Design And Implementation Of Remote Management System For HD-PLC Device

In recent years,the development of “Safe City” security market and the increase of requirements to upgrade video surveillance devices from analog pattern to digital pattern have stimulated the market demand for EOC(Ethernet Over Cable)products.Modulate the Ethernet signal and transmit it on analog cable,and then the data signal can be demodulated and separated from original signal in user terminal.Application of EOC technology above can achieve high speed network signal transmission without increasing the wiring and changing the original cables.Power line communication technology(PLC)is the core of EOC products.At present,HD-PLC(High Speed Power Line Communication Technology)is the general power line carrier communication tech in the world.It is created and developed by Panasonic in Japan.After decades of technology accumulating,it has a high modulation efficiency and stability.However,the problem detection,configuration and management for modulation chip is at a very primitive stage.If you want to change the factory settings of hardware parameters,you must at first connect to device through serial port of network interface,then manual input commands in PC in order to achieve what you want.It is not only tedious,but can not anticipate problems and easy to suffer heavily loss.This paper focuses on the design and implementation of remote management system for EOC equipment based on HD-PLC technology.At the beginning of the article,this paper describes the application object of the management system,namely the EOC-PLC device,and briefly describes the applying status of the relevant technology in the domestic and international.Then introduces the overall structure and functions of management system,including information acquisition,commands forwarding,data reporting on Master device,device discovery,remote control of LAN management tool and cloud data collecting,commands issuing,parameters displaying of cloud server.Also analyze its working principles.Formulate three-party communication protocol with the reference of External Command Protocol provided by Panasonic.Repackage external command data into self-make protocol interface,in order to establish a complete and secure communication infrastructure.When implementing this system,choose STM32 F series MCU,combined with the ucos2 operation system,to build local agent on Master device,which is made up of information collection procedure,monitoring procedure,reporting module and forwarding module.Select LWIP as the basic network protocol stack to achieve network communicating function.The Agent uses UDP protocol to exchange data with PLC device,intranet configuration tool while using registered MQTT service to communicate with cloud server.And in view of the description for cloud equipment information displaying and commands issuing has to be made referring to the work of front-end engineers,therefore this article does not delve into that part,only focus on its communication protocol and system framework design.Use C# object-oriented programming language,combined with the Visual Studio integrated development environment,to design the UI and do the function development of intranet management platform.After the completion of works for local agent,LAN management platform and cloud server,real-time remote control and configuration for PLC equipment can be easily executed via management tool.Moreover,with the information auto-reported from local agent to cloud server,many potential problems can be predicted to avoid heavily loss and maintain normal workflow.