Unknown input nonlinear observer for component fault detection and isolation of dynamic systems

Fast Fourier transform and wavelet‐based statistical computation during fault in snubber circuit connected with robotic brushless direct current motor

“…But as per Wang et al [16], the results obtained from these fault detection techniques are influenced by model uncertainties, system faults. Due to the unpredictable and unknown uncertainties, these cannot be mathematically modelled, which further resulted in the differences between the results obtained from the simulation and performance of the actual system and provides wrong results in the fault detection technique based on the model [17]. In 2000, Liu et al showed the parameter estimation and the neural network fault diagnosis system [7].…”

Nonlinear Unknown Input Observer Design for Nonlinear Systems: A New Method

“…For that type of system, an observer, which has the capability of estimating the states in the presence of unknown inputs, is required in order to design an appropriate control for the system. Such a problem arises in systems subject to disturbance or with inaccessible inputs and it may appear in many applications such as fault detection and isolation or parameter identification, see Mondal et al (2009). Design of observers for linear systems subject to unknown inputs has attracted considerable attention in the last three decades.…”

Fault‐Reconstruction‐Based Cascaded Sliding Mode Observers for Descriptor Linear Systems

“…1 where x 1 , x 2 , x 3 , and x 7 are the generator angles, x 4 , x 5 , and x 6 are the generator speeds. u 1 , u 2 , and u 3 are the mechanical power, P ch is unknown load, the nominal values of inertia M 1 , M 2 and M 3 , of damping D 1 , D 2 , and D 3 , of admittance Y 15 , Y 25 , Y 35 , Y 51 , Y 52 , Y 53 , and Y 54 and of potentialV 1 , V 2 , V 3 , V4 , and V 5 are shown in…”