Abstract: An arrangement for cooling power semiconductor devices (2) of a converter (1) arranged in a closed casing (3) with the semiconductor devices in a bottom of the casing on top of a heat sink (5) having members (6) for heat exchange extending externally of the casing out from the bottom comprises a channel (8) for conducting a flow of air to pass said members (6) for cooling thereof, in which a first portion (7) of the channel has the casing bottom as a ceiling and receiving said members (6). A fan (9) is located with a suction side connected to the first channel portion (7) to create a flow of air from an inlet (16) from the exterior (19) into the channel while passing the heat sink members. A filter (18) covers the inlet to the channel for removal of dust and debris from air entering the channel from the exterior.

Abstract: An arrangement for cooling power semiconductor devices (2) of a converter (1) arranged in a closed casing (3) with the semiconductor devices in a bottom of the casing on top of a heat sink (5) having members (6) for heat exchange extending externally of the casing out from the bottom comprises a channel (8) for conducting a flow of air to pass said members (6) for cooling thereof, in which a first portion (7) of the channel has the casing bottom as a ceiling and receiving said members (6). A fan (9) is located with a suction side connected to the first channel portion (7) to create a flow of air from an inlet (16) from the exterior (19) into the channel while passing the heat sink members. A filter (18) covers the inlet to the channel for removal of dust and debris from air entering the channel from the exterior.