Design Of Prepaid Gas Control System

With the development of social economy,the method of billing by manual meter reading is tedious and complicated.Taking the card of CPU as the carrier,the intelligent equipment,such as domestic gas meter,electricity meter,water meter and so on,has covered completely our life.Based on the CPU,the prepaid intelligent gas meter improves effectively a large number of problems existing in the method of traditional manual meter reading.The prepaid control system of domestic natural gas adopted the method of combining with the software and hardware to explore,which took the communication technology of the Internet of things with narrow-band as the communication between terminal and PC developed by mainstream technology in the aspect of hardware design,selected the MSP430F415 as the master controller.The system chose the interface circuit of CPU card and the circuit of communication module as the major circuits of the module of peripheral circuit.The prepaid system of natural gas conformed to the modularized processing way in the aspect of software,which carried out the software design for the system and completed the corresponding functions.The realization of the prepaid function of the system needed to create the one-to-one corresponding file system of issuing card at the side of user card,carrying out the encryption processing for the data transmission at the side of card and meter by internal authentication,external authentication and 3DES algorithm,so as to ensure the security of the system of issuing card.After the completion of the system,it can be popularized in the direction of industry.The fiducial error of ultrasonic flowmeter is less than 0.65% and its measuring repeatability is less than 0.8% at the flow rate of 10?70 m~3/h.The Newton Cotes formula and the Simpson rule are used to improve the algorithm of traditional positioning formula for the leakage point in order to precisely locate the leakage point,leading to the positioning error of leakage point is controlled at approximately 0.5%,which provides an effective guarantee for quickly determining the fault location in the industrial meter.Figure 48;Table 16;Reference 54...