Patent ID: 8339823

Claim:
A multi-cell Voltage Source Converter having at least one phase leg connecting to opposite poles of a direct voltage side of the converter and comprising a series connection of switching elements, each said switching element having on one hand at least two semiconductor chips and on the other at least one energy storing capacitor, a mid point of said series connection forming a phase output being configured to be connected to an alternating voltage side of the converter and to divide the phase leg into an upper valve branch and a lower valve branch, wherein said semi-conductor chips of said switching elements are arranged in stacks comprising each at least two semi-conductor chips, and the converter comprises an arrangement configured to apply a pressure to opposite ends of each said stack for pressing said chips towards each other so as to obtain electric contact between semiconductor chips in said stack, wherein said semiconductor chips have a plate-like structure and are arranged with the large sides thereof directed in the direction of the extension of the stack, at least two semiconductor chips belong to the same switching element and adjacent semiconductor chips belonging to the same switching element are separated by a metal plate sandwiched therebetween for obtaining an electrical connection between the two chips by pressing them against said metal plate.