one. System Overview
The energy shortage has become a global problem. With the development of the economy, the ever-growing contradiction between the demand for natural gas and the shortage of natural gas has forced the countries of the world to seek effective solutions. Therefore, the use of modern methods to build a real-time monitoring system for natural gas resources, to dynamically grasp the changes and utilization of natural gas resources in the region, and to maximize the use of efficiency is an urgent need to promote sustainable economic and social development.
The remote monitoring system for natural gas resources developed by Shandong Lichuang Integration Co., Ltd. is an automated network management system combining software and hardware. It is through the installation of natural gas resource monitoring devices on natural gas sources or natural gas unit equipment to achieve the collection of natural gas table flow, pressure, temperature and other parameters and the control of natural gas electrovalves. Through GPRS networks, wireless communication and The natural gas resource management center computer communicates and monitors and controls each gas unit in real time. The relevant natural gas table flow, pressure, temperature, and control parameters of the natural gas electromotive valve are automatically stored in the natural gas resource management center computer database. If the gas unit artificially opens and closes the valve and the natural gas or natural gas damage occurs, the management center computer will display the cause of the fault and report it to the police to facilitate the timely dispatch of personnel to the site. The natural gas resource management center may, according to the needs, limit gas production in different seasons and control the opening and closing of valves; for users who are not paying gas resources, the gas resource management center staff can open the valve of the electric valve of the gas unit through the computer system. Remote remote control of degrees to achieve automation, integration of gas resource management/sales and monitoring.
two. System implementation content and design principles
1. System implementation content
1) Realize the real-time data collection of natural gas transmission parameters, and comprehensively grasp the natural gas transmission conditions by collecting the parameters such as pressure, temperature, instantaneous flow rate, and cumulative flow rate of natural gas gas meters, so as to facilitate the timely detection of accident hazards and adjustment of transportation conditions.
2) Realize the functions such as display of acquisition parameters, alarms, production reports, chart printing, data query, fault inquiries, etc., provide data foundation for production monitoring, and achieve the purpose of improving system efficiency and saving energy and reducing consumption.
2. System design principles and basis for design:
GB50093-2002 Specification for Construction and Acceptance of Automatic Instrument Engineering
GBJ131-90 Quality Inspection and Evaluation Standards for Automation Instrumentation Installation Projects
GB50168-92 "Construction and Acceptance Codes for Electrical Installations of Cables"
GB3836.1-83 "General requirements for explosion-proof electrical equipment for explosive atmospheres"
GB3836.2-83 Explosion-proof electrical explosion-proof electrical equipment
GB3836.4-83 "Intrinsically Safe Electrical Circuits and Electrical Equipment for Explosive Atmospheres"
System design principles:
The design of this system plan follows the principle of “advanced technology, simple operation, good scalability, and favorable managementâ€.
2 Advanced technology: The system adopts a more advanced PLC distributed control system structure design. The selected equipment and equipment have superior technical performance, complete functions and reliable operation, ensuring that the entire system maintains an advanced level within a certain period of time.
2 The operation is simple: The system operation has the characteristics of being flexible and convenient, easy to grasp, and the operator can use and maintain conveniently.
2 Good scalability: The design of the system should leave sufficient room for design so that it can be expanded if needed. System expansion requires only the addition of appropriate equipment to avoid unnecessary financial waste.
2 Advantageous management: The system can facilitate the control and management of relevant functional departments in the monitored locations.
three. Project Design and System Architecture
1. The main components of the system:
The entire natural gas monitoring solution adopts a 4-layer network structure, which are:
1. The bottom layer of distributed 485 network bottom device acquisition layer, composed of PLC and related analog quantity acquisition modules, collects the underlying data through the 485 bus.
2. GPRS communication network communication layer, through the GPRS network for data acquisition and transmission.
3. Server Data Acquisition/Processing A data processing center is built through the server and is responsible for data collection, processing, alarming, storage, etc., that is, processing of relevant data will be performed at this layer.
4. Server Group Data Distribution Network/Intranet Information Distribution Network (later extended)
Set up server function groups (group functions are not necessarily required to set up the server) to publish data through the WEB Service interface on the WEB server to implement seamless integration of B/S and C/S systems and publish functions through the Internet web page The group realizes remote WEB access and Win Form access, so that in addition to local workstation control, it is also possible to randomly select WEB workstations and Win Form workstations to remotely control remote locations in any location where Internet access is available.
Acquisition section: The natural gas resource controller developed and produced by the company is used. The natural gas resource controller integrates functions such as reading and storage of gas meter data and function configuration, and reserves function extension interfaces to facilitate the upgrade of control functions in the future.
Communication interface: Natural gas resource controller has two communication interfaces, one of which is RS485 interface, which is used for field debugging or other 485 interface device connection; the other is RS232 interface, which is used for GPRS module interface. Communication baud rate: 9600bps; After the equipment is powered off, the natural gas table data can still be counted to ensure that the data is not lost.
GPRS communication network: The LQ-8200/LQ-8110 GPRS module developed and produced by the company is used to realize transparent transmission between the bottom acquisition equipment and the data acquisition server. You can use TCP/IP or UDP. UDP is recommended for large numbers of applications.
Server group: It mainly consists of data collection server, data server and WEB/WEB SERVICE server. It adopts E-Water SCADA software and mainly includes: 1. GPRS data collection service (Windows service) 2. E-Water data publication website 3. , E-Water Web Service interface; database using SQL 2000 support. In order to achieve data collection and processing and release a series of work.
Workstation: Responsible for system information release and device operation, using natural gas Client WorkStation software, consists of two types of workstations: 1, remote workstations; 2, local workstations; workstation software can be WEB, Win Form can also be used; The remote workstation supports remote remote operation via the Internet; the local workstation accesses the local intranet for operation.
2. Main functions of the system:
(1) Real-time monitoring and display of electronic maps of natural gas sources and user data (flow, pressure, temperature, working status, etc.)
(2) Natural gas source user information management (WR-MIS system)
(3), with real-time, time-sharing, timing; single table, group table of basic data, dynamic pressure, valve opening and other data call measurement / control mode
(4) Sales and sales business management
Contains normal sales management and discounted sales management
(5) Manual call measurement function
The data of the monitoring point can be actively extracted on the workstation at any time.
(6) Data report function
Automatically generate daily, monthly, and annual reports, as well as statistical reports and printing at any time. You can set the automatic print function.
(7), automatic analysis and calculation
According to the monitoring real-time data, the accumulated gas consumption and user consumption (such as hourly usage and daily usage) are analyzed, and an alarm is generated for abnormal conditions; it can be plotted by day, month, and year, and the gas supply trend graph can be calculated. Real-time rendering of monitoring point instantaneous flow curve, pressure curve and so on.
(8) Data storage backup function
The system database can be stored locally, and its storage time is determined according to requirements and computer configuration. The system provides data backup capabilities and can easily manage database data.
(9), fault automatic alarm function
The natural gas resource controller itself has a self-test function. The self-test faults include: gas meter failure, sensor failure, etc. The alarm information can be actively uploaded through the GPRS module; the flow pressure and other collected data are used for alarm judgment in the data acquisition server. Alarm limit alarm, but also according to the parameter value for a variety of state judgments, such as valve opening, short circuit, overload, arrears and a series of alarm information.
(10) System self-diagnosis capability After any problem occurs, the system can perform self-diagnosis function to diagnose faults on any workstation. The fault self-diagnosis can diagnose whether the underlying hardware is normal, whether the communication network is normal, and whether the server group is normal. Such as failure.
(11) System Expansion and Upgrade
The system has an open data interface to facilitate the addition and expansion of later monitoring points.
(12) System security permission setting function
Permissions settings provide comprehensive security authentication, illegal users can not enter the system, legitimate users can perform corresponding operations according to permissions.
3, GPRS system networking GPRS data center can use the application of the line, wireless cat or public network IP form.
Special line method: It is necessary to apply for a special optical cable and a fixed IP address to a mobile company. It is suitable for occasions where the data collection volume is large and the speed requirement is high. At the same time, the cost for applying for a special optical cable is relatively high.
Wireless cat mode: Use wireless cat and GPRS data card to communicate with GPRS module of each collection point. This method does not require a fixed IP address for the computer. The communication speed is moderate and the amount of data is moderate. It is recommended that this system use this method (a GPRS data card with a fixed IP address is required).
Public IP: The computer needs to have a fixed public IP address. Wireless cats and other devices are not used. The cost is low, but the communication speed is slow. Due to the data volume of the public network, the communication may be disconnected.
System operating costs, system operating costs: The system according to the data flow fee. There are currently two types of fee-based charging systems, namely the monthly subscription system and data flow. Please consult your local mobile office for specific charges.