Research Of Localizable Brake Control Unit (BCU) Communication Gateway

The high-speed train's information of control commands,performance monitoring,fault detection and diagnosis is transmitted through its communication network. For the diversified power EMUs,the information of traction and brake control is transmitted through the network to ensure that every unit works in security,at the same time,the state of the motor cars and trailer cars is transmitted to the control car through the network.The brake control commands of CRH2 EMUs are transmitted through the train communication network and the communication medium between terminator and BCU is optical fiber, with HDLC as communication protocol.Since the data imformation of the network protocol is not open,which makes the brake equipments difficult to be replaced,therefore,the analysis of the network protocol is needed to solve the networking problem.This thesis introduces the brake system and communication network of CRH2 EMUs,and in order to solve the localizable BCU networking problem of CRH2 EMUs,a communication gateway is designed based on optical fiber communication technology and SOPC technology.Optical fiber module is designed by HFBR-0400 series;USB module makes data transmit to computer;FPGA module is integrated with BCU IP module,NiosII processor and UART etc.together in Altera FPGA;RS485 mudule achieves communication between gateway and localizable BCU;Power module supplys 5V,3.3V,1.2V to the gateway. The experiment which is based on import test bench verifies the integral function of the communication gateway and Protocol conversion is achieved between terminator(HDLC) and BCU(RS485) with the gateway..