this paper considers the problem of stable limit cycles generating in a class of uncertain nonlinear systems which leads to stable oscillations in the system’s output.this is a wanted behavior in many practical engineering problems. for this purpose, first the equation of the desirable limit cycle is achieved according to shape, amplitude and frequency of the required output oscillations. then,...

A general approach to real-time transient stability control is described, yielding various complementary techniques: pure preventive, open loop emergency, and closed loop emergency controls. The organization of the resulting control schemes is then revisited in order to make it able to cover static and voltage security, in addition to transient stability. Distinct approaches for preventive and ...

this paper proposes a new mixed integer programming model for multi-item capacitated lot-sizing problem with setup times, safety stock and demand shortages in closed-loop supply chains. the returned products from customers can either be disposed or be remanufactured to be sold as new ones again. due to the complexity of problem, three meta-heuristics algorithms named simulated annealing (sa) al...

This paper is concerned with the problem of design and implementation a robust adaptive control strategy for flexible joint electrically driven robots (FJEDR), while considering to the constraints on the actuator voltage input. The control design procedure is based on function approximation technique, to avoid saturation besides being robust against both structured and unstructured uncertaintie...

In disturbance-observer-based control, the closed loop system consists of a main feedback control loop and an inner disturbance observer loop. This paper presents a design method for a disturbance observer to satisfy closed loop performance specifications, provided that the main feedback controller is known. Taking advantage of certain fixedstructure disturbance observers, the disturbance obser...

The paper analyzes global solutions to the optimal digital controller realization problem based on maximizing a finite word length (FWL) closed-loop stability measure. For each closed-loop eigenvalue, a single-pole FWL stability function is first introduced, and a single-pole FWL stability measure is then defined as the maximum of the corresponding single-pole stability function over all the co...

Stability in presence of (possibly varying) time-delays in a control loop consisting of a continuous-time plant and a discrete-time controller is studied. A simple stability criterion is developed, consisting of a graphical test in a Bode plot of the closed loop system. The graphical test makes it very easy to design the controller for time-delay robustness.

The stability, reliability and miniaturization of fiber optic gyroscope (FOG) are always the research focuses and difficulties. This paper presented a hardware design method for the digital closed loop control system of FOG based on FPGA. Based on a large number of experiments, this paper summarized the parameter demands for each module of closed loop control circuit and designed a correspondin...

In this paper the existence of a quadratic control Lyapunov function for bilinear systems is considered. The existence of a control Lyapunov function ensures the existence of a control law which ensures the global asymptotic stability of the closed loop control system. In this paper we will derive conditions for the existence of a control Lyapunov function for bilinear systems. These conditions...