“…Mathematical system models for fault detection are a well‐established subject and a lot of survey papers and books have been published, such as Basseville (1988, 2003), Gertler (1988, 1998), Patton et al . (1989, 2000a), Frank (1990, 1996), Patton (1991, 1996, 1998), Basseville and Nikiforov (1993), Isermann (1993, 2005), Isermann and Balle (1997), Chen and Patton (1999), Simani et al . (2002), Blanke et al .…”