Design methodology for the co-design of mechanical structure and interface circuitry of electrodynamic energy harvesters

• Applicants: Dr. Thorsten Hehn; Professor Dr.-Ing. Ralf Sommer
• Subject Area: Microsystems
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 452215927

Using energy harvesting, ambient energy can be converted to electrical energy in order to operate energy-autonomous wireless sensor nodes, for example. This opens up numerous new possibilities for applications such as Industry 4.0 or the Internet of Things, where many sensors are needed in decentralized locations. The energy supply via battery or cable causes high maintenance and installation costs and should therefore be avoided. For this reason, energy harvesting has the potential to become a key technology for the establishment of sensor applications.In the described research project, a co-design of mechanics and electronics for electromechanical vibration harvesters will be developed. For the considered electrodynamic energy harvesters, the optimal harvesting system for given requirements should therefore be developed. This extends the state of the art where harvesters and interface electronics are developed separately, which results in the non-utilization of the synergies of mechanics and electronics and thus leads to a suboptimal overall system.The approach here is to consider the interaction of electronics and mechanics already in the design phase by appropriate modeling in order to be able to use synergy effects. By means of an optimization algorithm an optimal overall concept, consisting of harvester topology and interface circuit topology including parameter determination, can be generated for the given conditions such as signal shape, frequency and amplitude of the excitation, size of the harvester etc.For this purpose, an appropriate overall modeling must be developed in which both the mechanics and the electronics can be represented. In addition, it should also be possible to integrate other physical domains such as magnetism. Different modelling approaches have to be evaluated and examined for their suitability. In addition, the optimal abstraction level has to be determined so that the dominant effects are considered sufficiently accurately, but without creating a too computationally intensive modelling, as is the case, for example, with the mapping of the electronics on transistor level or the mapping of the mechanics on the level of a finite element modeling. In addition, it should be possible to consider the influence of the process variation for the mechanics, similar to what is already standard in electronics.To validate the results, the optimization tool developed here will be used to develop, manufacture and measure a corresponding overall system consisting of a miniaturized harvester and interface ASIC for given requirements.

• DFG Programme: Research Grants