Multiple Faults Diagnosis For CCBâ…¡ Brake Based On Augmented Analytical Redundancy Relations

CCBII is the latest microcomputer-based brake made by Germany KNORR Company, which is widely used in the HXD1and HXD3heavy-haul trains of China. CCBII is responsible for the brake function, due to complex structure and various operation modes, multiple faults sometimes happen simultaneously. In order to ensure the normal work of the brake, it is necessary to develop the multiple faults diagnosis system for CCBII brake. Regarding the CCBII brake as object of study, the system function models of CCBII brake are established, a differential evolution algorithm is introduced to the diagnostic technique, which is based on the augmented analytical redundancy relations to implement multiple faults detection and location.Firstly, the control relationship among working modules and the comprehensive function among air channel structure are analyzed on the basis of the basic characteristics and system components of CCBII brake. Through the analysis of fault classification and fault features, a multiple faults diagnosis scheme based on the augmented analytical redundancy relations is proposed. In the light of the complex structure and various components with strong coupling, we take advantages of power bond graph to obtain a mathematics model of brake system. The basic principle and modeling process of power bond graph method is introduced in detail. According to three brake functions of CCBII brake, we use power bond graph method to model them respectively.Secondly, based on models of the three brake functions, the augmented global analytical redundancy relations (AGARRs) for the system are derived. Then the mode-change signature matrix and fault signature matrix are obtained. Mode tracking is realized by comparing these two signature matrixes with the coherence vector. Once the mode tracking fails, the candidate fault assumption set is established correspondingly. Furthermore, fault parameter estimators are designed based on differential evolution algorithm. The multiple faults are identified among the hypothesis set by calculating the value of mean fitness function. The real-time online faults detection of CCBII brake system is realized, and we use the Matlab simulation tool to verify the effectiveness of the proposed methods.Finally, the proposed multiple faults diagnosis system has already been tested in the CCBII brake system of high power maintenance base in Wuhan Railway Administration. We propose the overall design framework and introduce the gas circuit design, hardware design and software design. Practical application proves that the diagnosis system can detect the multiple faults quickly and accurately.