摘要 |
An air cooled electric machine, such as an alternating current motor, having a housing containing a rotating shaft and a housing airflow cooling path has cooling vents on the housing periphery. An external cooling system having a duct enclosure is coupled to the housing exterior, and defines a duct airflow cooling path that is in communication with the housing airflow cooling vent and housing airflow cooling path. A duct fan within the duct enclosure external the housing is coupled to and driven by the shaft. The duct fan circulates air at above ambient pressure into the housing airflow cooling path. |