A 3.3-kV All Silicon Carbide Module based Ultra-High-Density Building Block Concept for Multi-Megawatt Traction Applications

In the megawatt (MW) scale high-power traction applications, such as the large mining trucks and rail transport systems, silicon based IGBTs have been the pronounced solution for many years. With the increasing demand for higher power ratings and power density with enhanced system performance, the movement towards utilizing faster and more efficient silicon carbide (SiC) MOSFETs is only growing stronger. In this work, a 3.3-kV high-current SiC module-based building block concept with ultra-high power density for the MW traction applications is presented. To fully exploit the benefits of the 3.3-kV SiC modules in the 140 mm × 100 mm industrial package, a low inductance and ultra-compact system design is presented, including the laminated bussing structure, low inductance capacitor bank and a double-sided cold plate to hold 4× power modules. The presented building block can be used to develop a 3-phase traction inverter to drive one, two, or four MW-class traction motors, enabling a versatile modular solution. It is also feasible to use it as a building block to enable direct connection to medium-voltage grid. Detailed analysis are presented for these use cases and preliminary testing results are presented to validate the feasibility.