Design of electromagnetic energy harvesters for large-scale structural vibration applications

Ian L. Cassidy, Jeffrey T. Scruggs, Sam Behrens, Mehrdad N. Ghasemi-Nejhad
2011 Active and Passive Smart Structures and Integrated Systems 2011  
This paper reports on the design and experimental validation of transducers for energy harvesting from largescale civil structures, for which the power levels can be above 100W, and disturbance frequencies below 1Hz. The transducer consists of a back-driven ballscrew, coupled to a permanent-magnet synchronous machine, and power harvesting is regulated via control of a four-quadrant power electronic drive. Design tradeoffs between the various subsystems (including the controller, electronics,
more » ... hine, mechanical conversion, and structural system) are illustrated, and an approach to device optimization is presented. Additionally, it is shown that nonlinear dissipative behavior of the electromechanical system must be properly characterized in order to assess the viability of the technology, and also to correctly design the matched impedance to maximize harvested power. An analytical expression for the average power generated across a resistive load is presented, which takes the nonlinear dissipative behavior of the device into account. From this expression the optimal resistance is determined to maximize power for an example in which the transducer is coupled to base excited tuned mass damper (TMD). Finally, the results from the analytical model are compared to an experimental system that uses hybrid testing to simulated the dynamics of the TMD. This paper reports on experiments conducted at Duke University in collaboration with the CSIRO Energy Centre, on the design and experimental characterization of an electromechanical transducer capable of generating *
doi:10.1117/12.880639 fatcat:efsq2ekdmza2xjrdnwsnyarmpe