Design And Research Of Ultrasonic Gas Leak Detector Based On Embedded System

People are continuously raising their demand about pressure pipeline dependability and security with the development of long-distance Oil and Gas transmission. Pipeline leak detection as an important measure to protect the safe transport of pipeline have paid more and more attention to people. The traditional air leak detection instruments of pipeline has unable to meet the requirements. Huge investment, promises no quick results and high maintenance make it hardly wide available in China. It is need to research a new testing system of pipeline air leak. The new testing system should be advanced and practical and according to the situation of China and different districts.The target of the task is designing a testing system of ultrasonic pipeline leakage based on embedded system. The testing system is able to collect and process the ultrasonic which produced by the high pressure pipeline. The signal come by analogue to digital, FFT and then display it's spectrum character on LCD screen. According to the overall needs of system designing, the design scheme based on embedded system was proposed and adopted. The kernel of embedded system is C8051F120 that is full composite SOC. It could do well in handing the collection of ultrasonic, signal analysis and FFT.The testing system adopts modular design method. It is divided into three parts, which are the collection module, signal processing module and display module. In the part of hardware, briefly introduced the characteristic of electronic elements. The implement of produced this design detailed process and the final realization electric circuit, and has analyzed the electric circuit principle of work. In the part of software, implement the design program of A/D converter, FFT and algorithm of Bresenham. In the part of test results and accuracy analysis, use air compressor simulate the scene of pressure pipeline leakage, testing the machine. validating the rationality of the experiment design and control strategy.In the thesis we have done substantial analyses and research to be aware of the pipeline air leak detection testing requirements and traditional testing means. Contrast its advantages and disadvantages and finally decide the plan. This document presents the functionality of the high-performance MCU C8051F120,design of the band-pass filter and digital image processing technology. Before the prototype was developed, system designing, hardware choosing, circuit design, schematic and PCB diagram drawing, circuit board making. hardware connection, writing programs, standard and test had to be done. Finally, the performance of pipeline air leakage was tested by the prototype, under the condition of simulation environment.The testing result was contrasted with specialized instruments. It show that the prototype have some excellences, such as accurate measuring, high precision, steady performance and ease of use, intuitive result showing and friendly interface. Therefore the testing system has wide application prospects.