Design Of A Smart Home System Based On Smart Sockets

Smart home system can improve people's safety,convenience and comfort.Although the smart home system had nearly three decades of development history,there are still some problems:no uniform standards resulting poor scalability of the system;no energy-saving measures or single energy-saving measures.To solve the above problems,a smart home system based on smart sockets was designed.There are two highlights,one is that a home network plug and play protocol was explored,which can be standardized,and the other is that a smart socket was designed,which can be remotely controled.Additionally the statistic of power consumption of electrical appliance and the elimination of standby power of electrical appliance were realized based on the recognition.The system focused on the design of home network plug and play protocol(HPnP),home gateway,smart sockets and smart devices.Home network plug and play protocol was the foundation of communication between the home gateway and the other modules.The protocol can be promoted used as a standard,which referenced the protocol and timing requirements in USB device enumeration phase and combined with the UPnP protocol description for devices.Ultimately the smart devices could access to system with zero configuration.Home gateway was to manage and organize the smart devices in the family,including network management,device management and user-interface management.Network management was mainly to provide network services for a variety of applications,and process communication packets according to HPnP protocol.Device management was mainly to process devices' registration,status updating,exiting and timeout.User-interface management was to automatically generate devices'user-interface based on data-driven methodology.Smart sockets were the basic unit to build the smart home system.Firstly,the active power and power factor were extracted as eigenvalues of the measured electrical appliance through the finite state machine.The type of measured electrical appliance was then found from the sample library using the Euclidean distance.The problem of electrical appliance diversity was solved by introducing a learning function.The old samples were removed using the memory principle.In order to facilitate smart sockets' upgrade and maintenance,one kind of remote upgrade technology was achieved based on Web.Smart devices implemented some specific functions in the system,including centralized control of lighting equipment,data acquisition equipment and infrared control equipment with learning function.Some key technologies achieving these smart devices included data frame determination,software timer,level conversion and circuit isolation.The test results show that,the home gateway without changes can be connected by different types of smart device,indicating that the function of plug and play was achieved.The similarity among the same type of electrical appliances is more than 80%,and it can recognize most types of electrical appliances.Finally,the statistic of power consumption of electrical appliance and the elimination of standby power of electrical appliance were realized.An energy-saving measure was introduced in the smart home system.