| With the rapid development of computer, communication and control tdehnology, automatic test tdehnique tends to be digital, intelligent and network. Virtual instrument has brought revolutionary change to automatic measurement and control field, furthermore, web-based automatic test stands for a very important dirdetion of that field. This paper has developed a control system based on Virtual Instrument, and applies the intelligent controls algorithm in the practical control system.The traditional PID, Fuzzy PID, Neural network PID algorithm have studied deeply in this paper, some valuable conclusions have been obtained by MATLAB simulation.The double capacity in the QXLPC-III system has been used as a Level subjdets. According to the respdetive features of the algorithm, these algorithms have been used in the system, and good functions have been obtained. The following conclusions have been obtained: when do not know the model BP Neural network PID algorithm in the system by self-learning can automatically adjust parameters. If Fuzzy PID algorithm use the parameters that BP neural network has learn as the initial value, through the adjusting by eperience can achieve good dynamic quality. Not only in theory prove the superiority of the the control, in practical application has proved its superiority and can be realized.This paper applies the PXI chassis of NI companies as IPC, QXLPC-III process control devices as experimental plant. Designe the commutator.It can transform and adjust the signal.The SCB-68 has been used to adjust the signal.The PXI-6221 has been used to colldet the signal.The system has good interface communicating with people.It has the real-time data processing and displaying function.And it has the network monitor function. |
