Cable Mr Semi-active Control Methods Research

Due to the small mass, low damping and large flexibility, stay cables are susceptible to large amplitude of vibration with different mechanism caused by rain-wind induced vibration and seismic load, which will cause serious damage to the structural quality. Therefore, how to mitigate the vibration of stay cables is of great importantance in practice.Passive control of cable vibration suppression lacks of adaptability in different dynamic response. The application of active control is impeded by the fatigue damage in the damper location of actuator and high cost of the investment. Because of the weakness of passive control and active control, magnetorheological damper are widely used in civil engineering applications, and the semi-active control technologies have attracted wide research. One challenge in the use of semi-active is the choice of an appropriate algorithm.According to the cable vibration theory, the model of cable magnetorheological damper system is established, which takes the Irvine parameter into account. Furtherly, using the LuGre dynamic friction model to describe the magnetorheological damper behavior, a new model of cable-magnetorheological damper system is established. The resulting model provides a good description of system dynamic characteristics. Firstly, for the new model of cable-damper system, a semi-active adaptive control law, which is achieved using lyapunov direct method, is presented to suppress the vibration of stay cables. Secondly, a singular perturbation analysis allows to reduce the new model and another semi-active adaptive control law is abtained. Using the root mean square RMS and midpoint displacement, that is more comprehensive application in engineering, to measure the damper performance. The analysis results of numerical simulations show that the proposed control laws can effectively mitigate vibration of stay cables, and the control effect will increase with the the rise of damper location. In addition, the semi-active adaptive control law, based on singular perturbation analysis, can better decrease vibration of the system and meet the engineering requirement.