This paper describes the detailed desi gn of data acquisition device with multi-channel and high-precision for aerosp ace.Based on detailed analysis of the advantages and disadvantages of tw o common acquisition circu...This paper describes the detailed desi gn of data acquisition device with multi-channel and high-precision for aerosp ace.Based on detailed analysis of the advantages and disadvantages of tw o common acquisition circuits,the design factors of acquisition device focus o n accuracy,sampling rate,hardware overhead and design space.The me chanical structure of the system is divided into different card layers according to different functions and the structure has the characteristics of high reliability,conveni ence to install and scalability.To ens ure reliable operation mode,the interface uses the optocoupler isolated from th e e xternal circuit.The transmission of signal is decided by the current in the cur rent loop that consists of optocouplers between acquisition device and t est bench.In multi-channel switching circuit,by establ ishing analog multiplexer model,the selection principles of circuit modes are given.展开更多
The popularization of large scale central air conditioning system (CACS) has brought forward a new pro blem,i.e. how to measure the cooling and heating quantum accurately. This problem will directly affect the qua ...The popularization of large scale central air conditioning system (CACS) has brought forward a new pro blem,i.e. how to measure the cooling and heating quantum accurately. This problem will directly affect the qua lity of modern property management. So the study on the technology of measuring heat and cool is very necessary. In this paper, the detailed thermal analysis and the mathematical model of relative parameters that affect the measurement of heat and cool are discussed. A sample instrument based on the model is made, After the trial use by several customers, the device is proved to be practical, worthwhile and of good capacity.展开更多
In this paper, the measurement method of calorimetric power for an electron cyclotron resonance heating(ECRH) system for EAST is presented. This method requires measurements of the water flow through the cooling cir...In this paper, the measurement method of calorimetric power for an electron cyclotron resonance heating(ECRH) system for EAST is presented. This method requires measurements of the water flow through the cooling circuits and the input and output water temperatures in each cooling circuit. Usually, the inlet water temperature stability is controlled to obtain more accurate results.The influence of the inlet water temperature change on the measurement results is analyzed for the first time in this paper. Also, a novel temperature calibration method is proposed. This kind of calibration method is accurate and effective, and can be easily implemented.展开更多
A measurement system was designed to measure the railgun's parameters in launching process,which includes Rogowski coil sensor for measuring rail's current,B-dot probe for obversing projectile's velocity i...A measurement system was designed to measure the railgun's parameters in launching process,which includes Rogowski coil sensor for measuring rail's current,B-dot probe for obversing projectile's velocity in bore,net target for catching muzzle velocity,signal condition circuit and high-speed data acquisition card for analyzing and storing data.Its software was also developed in WINDOWS operational environment via modularized design.The designed sensors and test software were successfully used in a practical electromagnetic railgun system to monitor the process of launching.The test results indicate that the state of launching can be intuitively observed and the parameters are accurately acquired and recorded.The software design method can shorten the development cycle,enhance the system's flexibility and provide the interface for the secondary development.The system shows great reliability.It is an effective and practical measurement platform for further research on the electromagnetic launch system.展开更多
[目的]文章旨在研究空中风力发电系统(Airborne Wind Energy System,AWES)的测风需求及设备选型。[方法]以某空中风力发电示范工程为依托,开展测风激光雷达与风廓线雷达的对比观测试验,并对数据获取率、垂直廓线特征和时间变化特征进行...[目的]文章旨在研究空中风力发电系统(Airborne Wind Energy System,AWES)的测风需求及设备选型。[方法]以某空中风力发电示范工程为依托,开展测风激光雷达与风廓线雷达的对比观测试验,并对数据获取率、垂直廓线特征和时间变化特征进行分析。[结果]结果显示:在3 km高度范围内,测风激光雷达的数据获取率随高度递减至不足0.4,风廓线雷达的数据获取率则维持在0.98以上,具有更好的观测适应性;两种测风设备的风速、风向垂直廓线以及逐日、多日波动特征均具有一致性,并且能被再分析资料和高空气象站同期探空资料所验证。测风激光雷达观测结果的中位数、极差、标准差等统计特征与再分析资料更接近,相关性更好;风廓线雷达观测结果的极差和标准差整体偏大,测风精度不及测风激光雷达。[结论]文章研究表明,应根据项目所在地的气候状况,在空中风力发电站工程的不同设计阶段合理选择测风设备,科学设置测风方式。展开更多
基金National Natural Science Foundation of China (No.50905169)
文摘This paper describes the detailed desi gn of data acquisition device with multi-channel and high-precision for aerosp ace.Based on detailed analysis of the advantages and disadvantages of tw o common acquisition circuits,the design factors of acquisition device focus o n accuracy,sampling rate,hardware overhead and design space.The me chanical structure of the system is divided into different card layers according to different functions and the structure has the characteristics of high reliability,conveni ence to install and scalability.To ens ure reliable operation mode,the interface uses the optocoupler isolated from th e e xternal circuit.The transmission of signal is decided by the current in the cur rent loop that consists of optocouplers between acquisition device and t est bench.In multi-channel switching circuit,by establ ishing analog multiplexer model,the selection principles of circuit modes are given.
文摘The popularization of large scale central air conditioning system (CACS) has brought forward a new pro blem,i.e. how to measure the cooling and heating quantum accurately. This problem will directly affect the qua lity of modern property management. So the study on the technology of measuring heat and cool is very necessary. In this paper, the detailed thermal analysis and the mathematical model of relative parameters that affect the measurement of heat and cool are discussed. A sample instrument based on the model is made, After the trial use by several customers, the device is proved to be practical, worthwhile and of good capacity.
基金supported by the National Magnetic Confinement Fusion Science Program of China (Grant Nos.2011GB102000, 2015GB103000)
文摘In this paper, the measurement method of calorimetric power for an electron cyclotron resonance heating(ECRH) system for EAST is presented. This method requires measurements of the water flow through the cooling circuits and the input and output water temperatures in each cooling circuit. Usually, the inlet water temperature stability is controlled to obtain more accurate results.The influence of the inlet water temperature change on the measurement results is analyzed for the first time in this paper. Also, a novel temperature calibration method is proposed. This kind of calibration method is accurate and effective, and can be easily implemented.
基金Sponsored by the 863 National High Technology Research and Development Program of China
文摘A measurement system was designed to measure the railgun's parameters in launching process,which includes Rogowski coil sensor for measuring rail's current,B-dot probe for obversing projectile's velocity in bore,net target for catching muzzle velocity,signal condition circuit and high-speed data acquisition card for analyzing and storing data.Its software was also developed in WINDOWS operational environment via modularized design.The designed sensors and test software were successfully used in a practical electromagnetic railgun system to monitor the process of launching.The test results indicate that the state of launching can be intuitively observed and the parameters are accurately acquired and recorded.The software design method can shorten the development cycle,enhance the system's flexibility and provide the interface for the secondary development.The system shows great reliability.It is an effective and practical measurement platform for further research on the electromagnetic launch system.
文摘[目的]文章旨在研究空中风力发电系统(Airborne Wind Energy System,AWES)的测风需求及设备选型。[方法]以某空中风力发电示范工程为依托,开展测风激光雷达与风廓线雷达的对比观测试验,并对数据获取率、垂直廓线特征和时间变化特征进行分析。[结果]结果显示:在3 km高度范围内,测风激光雷达的数据获取率随高度递减至不足0.4,风廓线雷达的数据获取率则维持在0.98以上,具有更好的观测适应性;两种测风设备的风速、风向垂直廓线以及逐日、多日波动特征均具有一致性,并且能被再分析资料和高空气象站同期探空资料所验证。测风激光雷达观测结果的中位数、极差、标准差等统计特征与再分析资料更接近,相关性更好;风廓线雷达观测结果的极差和标准差整体偏大,测风精度不及测风激光雷达。[结论]文章研究表明,应根据项目所在地的气候状况,在空中风力发电站工程的不同设计阶段合理选择测风设备,科学设置测风方式。