Research And Implement Of Wireless Sensor Network Based Buildings Energy Consumption Monitoring Systems

With the rapid development of Chinese economy, the issues about energy consumption in buildings have become increasingly prominent, which needs energy-saving projects exigently. Wireless technology is an important technical supports to develop green energy-saving projects and build green energy-saving buildings. Wireless sensor network that is further extension of wireless technology and Internet is deemed to provide more effective technical supports for energy saving. Therefore, there are great practical significances to research the wireless sensor networks based building energy consumption monitoring and analyzing application.On the issues of high-cost and lack of scalability, flexibility in traditional systems for energy consumption monitoring in buildings, the paper designs hardware and software architectures; develops wireless sensor nodes; transplants the communication protocol stack for sensor nodes; finally, develops the building energy monitoring system by wireless sensing technology and software engineering methods. Testing results show that the system meets the application requirements well from the aspects of data collection, on-line monitoring, information storage and management. The major contributions are as follows:1. Based on the study of related work about buildings energy consumption supervision and wireless sensor network applications, three-tiers structured hardware and software architecture is proposed for wireless sensor network system for building energy consumption monitoring aimed at the problems of traditional energy monitoring systems.2. According to the particular requirements of energy measurements in building surrounding, the paper develops wireless sensor nodes by wireless sensing and communication technologies, on which Atmage128L is adopted as the microcontroller, CC2420 is adopted as the radio frequency chip for data transmission, TSL2550 and SHT11 sensors are used for temperature, humidity, light measurements in building surrounding. Testing results show that the sensor nodes basically meets the requirements of data collection with good measurement accuracy and short response time.3. For the energy monitoring requirements, building energy monitoring software system is developed on open source integration platform (Qt) by software engineering and graphical visualization methods, which enables real-time three-dimensional and two-dimensional curve display, historical curve displays, as well as the exceptional sound and light alarm. The result shows that the system achieves real-time monitoring, information storage and management, and preliminary data statistics.4. On the communication differences between wireless sensor network and the Internet differences, serial and TCP/IP based data transferring functions are implemented on the coordinator sensor nodes by network and communication technologies, which preliminarily achieves the connection and communication between wireless sensor network and Internet.5. On the issues of limited storage resources and lack of shared protocol stacks for sensor nodes, a simple protocol stack for wireless sensor network is proposed by functional cutting and transplantation on Zigbee protocol stack. The hardware device drivers, device control and data management are implemented in physical layer(PHY). MAC frame format definitions, MAC frame detections, as well as MAC frame package and analysis are implemented in MAC layer(MAC). Logical address assignment, network forming, neighboring table definition and maintenance, routing and data forwarding functions are implemented in network layer(NWK). The device object and its management are cut in application layer, otherwise, sockets based network communications function are developed in application layer(APL). The results show that the protocol stack basically achieves networking, tree routing and message forwarding.