Design and Development of Networked Measurement and Control System
|School||Harbin Institute of Technology|
|Course||Control Science and Engineering|
|Keywords||Network Signal acquisition Embedded control DSP+FPGA|
Measurement and control are two indispensable components of modernengineering science and technology. Along with the rapid development of computer,network, microelectronics and new technological achievements achieved constantly,more powerful and cost-effective approaches can be implemented in measurementand control system. Network-based virtual measuring instrument and embeddedcontrol system is the development tendency of the measurement and control system.This engineering technology achievements not only can be turned into economicbenefit quickly but also is of profound meaning in improving military technologyand industrial production level.Combining the advantages of network-based virtual instrument and embeddedcontrol technology, a system with network communication function, remote signalacquisition function and control function is designed. The system is designed tomeet the synchronization requirement of multi-controlled-plant, which has thefollowing performance index—expandability, network communication ability, largedata bandwidth, relatively wide application field. With above abilities, network-based information interaction, embedded control, virtual presentation of operationinterface could be brought to realization. Within this system, data-acquisition&control cards are the actual executors, which consist the networktopology through ethernet and manipulated by someone through the systemsoftware running on PC.The functional architecture of the data-acquisition&control card is DSP+FPGA.A industrial-control specialized floating-point processor TMS320F28335is selectedas the DSP, which possesses excellent data-processing performance and be rich ofonchip peripherals. The type of FPGA is EP2C8Q208CN, which is of large mountof on-chip logic elements and cost effective. The core controller DSP is in charge ofmission flow control, task allocation and system harmonization which mainlyincludes algolithm operation, missions dispatch, ethernet communication etc. Theobligations of FPGA are to extend interfaces with peripheral functional modulessuch as feedback signal input, control signal output, data latching. In addition,FPGA can receive data process mission from DSP and be implanted digital signalprocessing IP cores while some complex algorithms operation in need.The system software consists of real time monitoring module, background data-processing module, network service module. They three are not only closelyinterrelated but also relatively independent. Network service module is the bridgeof the communication between local data-acquisition&control endpoints and theother two modules. Real time monitoring module is the core of the system softwareand possesses the right to dominate the other two modules, and it is the interface toexpress functional requirement by operators. Background data-processing modulemanages system data through file-featured database and is controlled by themonitoring module.Finally, interconnect the system software and several local data-acquisition&control endpoints to carry out system test, the results show that systemcan perfectly fulfil the tasks got from the operators and meet the design aims andneeds primely.