DC to DC converter and power management system

• US 6,882,063 B2
• Filed: 05/27/2003
• Issued: 04/19/2005
• Est. Priority Date: 07/28/2000
• Status: Active Grant

• Current Assignee: International Power Systems, Inc
• Original Assignee: International Power Systems, Inc
• Inventors: Hammerstrom, Donald J., Droppo, Gerald W., Schienbein, Lawrence A., Harris, Brent Earle
• Primary Examiner(s): DeBeradinis, Robert L.
• Application Number:
  US10/447,168
• Publication Number:
  US 20030201674A1
• Time in Patent Office: 693 Days
• Field of Search: 307/82, 307/65, 307/66
• US Class Current: 307/82
• CPC Class Codes: H02J 7/34 Parallel operation in networks using both storage and other dc sources, e.g. providing buffering H02J7/14 takes precedence
• CPC Class Codes: H02M 1/34 Snubber circuits
• CPC Class Codes: H02M 1/342 Active non-dissipative snubbers
• CPC Class Codes: H02M 3/155 using semiconductor devices only
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• CPC Class Codes: Y02B 40/00 Technologies aiming at improving the efficiency of home appliances, e.g. induction cooking or efficient technologies for refrigerators, freezers or dish washers
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A DC to DC Converter includes an electrical circuit that allows batteries and other electrical energy storage devices to be charged from or to discharge to a variable voltage DC bus. This electrical circuit also enables seamless integration with other energy storage devices and/or DC power sources, such as fuel cells, to provide DC power for a Power Management System. A Power Management System preferably provides both full power source management and power conditioning. The Power Management System is able to manage power flow to and from multiple, isolated power sources and energy storage devices to deliver high quality alternating current (“AC”) power to a load.

Claims

1. A power management system, comprising:

a plurality of independent DC power sources connected to a DC bus;

wherein at least one of the independent power sources comprises a rechargeable DC power source for supplying power to and receiving power from the DC bus, and wherein at least one of the DC power sources is a fuel cell or a PhotoVoltaic (PV) array;

a DC to DC converter connected between an output of the rechargeable DC power sources and the DC bus in parallel with the fuel cell or the PV array; and

a system controller for managing power transfer between the multiple independent DC power sources and the DC bus.

2. A power management system according to claim 1, wherein the system controller is configured to control the current supplied from each of the power sources to the DC bus and from the DC bus to each of the power sources.

3. A power management system according to claim 1, further comprising an inverter for converting DC power from the independent DC power sources into AC power.

4. A power management system according to claim 1, wherein the fuel cell comprises a fuel cell controller.

5. A power management system according to claim 4, wherein the system controller communicates with the fuel cell controller to control the amount of power supplied by the fuel cell to the DC bus.

6. A power management system according to claim 1, wherein the DC to DC converter further comprises a converter control circuit that communicates with the system controller to control an amount of power transferred between the DC to DC converter and the DC bus.

7. A power management system according to claim 1, further comprising an inverter, wherein the DC to DC converter is arranged in series between the fuel cell or the PV array and the inverter.

8. A power management system according to claim 1, further comprising an inverter, wherein the DC to DC converter is arranged in parallel with the fuel cell or the PV array and the inverter.

9. A method for managing multiple independent DC power sources, comprising:

arranging a plurality of independent DC power sources in communication with a DC bus;

wherein at least one of the DC power sources comprises a fuel cell or a PV array;

converting a voltage from one or more of the independent DC power sources to conform to a voltage of the DC bus;

wherein converting a voltage from one or more of the independent DC power sources to confirm to a voltage of the DC bus comprises arranging a DC to DC converter in series between one or more of the independent DC power sources and the DC bus and in parallel with the fuel cell or the PV array and the DC bus; and

controlling the amount of power that the DC bus supplies to or receives from one or more of the independent power sources.

10. A method of managing multiple independent DC power sources according to claim 9, wherein controlling the amount of power that the DC bus supplies to or receives from one or more of the independent power sources comprises integrating between a plurality of modes wherein each of the DC power sources is either supplying some or all of the required power, being recharged by one or more of the other DC power sources, or being isolated from the DC bus.

11. A method of managing multiple independent DC power sources according to claim 9, wherein converting a voltage from one or more of the independent DC power sources to conform to a voltage of the DC bus comprises arranging a DC to DC converter in series between a rechargeable DC power source and the DC bus.

12. A method of managing multiple independent DC power sources according to claim 11, wherein the DC to DC converter is arranged in parallel with the fuel cell or the PV array and an inverter.