Hybrid power source

• US 8,193,761 B1
• Filed: 11/08/2007
• Issued: 06/05/2012
• Est. Priority Date: 11/08/2007
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Singh, Harmohan N.
• Primary Examiner(s): DIAO, M BAYE
• Application Number:
  US11/937,341
• Publication Number:
  US 20120126619A1
• Time in Patent Office: 1,671 Days
• Field of Search: 320/104
• US Class Current: 320/104
• CPC Class Codes: B60L 2200/42 Fork lift trucks
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 50/40 using propulsion power supplied by capacitors
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: B60L 58/18 of two or more battery modules
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: B60L 58/40 for controlling a combination of batteries and fuel cells
• CPC Class Codes: H02J 2300/30 The power source being a fuel cell
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y02T 10/92 Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles
• CPC Class Codes: Y02T 90/40 Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

A hybrid power system is comprised of a high energy density element such as a fuel-cell and high power density elements such as a supercapacitor banks. A DC/DC converter electrically connected to the fuel cell and converting the energy level of the energy supplied by the fuel cell. A first switch is electrically connected to the DC/DC converter. First and second supercapacitors are electrically connected to the first switch and a second switch. A controller is connected to the first switch and the second switch, monitoring charge levels of the supercapacitors and controls the switching in response to the charge levels. A load is electrically connected to the second switch. The first switch connects the DC/DC converter to the first supercapacitor when the second switch connects the second supercapacitor to the load. The first switch connects the DC/DC converter to the second supercapacitor when the second switch connects the first supercapacitor to the load.

Claims

1. A method of operating a hybrid power system comprising:

charging a first capacitance bank;

connecting said first charged capacitance bank to a load;

charging a second capacitance bank;

connecting said second charged capacitance bank to the load;

disconnecting said first capacitance bank from said load;

connecting said first capacitance bank to an energy source while the second capacitance bank is connected to the load;

connecting said first capacitance bank to said load;

disconnecting said second capacitance bank from said load and connecting said second capacitance bank to an energy source while the first capacitance bank is connected to the load.

2. The method of claim 1 further comprising converting energy from said energy source prior to connection to the first capacitance bank and the second capacitance bank.

3. The method of claim 1, further comprising monitoring the charge of either the first or the second capacitance bank and sending a control signal to connect the charge monitored capacitance bank to said load when said charge reaches a predetermined level.

4. The method of claim 1, further comprising monitoring an output voltage level of either the first or second capacitance bank and sending a control signal to connect the voltage-level monitored capacitance bank to said load when said voltage level reaches a predetermined level.

5. A hybrid power system comprising:

a fuel cell;

a DC/DC converter electrically connected to said fuel cell and converting the energy level of the energy supplied by the fuel cell;

a first switch electrically connected to the DC/DC converter;

a first supercapacitor electrically connected to the first switch;

a second supercapacitor electrically connected to the first switch;

a second switch electrically connected to the first supercapacitor and to the second supercapacitor;

a controller connected to said first switch and said second switch, monitoring charge levels of said first supercapacitor and said second supercapacitor and controlling said first switch and said second switch in response to said charge levels;

a load electrically connected to the second switch;

wherein said first switch connects the DC/DC converter to the first supercapacitor when the second switch connects the second supercapacitor to the load and wherein said first switch connects the DC/DC converter to the second supercapacitor when the second switch connects the first supercapacitor to the load.

6. The hybrid power system of claim 5 wherein said load is an electrical vehicle traction motor.

7. The hybrid power system of claim 5 wherein said load is a robotic device electromechanical control.

8. The hybrid power system of claim 5 wherein said load comprises a load battery.