Design and validation of a dual-functional damper based on a stepper motor for energy harvesting and vibration control

Abstract

Dampers are widely used to reduce undesired vibrations. In recent decades, they have been developed from the energy dissipation strategy to the energy harvesting strategy. Dual-functional dampers, which convert part of vibration energy into electrical energy, are intensively studied. DC motors are the most applied electromagnetic transducers in these studies. In this paper, two-phase stepper motors are applied as adjustable electrical dampers and energy harvesters. Dual-functional dampers using stepper motors inherently have higher damping density than those using DC motors, as stepper motors have more pole pairs than DC motors. The nonlinear theoretical electrical damping coefficient of two-phase stepper motors is derived and compared with that of DC motors. A dual two-stage Energy Harvesting Circuit (EHC) is proposed to realize the function of adjustable electrical damping through resistance emulation and the function of harvesting energy. A test bench is built to experimentally verify the adjustable electrical damping and energy harvesting performance of a selected two-phase hybrid stepper motor with the proposed dual two-stage energy harvesting circuit. The numerical solution from the identified model shows a high agreement with the experimental results. The energy harvesting efficiency in the electrical domain has reached about 85%. This tested dual-functional damper using a stepper motor has been successfully integrated into a full-scale demonstrator of the distributed-Multiple Tuned Facade Damping (d-MTFD) system.