Study on Simulation Analysis of Secondary Board Card with Multi-Physical Field Coupling

To predict and evaluate the change model of secondary board card which is sensitive to various physical fields such as temperature and stress, this paper conducted a thorough research on the simulation technology with multi-physical field coupling for the secondary board card, around the practical need to improve the reliability in MMC (modular multilevel converter) which is a component in flexible DC transmission system. According to the characteristics of MMC secondary board card, it was studied on the coupling mechanism between temperature and vibration, and an analysis approach of thermal-structural coupling was proposed. Based on this approach, an analysis application concerned thermal vibration coupling was developed, and a unit control board from MMC power module was adopted in thermal-structural simulation tests. The design defects of secondary board card were discovered, and corresponding suggestions were put forth. All these test results demonstrate that the reliability level of MMC secondary board card can be effectively improved by the proposed method - simulation test of multi-physical field coupling.