Topologies for multiple energy sources

1. A system comprising:

a first direct current (DC) power source having a first-source positive DC terminal and a first-source negative DC terminal;

a second DC power source having a second-source positive DC terminal and a second-source negative DC terminal;

an output capacitor having an output-capacitor positive terminal operably coupled with the second-source positive DC terminal and an output-capacitor negative terminal operably coupled with the first-source negative DC terminal;

a series electrical connection between the first-source positive DC terminal and the second-source negative DC terminal;

a boost converter having a boost-converter DC input operably coupled with the series electrical connection and the first-source negative DC terminal, and a boost-converter DC output operably coupled with the output-capacitor positive and negative terminals; and

a buck-boost converter having a buck-boost-converter DC input operably coupled with the series electrical connection and the second-source positive DC terminal, and a buck-boost-converter DC output operably coupled with the output-capacitor positive and negative terminals.

2. The system of claim 1 wherein the boost converter and the buck-boost converter share an inductor electrically connected with the series electrical connection.

3. The system of claim 1 wherein the boost converter having the boost-converter DC input operably coupled with the series electrical connection and the first-source negative DC terminal, and the boost-converter DC output operably coupled with the output-capacitor positive and negative terminals comprises:

a first diode having a first-diode anode (+) and a first-diode cathode (−), the first-diode cathode (−) operably coupled with the output-capacitor positive terminal;

a first switch operably coupled between the first-diode anode (+) and the first-source negative DC terminal; and

an inductor operably coupled between the series electrical connection and the first-diode anode (+).

4. The system of claim 1 wherein the buck-boost converter having the buck-boost converter DC input operably coupled with the series electrical connection and the second-source positive DC terminal, and the buck-boost converter DC output operably coupled with the output-capacitor positive and negative terminals comprises:

a first diode having a first-diode anode (+) and a first-diode cathode (−), the first-diode anode (+) operably coupled with the output-capacitor negative terminal;

a first switch operably coupled between the first diode cathode (−) and the second-source positive DC terminal; and

an inductor operably coupled between the series electrical connection and the first-diode cathode (−).

5. The system of claim 1 , further comprising:

a switch of the buck-boost converter operably coupled with a diode of the boost converter such that the diode of the boost converter is not forward biased when the switch of the buck-boost converter is transferring current.

6. The system of claim 1 , further comprising:

a switch of the boost converter operably coupled with a diode of the buck-boost converter such that the diode of the buck-boost converter is not forward biased when the switch of the boost converter is transferring current.

7. The system of claim 1 , further comprising:

an energy storage component connected in electrical parallel with the first DC power source.

8. The system of claim 7 , further comprising:

a bi-directional dc—dc converter having an input operably coupled with the first DC power source and an output operably coupled with the energy storage component.

9. The system of claim 1 , further comprising:

an energy storage component connected in electrical parallel with the second DC power source.

10. The system of claim 9 , further comprising:

a bi-directional dc—dc converter having an input operably coupled with the second DC power source and an output operably coupled with the energy storage component.

11. The system of claim 1 , further comprising:

a 3-phase inverter operably coupled with the output capacitor.

12. The system of claim 1 wherein the first DC power source comprises:

at least one of a fuel cell, a battery, an electrolytic capacitor, and an ultra capacitor.

13. The system of claim 1 wherein the second DC power source comprises:

at least one of a fuel cell, a battery, an electrolytic capacitor, and an ultra capacitor.

14. An electrical power supply to supply electrical power between a first power source, a second power source, and a load, wherein the first power source is in serial connection with the second power source the electrical power supply comprising:

a boost converter coupled between the first power source and the load; and

a buck-boost converter coupled between the second power source and the load, wherein the buck-boost converter is operable to provide power from the second power source to the load at a first time, and the boost converter is operable to provide power from the first power source to the load at a second time,

wherein the buck-boost converter is further operable to provide power from the load to the second power source at a third time.

15. The electrical power supply of claim 14 wherein the second power source is rechargeable.

16. An electrical power supply to supply electrical power between a first power source, a second power source, and a load, wherein the first power source is in serial connection with the second power source, the electrical power supply comprising:

a boost converter coupled between the first power source and the load; and

a buck-boost converter coupled between the second power source and the load, wherein the buck-boost converter is operable to provide power from the second power source to the load at a first time, and the boost converter is operable to provide power from the first power source to the load at a second time; and

an inverter electrically coupled between the load and the boost and the buck-boost converters.

17. The electrical power supply of claim 16 wherein the second power source is rechargeable.

18. A system for use with a first direct current (DC) power source and a second DC power source, the system comprising:

a boost converter having a boost-converter-input positive DC terminal and a boost-converter-input negative DC terminal and boost-converter-output DC terminals operably coupled with an output capacitor having output-capacitor positive and negative terminals;

a buck-boost converter having a buck-boost-converter-input positive DC terminal and a buck-boost-converter-input negative DC terminal and buck-boost-converter-output DC terminals operably coupled with the output-capacitor positive and negative terminals; and

a series electrical connection between the boost-converter-input positive DC terminal and the buck-boost-converter-input negative DC terminal.

19. The system of claim 18 wherein the boost converter and the buck-boost converter share an inductor electrically connected with the series electrical connection.

20. The system of claim 18 , further comprising:

a 3-phase inverter operably coupled with the output capacitor.

21. The system of claim 20 , further comprising:

a 3-phase load operably coupled with the 3-phase inverter.

22. The system of claim 18 wherein the first DC power source comprises:

at least one of a fuel cell, a battery, an electrolytic capacitor, and an ultra capacitor operably coupled with the buck-boost converter.

23. The system of claim 18 wherein the second DC power source comprises:

at least one of a fuel cell, a battery, an electrolytic capacitor, and an ultra capacitor operably coupled with the buck-boost converter.

24. A method for use with an electrical power supply, the method comprising:

coupling a first-power-source negative DC terminal with an output-capacitor negative DC terminal;

coupling a first-power-source positive DC terminal with a second-power-source negative terminal;

coupling a second-power-source positive DC terminal with an output-capacitor positive terminal;

coupling a buck-boost converter DC input with the second-power-source negative DC terminal and the second-power-source positive DC terminal;

coupling a buck-boost converter DC output with the output-capacitor positive and negative terminals;

coupling a boost converter DC input with the first-power-source positive DC terminal and the first-power-source negative DC terminal; and

coupling a boost converter DC output with the output-capacitor positive and negative terminals.

25. The method of claim 24 , further comprising:

coupling a 3-phase inverter with the output capacitor positive and negative terminals.

26. The method of claim 25 , further comprising:

coupling a 3-phase load with the 3-phase inverter.

27. A system comprising:

a first power source node having a first-node positive terminal and a first-node negative terminal;

a second power source node having a second-node positive terminal and a second-node negative terminal;

an output capacitor having an output-capacitor positive terminal operably coupled with the second-node positive terminal and an output-capacitor negative terminal operably coupled with the first-node negative terminal;

a series electrical connection between the first-node positive terminal and the second-node negative terminal; and

an inductor electrically connected to the series electrical connection, the inductor forming a part of a boost converter and the inductor forming a part of a buck-boost converter.

28. The system of claim 27 wherein the inductor electrically connected to the series electrical connection, the inductor forming a part of a boost converter and the inductor forming a part of a buck-boost converter further comprises:

a boost-converter diode and a boost-converter switch electrically connected with the inductor;

a buck-boost-converter diode and a buck-boost-converter switch electrically connected with the inductor; and

the boost-converter switch connected in electrical parallel with the buck-boost-converter diode such that the buck-boost-converter diode is not forward biased when the boost-converter switch is transferring current.

29. The system of claim 27 , wherein the inductor electrically connected to the series electrical connection, the inductor forming a part of a boost converter and the inductor forming a part of a buck-boost converter comprises:

a boost-converter diode and a boost-converter switch electrically connected with the inductor;

a buck-boost-converter diode and a buck-boost-converter switch electrically connected with the inductor; and

the buck-boost-converter switch connected in electrical parallel with the boost-converter diode such that the boost-converter diode is not forward biased when the buck-boost-converter switch is transferring current.

30. The system of claim 27 , further comprising:

a 3-phase inverter operably coupled with the output capacitor.

31. The system of claim 27 wherein the first power source node comprises:

a connector configured for detachably connecting to at least one terminal of at least one of a fuel cell, a battery, an electrolytic capacitor, and an ultra capacitor.

32. The system of claim 27 wherein the second power source node comprises:

a connector configured for permanently connecting to at least one terminal of at least one of a fuel cell, a battery, an electrolytic capacitor, and an ultra capacitor.