Study And Design Of Monitoring System For Metro Vehicle Converter Based On PowerPC

With the development of rail transportation, the subway has become an effective method to ease urban traffic congestion. It’s essential to ensure safe and stable operation of the metro vehicles. Converter as the core part of the vehicle, real-time monitoring of vehicles converter operating status is particularly important, and monitoring system’s large amount of data transmission needs for more effective communication technology as a support. This article rely on the National Key Technologies R&D Program for the11th Five-year Plan-"Energy Feedback Traction power supply and Traction drive system", for the Guangzhou Metro Line No.1vehicle converter, launched a new monitoring system based on PowerPC.Considering metro vehicle converter and monitor system requirements, this article analyzed the deficiencies of original monitoring system based on DSP processor, designed a monitoring system hardware platform based on the PowerPC processor MPC5125as the core, and builded embedded Linux operating system. Let PowerPC fully exerted its high frequency, low power, high-performance advantages, and embedded Linux system’s powerful network processing capability, to enhance the overall performance of the monitoring system.Firstly, this article builded a development environment through the transplantation of U-Boot, the Linux kernel and root file system. Secondly, according to the embedded systems character device driver structure, this article designed PowerPC drivers and applications for SPI serial communication, achieved data transfer between PowerPC and the main control unit based on the SPI serial interface. Thirdly, using Ethernet UDP User datagram Protocol, designed Ethernet communication program to complete transporting the monitor data to the upper Lab VIEW interface, including vehicle running state, the converter voltage and current values, and PowerPC could receive control instructions issued by the interface at the same time, achieved vehicle converter human-computer interaction based on Ethernet, and proposed a solution for UDP unreliable connection problem, Fourthly, PowerPC would be triggered through the GPIO external interrupt, and immediately upload the fault signal to the monitor interface, and stored the fault data into Flash, added fault handling capacity for the system. Finally, this article used the multi-tasking process control method through Semapore on the Linux operating system, making the PowerPC processor running at maximize efficiency, improved system throughput capacity. After all design, through the joint experiments with the upper level control interface LabVIEW and the main control unit, the monitoring system could reach the expected demands.