Abstract: In this paper, a decentralized control problem is considered for multimachine power systems with nonlinear interconnections and disturbances. A direct feedback linearization compensator is employed to cancel most of the nonlinearities, and then a backstepping procedure is applied to deal with the interconnections and to reduce the effects of a disturbance that does not satisfy the mat...

Stability analysis of linear periodically time-varying systems via integral quadratic constraints is extended to the problem of control design. A full-state feedback controller that satis5es exponential stability and L2-gain disturbance attenuation from an external disturbance to a controlled output is designed for linear systems with periodically time-dependent system matrices. The main result...

Diversity is often associated with the functional stability of ecological communities from microbes to macroorganisms. Understanding how diversity responds to environmental perturbations and the consequences of this relationship for ecosystem function are thus central challenges in microbial ecology. Unimodal diversity-disturbance relationships, in which maximum diversity occurs at intermediate...

electric wheelchairs (ew) experience various terrains surfaces and slopesas well asoccupants with diverse weights. this, in turn, imparts a substantial amount of perturbation to the ewdynamics. in this paper we make use of a two-degree-of-freedom control architecture called disturbance observer (dob) which reduces sensitivity to model uncertainties while enhancing rejection of disturbances caus...

A two-degree-of-freedom Smith control scheme is proposed for improved disturbance rejection for stable delay processes. The resulting set-point and disturbance responses can be tuned by two controllers separately. A novel disturbance controller design is presented with easy tuning and greatly improved performance. The internal and robust stability issues are discussed. Examples are provided for...

More diverse communities are thought to be more stable-the diversity-stability hypothesis-due to increased resistance to and recovery from disturbances. For example, high diversity can make the presence of resilient or fast growing species and key facilitations among species more likely. How natural, geographic biodiversity patterns and changes in biodiversity due to human activities mediate co...

The response of hypersonic boundary layer over a blunt wedge to freestream pulse acoustic disturbance was investigated. The stability characteristics of boundary layer for freestream pulse wave and continuous wave were analyzed comparatively. Results show that freestream pulse disturbance changes the thermal conductivity characteristics of boundary layer. For pulse wave, the number of main dist...

This paper proposes a new approach to disturbance estimation based on a curvature model to improve the disturbance rejection performance of a servo system. The main feature is that the stability of the control system is guaranteed when the disturbance estimation is incorporated directly into the designed control law. Simulation results show that disturbances are rejected efficiently when this a...

This paper studies the problem of disturbance attenuation with internal stability via output feedback for a family of nonlinear systems. Using a feedback domination design which substantially differs from the separation principle, we explicitly construct a dynamic output compensator attenuating the disturbance’s effect on the output to an arbitrary degree of accuracy in the L2-gain sense, and a...

Most of the practical systems are having uncertainty which makes it difficult to maintain stability and better performance. In this paper a robust controller design, based on the quantitative feedback theory (QFT) is proposed for a nonlinear process like Spherical tank system and bioreactor. The QFT controller is designed to ensure the robust stability and performance (input and output disturba...