Grid regulation services for energy storage devices based on grid frequency

• US 8,700,225 B2
• Filed: 04/10/2012
• Issued: 04/15/2014
• Est. Priority Date: 04/06/2010
• Status: Active Grant

• Current Assignee: Battelle Memorial Institute
• Original Assignee: Battelle Memorial Institute
• Inventors: Pratt, Richard M., Hammerstrom, Donald J., Kintner-Meyer, Michael C. W., Tuffner, Francis K.
• Primary Examiner(s): JARRETT, RYAN A
• Application Number:
  US13/443,620
• Publication Number:
  US 20120200160A1
• Time in Patent Office: 735 Days
• Field of Search: 700/295, 700/297, 700/298, 320/107, 320/109, 307/46, 307/48, 307/66
• US Class Current: 700/297
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/70 Interactions with external data bases, e.g. traffic centres
• CPC Class Codes: B60L 2240/80 Time limits
• CPC Class Codes: B60L 2250/12 by confirmation, e.g. of the input
• CPC Class Codes: B60L 2260/58 Departure time prediction
• CPC Class Codes: B60L 53/16 Connectors, e.g. plugs or sockets, specially adapted for charging electric vehicles
• CPC Class Codes: B60L 53/305 Communication interfaces
• CPC Class Codes: B60L 53/51 Photovoltaic means
• CPC Class Codes: B60L 53/53 Batteries
• CPC Class Codes: B60L 53/56 Mechanical storage means, e.g. fly wheels
• CPC Class Codes: B60L 53/63 in response to network capacity
• CPC Class Codes: B60L 53/65 involving identification of vehicles or their battery types
• CPC Class Codes: B60L 53/68 Off-site monitoring or control, e.g. remote control
• CPC Class Codes: B60L 55/00 Arrangements for supplying energy stored within a vehicle to a power network, i.e. vehicle-to-grid [V2G] arrangements
• CPC Class Codes: B60L 58/13 Maintaining the SoC within a determined range
• CPC Class Codes: G05B 13/02 electric
• CPC Class Codes: G05B 15/02 electric
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H02J 13/00 Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network
• CPC Class Codes: H02J 13/00006 : characterised by information or instructions transport means between the monitoring, controlling or managing units and monitored, controlled or operated power network element or electrical equipment
• CPC Class Codes: H02J 3/241 : The oscillation concerning frequency
• CPC Class Codes: H02J 3/322 : the battery being on-board an electric or hybrid vehicle, e.g. vehicle to grid arrangements [V2G], power aggregation, use of the battery for network load balancing, coordinated or cooperative battery charging
• 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: Y02B 90/20 : Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y02E 60/00 : Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 90/12 : Electric charging stations
• CPC Class Codes: Y02T 90/14 : Plug-in electric vehicles
• CPC Class Codes: Y02T 90/16 : Information or communication technologies improving the operation of electric vehicles
• CPC Class Codes: Y02T 90/167 : Systems integrating technologies related to power network operation and communication or information technologies for supporting the interoperability of electric or hybrid vehicles, i.e. smartgrids as interface for battery charging of electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: Y04S 10/126 : the energy generation units being or involving electric vehicles [EV] or hybrid vehicles [HEV], i.e. power aggregation of EV or HEV, vehicle to grid arrangements [V2G]
• CPC Class Codes: Y04S 10/14 : Energy storage units
• CPC Class Codes: Y04S 30/12 : Remote or cooperative charging
• CPC Class Codes: Y04S 30/14 : Details associated with the interoperability, e.g. vehicle recognition, authentication, identification or billing
• CPC Class Codes: Y04S 40/12 : characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment

Abstract

Disclosed herein are representative embodiments of methods, apparatus, and systems for charging and discharging an energy storage device connected to an electrical power distribution system. In one exemplary embodiment, a controller monitors electrical characteristics of an electrical power distribution system and provides an output to a bi-directional charger causing the charger to charge or discharge an energy storage device (e.g., a battery in a plug-in hybrid electric vehicle (PHEV)). The controller can help stabilize the electrical power distribution system by increasing the charging rate when there is excess power in the electrical power distribution system (e.g., when the frequency of an AC power grid exceeds an average value), or by discharging power from the energy storage device to stabilize the grid when there is a shortage of power in the electrical power distribution system (e.g., when the frequency of an AC power grid is below an average value).

Claims

1. A method, comprising:

monitoring a frequency of an electrical power distribution system;

when the frequency of the electrical power distribution system is in a first frequency range, receiving power from the electrical power distribution system and charging an energy storage device at a charging rate with the received power, the charging rate being selected based at least in part on a pre-determined or user-selected completion time for charging the energy storage device; and

when the frequency of the electrical power distribution system is in a second frequency range different from the first frequency range, discharging the energy storage device at a discharging rate and delivering power from the energy storage device to the electrical power distribution system, the discharging rate being selected based on a measured average charging rate for the energy storage device, the discharging rate also being selected to allow charging the energy storage device to a completion charge by the end of the pre-determined or user-selected completion time.

2. The method of claim 1, wherein the discharging rate is based at least in part on an average frequency derived from the frequency of the electrical power distribution system.

3. The method of claim 1, wherein the discharging rate is based on a state-of-charge of the energy storage device.

4. The method of claim 1, further comprising clamping the charging rate or the discharging rate below a first selected charging rate or above a second selected charging rate, wherein the first and second selected charging rates are selected in response to a pre-determined or user-selected completion time for charging the energy storage device.

5. One or more non-transitory computer-readable storage media storing computer-readable instructions that when executed by a computer cause the computer to perform a method, the method comprising:

monitoring a frequency of an electrical power distribution system;

when the frequency of the electrical power distribution system is in a first frequency range, receiving power from the electrical power distribution system and charging an energy storage device at a charging rate with the received power; and

when the frequency of the electrical power distribution system is in a second frequency range different from the first frequency range, discharging the energy storage device at a discharging rate clamped below a discharging rate selected in response to an actual average charging rate for the energy storage device and a completion time for charging the energy storage device and delivering power from the energy storage device to the electrical power distribution system.

6. The one or more non-transitory computer-readable storage media of claim 5, wherein the discharging rate is based at least in part on an average frequency derived from the frequency of the electrical power distribution system.

7. The one or more non-transitory computer-readable storage media of claim 5, wherein the discharging rate is based on a state-of-charge of the energy storage device.

8. The one or more non-transitory computer-readable storage media of claim 5, wherein the method further comprises clamping the charging rate below a selected charging rate, the selected charging rate being selected in response to a pre-determined or user-selected completion time for charging the energy storage device.

9. A system, comprising:

one or more processing units;

the one or more non-transitory computer-readable storage media of claim 5; and

an interface to a bi-directional charger operable to charge and discharge the energy storage device responsive to the processing units executing computer-readable instructions stored on the computer-readable storage media.

10. A method, comprising:

charging an energy storage device in response to a frequency of an electrical power distribution system when the frequency is within a first frequency range, the charging occurring responsive to a pre-determined or user-selected completion time for charging the energy storage device at a charging rate selected based at least in part on an actual average charging rate for an energy storage device;

discharging the energy storage device in response to a frequency of the electrical power distribution system when the frequency is within a second frequency range, the discharging occurring responsive to the pre-determined or user-selected completion time for charging the energy storage device; and

delivering power from the discharging energy storage device to the electrical power distribution system.

11. The method of claim 10, wherein the discharging occurs responsive at least in part to an average frequency derived from the frequency of the electrical power distribution system.

12. The method of claim 10, wherein the discharging occurs responsive to a state-of-charge of the energy storage device exceeding a predefined value.

13. The method of claim 10, wherein the frequency is a first frequency, further comprising:

charging an energy storage device in response to a second frequency of the electrical power distribution system when the second frequency is within a second frequency range; and

receiving power transmitted from the electrical power distribution system to the charging energy storage device.

14. The method of claim 13, further comprising a step for generating a regulation signal causing a charging system to perform the acts of charging the energy storage device and receiving the power.

15. The method of claim 10, wherein the frequency is an instantaneous frequency.

16. The method of claim 10, further comprising a step for generating a regulation signal causing a charging system to perform the acts of discharging the energy storage device and delivering the power.

17. One or more non-transitory computer-readable storage media storing computer-readable instructions that when executed by a computer cause the computer to perform a method, the method comprising:

charging an energy storage device in response to a frequency of an electrical power distribution system when the frequency is within a first frequency range at a charging rate selected based at least in part on an actual average charging rate for an energy storage device;

discharging an energy storage device in response to a frequency of an electrical power distribution system when the frequency is within a second frequency range, the discharging occurring responsive to the pre-determined or user-selected completion time for charging the energy storage device at a discharging rate selected based at least in part on an actual average charging rate for an energy storage device; and

delivering power from the discharging energy storage device to the electrical power distribution system.

18. The one or more non-transitory computer-readable storage media of claim 17, wherein the discharging occurs responsive to a state-of-charge of the energy storage device exceeding a predefined value.

19. The one or more non-transitory computer-readable storage media of claim 17, wherein the frequency is a first frequency, further comprising:

charging an energy storage device in response to a second frequency of the electrical power distribution system when the second frequency is within a second frequency range; and

receiving power transmitted from the electrical power distribution system to the charging energy storage device.

20. The one or more non-transitory computer-readable storage media of claim 17, wherein the method further comprises a step for generating a regulation signal causing a charging system to perform the acts of discharging the energy storage device and delivering the power.

21. A system, comprising:

one or more processing units;

the one or more non-transitory computer-readable storage media of claim 17; and

an interface to a bi-directional charger operable to charge and discharge the energy storage device responsive to the processing units executing computer-readable instructions stored on the computer-readable storage media.