Study On Application Of ZigBee Technology In Indoor Lighting Control System

As a subsystem in the building system, lighting control system is becoming more and moreclosely in touch with people’s daily life, it not only directly affects the comfort of people’s livingenvironment, but also consumes large amounts of electric energy. In today’s increasingly seriousenergy problem, how to reduce the energy consumption, improve the comfort of the livingenvironment and realize intelligent control of interior lighting system increasingly become the focusof attention. ZigBee technology is the latest and the most promising technology in the wirelesscommunications technology. Compared with other wireless technologies, transmission distance ofthe ZigBee technology is far, and it can build a large network, the price and overall powerconsumption is relatively low. As it is precisely these advantages into consideration, the ZigBeetechnology for indoor lighting control system can solve the high cost, high energy consumption,management and maintenance difficulties, poor flexibility, and no expansibility and other issues inthe traditional indoor lighting control system.By analyzing the background and significance of the indoor lighting control system andcomparing the development of the lighting control system at home and abroad, this paper expoundsthe ZigBee technology advantages in the indoor lighting control system. This paper also presentsthe general scheme of the system and proposes the lighting control system in which GPRS wirelessnetwork technology combines with the ZigBee technology. The whole structure of the system isdivided into five parts: a client interface, a server, a centralized controller, lights nodes, and ahandheld remote control. The basic principle of the system is as follows. The PC client softwareconnects to the specified server by setting the IP address and port number of the network; GPRSwireless modules are controlled by STM32microcontroller, and STM32microcontroller commandGPRS modules to make GPRS modules and the PC client software share a server through all sortsof configuration of the AT; The STM32MCU will receive GPRS messages through the serial portforwarding via ZigBee coordinators, when ZigBee terminal lights nodes on the same networkreceive commands from the coordinators, and execute the corresponding commands control andreturn state, the corresponding messages of the terminal nodes can be forwarded to the GPRSmodules via the coordinators by the STM32; The handheld remote control will forward key valuesto control the corresponding terminal lights nodes via the ZigBee coordinators.The hardware and software design of ZigBee is the core of this paper, through the ZigBeeself-organizing wireless networks, it can be achieved each lamp monitoring on the building, as wellas a variety of data collection. The ZigBee is designed primarily to achieve the establishment of the network, make the serial communication with the STM32, detect the current and light intensity on asingle lamp node, and realize relay switch control and PWM dimming control. In this design, thereare three types of ZigBee nodes. The first ones are ZigBee nodes (or coordinators) on the controller,which are the core of the ZigBee network and are responsible for the establishment, maintenance ofthe network and the forwarding of messages; The second ones are ZigBee nodes with the functionof routing, whose main function is to accomplish the transmission of messages and realize thedetection and control of a single lamp; The last ones are terminal ZigBee nodes, which can onlyrealize the detection and control of a single lamp without a router messaging capabilities. The paperintroduces the hardware design and implementation of procedures for each type of node in detail.In the experiment of the system, the data are compared and analyzed from some aspects, suchas the communication distance, the packet loss rate in the receiving process, the current sampling,and PWM wave control. The measured results show that the design is more intelligent, morescalable, easier to maintain, and can solve the problems such as wasting energy, compared with thetraditional indoor lighting control system.