In this paper a new excitation control scheme that improves the transient stability of multimachine power systems is proposed. To this end the backstepping technique is used to transform the system to a suitable partially linear form. On this system, a combination of both feedback linearization and adaptive control techniques are used to confront the nonlinearities. As shown in the paper, the r...

A direct adaptive neural network tracking control scheme is presented for a class of nonaffine nonlinear systems with zero dynamics. The method does not assume boundedness on the time derivative of a control effectiveness term. Parameters in neural networks are updated using a gradient descent method which designed in order to minimize a quadratic cost function of the error between the unknown ...

Approximate/adaptive dynamic programming (ADP) has been studied extensively in recent years for its potential scalability to solve large state and control space problems, including those involving continuous states and continuous controls. The applicability of ADP algorithms, especially the adaptive critic designs has been demonstrated in several case studies. Direct heuristic dynamic programmi...

In this paper, a robust adaptive control scheme is proposed for robot manipulators. The structure of controller is based on the regressor-based form of the robot model. The presented control scheme does not require a priori any knowledge for uncertainty bounds. The global stability of the closed-loop system is guaranteed by using the Lyapunov stability approach. Furthermore, in the presence of ...

In this paper a new excitation control is developed for multimachine power systems that improves the transient stability. The design is based on the sliding mode technique which is applied on an equivalent model of the system obtained by using the backstepping technique. However, the conventional “sign” method with constant gains is replaced by the boundary layer sliding mode technique with tim...

In this paper, a direct adaptive neural control scheme with sliding mode method is presented for a class of switched nonlinear systems which is in the presence of model uncertainties and external disturbances. A sliding mode controller based on RBF neural networks (RBF NNs) which are utilized to approximate unknown functions and uncertain nonlinear terms is designed to enhance robustness and ma...

In this paper, piecewise linear switched systems affected by both parameter variations and exterior disturbances are considered. The problem of synthesis of switching laws, which assure that the system state is ultimately bounded within a given compact set containing the origin with an assigned rate of convergence, is investigated. Given an uncertain switched linear system, we present a systema...

The L (1 < p < ∞) and weak-L estimates for the variation for CalderónZygmund operators with smooth odd kernel on uniformly rectifiable measures are proven. The L boundedness and the corona decomposition method are two key ingredients of the proof.

MThe study of equations (1) and (2) has fallen into two cases: first, the case where ƒ (x) ^ 0 for all x, and secondly, the case where ƒ (x) < 0 for \x\ small. The best results for the first case were given by Burton and Townsend [ l ] in the form of necessary and sufficient conditions for boundedness and oscillation of solutions of (1) in the case xg(x) > 0 for xjéO. The results to be describe...