a power electronics system includes a multipart housing having three housing elements of cuboid basic structure to define a central element with inlet and outlet ports for a cooling liquid , an upper and lower cover elements which are arranged on opposite connection surfaces of the central element . a plurality of power electronics switching devices is accommodated in the housing , and a condenser device having condenser connection elements is arranged in the central element of the housing & gt ; further provided is a liquid cooling system having at least one first upper cooling chamber between the central element and the upper cover element , and at least two first and second lower cooling chambers between the central element and the lower cover element . the upper and lower cooling chambers are configured for circulation of the cooling liquid entering through the inlet port and exiting through the outlet port of the housing .