Various embodiments of the invention include systems, computer program products, and related methods for managing the purging of a hydrogen-cooled dynamoelectric machine. In various embodiments, a system is disclosed including at least one computing device configured to perform the following: obtain an indication of a fault in an alternating current (AC) power supply to a hydrogen-cooled dynamoelectric machine system; determine a reserve power characteristic of a reserve energy storage device in response to obtaining the indication of the fault in the AC power supply; and extend a pre-purge cycle for the hydrogen-cooled dynamoelectric machine system based upon the reserve power characteristic of the reserve energy storage device.