In this paper, we propose a global exponential adaptive observer for a class of uniformly observable nonlinear systems. This observer, based on techniques of high gain, is applied to jointly estimate missing states (rotor flux components) and unknown constant parameters incorporating in their expressions different electric parameters of an asynchronous motor. Finally, the feasibility of the pro...

In this paper the problem of inputs in observer design for systems which are not uniformly observable is considered. It is emphasized how it amounts to a control problem, which can be solved in a general way by some appropriate optimization approach. This is illustrated on the basis of a quite general Kalman-like observer form possibly with high gain, as well as related simulation results on an...

For joint estimation of state variables and unknown parameters, adaptive observers usually assume some persistent excitation (PE) condition. In practice, the PE condition may not be satisfied, because underlying recursive problem is ill-posed. To remedy lack condition, inspired by ridge regression, this paper proposes a regularized observer with enhanced parameter adaptation gain. Like in typic...

We introduce a method of observer design for systems described by a linear part with a nonlinear perturbation, where the perturbation is parameterized by a vector of unknown, constant parameters. The design is modular, and consists of a modified high-gain observer that estimates the states of the system together with the full perturbation, and a parameter estimator. The parameter estimator is c...

A full-order observer accomplishes its purpose by calculating the “residual,” which is the difference between the measured output and the corresponding quantity generated by a model of S synthesized in the observer. The residual, multiplied by a “gain” is used as an input to a model of S . If the gain is chosen appropriately, the observer Ŝ will be an asymptotically stable dynamic system and th...

A robust high gain observer for state and unknown inputs/faults estimations for a special class of nonlinear systems is developed in this article. Ensuring the observability of the faults/unknown inputs with respect to the outputs, the faults can be estimated from the sliding surface. Under a Lipschitz condition for the nonlinear part, the high gain observers are designed under some regularity ...

in this paper, a dc-dc resonant converter with high voltage gain and small size is studied. to reduce the size and weight of this converter, the operating frequency should be as high as possible. in this research, the frequency changes from 120 to 200 khz. due to the high operating frequency, it is necessary to reduce the switching losses using soft switching methods. resonant converters are su...

In this paper, we investigate the event-triggered consensus problems of nonlinear strict feedback MASs under directed graph. Based on high-gain control technique, firstly give a state-based algorithm and prove that Zeno behavior can be excluded. When full state information is unavailable, observer given to estimate each agent an observer-based developed. Finally, example verify effectiveness bo...