Control system for a renewable energy system

• US 6,674,263 B2
• Filed: 06/05/2002
• Issued: 01/06/2004
• Est. Priority Date: 06/05/2002
• Status: Expired due to Fees

• Current Assignee: Kodjo Agbossou, Rémy Simard, Sousso Kelouwani, Tapan K. Bose
• Original Assignee: Kodjo Agbossou, Rémy Simard, Sousso Kelouwani, Tapan K. Bose
• Inventors: Kelouwani, Sousso, Bose, Tapan K., Agbossou, Kodjo, Simard, Rémy
• Primary Examiner(s): Tibbits, Pia
• Application Number:
  US10/162,208
• Publication Number:
  US 20030227276A1
• Time in Patent Office: 580 Days
• Field of Search: 320/101, 307/66, 307/43, 307/44, 307/151, 307/153, 307/64, 323/207, 323/234, 323/282, 323/284, 429/7, 429/12, 429/13, 429/17, 429/90, 701/27
• US Class Current: 320/101
• CPC Class Codes: H01M 16/006 of fuel cells with rechargeable batteries
• CPC Class Codes: H01M 8/04201 Reactant storage and supply, e.g. means for feeding, pipes
• CPC Class Codes: H01M 8/04992 characterised by the implementation of mathematical or computational algorithms, e.g. feedback control loops, fuzzy logic, neural networks or artificial intelligence
• CPC Class Codes: H01M 8/0656 by electrochemical means H01M8/065 takes precedence
• CPC Class Codes: H02J 2300/30 The power source being a fuel cell
• CPC Class Codes: H02J 3/28 Arrangements for balancing of the load in a network by storage of energy
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/36 Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02E 70/30 Systems combining energy storage with energy generation of non-fossil origin

Abstract

A renewable energy (RE) system is disclosed which comprises an energy source providing unit, a DC bus, a buck converter, an hydrogen generator, an hydrogen storage, an energy conversion device, a boost converter, a DC to AC converter, and a monitoring system.

Claims

1. An energy stand-alone supply providing electrical power to a load having an electrical power need using an energy supply source providing a source electrical power, wherein a time-variable discrepancy between said source electrical power provided by said energy supply source and said electrical power need, the energy stand-alone supply maintaining the provided electrical power between two pre-determined, the energy stand-alone supply comprising:

a buffer receiving a source electrical power from an energy supply, the buffer further providing electrical power to a load according to an electrical power need of said load;

a first power converter connected to said buffer and providing a converted electrical power using at least one part of the source electrical power in response to a first control signal;

a hydrogen generator receiving said converted electrical power and generating hydrogen using said provided converted electrical power;

a hydrogen storage storing the generated hydrogen provided by said hydrogen generator;

a hydrogen conversion device receiving at least one part of said hydrogen of said hydrogen storage and providing a generated electrical power in response to a second control signal;

a second converter receiving said generated electrical power and providing a converted electrical power of the generated electrical power to said buffer;

a control unit providing said first and second signal, the control unit enabling the maintaining of the provided electrical power between the two pre-determined according to a control scheme.

2. The apparatus as claimed in claim 1, wherein the buffer is a battery.

3. The apparatus as claimed in claim 1, wherein the buffer is a capacitor.

4. The apparatus as claimed in claim 1, wherein the hydrogen conversion device is an ICE coupled with a co-generator.

5. The apparatus as claimed in claim 1, wherein the buffer is a DC bus.

6. The apparatus as claimed in claim 1, wherein the energy supply source comprises a wind turbine.

7. The apparatus as claimed in claim 1, wherein the energy supply source comprises at least one photovoltaic array.

8. The apparatus as claimed in claim 1, further comprising a memory and an addressing unit, the memory comprising at least more than one pulse width modulation signals in order to drive the first controller.

9. The apparatus as claimed in claim 8, wherein the addressing unit comprises a binary counter and an interface to select at least one of said more than one pulse width modulation signals.

10. The apparatus as claimed in claim 1, further comprising the control unit providing the first and the second control signals, the control unit comprising at least one sensor for sensing the electrical power of said buffer and the electrical power need of the load.

11. The apparatus as claimed in claim 1, further comprising a first control unit providing the first control signal, the first control unit comprising sensors for sensing the electrical power of said buffer and the electrical power need of the load;

the apparatus further comprising a second control unit providing the second control signal, the second control unit comprising sensors for sensing the electrical power of said buffer and the electrical power need of the load.

12. The apparatus as claimed in claim 11, wherein the first and the second control unit comprises a micro-controller.

13. The apparatus as claimed in claim 11, wherein the first and the second control unit comprises a digital signal processor (DSP).

14. The apparatus as claimed in claim 11, wherein each control unit is implemented using a hysteresis scheme.

15. The apparatus as claimed in claim 11, wherein each control unit is implemented using a fuzzy-logic scheme.

16. The apparatus as claimed in claim 11, wherein each control unit is implemented using a PI-type or PID-type controller.

17. The apparatus as claimed in claim 1, further comprising a remote control connected to said control unit.

20. The apparatus as claimed in claim 1, wherein the energy supply source is an energy surplus generated by a power plant.

18. A method for providing electrical power to a load having an electrical power need using an energy supply and maintaining the provided electrical power between two pre-determined values, wherein a time-variable discrepancy exists between said electrical power provided by said energy supply and said electrical power need of the load, the method comprising the steps of:

measuring an electrical power need of a load and an available electrical power of an energy supply;

comparing said electrical power need of the load to said available electrical power of the energy supply to provide a comparison value;

if said comparison value is larger than a first predetermined value, operating a hydrogen conversion device to, provide extra electrical power using hydrogen stored in a hydrogen storage, thereby increasing the available electrical power, the operation being performed until said available electrical power reaches the electrical power need of the load;

if said electrical power need of the load is lower with respect to said available electrical power of the energy supply by a second predetermined value, switching on a hydrogen generator, that provides hydrogen to the hydrogen storage, thereby decreasing the available electrical power, the switching on being performed until said available electrical power reaches the electrical power need of the load.

19. The method as claimed in claim 18, further comprising the step of modifying the two predetermined values.

21. The method as claimed in claim 18, wherein said energy supply is an energy surplus provided by a power plant.