paper. Hvpothetic oroblems and further research are also mentioned.展开更多
Disruption remains to be a serious threat to large tokamaks like the International Thermonuclear Experimental Reactor(ITER).The injection speed of disruption mitigation systems(DMS)driven by high pressure gas is limit...Disruption remains to be a serious threat to large tokamaks like the International Thermonuclear Experimental Reactor(ITER).The injection speed of disruption mitigation systems(DMS)driven by high pressure gas is limited by the sound speed of the propellant gas.When extrapolating to ITER-like tokamaks,long overall reaction duration and shallow penetration depth due to low injection speed make it stricter for plasma control system to predict the impending disruptions.Some disruptions with a short warning time may be unavoidable.Thus,a fast time response and high injection speed DMS is essential for large scale devices.The electromagnetic pellet-injection(EMPI)system is a novel massive material injection system aiming to provide rapid and effective disruption mitigation.Based on the railgun concept,EMPI can accelerate the payload to over 1000 m/s and shorten the overall reaction time to a few milliseconds.To verify the injection ability and stability of the EMPI,the prototype injector EMPI-1 has been designed and assembled.The preliminary test has been carried out using a 5.9 g armature to propel a dummy pellet and the results suggest that the EMPI configuration has a great potential to be the DMS of the large scale fusion devices.展开更多
The preliminary experimental results of ac plasma discharges in the CT-6B tokamak have been achieved by an active plasma current feedback system and the keys to a smooth transition through current zero and some phenom...The preliminary experimental results of ac plasma discharges in the CT-6B tokamak have been achieved by an active plasma current feedback system and the keys to a smooth transition through current zero and some phenomena related to the current reversal phase are also presented.展开更多
A 2 MW-2.45 GHz lower hybrid current drive （LHCD） system was designed, fab- ricated and installed successfully on EAST in 2008 to investigate high performance regimes and achieve a steady-state operation. The system...A 2 MW-2.45 GHz lower hybrid current drive （LHCD） system was designed, fab- ricated and installed successfully on EAST in 2008 to investigate high performance regimes and achieve a steady-state operation. The system is composed of 20 continuous wave （CW） klystron amplifiers, 4 sets of high voltage power supply, 20 standard rectangle waveguide （American National Standard, WR430） transmission lines with a length of 30 m to 40 m for each, and a multijunction grill containing 160 active （in groups of 8） and 25 passive sub-waveguides arranged in 5 rows and 4 columns. Fixed phase shifters in sub-waveguides and electronically-controlled digital phase shifters driving each klystron are used to control the radiated power spectrum of the grill. By means of LHCD, a plasma current of 150 kA to 500 kA at a central plasma density of 1×10^13 cm^-3 to 2×10^13 cm^-3 and a toroidal magnetic field of 2.0 T to 2.5 T was achieved. Both a fully non-inductive plasma current of 250 kA lasting up to 23 s and the ramp up were achieved. These results successfully demonstrated the capability of the LHCD system. The system is described in detail and the primaryexperimental results are presented.展开更多
A data service system plays an indispensable role in HT-7 Tokamak experiment. Since the former system doesn’t provide the function of timely data procession and analysis, and all client software are based on Windows,...A data service system plays an indispensable role in HT-7 Tokamak experiment. Since the former system doesn’t provide the function of timely data procession and analysis, and all client software are based on Windows, it can’t fulfill virtual fusion laboratory for remote researchers. Therefore, a new system which is simplified by three kinds of data servers and one data analysis and visualization software tool has been developed. The data servers in-clude a data acquisition server based on file system, an MDSplus server used as the central repository for analysis data, and a web server. Users who prefer the convenience of application that can be run in a Web Browser can easily access the experiment data without knowing X-Windows. In order to adjust instruments to control experiment the operators need to plot data duly as soon as they are gathered. To satisfy their requirement, an upgraded data analysis and visualization software GT-7 is developed. It not only makes 2D data visualization more efficient, but also it can be capable of processing, analyzing and displaying interactive 2D and 3D graph of raw, analyzed data by the format of ASCII, LZO and MDSplus.展开更多
In large fusion experiments, such as tokamak devices, there is a common trendfor slow control systems. Because of complexity of the plants, the so-called 'Standard Model' (SM)in slow control has been adopted o...In large fusion experiments, such as tokamak devices, there is a common trendfor slow control systems. Because of complexity of the plants, the so-called 'Standard Model' (SM)in slow control has been adopted on several tokamak machines. This model is based on a three-levelhierarchical control: 1) High-Level Control (HLC) with a supervisory function; 2) Medium-LevelControl (MLC) to interface and concentrate I/O field equipments; 3) Low-Level Control (LLC) withhard real-time I/O function, often managed by PLCs. FTU control system designed with SM concepts hasunderwent several stages of developments in its fifteen years duration of runs. The latestevolution was inevitable, due to the obsolescence of the MLC CPUs, based on VME-MOTOROLA 68030 withOS9 operating system. A large amount of C code was developed for that platform to route the dataflow from LLC, which is constituted by 24 Westinghouse Numalogic PC-700 PLCs with about 8000field-points, to HLC, based on a commercial Object-Oriented Real-Time database on Alpha/CompaqTru64platform. Therefore, we have to look for cost-effective solutions and finally a CompactPCI—Intelx86 platform with Linux operating system was chosen. A software porting has been done, taking intoaccount the differences between OS9 and Linux operating system in terms of Inter/Network ProcessesCommunications and I/O multi-ports serial driver. This paper describes the hardware/softwarearchitecture of the new MLC system, emphasizing the reliability and the low costs of the open sourcesolutions. Moreover, a huge amount of software packages available in open source environment willassure a less painful maintenance, and will open the way to further improvements of the systemitself.展开更多
Neutral beam injection （NBI） system with two neutral beam injections will be con- structed on the Experimental Advanced Superconducting Tokamak （EAST） in two stages for high power auxiliary plasmas heating and non...Neutral beam injection （NBI） system with two neutral beam injections will be con- structed on the Experimental Advanced Superconducting Tokamak （EAST） in two stages for high power auxiliary plasmas heating and non-inductive current drive. Each NBI can deliver 2-4 MW beam power with 50-80 keV beam energy in 10-100 s pulse length. Each elements of the NBI system are presented in this contribution.展开更多
基金The project supported by the National Meg-science Engineering Project of the Chinese Government
文摘The control system for the Experimental Advanced Superconductive Tokamak （EAST） cryogenic system is designed and constructed based on Delta-V DCS （Distribution Control System）, which consists of engineering workstations, operator workstations, application workstations, redundant controller units, input/output （I/O） cards and a redundant control network. Our task is to design a supervisory and control system to provide the operator interface for control and monitoring, sending alarms, archiving of selected signals, and other routines to analyze realtime and historic data. The hardware configuration, software structure and control algorithms are illustrated in detail in this paper. Hvpothetic oroblems and further research are also mentioned.
基金Project supported by the National Magnetic Confinement Fusion Energy Research and Development Program of China (Grant No. 2019YFE03010004)the National Natural Science Foundation of China (Grant Nos. 12175078, 11905077, and 51821005)
文摘Disruption remains to be a serious threat to large tokamaks like the International Thermonuclear Experimental Reactor(ITER).The injection speed of disruption mitigation systems(DMS)driven by high pressure gas is limited by the sound speed of the propellant gas.When extrapolating to ITER-like tokamaks,long overall reaction duration and shallow penetration depth due to low injection speed make it stricter for plasma control system to predict the impending disruptions.Some disruptions with a short warning time may be unavoidable.Thus,a fast time response and high injection speed DMS is essential for large scale devices.The electromagnetic pellet-injection(EMPI)system is a novel massive material injection system aiming to provide rapid and effective disruption mitigation.Based on the railgun concept,EMPI can accelerate the payload to over 1000 m/s and shorten the overall reaction time to a few milliseconds.To verify the injection ability and stability of the EMPI,the prototype injector EMPI-1 has been designed and assembled.The preliminary test has been carried out using a 5.9 g armature to propel a dummy pellet and the results suggest that the EMPI configuration has a great potential to be the DMS of the large scale fusion devices.
基金Supported by the Chinese National Advanced Technology Foundation.
文摘The preliminary experimental results of ac plasma discharges in the CT-6B tokamak have been achieved by an active plasma current feedback system and the keys to a smooth transition through current zero and some phenomena related to the current reversal phase are also presented.
基金supported by National Natural Science Foundation of China (Nos. 10805057, 10905069)the Knowledge Innovation Program of the Chinese Academy of Sciences (No. 075FCQ0127)
文摘A 2 MW-2.45 GHz lower hybrid current drive （LHCD） system was designed, fab- ricated and installed successfully on EAST in 2008 to investigate high performance regimes and achieve a steady-state operation. The system is composed of 20 continuous wave （CW） klystron amplifiers, 4 sets of high voltage power supply, 20 standard rectangle waveguide （American National Standard, WR430） transmission lines with a length of 30 m to 40 m for each, and a multijunction grill containing 160 active （in groups of 8） and 25 passive sub-waveguides arranged in 5 rows and 4 columns. Fixed phase shifters in sub-waveguides and electronically-controlled digital phase shifters driving each klystron are used to control the radiated power spectrum of the grill. By means of LHCD, a plasma current of 150 kA to 500 kA at a central plasma density of 1×10^13 cm^-3 to 2×10^13 cm^-3 and a toroidal magnetic field of 2.0 T to 2.5 T was achieved. Both a fully non-inductive plasma current of 250 kA lasting up to 23 s and the ramp up were achieved. These results successfully demonstrated the capability of the LHCD system. The system is described in detail and the primaryexperimental results are presented.
基金Supported by National Natural Science Foundation of China (No.19981303)
文摘A data service system plays an indispensable role in HT-7 Tokamak experiment. Since the former system doesn’t provide the function of timely data procession and analysis, and all client software are based on Windows, it can’t fulfill virtual fusion laboratory for remote researchers. Therefore, a new system which is simplified by three kinds of data servers and one data analysis and visualization software tool has been developed. The data servers in-clude a data acquisition server based on file system, an MDSplus server used as the central repository for analysis data, and a web server. Users who prefer the convenience of application that can be run in a Web Browser can easily access the experiment data without knowing X-Windows. In order to adjust instruments to control experiment the operators need to plot data duly as soon as they are gathered. To satisfy their requirement, an upgraded data analysis and visualization software GT-7 is developed. It not only makes 2D data visualization more efficient, but also it can be capable of processing, analyzing and displaying interactive 2D and 3D graph of raw, analyzed data by the format of ASCII, LZO and MDSplus.
文摘In large fusion experiments, such as tokamak devices, there is a common trendfor slow control systems. Because of complexity of the plants, the so-called 'Standard Model' (SM)in slow control has been adopted on several tokamak machines. This model is based on a three-levelhierarchical control: 1) High-Level Control (HLC) with a supervisory function; 2) Medium-LevelControl (MLC) to interface and concentrate I/O field equipments; 3) Low-Level Control (LLC) withhard real-time I/O function, often managed by PLCs. FTU control system designed with SM concepts hasunderwent several stages of developments in its fifteen years duration of runs. The latestevolution was inevitable, due to the obsolescence of the MLC CPUs, based on VME-MOTOROLA 68030 withOS9 operating system. A large amount of C code was developed for that platform to route the dataflow from LLC, which is constituted by 24 Westinghouse Numalogic PC-700 PLCs with about 8000field-points, to HLC, based on a commercial Object-Oriented Real-Time database on Alpha/CompaqTru64platform. Therefore, we have to look for cost-effective solutions and finally a CompactPCI—Intelx86 platform with Linux operating system was chosen. A software porting has been done, taking intoaccount the differences between OS9 and Linux operating system in terms of Inter/Network ProcessesCommunications and I/O multi-ports serial driver. This paper describes the hardware/softwarearchitecture of the new MLC system, emphasizing the reliability and the low costs of the open sourcesolutions. Moreover, a huge amount of software packages available in open source environment willassure a less painful maintenance, and will open the way to further improvements of the systemitself.
基金supported by National Natural Science Foundation of China (No. 11075188)the Chinese Academy of Sciences Knowledge Innovation Project: the study of neutral beam steady-state operation of the key technical and physical problems
文摘Neutral beam injection （NBI） system with two neutral beam injections will be con- structed on the Experimental Advanced Superconducting Tokamak （EAST） in two stages for high power auxiliary plasmas heating and non-inductive current drive. Each NBI can deliver 2-4 MW beam power with 50-80 keV beam energy in 10-100 s pulse length. Each elements of the NBI system are presented in this contribution.
