Improving Reliability of an Automotive Power Electronic Unit Using Locally Resonant Metamaterials

The transition from internal combustion to electric vehicles requires assessing new challenges posed by novel components, materials, and manufacturing processes. These include assessing new types of excitations and damages from a reliability perspective. This paper investigates a solution to enhance Printed Circuit Board (PCB) reliability within automotive Power Electronic Units (PEUs). Controlling vibration levels is crucial to prevent component breakage and PEU failure. The proposed approach exploits Locally Resonant Metamaterials (LRMs) to reduce PCB vibrational loads. LRMs provide excellent Noise, Vibration, and Harshness (NVH) performance within specific frequency ranges while being lightweight and providing high design freedom. Since direct integration into the PCB is unfeasible, the aluminum spider frame securing the PCB is treated instead. Previous simulations demonstrated significant vibrational load reduction. In this study, the LRM solution is fabricated, and experimental validation is performed using a shaker test mimicking operating conditions. Multiple configurations are explored: two concepts tuned to individual PEU resonance frequencies, and a hybrid configuration targeting both peaks simultaneously. Finally, relative damage is calculated using experimental data, comparing configurations with and without the LRM solution, demonstrating how this method can evaluate the LRM solution's performance in such applications.