Method and system of hybrid power management

• US 7,839,018 B2
• Filed: 07/29/2008
• Issued: 11/23/2010
• Est. Priority Date: 04/22/2008
• Status: Expired due to Fees

• Current Assignee: Institute Of Nuclear Energy Research Atomic Energy Council Executive Yuan
• Original Assignee: Institute Of Nuclear Energy Research Atomic Energy Council Executive Yuan
• Inventors: Huang, Chih-Lin, Chang, Chi-Yuan, Lin, Yeong-Der, Lin, Wei-Wei, Chen, Charn-Ying
• Primary Examiner(s): Kaplan; Hal I
• Application Number:
  US12/181,456
• Publication Number:
  US 20090261657A1
• Time in Patent Office: 847 Days
• Field of Search: 307/44, 307/45, 307/46, 307/48, 307/80
• US Class Current: 307/46
• CPC Class Codes: H01M 16/006 of fuel cells with rechargeable batteries
• CPC Class Codes: H01M 8/04537 Electric variables
• CPC Class Codes: H01M 8/04559 of fuel cell stacks
• CPC Class Codes: H01M 8/04567 of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H01M 8/04589 of fuel cell stacks
• CPC Class Codes: H01M 8/04597 of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H01M 8/0494 of fuel cell stacks
• CPC Class Codes: H01M 8/04947 of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H01M 8/04955 Shut-off or shut-down of fuel cells
• CPC Class Codes: H02J 2300/30 The power source being a fuel cell
• 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: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A method of hybrid power management is provided in the present invention, comprising steps of: providing a hybrid power output device being coupled to a load and comprising a fuel cell module and a secondary cell module; determining a plurality of threshold values, each representing one of output power modes of the hybrid power output device respectively; and monitoring a characteristic value output from the fuel cell module and comparing the characteristic value with the threshold values to determine one of the output power modes to supply power to the load. Moreover, the present invention further provides a system of hybrid power management using the foregoing method to control switches to select from the output power modes such as supplying power from the fuel cell module only, from both the fuel cell module and the secondary battery, or cutting off power supply to the load according to the power state of the fuel cell module.

Claims

1. A method of hybrid power management, comprising steps of

providing a hybrid power output device being coupled to a load and comprising a fuel cell module and a secondary cell module;

determining a plurality of threshold values, each representing one of a plurality of output power modes of the hybrid power output device respectively; and

monitoring a characteristic value output from the fuel cell module and comparing the characteristic value with the threshold values to determine one of the output power modes to supply power to the load.

2. The method of hybrid power management as recited in claim 1, wherein the plurality of threshold values comprise a first threshold value representing the output power mode that the fuel cell module supplies power to the load, a second threshold value representing the output power mode that the fuel cell module and the secondary cell module supply power to the load, and a third threshold value representing the output power mode that power to the load from the hybrid power output device is cut off.

3. The method of hybrid power management as recited in claim 1, wherein the plurality of threshold values comprise a first threshold value representing the output power mode that the fuel cell module supplies power to the load, a second threshold value representing one selected from the output power mode that the fuel cell module supplies power to the load and the output power mode that the fuel cell module and the secondary cell module supply power to the load according to the trend of the characteristic value, a third threshold value representing one selected from the output power mode that the fuel cell module and the secondary cell module supply power to the load and the output power mode that power to the load from the hybrid power output device is cut off, and a fourth threshold value representing the output power mode that power to the load from the hybrid power output device is cut off.

4. The method of hybrid power management as recited in claim 3, wherein the trend of the characteristic value is dropping from the first threshold value to the second and the third threshold values or rising from the fourth threshold value to the second and the third threshold values.

5. The method of hybrid power management as recited in claim 1, further comprising a step wherein the fuel cell module charges the secondary cell module.

6. A system of hybrid power management, comprising:

a hybrid power output device comprising a fuel cell module and a secondary cell module being electrically coupled to the fuel cell module through a first switch;

a load being electrically coupled to the hybrid power output device through a second switch;

a sensor unit being capable of monitoring a characteristic value output from the fuel cell module to generate a sensor signal; and

a control unit being capable of determining a plurality of threshold values, each representing one of a plurality of output power modes of the hybrid power output device respectively and being capable of receiving the sensor signal and comparing the sensor signal with the threshold values to control the first switch or the second switch to determine one of the output power modes to supply power to the load.

7. The system of hybrid power management as recited in claim 6, wherein the plurality of threshold values comprise a first threshold value representing the output power mode that the first switch is off and the second switch is on, a second threshold value representing the output power mode that the first switch and the second switch are both on, and a third threshold value representing the output power mode that the second switch is off.

8. The system of hybrid power management as recited in claim 6, wherein the plurality of threshold values comprise a first threshold value representing the output power mode that the first switch is off and the second switch is on, a second threshold value representing one selected from the output power mode that the first switch and the second switch are both on and the output power mode that the first switch is off and the second switch is on according to the trend of the sensor signal, a third threshold value representing one selected from the output power mode that the fuel cell module and the secondary cell module supply power to the load and the output power mode that power to the load from the hybrid power output device is cut off, and a fourth threshold value representing the output power mode that the second switch is off.

9. The system of hybrid power management as recited in claim 8, wherein the trend of the sensor signal is dropping from the first threshold value to the second and the third threshold values or rising from the fourth threshold value to the second and the third threshold values.

10. The system of hybrid power management as recited in claim 6, further comprising a DC/DC converter disposed between the fuel cell module and the secondary cell module.

11. The system of hybrid power management as recited in claim 6, further comprising a DC/DC converter disposed between the hybrid power output device and the load.

12. The system of hybrid power management as recited in claim 6, further comprising a DC/DC converter disposed between the fuel cell module and first switch.