Design And Implementation Of Natural Gas Station Measurement And Control System

With the development of the natural gas industry, the natural gas as a kind of clean and efficient energy is getting more widely used in industry and life. As an important part of natural gas transmission and distribution systems, natural gas gate stations sustain great responsibilities for accurate flow metering and supplying safe and stable natural gas for cities. To ensure natural gas gate stations’safety and efficiency, developing a fully functional monitoring system has important practical significance. On the basis of summarizing the advantages and disadvantages of existing natural gas gate station monitoring systems, this paper designs and implements a natural gas gate station monitoring system with a high degree of automation and information.This paper uses industrial computer, flow computer, PLC, field devices and WinCC to realize the monitoring system. According to the processes and actual demands of gate stations, the paper establishes system’s software and hardware integration solution. The system adopts an upper-lower structure, the lower machine is composed of flow metering unit and PLC control unit, responsible for communication, field data collection and field equipment control. It analyzes flow metering principle and focuses on the design and implementation of I/O distribution, sampling and PID algorithm for valve control. In addition, it designs PLC hardware redundancy solution to improve reliability and completes hardware configuration and PLC program. The upper monitoring system fulfils communication, user interaction, data and system management, remote Web access etc. It communicates with RTU and PLC via Modbus TCP protocol and Industrial Ethernet protocol to collect data and issue control commands. It designs database, archives data periodically, aggregates data to automatically generate data reports and trend graphs. It designs friendly UI, fulfils interactive functions such as valve control, parameters’setting etc. Besides the system real-timely monitors field data, provides alarm and users’operation logging, remote Web access and video monitoring. The paper designs redundancy to improve the system’s reliability. At last the system meets the requirements by functional testing.The system designed in the paper has realized the function of flow metering, process control, data and system management, alarm and operation logging, video monitoring, web access etc. It guarantees safe and efficient operation of natural gas gate stations and provides methods and ideas for developing more comprehensive monitoring systems in industrial fields.