SATELLITE INCLUDING CROSSOVER POWER PROCESSING UNITS FOR ELECTRIC THRUSTERS

Abstract

A spacecraft propulsion system including a first thruster system including a first power processing unit connected to a first thruster string via a crossover switching unit and connected to a second thruster string via the crossover switching unit. A second thruster system including a second power processing unit connected to the second thruster string via the crossover switching unit and to the first thruster string via the crossover switching unit. A controller is connected to each of the first power processing unit, the second power processing unit, and the crossover switching unit.

Description

Claims

1. A spacecraft propulsion system comprising: a first thruster system including a first power processing unit connected to a first thruster string via a crossover switching unit and connected to a second thruster string via the crossover switching unit;a second thruster system including a second power processing unit connected to the second thruster string via the crossover switching unit and to the first thruster string via the crossover switching unit; anda controller connected to each of the first power processing unit, the second power processing unit, and the crossover switching unit.

2. The spacecraft propulsion system of claim 1, wherein the first thruster string and the second thruster string each include at least two thrusters.

3. The spacecraft propulsion system of claim 2, wherein the at least two thrusters in each of the first thruster string and the second thruster string are electric thrusters.

4. The spacecraft propulsion system of claim 3, wherein the at least two thrusters in each of the first thruster string and the second thruster string are hall effect electric thrusters.

5. The spacecraft propulsion system of claim 1, wherein the crossover switching unit includes a first plurality of switches, each of the switches in the first plurality of switches being one of a mechanical contactor, a relay, a latching relay and a solid state switch and the crossover switching unit includes a second plurality of switches, each of the switches in the second plurality of switches being one of a mechanical contactor, a relay, a latching relay and a solid state switch.

6. The spacecraft propulsion system of claim 5, wherein each switch in the first plurality of switches and the second plurality of switches is a latching relay.

7. The spacecraft propulsion system of claim 6, wherein the first plurality of switches in the crossover switching unit and the second plurality of switches in the crossover switching unit are approximately identical.

8. The spacecraft propulsion system of claim 6, wherein the crossover switching unit includes seven latching relays per thruster in the corresponding thruster string.

9. The spacecraft propulsion system of claim 1, wherein the controller includes a control module configured to demultiplex an output of one of the first power processing unit and the second power processing unit using the crossover switching unit, such that the first power processing unit provides output signals to the first thruster string and the second thruster string.

10. A method for providing crossover redundancy in a spacecraft propulsion system comprising: connecting a first power processing unit to a first thruster string using a crossover switching unit and to a second thruster string using the crossover switching unit;connecting a second power processing unit to the first thruster string using the crossover switching unit and to the second thruster string using the crossover switching unit; andcontrolling the crossover switching unit with a controller such that the first power processing unit signals are passed through the crossover switching unit to the first thruster string and the second power processing unit signals are passed through the crossover switching unit to the second thruster string.

11. The method of claim 10 further comprising: controlling the crossover switching unit with the controller such that the crossover switching unit demultiplexes signals from the first power processing unit to the first and second thruster strings in response to a fault in the second power processing unit.

12. The method of claim 10, wherein controlling the crossover switching unit with a controller includes commanding a state of each switch in a first plurality of switches within the crossover switching unit and commanding a state of each switch in a second plurality of switches within the crossover switching unit using the controller.

13. The method of claim 12, further comprising latching each switch in the first plurality of switches and latching each switch in the second plurality of switches such that continued commands from the controller are not required to maintain a desired switch state.

14. The method of claim 13, wherein each switch in the first plurality of switches and each switch in the second plurality of switches is a latching relay.

15. The method of claim 10, wherein the crossover switching unit includes a first plurality of switches and a second plurality of switches, and wherein each plurality switches includes at least one of a mechanical contactor, a relay, a latching relay and a solid state switch.

16. The method of claim 10, wherein controlling the crossover switching unit with the controller comprises connecting each power processing unit to the corresponding thruster string as a single unit.

17. The method of claim 10, wherein controlling the crossover switching unit with the controller comprises connecting each power processing unit to each thruster in the corresponding thruster string independently.