Modeling Approach and Degradation Parameters Identification for Half-Bridge Module Based on Digital Twin Theory

In future high voltage direct current transmission (HVDC), the half-bridge (HB) module features as the fundamental analyzing unit for assessing the operation, health status, and potential risks of the HVDC system. However, the conventional electrical model is no longer adequate for the demands of sophisticated power electronic systems. Therefore, based on the digital twin theory, a modeling approach and a degradation parameters identification method for the HB module are proposed in this paper. First, the interface between the digital twin system and the physical system is presented. Then, the detailed multiphysics mechanisms of IGBT and Al-caps are revealed. and the data-driven method is implemented for degradation parameters identification. Finally, a prototype with three HB modules is built up, and experiments demonstrate that the digital twin system closely resembles the physical system, capable of identifying degradation parameters that were previously unattainable.