Fault Diagnosis Technology Research And System Design For SAB Type Train Anti-skid Electronic Components

SWKAS20C train anti-skid braking system which has a high market share is applied to the domestic train travelling at a speed of 160 km/h.Due to mechanical vibration,environmental corrosion,device aging and other reasons,train anti-skid device may inevitably produce fault.In order to check the fault condition and improve the efficiency of fault detection and maintenance for the host of train anti-skid device,the expert system of fault detection and localization in component level is designed for the SAB WABCO company's SWKAS20 C type train anti-skid device.Firstly,the anti-skid device is divided into a plurality of functional modules by studying its working principle.According to the main circuit schematic for each functional module with maintenance experience,analyzing the fault-prone location and fault causes,and laying the foundation for the design of follow fault diagnosis system.Secondly,a multi-fault classifier based on support vector machine is designed by studying the fault diagnosis technology of analog electronic circuit,which is used to train and test the fault sample data of the host's analog circuit.The modified algorithm helps to optimize the parameters of vector machine,which improves the accuracy of the fault diagnosis.The diagnosis experiment of the actual circuit shows that the support vector machine method of the analog circuit can effectively diagnose the fault.Thirdly,an independent fault diagnosis system is designed for the anti-skid speed sensor,which includes hardware and software parts.The faulty speed sensor can be identified by recording and testing its performance indicators.The fault diagnosis system is applied to the detection of multiple target speed sensors,and the experimental results show that it has high reliability and strong function to meet the requirements of diagnosis.Finally,a test platform is built to simulate the operating environment of the train and simulate the host in a variety of state failure mode.The fault diagnosis expert system of MFC host circuit board is designed by using the VS2010.Applying the expert system to the faulted host,the result shows that the expert system can extract the fault accurately,locate the fault and give the expert solution.