| Abstract:According to the diesel particulate filter(DPF) fault type of blockage and leakage, exhaust resistance test and engine bench test were carried out to get the major fault characteristic parameters including exhaust gas flow, exhaust temperature and exhaust pressure. By comparing with the traditional pressure drop model, an orthogonal least squares method was applied to the DPF fault diagnosis, which allowed to form a DPF fault diagnosis method based on the orthogonal least squares model fitting and to use the collected major fault characteristic parameters to verify the feasibility of the method. By defining an error coefficient vector, the different fault areas formed from different DPF fault types in the generalized failure space were analyzed to provide a theoretical basis for the development of DPF fault diagnosis technology. The degree and type of failure, such as blockage and leakage, can be judged by analyzing the error coefficient vector. On the basis of this feature, the DPF diagnostics strategy can be established. |