Abstract:
Prior generating systems utilizing electrically-compensated constant speed drives (ECCSD) have typically required a separate starter motor for starting a prime mover which supplies motive power to the ECCSD, thereby increasing the size and weight of the system. In order to overcome this problem, a generating system is provided with circuitry coupled to the electrical power windings of a permanent magnet machine (PMM) forming a part of the ECCSD for causing the PMM to develop motive power which causes an output shaft of a differential of the ECCSD to rotate at increasing speeds. When the output shaft of the differential reaches a predetermined speed, a generator (12) coupled to the output shaft of the differential is supplied external or ground power which in turn causes the generator (12) to operate as a motor and return motive power (16) through the differential to the prime mover to start same and bring it up to operating speed.
Abstract:
Prior generating systems utilizing electrically-compensated constant speed drives (ECCSD) have typically required a separate starter motor for starting a prime mover which supplies motive power to the ECCSD, thereby increasing the size and weight of the system. In order to overcome this problem, a generating system is provided with circuitry coupled to the electrical power windings of a permanent magnet machine (PMM) forming a part of the ECCSD for causing the PMM to develop motive power which causes an output shaft of a differential of the ECCSD to rotate at increasing speeds. When the output shaft of the differential reaches a predetermined speed, a generator (12) coupled to the output shaft of the differential is supplied external or ground power which in turn causes the generator (12) to operate as a motor and return motive power (16) through the differential to the prime mover to start same and bring it up to operating speed.
Abstract:
Electrically compensated constant speed drives develop constant speed motive power from variable speed motive power developed by a prime mover (16) so as to enable generation of constant frequency power by means of a main generator (12) coupled thereto. However, there is no provision in such drives for degeneration of emergency power in the event of a fault in the generator (12). In order to overcome this problem, an emergency power generating system includes an emergency power converter (84) which is selectively coupled to the output of a permanent magnet machine (PMM1) forming a part of the constant speed drive (11) when a main generator (12) failure occurs so that the permanent magnet machine (PMM1) and the emergency power converter (84) provide emergency power to one or more loads.