Electromagnetic Energy-Harvesting Damper With Multiple Independently Controlled Transducers: On-Demand Damping and Optimal Energy Regeneration

An active or semiactive dampers can change its damping property to maintain the tradeoff between ride quality and road handling; however, semiactive dampers need external power supply and active dampers even require considerable power consumption. A regenerative damper has the ability of tuning the damping without the requirement of an external power supply. The aim of this study is to investigate a novel method to conveniently adjust the on-demand damping according to road condition by regenerating vehicle vibration to electricity. In this paper, we propose an electromagnetic energy-harvesting damper with 12 independently-controlled slot winding transducers (SWTs) to investigate the active control method of damping and energy reclaiming from a regenerative damper. By switching on an appropriate number of SWTs and tuning their external resistance to an optimal value, the energy-harvesting damper can both provide on-demand damping and reclaim as much electrical power as possible. Experiments on an MTS testing system showed that both changing the number of switch-on SWTs and tuning their external resistors can adjust the damping coefficient of the energy-harvesting damper, and, hence, the damping tuning can be extended to a large range. The output electrical power was measured on different shunted external resistors, demonstrating that the maximum reclaim of electrical power can be achieved when the shunted resistor is equal to the internal resistance of the SWT. By appropriately arranging the number of switch-on SWTs and their shunted resistors, the electromagnetic energy-harvesting damper can produce on-demand damping, which tuning method is convenient and almost linear. Moreover, thanks to the multiple independently controlled transducers, the proposed energy-harvesting damper can regenerated as much electrical power as possible from the vehicle vibration.