Based On The Virtual Instrument The Research Of Safety Monitoring System Of Medium And Small-sized Storage-transport Vessel Of Liquefied Petroleum Gas

With the development of the computer, sensor and microelectronics technology, how to use them on monitoring, simulation and prewarning of the transportable pressure vessel has come up to be an important safety measure and the direction of development. This dissertation develop a safety monitoring system of transportable pressure vessel based on Virtual Instrument(VI) and USB technology, which synthetically refers to the VI, USB, Analog/Digital Conversion (ADC) and other related hardware and software technology.This dissertation first begins with the analysis 'of the status and foreground of the safetymonitoring system of transportable pressure vessel. The following chapter describes the basicstructure and characteristic of the transportable pressure vessel, then the safety specialty and thecorrelative monitoring theory of the storage and transportation of the liquefied petroluem gas(LPG) as well. After that the dissertation specifies the key knowledge used in it.On the base of the research and analysis of the theory and key technology, this dissertation designed the structure of the hardware and software of the entire system, and completed the hardware and the circuit board, which include the field analog signal amplification circuit and converter, that is the modulation circuit of the temperature signal, pressure signal, gas concentration signal and etc. The USB data sampling module which realizes the analog to digital conversion (ADC), digital signal processing (DSP) and communication with the computer through the USB bus is also belonged to this partThis dissertation describes the composition and implementation of the VI workbench, also the dynamic link library (DLL) and application program has been written. The DLL realizes the communication with the core-state USB driver, and receives every operation request of the application program as well. And the application program realizes the realtime display and the analysis function for the data that has been sampled. Then the communication between the hardware of data sampling and the computer, auto testing, data processing and the test-reports generating can be realized. And it also has a very convenient man-machine conversation interface.The designing has past the systematic debug, realized the safety monitoring system of the transportable pressure vessel which base on the USB and the Virtual Instrument technology.The testing device designed in the dissertation is miniaturized, low-cost, low-power-consumption and portable. The properly of the Virtual Instrument and USB made the system be used in not only the safety monitoring system of the transportable pressure vessel, but also in other safety monitoring system of the chemistry engineering by some modification and expansion.