GPRS street lamp monitoring system scheme
I. Overview
With the development of the times, the pace of urban modernization is accelerating, and the demand for urban road lighting and urban lighting projects is also greater, and the contradiction between energy supply and demand is becoming more and more prominent. The requirements for energy saving, energy saving and green lighting are more and more urgent. ,Higher and higher. It is no longer sufficient to adopt the traditional methods of manually controlling and clocking urban lighting systems. How to make full use of high-tech means to resolve these contradictions has become a new and critical issue in the current lighting control field. Urban road lighting automation control and intelligent management are one of the symbols of urban modernization. The economic and social benefits it brings are very significant. Its promotion and implementation will also be an important part of municipal engineering construction.
The automatic lighting monitoring and management system can flexibly switch on/off the light, understand the operating parameters at any time, find faults in a timely manner, and change the traditional manual “tour light†system to the “on duty†system, which greatly improves the efficiency of lighting system management. The system can automatically store the collected data and statistics, and can query and print at any time, greatly improving the management level. At the same time, it can also reduce energy consumption and increase equipment through night-night lights, midnight lamps, and intelligent pressure adjustment. Lifetime, get good economic benefits.
Second, GPRS transmission scheme advantages
China Mobile GPRS system can provide wide area wireless IP connection. The oil well data acquisition and transmission system is built on the mobile communication company's GPRS service platform to realize the wireless remote monitoring and control of street lamps with the advantages of making full use of the existing network, shortening the construction period, and reducing the construction cost. Moreover, the equipment is easy to install and maintain. After a comparative analysis, we chose China Mobile's GPRS system as a data communication platform for environmental information collection and transmission systems.
GPRS street lamp monitoring system has the following characteristics:
1, high stability:
Compared with SMS SMS, GPRS DTU adopts connection-oriented TCP protocol to avoid packet loss and ensure reliable data transmission. The center can perform data transmission simultaneously with multiple monitoring points without disturbing each other. The GPRS network itself has a perfect frequency division multiplexing mechanism, and has a strong anti-interference performance, completely avoiding the "collision" phenomenon of multi-frequency band of traditional digital radio stations.
2, real-time strong:
GPRS has the characteristics of real-time online, small data transmission delay, and supports simultaneous transmission of multiple points. Therefore, the monitoring center can perform two-way communication between multiple monitoring points in real time to meet the system's real-time data collection and transmission. The request. At present, the actual data transmission rate of GPRS is about 30 Kbps, which fully meets the requirements of system data transmission rate (≥10 Kbps).
3, widely used:
The GPRS network has achieved nation-wide coverage, and there is no limit to capacity expansion. There is no limit to the access location, and it can meet the monitoring needs of city lights.
4, low-cost construction:
Due to the adoption of the GPRS public network platform, there is no need to build a network, simply install the equipment, and the construction cost is low; network maintenance costs are also eliminated.
5, low operating costs:
Using GPRS public network communication, all countries are charged at a flat rate, eliminating the need for expensive roaming charges. The GPRS network can be based on actual data traffic accounting data (1 minute - 3 minutes/1 kilobyte), or it can be There is no limit on monthly charges for monthly subscriptions, which enables low-cost communications for the system.
6, centralized control:
Through the GPRS data monitoring center, remote control of street lights can be realized, such as remote switch control and remote status query.
7, the system's transmission capacity, expansion capacity is good:
The street lamp monitoring center must connect with each street lamp monitor in real time. Due to the large number of street light monitors, the system is required to meet the needs of sudden data transmission, and GPRS technology can well meet the needs of transmitting bursty data; since the system adopts a mature TCP/IP communication architecture, it has a good expansion. Performance, a monitoring center can easily support communication access for thousands of street light monitors.
Third, solution introduction
Since GPRS communication is a data packet communication network based on an IP address, the monitoring center computer needs a fixed IP address or a fixed domain name. Each data collection point uses a GPRS module to access the host through an IP address or a domain name, thereby performing data communication.
(I) System Structure
1ã€Street light control point:
The street lamp monitor is connected to the GPRS DTU terminal through RS232 or RS485 interface. The control command of the monitoring center is transmitted to the street lamp monitor through the GPRS DTU terminal to realize remote control. The information collected by the street lamp monitor is sent to the GPRS wireless network through the GPRS DTU. .
2, control center station:
a) Public network access plan
The server uses the public network to access the Internet, such as ADSL dial-up/telecommunications broadband Internet access, etc., to apply for a fixed IP address on the public network; data collection applications with small and medium capacity can be realized.
b) Private network access plan
The server adopts the DDN dedicated line provided by the provincial mobile communications company and applies for the configuration of a fixed IP address, which is connected to the GPRS network. Because the DDN dedicated line can provide higher bandwidth, when the number of monitoring points increases, the center can meet the demand without capacity expansion, and large-capacity data acquisition applications can be realized.
After receiving the data from the GPRS network, the RADIUS server of the monitoring center first performs AAA authentication, and then transmits it to the host computer of the monitoring center. The data is restored and displayed by the system software, and data processing is performed. This further enhances the data communication security performance of the system.
3, GPRS/GSM mobile data transmission network:
The data of the street lamp monitor is decoded and processed by the air interface function module of GPRS/GSM network at the same time, converted into the format of data transmission in the public network, transmitted through China Mobile's GPRS wireless data network, and finally transmitted to the IP address of the monitoring center.
(two) system plan
Each spotlight monitoring point uses Monternet’s MRM6155 DTU transparent data transmission terminal and is connected to the monitoring center through a mobile GPRS network. Each monitoring point uses the GPRS general data card or APN special data card of the mobile communication company. At the same time, the monitoring center registers the GPRS terminal number of each point and associates it with the information of the street lamp point for identification and maintenance processing. Street light control center running monitoring software to achieve street light information monitoring.
All authorized monitoring points can use this system:
1. The monitoring point must use the mobile unified APN card. Users can only use this card to communicate with the street lamp monitoring center.
2. Terminal equipment uses GPRS mobile data communication terminal provided by Monternet Technology.
3, the user registration: in line with the provisions of the municipal management department.
(III) Product Features
The system uses MRM6155 DTU wireless transparent data transmission terminal. The product is based on China Mobile's GPRS network and features high performance, high reliability and strong anti-interference ability. It provides a standard RS232/RS485 interface. It can be directly connected to PC, SCM system, RTU monitoring and control terminal, PLC, GPS receiver and data concentrator. Such connections, with remote diagnostics, testing, and supervision functions, to meet the data acquisition and control between various industry dispatch or control centers and many remote sites.
Highly integrated GPRS and TCP/IP technologies that enable point-to-point, point-to-multipoint and other flexible wireless networking
Built-in embedded CPU to complete complex network protocols, support PPP, ICMP, TCP, UDP, DNS and other protocols to provide transparent transmission channels for user data
? Stable performance, long-term reliable operation under harsh environment, built-in watchdog circuit
? support always online mode, the user can set the heartbeat interval and heartbeat packets, keep the device long-term online
• In the event of a network failure or a central shutdown, the DTU has automatic reconnect after condition recovery
DTU can work in full transparent transmission mode to ensure no loss of 100%, unless the network fails
DTU can work in full transparent transmission mode and user command mode to give DTU the dual role of fool and flexibility
Support Center is fixed IP or dynamic IP + dynamic domain name resolution
Provide RS232/RS485/RS422 communication interface, baud rate selectable, from 300bps to 115200bps, start/stop bits/parity check optional, RTS/CTS flow control optional
Supports near-end and remote parameter configuration and access
Remote wake-up support
Built-in FLASH memory can save user configuration parameters for a long time
? support serial port upgrade firmware program
? Support APN data private network business
Anti-interference design, suitable for harsh electromagnetic environment applications
(four) safety measures
This system requires extremely high system security and stability. Security protection is mainly to prevent intentional and unintentional damage from inside and outside the system. Network security protection measures include channel encryption, source encryption, login protection, access protection, access protection, and firewall. Stability means that the system can operate continuously for 7×24 hours. Even if there are hardware and software failures, the system cannot be interrupted.
The data center can be accessed through the public network, or can be accessed by a mobile private network. The cost of adopting the public network access method is relatively low. Enterprises do not need to lease the leased line. When using the data line access, the GPRS data transmission equipment must be authenticated by the Radius server. The entire data transmission process has been protected by encryption, and the security is relatively high, which can fully guarantee the speed and quality of network services.
1. APN data private network mode: The APN server is configured in the internal network of the enterprise, and the APN data private network is used for the mobile terminal. Because the data private network is used, the server is isolated from the public network Internet, and illegal invasion can be effectively avoided.
2. Using the uniqueness of the SIM card to authenticate and authorize the user's SIM card mobile phone number, bind the SIM card number and the APN at the network side, demarcate the range of users that can access a certain system, only the SIM card mobile phones belonging to the specified industry No. can access the dedicated APN. The mobile terminal and the data center use the special APN assigned by China Mobile to access the wireless network. The SIM card number of the ordinary mobile phone cannot call the dedicated APN.
3. The DTU ID number and password can be separately configured for each GPRS data transmission device. Application layer authentication is performed when the data center logs in. Other GPRS devices that do not have the DTU ID number and password assigned by the data center cannot log into the system. The security of the system is further enhanced.
4, data encryption: The entire data transmission process can be encrypted protection.
5, network access security authentication mechanism: the use of firewall software, set up network authentication and security features to protect system security.
Fourth, the benefits of using the system:
1, increase the lighting rate
After the system is put into operation, problems found in the operation of the street light can be found at any time, which can be dealt with at any time to increase the lighting rate.
2. Save energy and reduce electricity expenses
After the system is put into use, it is possible to carry out the lighting mode of “one light and one light†or “two light and one light†in the case of rare pedestrians and reduced traffic in the late night. This will not only bring the owner of the pedestrians at night to sleep, but also save a lot of energy. Electricity expenses. After the single control is implemented, the control of the lights of the partitions is usually implemented by laying two-wire cables. At present, at least 50% of the cable cost and construction cost can be saved. This is very convenient for retrofitting of existing systems without laying extra cables.
3, extend lamp life
After the energy-saving operation of the street lamp intelligent control terminal intelligent voltage regulation mode, the voltage of each lamp can be kept relatively stable, especially when the voltage is increased in the latter half of the night. According to the test, under the normal voltage (220V), the sodium lamp voltage is 100V, after the voltage is increased (230V-240V), the sodium lamp voltage can be increased to 120V-150V; the normal voltage environment is reduced and the sodium lamp voltage is generally 85V after energy-saving operation. The voltage of the sodium lamp can be maintained at about 100V under a voltage rising environment. From the theoretical and practical use environment, the use of voltage regulation and control of energy saving can extend the service life of street lamps. Therefore, the voltage adjustment method has the effect of double energy saving.
4, save manpower, material resources, improve management
Due to the real-time monitoring of the working status of each street lamp, each road section, and lighting engineering point, the computer can collect the faults in time and write them into the database for maintenance the next day; use the dynamic real-time analog display screen to monitor the street lights of the city and the attendants. In the central control room, the on-site operation of the streetlights can be overviewed, thereby reducing the maintenance cost of the patrol lights and reducing the work intensity of the patrolling personnel, thereby greatly improving work efficiency. In addition, in bad weather, according to the data collected by each street light control intelligent terminal, it is analyzed and corresponding emergency measures are taken to avoid the occurrence of major traffic accidents.