Method for controlling an electric power plant associated with a temporally random power source

• US 6,489,743 B1
• Filed: 03/26/2001
• Issued: 12/03/2002
• Est. Priority Date: 07/03/1998
• Status: Expired due to Term

• Current Assignee: Electricitã© De France
• Original Assignee: Electricitã© De France
• Inventors: Alzieu, Jean, Smimite, Hassan, Camps, Jean-Claude
• Primary Examiner(s): Tso, Edward H.
• Assistant Examiner(s): TIBBITS, PIA FLORENCE
• Application Number:
  US09/743,203
• Time in Patent Office: 617 Days
• Field of Search: 320/101, 320/102
• US Class Current: 320/102
• CPC Class Codes: H02J 7/0024 Parallel/serial switching of connection of batteries to charge or load circuit
• CPC Class Codes: H02J 7/35 with light sensitive cells
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors

Abstract

The method serves for the control of an electric power plant (2) associated with a power source (6) with temporally random availability, the plant comprising at least one battery (10) adapted to be supplied with electric current from the source. When the random power (6) is available, the battery (10) current supply is controlled. The supply is controlled so as to come as close as possible to a state of complete charge of the battery, and preferably to reach this state.

Claims

1. Method for controlling an electric power plant associated with a power source with temporally random availability, the plant comprising at least one battery adapted to be supplied with electric current from the source, in which method, when the random power is available, the battery current supply is controlled, wherein the supply is controlled so as to come as close as possible to a state of complete charge of the battery, and preferably to reach this state.

2. Method according to claim 1, wherein, after the battery has been supplied so as to have received a quantity of electricity above a first predetermined threshold, the plant is controlled in such a way that delivery of current by the battery is disabled.

3. Method according to claim 2, wherein, after the battery has been supplied so as to have received a quantity of electricity below the first threshold and when a delivery of current is requested, the delivery of current by the battery is enabled.

4. Method according to claim 3, wherein, after the battery has delivered current so as to reach a state of partial nonzero charge, and when the random power is available, the plant is controlled in such a way that current supply to the battery is enabled until it has received a quantity of electricity equal to the first threshold.

5. Method according to claim 3, wherein, when the random power is available, the plant is controlled in such a way that, according to the following order of decreasing priorities:

when the or at least one of the batteries has received a quantity of electricity below the first threshold, the or successfully each of these batteries is supplied until it has received a quantity of electricity equal to the first threshold;

when the or at least one of the batteries has a state or partial charge above the second threshold, the or successively each of these batteries is supplied until it reaches a state of complete charge; and

when the or at least one of the batteries has received a quantity of electricity above the first threshold and has a state of partial charge below the second threshold, the or successively each of these batteries is supplied with current until it reaches a state of partial charge equal to the second threshold.

6. Method according to claim 3, wherein, when the random power is available, the plant is controlled in such a way that, according to the following order of decreasing priorities:

when the or at least one of the batteries has a state of partial charge above the second threshold, the or successively each of these batteries is supplied with current until it reaches a state of complete charge;

when the or at least one of the batteries has received a quantity of electricity below the first threshold, the or successively each of these batteries is supplied with current until it has received a quantity of electricity equal to the first threshold; and

when the or at least one of the batteries has received a quantity of electricity above the first threshold and has a state of partial charge below the second threshold, the or successively each of these batteries is supplied with current until it reaches a state of partial charge equal to the second threshold.

7. Method according to claim 3, wherein, when the random power is available, the plant is controlled in such a way that, according to the following order of decreasing priorities:

when the or at least one of the batteries has a state of partial charge above the second threshold, the or successively each of these batteries is supplied with current until it reaches a state of complete charge;

when the or at least one of the batteries has received a quantity of electricity above the first threshold and has a state of partial charge below the second threshold, the or successively each of these batteries is supplied with current until it reaches a state of partial charge equal to the second threshold; and

when the or at least one of the batteries has received a quantity of electricity below the first threshold, the or successively each of these batteries is supplied with current until it has received a quantity of electricity equal to the first threshold.

8. Method according to claim 1, wherein, the plant comprising at least two batteries, in particular which are adapted to be connected in parallel one with respect to the other, after the two batteries or at least two of the batteries have reached a state of partial charge below a second predetermined threshold and when the random power is available, the plant is controlled in such a way that a single first of these batteries is supplied first until it reaches a state of partial charge equal to the second threshold.

9. Method according to claim 8, wherein, after the first battery has reached the second threshold and when the random power is available, the plant is controlled in such a way that the first battery and the or another of the batteries having a state of partial charge below the second threshold are supplied simultaneously.

10. Method according to claim 1, wherein, the plant comprising at least two batteries, in particular which are adapted to be connected in parallel one with respect to the other, when the random power is available and a delivery of current by the plant is requested, the plant is controlled in such a way that current is delivered simultaneously from all the batteries which are not in the charging phase.

11. Method according to claim 1, wherein, after the or one of the batteries has reached a state of zero charge and then goes to the state of complete charge, a quantity of electricity which the battery receives so as to go from the state of zero charge to a state of charge equal to a second predetermined threshold is measured.

12. Method according to claim 11, wherein the plant is controlled so as to reach the state of zero charge of the battery.

13. Method according to claim 1, wherein the or at least one of the batteries comprising at least two subassemblies current, at least two voltages in series are measured on the battery, each comprising a voltage across the terminals of a respective one of the subassemblies.

14. Method according to claim 1, wherein the battery or batteries are furthermore adapted to be supplied with electric current from a power source with temporally definite availability.

15. Electric power plant adapted to be associated with a power source with temporally random availability, the plant comprising at least one battery adapted to be supplied with electric current from the source, and control means for controlling the plant, wherein the control means controls the battery current supply, when the random power is available, so as to come as close as possible to a state of complete charge of the battery, and preferably to reach this state.

16. Plant according to claim 15, wherein, the plant comprising at least two batteries, in particular which are adapted to be connected in parallel one with respect to the other, the plant comprises means for disabling the delivery of current by any one of the batteries to the other or to any other of the batteries.

17. Plant according to claim 15, wherein the plant comprises four batteries.

18. A method of operating an electric power plant associated with a power source with temporally random availability, the plant comprising at least one battery adapted to be supplied with electric current from the source, said method comprising:

determining an effective capacity of said at least one battery in a state of complete charge;

measuring quantity of electricity entering said at least one battery during a charging phase; and

controlling the electric current from the source to said at least one battery based on (1) the quantity of electricity entering the battery, and (2) the effective capacity of the battery.

19. The method according to claim 18, further comprising computing quantity of electricity which the at least one battery needs to receive in order to reach said state of complete charge.

20. The method according to claim 18, further comprising:

determining when the at least one battery has reached the state of complete charge based on the quantity of electricity entering the at least one battery and the effective capacity of the at least one battery; and

disconnecting the at least one battery from the source when the state of complete charge is determined.