Diagnostic Technology Of Metro Traction Converters Based On ARM

With the fast development of urbanization and rail transit, urban rail vehicles, with its advantage of large volume, high speed, energey saving and environmental protection, has become one of the essential tools of modern transportation. As the core part of railway vehicles, traction converter’s real-time voltage and current data reflect the operating status of the vehicle. It will have great significance for all these real-time status monitoring, which needs to build a reliable data processing and transmission platform.In this article designed an ARM-based urban rail vehicles traction converter communication and diagnosis platform under the research background of the national key technologies R&D program for the12th five-year plan "development of key technologies and system for the urban rail transit’s transportation organization, control and security integration".Through the analysis of transmission performance among the existing fieldbus, combined with the data transmission requirements of the power train system, determined the use of Ethernet as a communication transmission scheme. Analyzed traction converter hardware architecture, and compared the deficiencies of original monitoring system based on DSP,PowerPC processor, designd hardware based on the ARM Cortex-A8processor chip AM3359. On this basis, taking full advantage of ARM’s high-performance, low-cost advatages, as well as a wide range of third-party support, exellent network processing capabilities of embedded Linux system, designed a communication and diagnosis platform using ARM-based embedded Linux system as the lower computer, PC with LabVIEW monitoring interface as the upper computer.To achieve the platform a series of work have been done including the creation of a Linux virtual machine, installation of the cross compilation tool chain, transplantation of bootloader, kernel and root file system, based on these, wrote the ethernet driver and application program based on TCP/IP. Using the2ethernets of ARM processor achieved the function of both local and remote monitoring and diagnotics.This article designed the hardware and software of this platform, and gave a solution to realize network communication and fault diagnosis software.