The intelligent street lamp control system is composed of dispatching center, street lamp monitoring center, communication platform, street lamp remote measurement and control terminal, metering and measurement (AC voltage transformer, AC current transformer, etc.) equipment and control equipment (AC contactor, etc.). The following editors will introduce the development status of the intelligent street lamp control system.
1. System function requirements mining
As a new product in the field of control, the functional requirements of the street lamp control system are still being tapped. At present, it is mainly focused on energy saving and convenient management.
Street lamp control: remote, on and off and dimming control of street lamps by means of whole, group or single lamp;
Scenario control: You can set the street lamp working scenario and control strategy to achieve unattended work;
Data collection: Collect and upload the working status, alarm, working voltage, current, accumulated power, etc. of each street lamp to the server;
Street lamp management: statistical analysis of street lamp feedback data to generate maintenance alarms and data reports, the alarm content can be timely notified to relevant maintenance personnel;
Geographic Information System (GIS): Use commercial or free geographic information systems to achieve real-time positioning of street lights and other related equipment to improve operability.
In addition, after contacting a large number of customers, some customers' requirements are as follows:
Distribution box control: At present, some provinces and cities have adopted the "three remote" control of the distribution box, which has played a demonstration role. Some customers have requested to add the remote control of power distribution box power and the monitoring of power parameters in the street light control system, or integrate the existing distribution box control system into the street light system;
Cable theft and electricity theft alarm: The situation of cable theft and electricity theft in some areas is very serious. Customers suggest that you can add cable theft and electricity theft alarm functions;
Illumination detection and control: detection of ambient light brightness and automatic dimming;
Activity detection: Recognize whether there is human activity through human infrared sensing, image pattern recognition, etc., and adjust the brightness by region;
Extended camera function: used to monitor the running status of street lamps and the presence or absence of damage.
In the future, the functional requirements that may generate and guide users to use mainly come from network scale and technology integration, such as:
Expansion of functional areas: Due to the large number and wide distribution of terminal nodes of the lighting control system, once the scale is formed, it can be used for urban environment monitoring, traffic management, public security, etc .;
Visible light communication: Using the rapid response characteristics of LED light sources, visible light communication can be carried out. At present, many research institutions and universities have begun to study this and have some applications in some fields. If this technology is used in street light control There will undoubtedly be more applications on the system and street lights;
Sensor application: The development of sensor technology will bring more room for expansion to the function of the lighting control system.
2. Common architecture of street lamp control system
The street lamp control system continues the architecture of the Internet of Things and is composed of an application layer, a network layer, and a perception layer.
Among them, the application layer is composed of a series of software. At present, most companies use B / S architecture, and some companies use C / S architecture and configuration software. Generally includes:
Data collection and control components: used to connect network layer devices, obtain data or send control commands;
Configuration components: used to initialize the system platform and database, import the device list, etc .;
Management component: Users can operate and view street lights and other devices through this component, and perform functions such as generating lists and alarms.
The network layer is called a concentrator in the street lamp control system. It generally uses an ARM kernel and Linux or VxWorks and other operating systems to implement routing and some simple control and data collection functions.
The perception layer is mainly composed of a large number of lighting controllers, which are used to perform functions such as dimming / switching of lamps and collecting lamp data. If necessary, other sensors or actuators can also be expanded, such as illuminance meters, human body infrared sensors, vibrators, etc.
3. Street lamp control system equipment and design requirements
In the street light control system, some devices need to be redefined and developed, such as concentrators and lighting controllers.
The basic functional requirements of the concentrator are as follows:
First, the upstream data interface generally uses a GPRS router or GPRS transparent transmission module, and is also equipped with a network port, which can be connected to an Ethernet or optical transceiver, and uses TCP / IP to communicate with the application layer software; second, the downstream data interface is based on the actual needs of the manufacturer , Can be connected to ZigBee wireless communication, power carrier, RS485 and other communication modules to communicate with the sensing layer equipment; third, RS485 communication interface, user expansion function modules, such as electricity meters, illuminance sensors, etc .; fourth, digital and module I / O several, used to control the contactor or use the phase line circuit voltage, etc .; Fifth, the polling function, can periodically poll the managed sensing layer equipment, and upload the polling results to the server; sixth, can be offline Operation, when the server network fails or does not exist, you can use the local control strategy to control the sensing layer device.
The basic functional requirements of the lighting controller are as follows:
First, the data interface can be ZigBee wireless communication, power carrier, or RS485 communication; second, it has one or more switching functions for switching back-level equipment (such as lamps); third, it has one or more dimming Interfaces, such as PWM, 0-10V or 4-20mA current output, etc., are used for the dimming function of the rear stage lamps; fourth, it can collect working parameters such as working current, voltage, accumulated power, and upload data according to the requirements of the concentrator; Fifth, there are alarm functions such as over-voltage, over-current and over-temperature;
In addition, both the concentrator and the lighting controller are used outdoors. In addition to the protection performance parameters such as waterproof and dustproof, the setting of related parameters such as high temperature, aging of the casing, lightning protection, and static electricity must also be considered. The use environment must adapt to the power environment of the street lamp system, and also meet the national mandatory standards for electronic products.
4. Street lamp engineering construction and system database initialization
Compared with the traditional street lamp system, each (or several) street lamps will be equipped with a lighting controller, and according to the network scale, several concentrators need to be installed. The wireless controller is generally installed inside the lamp due to the installation location's influence on the signal strength; while the power carrier or RS485 etc. are not very demanding on the location, they can be installed in the maintenance window of the light pole. Generally, the wireless concentrator is installed on the electric pole or street lamp, while other concentrators can be installed on the street lamp control system.
Early evaluation of the use environment: such as whether the voltage is stable and whether the harmonics meet the requirements; for the power carrier, it is also necessary to detect whether the interference is near the carrier frequency, and the wireless communication needs to check the situation of on-site co-frequency wireless interference and the status of obstacles;
Network planning: plan the installation location of the concentrator according to the node distribution, network status, power distribution, etc .;
Equipment installation: lighting controller and concentrator installation, control room design, etc .;
Equipment detection and networking: Check whether the equipment is installed correctly, and record the network acceptance and maintenance; check whether the wiring and installation of the concentrator and lighting controller meet the specifications, and regularly check the node connectivity rate.
In the networking process, the workload of obtaining a large amount of street lamp node information and entering it into the server database is very large. The existing system is basically completed manually or semi-automatically.