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This paper presents a unique Virtual Prototyping Process (VPP) that allows for metaheuristic optimization of the building block based Power Electronic Converter systems. The VPP allows for exploration of a range of design space variables, including voltage levels, power semiconductor device technology and thermal management approach against competing objectives such as power density, efficiency and specific cost given electrical and environmental constraints. A unique feature of proposed VPP is compilation of lower voltage building blocks into a much higher voltage rated system and inclusion of allocations for insulation systems, thermal management, accessibility, busing/interconnections and frame/structure/chassis. This approach enables understanding of these practical considerations on power density. This paper presents a use case of a Medium Voltage ac (MVac) to Low Voltage dc (LVdc) solid state transformer. 

Thin‐film neural devices are an appealing alternative to traditional implants, although their chronic stability remains matter of investigation. In this study, a chronically stable class of thin‐film devices for electrocorticography is manufactured incorporating silicon carbide and diamond‐like carbon as adhesion promoters between glassy carbon (GC) electrodes and polyimide and between GC and platinum traces. The devices are aged in three solutions—phosphate‐buffered saline (PBS), 30 × 10⁻³and 150 × 10⁻³mH₂O₂/PBS—and stressed using cyclic voltammetry (2500 cycles) and 20 million biphasic pulses. Electrochemical impedance spectroscopy (EIS) and image analysis are performed to detect eventual changes of the electrodes morphology. Results demonstrate that the devices are able to undergo chemically induced oxidative stress and electrical stimulation without failing but actually improving their electrical performance until a steady state is reached. Additionally, cell viability tests are carried out to verify the noncytotoxicity of the materials, before chronically implanting them into rat models. The behavior of the GC electrodes in vivo is monitored through EIS and sensorimotor evoked potential recordings which confirm that, with GC being activated, impedance lowers and quality of recorded signal improves. Histological analysis of the brain tissue is performed and shows no sign of severe immune reaction to the implant.