Mixed H−/H∞ fault detection filter design for the dynamics of high speed train

Here we investigate the fault detection filter design problems of the dynamics of the high speed train (HST). Some of the researches have been addressed the modeling problems of HST [1, 2], but for handling convenience the nonlinear dynamic characters of the couplers are ignored, which is inevitably introducing some uncertainty factors to the dynamic model of HST. The fault diagnosis technology has been gaining great development recent years [3–6], but few researches have been conducted to extend its application to the dynamics of HST. In this article, the nonlinear characters of couplers are considered. And the disturbance attenuation conditions are considered as H∞ norm formulation, while the fault sensitivity conditions are expressed as H− index. We divide the design process of the fault detection filter into three major steps, which are respectively addressed as follows.