原油蒸馏是石化生产中的重要生产环节,它的生产水平直接影响到整个企业对原油的使用效率和经济效益。目前,在原油蒸馏过程中,多采用集散控制系统(distributed control system,DCS)。但为适应国内外市场竞争要求,提高经济效益,本文针对...原油蒸馏是石化生产中的重要生产环节,它的生产水平直接影响到整个企业对原油的使用效率和经济效益。目前,在原油蒸馏过程中,多采用集散控制系统(distributed control system,DCS)。但为适应国内外市场竞争要求,提高经济效益,本文针对新疆某石化厂原油蒸馏装置设计了一套现场总线控制系统(fieldbus control system,FCS)。阐述了选择FCS的原因,给出了系统结构图,并详细说明了FCS的设计方案。采用了这套FCS后,显著提高了该厂的经济效益并保证了装置的安全平稳运行。展开更多
Aiming at the comparatively laggard level of power plant electrical system automation, this paper analyzes the feasibility,necessity and some key points of the application of integrated automation technology to power ...Aiming at the comparatively laggard level of power plant electrical system automation, this paper analyzes the feasibility,necessity and some key points of the application of integrated automation technology to power plant electrical system. New idea using fieldbus control system technology is presented. This paper also gives the outline and detailed schemes.展开更多
A networked control and supervision system (NCSS) based on LonWorks fieldbus and lntranet/Intemet was designed, which was composed of the universal intelligent control nodes (ICNs), the visual control and supervis...A networked control and supervision system (NCSS) based on LonWorks fieldbus and lntranet/Intemet was designed, which was composed of the universal intelligent control nodes (ICNs), the visual control and supervision configuration platforms (VCCP and VSCP) and an Intranet/Internet-based remote supervision platform (RSP). The ICNs were connected to field devices, such as sensors, actuators and controllers. The VCCP and VSCP were implemented by means of a graphical programming environment and network management so as to simplify the tasks of programming and maintaining the ICNs. The RSP was employed to perform the remote supervision function, which was based on a three-layer browser/server(B/S) structure mode. The validity of the NCSS was demonstrated by laboratory experiments.展开更多
In order to build a power plant with high efficiency,low investment and zero warm water discharge,a series of innovations are applied to the two 1 000-MW units of Ninghai Power Plant.The new technologies include the c...In order to build a power plant with high efficiency,low investment and zero warm water discharge,a series of innovations are applied to the two 1 000-MW units of Ninghai Power Plant.The new technologies include the closed-circuit system for seawater cooling tower with a spraying area of 13 000 m2,the main buildings with reinforced concrete structure,the plasma ignition system for tower boiler and the fieldbus control system.Optimization measures are taken in some aspects,such as the open point of the turbine overload valves,the boiler dimensions,the technical process,the electric system,the building structures and the layout of the power plant.The units have been running for more than half a year with the thermal efficiency as high as 45.79% and without warm water discharged,which indicates that all the systems are safe and steady and the original purpose of optimization has been realized.展开更多
This paper briefly states the features and advantages of FCS (fieldbus control system). In view of condensate water fined processing system of domestic 600 MW supercritical coal-fired generating units, it designed a...This paper briefly states the features and advantages of FCS (fieldbus control system). In view of condensate water fined processing system of domestic 600 MW supercritical coal-fired generating units, it designed and developed a FCS for entirely process control, designed computer monitoring software and organized network monitor the change of data. At the same time, making the simulation device of the system, the FCS control system scheme is implemented on this device. It is verified by practice that the system control technology is advanced, safe, reliable and operation well. It provides a complete project for automation technology upgrade program in power plant. In addition, this device can be used in the power industry technical personnel training and teaching of colleges and universities. It is worth promotion and reference.展开更多
Communication based train control systems (CBTC) must work even in the worst situation-- train crossing. This paper models the propagation characteristics in one of the most common and piv- otal scenarios--train cro...Communication based train control systems (CBTC) must work even in the worst situation-- train crossing. This paper models the propagation characteristics in one of the most common and piv- otal scenarios--train crossing in subway tunnels which is rarely mentioned in previous publications. Firstly, measurements for train crossing scenario at 2.4 GHz in a real subway line in Madrid have been made. The field measurement is the most reliable way to reveal the propagation characteristics involving shadowing effect and fast fading. Moreover, to precisely describe the fast fading distribu- tion and eliminate the inevitable weak points of traditional fitting way, a best numerical approxima- tion method using Legendre orthogonal polynomials has been proposed. Comparisons show that this method works better and is of greater physical significance. Finally, a complete statistical model is given and all the coefficients can be applied by system designers for the link and system level simu- lations.展开更多
In order to solve effectively the problems of deep mining with safety and high efficiency, the multi- pie factors influencing the stability of deep rock roadway and technical problems are analyzed in the light of the ...In order to solve effectively the problems of deep mining with safety and high efficiency, the multi- pie factors influencing the stability of deep rock roadway and technical problems are analyzed in the light of the severe situation of effective mining for deep coal resource, and the stability control methods for deep rock road- way are provided, which are based on the idea of combined support with separated steps and integral control of surrounding rock of deep rock roadway. The suggested methods were applied to a deep rock roadway with -648 m depth in Gubei coal mine of Huainan area. The field test was carried out and the in-situ monitoring was imple- mented, and the support scheme was optimized and adjusted to improve the stability of the surrounding rock of the roadway based on the feedback analysis. The results showed that the stability can be improved greatly by the provided control methods tbr deep roadway. The present methods lbr stability control of deep rock roadway can be used to other deep rock roadways with the similar conditions.展开更多
Since wind power has the features of being intermittent and unpredictable, and usually needs transmission over long distances, grid integration of large-scale wind power will exert signif icant influence on power grid...Since wind power has the features of being intermittent and unpredictable, and usually needs transmission over long distances, grid integration of large-scale wind power will exert signif icant influence on power grid planning and construction, and will make a heavy impact on the safe and reliable operation of power systems. To deal with the diff iculties of large scale wind power dispatch, this paper presents a new automatic generation control (AGC) scheme that involves the participation of wind farms. The scheme is based on ultra-short-term wind power forecast. The author establishes a generation output distribution optimization mode for the power system with wind farms and verif ies the feasibility of the scheme by an example.展开更多
If a coherent perturbation field is used to couple the excited level of the coupling transition in the five-level K-type atom with another higher excited level, the two-photon electromagnetically induced transparency ...If a coherent perturbation field is used to couple the excited level of the coupling transition in the five-level K-type atom with another higher excited level, the two-photon electromagnetically induced transparency can be locally modulated by altering the parameters of the additional perturbation field. With different detunings of the coherent perturbation field, the absorption peak or transparency window with sharp and high-contrast speetrM feature can be generated in the two-photon absorption spectrum. The physical interpretation of these phenomena is given in terms of the dressed states.展开更多
文摘原油蒸馏是石化生产中的重要生产环节,它的生产水平直接影响到整个企业对原油的使用效率和经济效益。目前,在原油蒸馏过程中,多采用集散控制系统(distributed control system,DCS)。但为适应国内外市场竞争要求,提高经济效益,本文针对新疆某石化厂原油蒸馏装置设计了一套现场总线控制系统(fieldbus control system,FCS)。阐述了选择FCS的原因,给出了系统结构图,并详细说明了FCS的设计方案。采用了这套FCS后,显著提高了该厂的经济效益并保证了装置的安全平稳运行。
文摘Aiming at the comparatively laggard level of power plant electrical system automation, this paper analyzes the feasibility,necessity and some key points of the application of integrated automation technology to power plant electrical system. New idea using fieldbus control system technology is presented. This paper also gives the outline and detailed schemes.
基金Project (60425310) supported by the National Natural Science Foundation of ChinaProject(2006AA04Z172) supported by the High-TechResearch and Development Program of China
文摘A networked control and supervision system (NCSS) based on LonWorks fieldbus and lntranet/Intemet was designed, which was composed of the universal intelligent control nodes (ICNs), the visual control and supervision configuration platforms (VCCP and VSCP) and an Intranet/Internet-based remote supervision platform (RSP). The ICNs were connected to field devices, such as sensors, actuators and controllers. The VCCP and VSCP were implemented by means of a graphical programming environment and network management so as to simplify the tasks of programming and maintaining the ICNs. The RSP was employed to perform the remote supervision function, which was based on a three-layer browser/server(B/S) structure mode. The validity of the NCSS was demonstrated by laboratory experiments.
文摘In order to build a power plant with high efficiency,low investment and zero warm water discharge,a series of innovations are applied to the two 1 000-MW units of Ninghai Power Plant.The new technologies include the closed-circuit system for seawater cooling tower with a spraying area of 13 000 m2,the main buildings with reinforced concrete structure,the plasma ignition system for tower boiler and the fieldbus control system.Optimization measures are taken in some aspects,such as the open point of the turbine overload valves,the boiler dimensions,the technical process,the electric system,the building structures and the layout of the power plant.The units have been running for more than half a year with the thermal efficiency as high as 45.79% and without warm water discharged,which indicates that all the systems are safe and steady and the original purpose of optimization has been realized.
文摘This paper briefly states the features and advantages of FCS (fieldbus control system). In view of condensate water fined processing system of domestic 600 MW supercritical coal-fired generating units, it designed and developed a FCS for entirely process control, designed computer monitoring software and organized network monitor the change of data. At the same time, making the simulation device of the system, the FCS control system scheme is implemented on this device. It is verified by practice that the system control technology is advanced, safe, reliable and operation well. It provides a complete project for automation technology upgrade program in power plant. In addition, this device can be used in the power industry technical personnel training and teaching of colleges and universities. It is worth promotion and reference.
基金Supported by the National Natural Science Foundation of China(No.60830001)Program for New Century Excellent Talents in University(No.NCET-09-0206)+2 种基金the Key Project of State Key Lab.of Rail Traffic Control and Safety(No.RCS2008ZZ006)Program for Changjiang Scholars and Innovative Research Team in University(No.IRT0949)the Project of State Key Lab.of Rail Traffic Control and Safety(No.RCS2008ZT005)
文摘Communication based train control systems (CBTC) must work even in the worst situation-- train crossing. This paper models the propagation characteristics in one of the most common and piv- otal scenarios--train crossing in subway tunnels which is rarely mentioned in previous publications. Firstly, measurements for train crossing scenario at 2.4 GHz in a real subway line in Madrid have been made. The field measurement is the most reliable way to reveal the propagation characteristics involving shadowing effect and fast fading. Moreover, to precisely describe the fast fading distribu- tion and eliminate the inevitable weak points of traditional fitting way, a best numerical approxima- tion method using Legendre orthogonal polynomials has been proposed. Comparisons show that this method works better and is of greater physical significance. Finally, a complete statistical model is given and all the coefficients can be applied by system designers for the link and system level simu- lations.
文摘In order to solve effectively the problems of deep mining with safety and high efficiency, the multi- pie factors influencing the stability of deep rock roadway and technical problems are analyzed in the light of the severe situation of effective mining for deep coal resource, and the stability control methods for deep rock road- way are provided, which are based on the idea of combined support with separated steps and integral control of surrounding rock of deep rock roadway. The suggested methods were applied to a deep rock roadway with -648 m depth in Gubei coal mine of Huainan area. The field test was carried out and the in-situ monitoring was imple- mented, and the support scheme was optimized and adjusted to improve the stability of the surrounding rock of the roadway based on the feedback analysis. The results showed that the stability can be improved greatly by the provided control methods tbr deep roadway. The present methods lbr stability control of deep rock roadway can be used to other deep rock roadways with the similar conditions.
文摘Since wind power has the features of being intermittent and unpredictable, and usually needs transmission over long distances, grid integration of large-scale wind power will exert signif icant influence on power grid planning and construction, and will make a heavy impact on the safe and reliable operation of power systems. To deal with the diff iculties of large scale wind power dispatch, this paper presents a new automatic generation control (AGC) scheme that involves the participation of wind farms. The scheme is based on ultra-short-term wind power forecast. The author establishes a generation output distribution optimization mode for the power system with wind farms and verif ies the feasibility of the scheme by an example.
基金Supported by National Natural Science Foundation of China under Grant Nos.10775100 and 10974137
文摘If a coherent perturbation field is used to couple the excited level of the coupling transition in the five-level K-type atom with another higher excited level, the two-photon electromagnetically induced transparency can be locally modulated by altering the parameters of the additional perturbation field. With different detunings of the coherent perturbation field, the absorption peak or transparency window with sharp and high-contrast speetrM feature can be generated in the two-photon absorption spectrum. The physical interpretation of these phenomena is given in terms of the dressed states.