The invention concerns a converter as well as a cooling device and a method for cooling at least a first and a second group of electrically interconnected electrical components (SWA1, SWA2, SWA3, SWA4, SWA5, SWA6, SWA7, SWA8, SWB1, SWB2, SWB3, SWB4, SWB5, SWB6, SWB7, SWB8) in the converter, where the first and second groups are placed on opposite sides of a conductor leading to a connection terminal of the converter. The cooling device (22) comprises a first transporting arrangement (HSA1, HSA2, HSA3, HSA4, HSA5, HSA6, HSA7, HSA8, HSA9, COA1, COA2, COA3, COA4, COA5, COA6, COA7, COA8) transporting cooling medium (M) past the first group and a second transporting arrangement (HSB1, HSB2, HSB3, HSB4, HSB5, HSB6, HSB7, HSB8, HSB9, COB1, COB2, COB3, COB4, COB5, COB6, COB7, COB8) transporting the same cooling medium past the second group.