GRID REGULATION SERVICES FOR ENERGY STORAGE DEVICES BASED ON GRID FREQUENCY

• US 20110245987A1
• Filed: 04/06/2010
• Published: 10/06/2011
• Est. Priority Date: 04/06/2010
• Status: Active Grant

• Current Assignee: Battelle Memorial Institute
• Original Assignee: Battelle Memorial Institute
• Inventors: Tuffner, Francis K., Kintner-Meyer, Michael C. W., Hammerstrom, Donald J., Pratt, Richard M.
• Granted Patent: US 8,478,452 B2
• Time in Patent Office: Days
• US Class Current: 700/295
• 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:

receiving data representing one or more electrical characteristics of an electrical power distribution system;

using a computer processor, selecting a charging rate for a bi-directional charging system based on the data, the bi-directional charging system being operable to charge or discharge an energy storage device; and

generating a regulation signal for causing the bi-directional charging system to discharge the energy storage device, the regulation signal being based at least in part on the selected charging rate.

2. The method of claim 1, wherein the data includes frequency data representing an instantaneous frequency measurement of the electrical power distribution system.

3. The method of claim 2, further comprising computing an average frequency from the frequency data.

4. The method of claim 1, further comprising generating a regulation signal for causing the bi-directional charging system to charge the energy storage device, the regulation signal being based at least in part on the selected charging rate.

5. The method of claim 1, wherein the data includes frequency data representing an instantaneous frequency of the electrical power distribution system and an average frequency of the electrical power distribution system.

6. The method of claim 1, wherein the charging rate is negative.

7. The method of claim 1, further comprising receiving status data representing the status of the energy storage device, and wherein the selecting is based, at least in part, on the status data.

8. The method of claim 7, wherein the status data includes data representing a state-of-charge of the energy storage device.

9. The method of claim 1, further comprising receiving time data representing a desired final charging time, and wherein the selecting is based, at least in part, on the time data.

10. The method of claim 1, further comprising receiving an upper frequency parameter defining an over-frequency event of the electrical power distribution system, a lower frequency parameter defining an under-frequency event of the electrical power distribution system, and wherein the selecting is based at least in part on one or more of the upper frequency parameter and the lower frequency parameter.

11. The method of claim 1, further comprising receiving data representing an actual charging or discharging rate of the energy storage device.

12. The method of claim 1, further comprising discharging the energy storage device responsive to the regulation signal, thereby transmitting power to the electrical power distribution system.

13. The method of claim 1, wherein the energy storage device comprises a battery in an electric vehicle or a plug-in hybrid electric vehicle.

14. The method of claim 1, wherein the energy storage device comprises a stationary power source.

15. The method of claim 1, wherein the energy storage device comprises pumped water storage.

16. The method of claim 1, wherein the energy storage device comprises a flywheel.

17. The method of claim 1, wherein the energy storage device comprises a battery-supplemented photovoltaic power system.

18. The method of claim 1, wherein the electrical power distribution system includes an alternating current power supply.

19. The method of claim 1, wherein the data includes voltage data representing an operating voltage of the electrical power distribution system.

20. The method of claim 1, wherein the bi-directional charging system includes an AC-to-DC battery charger and a DC-to-AC grid-tie inverter.

21. The method of claim 1, further comprising clamping the charging 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.

22. One or more non-transitory computer-readable storage media storing computer-readable instructions that when executed by a computer cause the computer to perform the method of claim 1.

23. 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:

receiving data representing one or more electrical characteristics of an electrical power distribution system;

selecting a charging rate for a bi-directional charging system based on the data, the bi-directional charging system being operable to discharge an energy storage device to the electrical power distribution system; and

generating a regulation signal for causing the bi-directional charging system to discharge the energy storage device, the regulation signal being based at least in part on the selected charging rate.

24. The computer-readable storage media of claim 23, wherein the data includes frequency data representing an instantaneous frequency of the electrical power distribution system.

25. The computer-readable storage media of claim 24, wherein the selecting comprises computing a difference between the instantaneous frequency and an average of previously received instantaneous frequency data.

26. The computer-readable storage media of claim 23, wherein the selecting comprises:

computing an average of previously received data representing one or more electrical characteristics;

computing a difference between the received data and the average;

if the difference indicates that the electrical power distribution system has excess energy, selecting the charging rate to charge the energy storage device; and

if the difference indicates that the electrical power distribution system has a shortage of energy, selecting the charging rate to discharge the energy storage device.

27. A system, comprising:

one or more processing units;

one or more non-transitory computer-readable storage media storing computer-readable instructions that when executed by the processing units determine a charging rate for a bi-directional charger using;

a data input module operable to receive data representing one or more electrical characteristics of an electrical power distribution system;

a logic module operable to determine the charging rate for the bi-directional charger using the data; and

a data output module operable to send charger output rate data representing the determined charging rate.

28. The system of claim 27, wherein the data includes frequency data representing an instantaneous frequency of the electrical power distribution system.

29. The system of claim 27, wherein the charging rate of the bi-directional charger is negative.

30. The system of claim 27, wherein the charging rate of the bi-directional charger indicates that the bi-directional charger is to discharge.

31. The system of claim 27, further comprising the bi-directional charger, the bi-directional charger being configured to receive power from or deliver power to the electrical power distribution system in response to the charger output rate data.

32. The system of claim 27, wherein the charging rate is based at least in part on one or more of:

status data representing the status of the energy storage device, time data representing a desired final charging time, or an actual charging or discharging rate of the energy storage device.

33. The system of claim 27, wherein the data input module is operable to receive an upper frequency parameter defining an over-frequency event of the electrical power distribution system, a lower frequency parameter defining an under-frequency event of the electrical power distribution system, or both the upper frequency parameter and the lower frequency parameter, and wherein the determining is based at least in part on one or more of the upper frequency parameter and the lower frequency parameter.

34. The system of claim 27, further comprising an energy storage device operable to generate power in the electrical power distribution system responsive to the charger output rate data.

35. A method comprising:

transmitting electrical power from an electrical power distribution system to energy storage devices; and

receiving electrical power at the electrical power distribution system from one or more of the energy storage devices in response to a measured instantaneous frequency of the electrical power distribution system, wherein the one or more energy storage devices transmit power to the electrical power distribution system in response to a deviation of the measured instantaneous frequency of the electrical power distribution system from an average frequency of the electrical power distribution system.

36. The method of claim 35, further comprising providing a regulation signal causing the energy storage devices to transmit the power to the electrical power distribution system.

37. The method of claim 36, wherein the providing is performed by a charging station.

38. A method, comprising:

monitoring a frequency of an electrical power distribution system; and

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

39. The method of claim 38, wherein the discharging rate is based at least in part on an average frequency derived from the frequency of the electrical power distribution system.

40. The method of claim 38, wherein the discharging rate is based on a state-of-charge of the energy storage device.

41. The method of claim 38, 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.

42. One or more non-transitory computer-readable storage media storing computer-readable instructions that when executed by a computer cause the computer to perform the method of claim 38.

43. A method, comprising:

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

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

44. The method of claim 43, wherein the discharging occurs responsive at least in part to an average frequency derived from the frequency of the electrical power distribution system.

45. The method of claim 43, wherein the discharging occurs responsive to a state-of-charge of the energy storage device exceeding a predefined value.

46. The method of claim 43, wherein the discharging occurs responsive to a pre-determined or user-selected completion time for charging the energy storage device.

47. One or more non-transitory computer-readable storage media storing computer-readable instructions that when executed by a computer cause the computer to perform the method of claim 43.

48. A system, comprising:

data input means operable to receive data representing one or more electrical characteristics of an electrical power distribution system;

logic means operable to determine the charging rate for a bi-directional charger using the data; and

a data output module operable to send charger output rate data representing the determined charging rate.

49. The system of claim 48, further comprising a bi-directional charger coupled with the data output module.

50. The system of claim 49, further comprising energy storage means coupled to the bi-directional charger.