Feasibility Study of a Self-powered Magnetorheological Damper for Vibration Control of a Stay Cable

A new self-powered magnetorheological (MR) damper control system is first integrated based on energy harvesting technology, in which the power source of a MR damper is provided by a rotational permanent magnet direct current(DC) generator harvesting from structural vibration energy. Then, the presented self-powered MR damper is applied to control vibrations of a 21.6m-long cable in the laboratory. The test results show that the modal damping ratios of the cable in the first four modes can be improved dramatically by the developed self-powered MR damper. Moreover,the control performance with the self-powered MR damper is independent of the cable's vibration level. Moreover, the control mechanisms of the self-powered MR damper are investigated. It is found that, on one hand, the self-powered MR damper works as the linear viscous damper so that it won't lock the cable even when the cable vibrates with small amplitude, and on the other hand, it also can natively realize the negative stiffness control,which can greatly enhance the control performance.