A very thin power conversion unit for equalizing currents through paralleled power modules

Among high power conversion systems, several power modules are often connected in parallel, and ideally should be operated synchronously during their switching. Actually, current imbalances occur due to an asymmetry of current paths on busbars connecting these power modules. This paper deals with the problem of current imbalances between paralleled power modules. First, the general occurrence of imbalanced currents is demonstrated. Next, an original design technique for current equalization in a very thin power conversion unit is presented. Finally, the validity of this proposed principle is shown in simulated results.