In a context where the demand for clean and efficient energy is constantly growing, power components are essential. Diamond transistors, with their wide bandgap, offer significant advantages over traditional silicon-based technologies, including superior efficiency, increased power density, and better performance at high temperatures. They are ideal for energy converters, battery management systems, and high-frequency switching devices. The objective of this thesis is to characterize the electrical properties of diamond as a function of temperature to anticipate its behavior in future power applications. This research, utilizing the platforms of CEA Occitanie and LAAS-CNRS, aims to evaluate component losses, control techniques, and self-heating effects, while addressing thermal management and packaging through 3D ceramic structures. The results could transform energy conversion technologies and systems requiring robust and efficient components at high temperatures.