Output overload and fault tolerant commutation method for a switched reluctance generator and an electric power generating system employing same

Claim 3

The method of claim 1, further comprising the step of closing both the upper and lower switches if the monitored current falls below a second predetermined value.

Claim 4

The method of claim 1, further comprising the step of monitoring an angle between the rotor pole and the stator pole.

Claim 5

The method of claim 3, wherein step A) is accomplished at a fixed angle prior to alignment of the rotor and stator pole.

Claim 6

The method of claim 3, wherein step D) is accomplished at a fixed angle after alignment of the rotor and stator pole.

Claim 7

The method of claim 3, wherein step E) is accomplished at a fixed angle during a period of non-alignment of the rotor and stator pole.

Claim 8

The method of claim 1, further comprising the step of monitoring a voltage on the bus capable of supplying electric power to utilization equipment; and varying the first predetermined value inversely to a variation in the monitored voltage.

Claim 11

The method of claim 8, further comprising the steps of monitoring current flow through the stator winding, and freewheeling the stator winding during the first phase if the monitored current exceeds a first current limit.

Claim 12

The method of claim 8, further comprising the steps of monitoring current flow through the stator winding, and exciting the stator winding during the third phase if the monitored current falls below a second current limit.

Claim 13

The method of claim 8, wherein said first phase begins at a fixed angle prior to alignment of the rotor and stator poles.

Claim 14

The method of claim 11, wherein said first phase ends at a fixed angle after alignment of the rotor and stator poles.

Claim 15

The method of claim 8, wherein said second phase begins at a fixed angle after alignment of the rotor and stator poles.

Claim 16

The method of claim 13, wherein said second phase ends at a fixed angle during a period of non-alignment of the rotor and stator poles.

Claim 17

The method of claim 8, wherein said third phase begins at a fixed angle during a period of non-alignment of the rotor and stator poles.

Claim 18

The method of claim 15, wherein said third phase ends at a fixed angle prior to alignment of the rotor and stator poles.

Claim 19

An electric power generating system, comprising: a switched reluctance machine having a wound stator and a salient pole rotor rotatably mounted therein, said rotor drivably coupled to a source of rotational energy, said stator having a plurality of poles wound with a winding to form pole pairs; a power bus having a positive feeder and a return; first switching means switchably coupling a first end of said winding to said positive feeder of said power bus; second switching means switchably coupling a second end of said winding to said return of said power bus; a first commutation means coupled between said second end of said winding and said positive feeder of said power bus; a second commutation means coupled between said first end of said winding and said return of said power bus; voltage sensing means in sensor communication with said positive feeder of said power bus for monitoring a voltage level thereon, said voltage sensing means generating a monitored voltage signal indicative of said monitored voltage; current sensing means in sensory communication with said winding for monitoring a flow of current therethrough, said current sensing means generating a monitored current signal indicative of said monitored current; rotor position sensing means for monitoring an angular position of said rotor, said rotor position means generating a monitored angle signal indicative of said rotor angular position; and a controller responsive to said monitored voltage, current, and angle signals for commutating said switched reluctance machine in a generate mode, said controller commanding said first and said second switching means closed at a fixed angle prior to alignment of said rotor and said stator pole, said controller thereafter commanding said first and said second switching means open at a fixed angle after alignment of said rotor and said stator poles, said controller thereafter commanding one of said first and said second switching means closed at a fixed angle of non-alignment of the rotor and stator poles for substantially a whole period of non-alignment of the rotor and stator poles.

Claim 20

An electric power generating system, comprising: a switched reluctance machine having a wound stator and a salient pole rotor rotatably mounted therein, said rotor drivably coupled to a source of rotational energy, said stator having a plurality of poles wound with a winding to form pole pairs; a power bus having a positive feeder and a return; first switching means switchably coupling a first end of said winding to said positive feeder of said power bus; second switching means switchably coupling a second end of said winding to said return of said power bus; a first commutation means coupled between said second end of said winding and said positive feeder of said power bus; a second commutation means coupled between said first end of said winding and said return of said power bus; voltage sensing means in sensor communication with said positive feeder of said power bus for monitoring a voltage level thereon, said voltage sensing means generating a monitored voltage signal indicative of said monitored voltage; current sensing means in sensory communication with said winding for monitoring a flow of current therethrough, said current sensing means generating a monitored current signal indicative of said monitored current; rotor position sensing means for monitoring an angular position of said rotor, said rotor position means generating a monitored angle signal indicative of said rotor angular position; and a controller responsive to said monitored voltage, current, and angle signals for commutating said switched reluctance machine in a generate mode, said controller commanding said first and said second switching means closed at a fixed angle prior to alignment of said rotor and said stator pole, said controller thereafter commanding said first and said second switching means open at a fixed angle after alignment of said rotor and said stator poles, said controller thereafter commanding one of said first and said second switching means closed at a fixed angle of non-alignment of the rotor and stator poles for substantially a whole period of non-alignment of the rotor and stator poles.

Claim 21

The system of claim 17, wherein said controller maintains a current flow through said winding at all times during operation by commanding both said first and said second switching means closed when said monitored current droops below a lower current limit.

Claim 22

The system of claim 18, wherein said controller commands one of said first and said second switching means open when said monitored current exceeds an upper current limit.

Claim 23

The system of claim 19, wherein said controller varies said upper current limit inversely with said monitored voltage to regulate said voltage at a desired level.