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 This paper describes the use of a 1P801 SBC in the investigation on thermoluminescence and temperature dependence of luminescence to fulfil the requirement of automatic temperature control and automatic measurement of physical parameters. The system may acts as a constant temperature controller in order to study the relations between luminescence characteristic and temperature. It also may give heating rates of 4℃/min, 6℃/min,10℃/ min and 12℃/min in order to study the depth of trap level and their dis tribution... This paper describes the use of a 1P801 SBC in the investigation on thermoluminescence and temperature dependence of luminescence to fulfil the requirement of automatic temperature control and automatic measurement of physical parameters. The system may acts as a constant temperature controller in order to study the relations between luminescence characteristic and temperature. It also may give heating rates of 4℃/min, 6℃/min,10℃/ min and 12℃/min in order to study the depth of trap level and their dis tribution in samples. In addition, the computer may carry out the measurement of luminescence intensity and the calculation of the depth of trap level.Adopting computer Direct .Digital Control (DDC) and Sequence Control Counter (SCC), the system is flexible for changing or increasing its functions.This can be done simply by changing the system software.Fig.1 is the schematic diagram of physical experiment system. Fig.2 is the block diagram of computer control system.Adopting access form of temperature table, in the design of software, we are relieved from the tedious correction of experimental result.It is easy to change the temperature table when the thermocouple is changed.Z80CTC is programed as a timer interrupting the Z80CPU at time intervals desired and the Z80CPU performs service programs once every interruption (controlling algorithm and measuring program etc.).It is the time base of linear heating. Having separated PD from PID by using algorithm logic in PID algorithm, we get an advantage that the overcorrections of variable to be controlled are decreased and the times to reach stabilization are shortened.In the design of hardware, interface circuits are suitable to different heating systems and multiparameter measurement. The measured thermoluminescence curve may be printed by TP801P microprinter and displayed on an oscilloscope. The realtime temperature and the deviation of the control system are displayed by LED (light emitting diode) of TP801. With these universal interface circuits, the system may be used in other experimental systems which need temperature controlling, multichannel measuring and general calculates.The sampling and middle value filter subroutines as well as the main program flow chart are recommended in this paper (see Fig.3,4,5). Incremental value equation of PID algorithm is also suggested.Fig.6, Fig.7 and Fig.8 are the examples of experimental curves. Fig.6 is the thermoluminescence curve of ZnS: Cu,Co which is measured with the temperature of the system automatically controlled (above room temperature) and printed by TP801P microprinter. Fig.7 is the thermoluminescence curve of the same sample which is measured with the manual temperature control and plotted on a XY recorder. Comparing these two curves, we can see that the resolution of trap energy spectrum is improved when heating rate is controlled by the computer. Fig. 8 is the emission spectra cf Y2O2S:Eu (1×104) at different constant, temperatures which are controlled by the computer. The curves were plotted on a XY recorder.  在热释光(TL)和发光温度特性研究中引入TP80l单板计算机,使其完成对加热系统的温度的实时控制和物理参数的自动测量等工作。该系统除可作一般的恒稳控制以研究样品的发光性能对温度的依赖关系,也可在0℃～160℃范围内给出不同的升温速率以研究不同升温速率下样品的陷阱深度及分布情况。与此同时,计算机将完成测量光强、计算陷阱能级深度和打印热释光曲线的功能。本文对系统的硬件及软件设计作了较详细的介绍。  Introduced is a new method of PID selftuning for DDC systems based on critical proportion band approach, where the system is forced to maintain a constantamplitude oscillation by a software embodying relay element performance that dead zone as well as hysterisis characteristics is not likely discerned with. Evaluation of parameters at critical oscillations can be obtained by measuring the amplitudes and the periods therein; and, according to the expanded critical proportion band method, evaluation of PID parameters... Introduced is a new method of PID selftuning for DDC systems based on critical proportion band approach, where the system is forced to maintain a constantamplitude oscillation by a software embodying relay element performance that dead zone as well as hysterisis characteristics is not likely discerned with. Evaluation of parameters at critical oscillations can be obtained by measuring the amplitudes and the periods therein; and, according to the expanded critical proportion band method, evaluation of PID parameters can readily be worked out and bestowed on the PID algorithm to render selftuning.  本文介绍一种在DDC控制中用计算机实现的PID参数自整定的方法。此法基于扩充临界比例度法,通过软件实施一个无滞环、无死区的继电特性,使系统产生等幅振荡。通过测取振荡波形的振幅和周期,求取系统临界振荡的参数。根据扩充临界比例度法计算出PID之参数,並通过程序自动赋于PID调节程序,以达到自动整定和投运之目的。  Using the ITAE criterion as a performance index,the method is presented for obtaining optimum tuning parameters of the PID algorithm expressions of main loop and viceloop in the direct digital cascade control systems through the use of simplex method and step by step approximation method.This method is accurate,reliable,convenient and easy to grasp.It presents direct digital cascade control systems with a set of optimum tuning parameters.Because researched object is a firstorder time delay moder with universality... Using the ITAE criterion as a performance index,the method is presented for obtaining optimum tuning parameters of the PID algorithm expressions of main loop and viceloop in the direct digital cascade control systems through the use of simplex method and step by step approximation method.This method is accurate,reliable,convenient and easy to grasp.It presents direct digital cascade control systems with a set of optimum tuning parameters.Because researched object is a firstorder time delay moder with universality in process control, the method has practical significance.The method with optimization is given for optimization design ofp arameters of cascade control systems.  本文以 ITAE 积分准则为性能指标,提出了采用单纯形寻优技术和遂步逼近法选择直接数字串级控制系统主、副回路 PID 算式中最佳整定参数的方法。该方法准确、可靠、方便,而且容易掌握,可为直接数字串级控制系统提供一组最佳整定参数。由于所研究的对象是带纯滞后的一阶惯性参数模型,在过程控制中具有普遍性,所以该方法具有实用意义。文中提供了用最优化技术进行串级控制系统的参数最优化设计的一种方法。   << 更多相关文摘 



