Research On The Communication Technology Of Hydrological Automatic Flow Measurement Platform

As the main realization method of river data collection in China at present,the hydrological automatic flow measurement platform has made great contributions to the hydrological industry.The automatic flow measurement platform developed by this team takes PLC as the core and equipped with different flow measurement equipment,establishes communication with the general control center through the digital transmitter-receiver,and the instruction issuance and data collection and return are all completed by the digital transmitter-receiver.However,the current measurement platform communication method is relatively simple,and the current communication is occasionally interrupted in the complex external environment.In addition,the platform needs to provide different interfaces for the different device carried.There is no unified universal interfaces,which is more complicated to use.In response to the above problems,this subject combines the analysis of the communication of the current flow measurement platform,based on the current access of existing equipment and a comprehensive analysis of various communication methods.It is planned to join the wireless communication technology based on the bridge as an emergency communication solution.Through the programming of the platform PLC Modbus-TCP protocol loading program,the flow measurement software program and related instructions,the analysis of the effectiveness of the two communication methods,the switching of the communication method and the writing of the emergency program in emergency,the wireless bridge communication method is added.It comes from the system and is used as an alternative to the communication of digital transmitter-receiver to supplement the failure of the communication interferences of digital transmitter-receiver.On this basis,the client and PLC communication connection based on the OPC server are developed,the appropriate OPC server is selected,the client communication program based on the OPC interface is written,and the platform PLC data and its auxiliary flow measuring equipment are connected to the OPC server.Collect data from each device centrally and provide standard interfaces for other client software to access.The addition of the wireless bridge communication of the flow measurement platform supplements the communication failure in the rare cases of the flow measurement platform operation project,which improves the safety of the flow measurement platform.Wireless communication based on the interface of OPC provides an interface for external flow measurement device and external software,breaking the sealing between each device and measuring station,and improve the compatibility and universality of the platform.