Oscillation control of a pendulum structure using an inverted pendulum-type tuned mass damper

In reality, a pendulum structure can be used to model many real structures as a ropeway carrier, crane, balloon basket or ships in waves, etc, which often hung on moving points such as cables, wavefronts and balloons, etc. To the best knowledge of the author, however, there is no study to control oscillation of the pendulum structure excited by the hanging point. Therefore, this article deals with the oscillation control of the pendulum structure by using an inverted pendulum-type tuned mass damper, in which the system is subjected to the motion of the hanging point. In particular, the optimal parameters are determined in clear analytical solutions, making it easy for scientists to determine the optimal parameters to suppress the oscillation for the pendulum structure.

Payload oscillation control of tower crane using smooth command input

This paper presents a smooth command (SC) input shaper for suppressing payload oscillations in rest-to-rest simultaneous radial and tangential motions of a tower crane. The radial and tangential acceleration profiles of the compound motions are represented by multi-sine wave functions with independent and variable maneuvering time. The proposed SC is designed using a nonlinear mathematical model of the tower crane while the parameters of the acceleration profiles and maneuvering times were optimized using a particle swarm algorithm (PSO). The simulated results were verified experimentally on a laboratory scale tower crane. The results confirm that the proposed SC input effectively canceled residual vibrations of the payload compound motions with a time length comparable to zero vibrations (ZV) shaper. Moreover, sensitivity analysis to variations in cable length reveals that the proposed command input is robust over a wide range of cable lengths.

Development and Research of Motion Control Algorithms of Elastic Electromechanical Systems Taking into Account the Damping Properties of the Electric Drive

The paper presents the results of studies of the effect of the counter-electromotive force (CEMF) of the dc machine on the parameters of the elastic oscillation control system of a two-mass electromechanical system, synthesized based on of solving the inverse problems of dynamic in accord with prescribed nature of controlled motion. It is shown by the method of numerical simulation that taking into account the CEMF leads to an increase of the damping properties of the electromechanical system and an increase of the gains of the feedbacks on the force in the cable. A method for the selection of these gains is proposed, based on their comparison with the gains obtained in an electromechanical system without taking into account the CEMF and an approximate assessment of its effect on the nature of the transient processes.

Fractional-Order Hyperbolic Tangent Sliding Mode Control for Chaotic Oscillation in Power System

Chaotic oscillation will occur in power system when there exist periodic load disturbances. In order to analyze the chaotic oscillation characteristics and suppression method, this paper establishes the simplified mathematical model of the interconnected two-machine power system and analyzes the nonlinear dynamic behaviors, such as phase diagram, dissipation, bifurcation map, power spectrum, and Lyapunov exponents. Based on fractional calculus and sliding mode control theory, the fractional-order hyperbolic tangent sliding mode control is proposed to realize the chaotic oscillation control of the power system. Numerical simulation results show that the proposed method can not only suppresses the chaotic oscillation but also reduce the convergence time and suppress the chattering phenomenon and has strong robustness.