Research And Design Of Communication Protocol Converter In Power Station Monitoring System

With the improvement of the electric power automation, it requires a higher level forthe power station monitoring system. All kinds of monitoring data must be transmittedsafely and reliably in order to make the power station monitoring system “non-attended(few-on-duty)”. So it will make the interface between host machine and field control unit aswell as the software programming more complex. The implementation of a communicationprotocol converter which is highly integrated with multi-serial and multi-protocol ispresented in this topic. The latest STM32F407micro-controller from the ST company wasadopted as the key control unit of the communication protocol converter. The overall designscheme of both hardware and software also are put forward in this article, and thecommunication protocol converter device was completed according to the previous designplan.The hardware circuit design mainly includes: main controller module and peripheralcircuit, communication interface module and data storaging module. Among them, the oneof RS-485, CAN, USB and Ethernet and six RS-485communication interfaces are designedin this system design. And SPI and IIC bus interface circuit is designed in the data storagingmodule.The software part is programmed in the structured and hierarchical design concept,which mainly includes the system main program, data processing module and protocolsconversion module. Among them, the data processing module puts the input data into thestack at first, the head of the stack is sent when it needed to make the data real-time.Protocols conversion module is the core of this design, which changes the data into thesame format, then converts them to the right communication protocols associated with thedestination address. This device has realized the conversion between RS-485and CANbus, supporting a variety of communication protocols, such as MODBUS RTU, DT/L645,CDT communication protocol, etc.Finally, the experimental board was debugged and tested many times. And theexperimental results show that in terms of safety, accuracy and real-time performance, thesystem is highly reliable, safety and feasible.