System and method for isolating sources and loads of a power system

• US 20070274113A1
• Filed: 05/23/2006
• Published: 11/29/2007
• Est. Priority Date: 05/23/2006
• Status: Active Grant

• Current Assignee: Rhombus Energy Solutions, Inc. (BorgWarner Incorporated)
• Original Assignee: EDA IP Holdings, LLC
• Inventors: Harmon, Kent M., Wang, Kon-King M.
• Granted Patent: US 7,557,464 B2
• Time in Patent Office: Days
• US Class Current: 363/109
• CPC Class Codes: H02M 1/10 Arrangements incorporating converting means for enabling loads to be operated at will from different kinds of power supplies, e.g. from ac or dc

Abstract

A system and method for isolating sources and loads of a power system are disclosed. Briefly described, one embodiment includes at least a DC bus operable at a DC bus voltage; a non-isolated first primary converter module electrically coupled to the DC bus and operable to receive a first amount of power from a first power source, and operable to convert the received power from the first power source into a first amount of DC power at the DC bus voltage; and an isolated second primary converter module electrically coupled to the DC bus and operable to receive a second amount of power from a second power source, and operable to convert the received power from the second power source into a second amount of DC power at the DC bus voltage, wherein the second power source is electrically isolated from the DC bus by the isolated second primary converter module.

Claims

1. An input power control (IPC) module for transferring power from a plurality of power sources to an alternating current (AC) system, comprising:

a direct current (DC) bus operable at a DC bus voltage;

a non-isolated first primary converter module electrically coupled to the DC bus and operable to receive a first amount of power from a first power source, and operable to convert the received power from the first power source into a first amount of DC power at the DC bus voltage; and

an isolated second primary converter module electrically coupled to the DC bus and operable to receive a second amount of power from a second power source, and operable to convert the received power from the second power source into a second amount of DC power at the DC bus voltage,

wherein the second power source is electrically isolated from the DC bus by the isolated second primary converter module.

2. The IPC module of claim 1 wherein the first power source is not electrically isolated from the DC bus, wherein the first power source is electrically isolated from the AC system, and wherein the first power source is electrically isolated from the second power source.

3. The IPC module of claim 1, further comprising:

an isolation means electrically coupled between the isolated second primary converter module and the DC bus.

4. The IPC module of claim 1, further comprising:

an isolation means electrically coupled between the second power source and the isolated second primary converter module.

5. The IPC module of claim 1 wherein the isolated second primary converter module comprises:

a diode rectifier operable to convert the second amount of power into the second amount of DC power at a second DC voltage; and

an isolated DC/DC converter electrically coupled between the diode rectifier and the DC bus, operable to convert the second amount of power at the second DC voltage to the DC bus voltage, wherein the second power source is electrically isolated from the DC bus by the isolated DC/DC converter.

6. The IPC module of claim 5, further comprising:

a third primary converter module electrically coupled to the isolated DC/DC converter,

wherein the third primary converter module is operable to receive DC power from a DC power source at a third DC voltage, wherein the isolated DC/DC converter converts the received DC power into a third amount of DC power at the DC bus voltage, and wherein the DC power source is electrically isolated from the DC bus by the isolated DC/DC converter.

7. The IPC module of claim 6 where in response to the third primary converter module receiving power from the DC power source, the isolated second primary converter module is inoperable to receive the second amount of power.

8. The IPC module of claim 6 where in response to the isolated second primary converter module receiving power from the second power source, the third primary converter module is inoperable.

9. The IPC module of claim 1 wherein the isolated second primary converter module is an isolated AC/DC converter.

10. The IPC module of claim 1 wherein the isolated secondary primary converter is an isolated DC/DC converter.

11. The IPC module of claim 1, further comprising:

an isolated secondary converter module coupled to the DC bus, operable to receive the first amount of DC power and the second amount of DC power from the DC bus, operable to convert the received first amount and the received second amount of DC power to a first amount of AC power, and operable to transfer the first amount of AC power to the AC system,

wherein the isolated secondary converter module electrically isolates the AC system from the DC bus.

12. The IPC module of claim 11 wherein the isolated secondary converter module is an isolated DC/AC converter.

13. The IPC module of claim 11 wherein the isolated secondary converter module comprises:

a secondary isolation means that electrically isolates the AC system from the DC bus.

14. The IPC module of claim 13, wherein the secondary isolation means comprises:

an isolation transformer coupled between the AC system and the isolated secondary converter module, wherein the isolation transformer is operable to convert a first AC voltage provided from the isolated secondary converter module into a nominal AC voltage used by the AC system.

15. The IPC module of claim 1, further comprising:

an isolated third primary converter module coupled to the DC bus and operable to receive power from a third power source, and operable to convert the received power from the third power source into a third amount of DC power at the DC bus voltage,

wherein the third power source is electrically isolated from the DC bus by the isolated third primary converter module.

16. The IPC module of claim 15 wherein the isolated third primary converter module comprises:

an isolated DC/DC converter electrically coupled to the third power source, and wherein the isolated DC/DC converter is operable to receive DC power from the third power source at a DC voltage, wherein the isolated DC/DC converter converts the received DC power into the third amount of DC power at the DC bus voltage, and wherein the third power source is electrically isolated from the DC bus by the isolated DC/DC converter.

17. The IPC module of claim 15 wherein the isolated third primary converter module comprises:

a diode rectifier operable to convert the third amount of power into the third amount of DC power at a DC voltage; and

an isolated DC/DC converter electrically coupled between the diode rectifier and the DC bus, operable to convert the third amount of DC power at the DC voltage to the DC bus voltage, wherein the third power source is electrically isolated from the DC bus by the isolated DC/DC converter.

18. An input power control (IPC) module for transferring power from a plurality of power sources to an alternating current (AC) system, comprising:

a direct current (DC) bus operable at a DC bus voltage; and

at least two primary converter modules coupled to the DC bus and operable to receive power from the plurality of power sources, and operable to convert the received power into DC power at the DC bus voltage,

wherein a first one of the plurality of primary converter modules does not electrically isolate its respective power source from the DC bus, and wherein the remaining primary converter modules electrically isolate their respective power sources from the DC bus.

19. The IPC module of claim 18 further comprising a secondary converter coupled to the DC bus and operable to transfer power from the DC bus to the AC system, wherein the secondary converter electrically isolates the AC system from the DC bus.

20. The IPC module of claim 18, the remaining primary converter modules each comprising:

an isolation means coupled between their respective power source and the DC bus.

21. The IPC module of claim 20, wherein at least one of the isolation means comprises:

an isolated DC/DC converter, and wherein the respective power source is a DC power source.

22. The IPC module of claim 20, wherein at least one of the isolation means comprises:

an isolated DC/DC converter; and

a diode rectifier electrically coupled between the isolated DC/DC converter and the respective power source, and wherein the respective power source is an AC power source.

23. A method of transferring power from a plurality of power sources to an alternating current (AC) power system through an input power control (IPC) module, comprising:

converting a first amount of power, received from a first power source through a first primary converter module coupled to a direct current (DC) bus, into a first amount of DC power;

converting a second amount of power, received from a second power source through a second primary converter module coupled to the DC bus, into a second amount of DC power;

converting the first and the second amounts of DC power into AC power;

transferring the AC power to the AC power system through a secondary converter module coupled to the DC bus;

electrically isolating the second primary converter module from the DC bus; and

electrically isolating the secondary converter module from the DC bus.

24. The method of claim 23, wherein the first power source and the second power source are external to the IPC module.

25. An isolation system for electrically isolating a ground of a first power source, a ground of a second power source and a ground of an alternating current (AC) power system, comprising:

a first input power control (IPC) module, comprising;

a first primary converter that converts power received from the first power source into direct current (DC) power;

a first ground connection electrically coupled to a ground connection from the first power source, and that commonly grounds the first power source and the first IPC module; and

a first secondary converter electrically coupled to the first primary converter that converts the DC power received from the first primary converter into a first amount of AC power, and that transfers the first amount of AC power to the AC power system; and

a second IPC module, comprising;

a second primary converter that converts power received from the second power source into DC power;

a second ground connection electrically coupled to a ground connection from the second power source, and that commonly grounds the second power source and the second IPC module; and

a second secondary converter electrically coupled to the second primary converter and that converts the DC power received from the second primary converter into a second amount of AC power, and that transfers the second amount of AC power to the AC power system, wherein the ground connections of the commonly grounded first power source and first IPC module are electrically isolated from the ground connections of the commonly grounded second power source and second IPC module.

26. The isolation system of claim 25 wherein the first primary converter and the first secondary converter electrically isolate the first ground connection from the second IPC module, and wherein the second primary converter and the second secondary converter electrically isolate the second ground connection from the first IPC module.

27. The isolation system of claim 25 wherein the first primary converter and the first secondary converter electrically isolate the first ground connection from the AC power system.

28. The isolation system of claim 25 wherein the second primary converter and the second secondary converter electrically isolate the second ground connection from the AC power system.

29. The isolation system of claim 25 wherein the first power source is an AC power source and the ground connection from the AC power source is a ground potential voltage connection.

30. The isolation system of claim 25 wherein the first power source is an AC power source and the ground connection from the AC power source is a neutral potential voltage connection.

31. The isolation system of claim 25 wherein the first power source is a DC power source and the ground connection from the DC power source is a negative DC voltage connection.