BATTERY CONTROL METHODS AND CIRCUITS, AND ENERGY STORAGE TO GRID CONNECTION SYSTEMS

• US 20180138710A1
• Filed: 05/17/2016
• Published: 05/17/2018
• Est. Priority Date: 05/19/2015
• Status: Active Grant

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Kocarev, Ljupco, Zdraveski, Vladimir, Todorovski, Mirko, Gajduk, Andrej, Basnarkov, Lasko
• Granted Patent: US 10,574,057 B2
• Time in Patent Office: Days
• CPC Class Codes: B60L 50/60 using power supplied by batteries in combination with fuel cells B60L50/75
• CPC Class Codes: G05F 1/66 Regulating electric power
• CPC Class Codes: H02J 2310/14 The load or loads being home appliances
• 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: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y02B 70/3225 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y04S 20/222 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y04S 20/242 Home appliances

Abstract

A method measures a power characteristic at the one or more storage batteries, and controls the one or more batteries to selectively act as a generator to supply power to the power grid or to act as a load to draw power from the power grid in response N to a predetermined disturbance in the power characteristic being detected. A system includes a battery charging circuit, a battery to grid circuit and a controller that monitors a power characteristic at the one or more storage batteries, and controls the one or more batteries to selectively act as a generator to supply power to the power grid or to act as a load to draw power from the power grid in response to a predetermined disturbance in the power characteristic being detected.

Claims

1. A method for regulating the power transfer between one of more storage batteries and a power grid, the method comprising measuring a power characteristic at the one or more storage batteries, and controlling the one or more batteries to selectively act as a generator to supply power to the power grid or to act as a load to draw power from the power grid in response to a predetermined disturbance in the power characteristic being detected.

2. The method of claim 1, wherein the power characteristic comprises a local frequency at the one or more storage batteries and the predetermined disturbance comprises a frequency disturbance.

3. The method of claim 2, wherein the controlling comprises controlling the battery to act as a generator to supply power when a first predetermined frequency deviation in the local frequency is detected, and the controlling the battery to act as a load to draw power from the connected power grid when a second predetermined frequency deviation in the local frequency is detected.

4. The method of claim 2, further comprising releasing the battery or batteries from power regulation control when the local frequency is stable.

5. The method of claim 2, wherein the frequency disturbance is determined as a function of the first derivative of the change in local frequency.

8. The method of claim 2, wherein the controlling comprises controlling the battery or batteries to have a battery power output linearly dependent on frequency deviation, with ramp limits of ±

3 kW at ±

100 mHz according to;

10. The method of claim 2, wherein said controlling comprises controlling the battery or batteries to have a battery power output dependent upon a tan h, or a sigmoid function.

11. The method of claim 2, wherein the controlling comprises controlling the battery or batteries to have a battery power output linearly dependent on frequency deviation, with ramp limits of a first predetermined power and a fraction of that power according to:

16. The method of claim 11, wherein the one or more storage batteries comprises a plug-in electrical vehicle or a home battery.

6-7. -7. (canceled)

9. (canceled)

12-15. -15. (canceled)

17. A system for connecting one or more storage batteries to a power grid, the controller comprising a battery charging circuit, a battery to grid circuit and a controller that monitors a power characteristic at the one or more storage batteries, and controls the one or more batteries to selectively act as a generator to supply power to the power grid or to act as a load to draw power from the power grid in response to a predetermined disturbance in the power characteristic being detected, wherein the controlling comprises controlling the battery to act as a generator to supply power when a first predetermined frequency deviation in the local frequency is detected, and the controlling the battery to act as a load to draw power from the connected power grid when a second predetermined frequency deviation in the local frequency is detected.

19. The system of claim 17, wherein the battery to grid circuit comprises a pulse-width modulation signal generator, a grid-tie inverter sub circuit connecting the signal generator with a transformer as its main supply and a referent sine wave generator, the power of the battery to grid circuit depends on the PWM frequency that is regulated by the controller, and a second transformer that powers the battery or batteries and returns power to the power grid.

20. The system of claim 17, wherein the power characteristic comprises a local frequency at the one or more storage batteries and the predetermined disturbance comprises a frequency disturbance.

22. The system of claim 20, further comprising releasing the battery or batteries from power regulation control when the local frequency is stable.

23. The system of claim 20, wherein the frequency disturbance is determined as a function of the first derivative of the change in local frequency.

26. The system of claim 20, wherein the controlling comprises controlling the battery or batteries to have a battery power output linearly dependent on frequency deviation, with ramp limits of ±

3 kW at ±

100 mHz according to;

28. The system of claim 20, wherein said controlling comprises controlling the battery or batteries to have a battery power output dependent upon a tan h, or a sigmoid function.

29. The system of claim 20, wherein the controlling comprises controlling the battery or batteries to have a battery power output linearly dependent on frequency deviation, with ramp limits of a first predetermined power and a fraction of that power according to:

30. The system of claim 29, further comprising releasing the battery or batteries from power regulation control when the local frequency is stable.

34. The system of claim 17, wherein the one or more storage batteries comprises a plug-in electrical vehicle or a home battery.

18. (canceled)

21. (canceled)

24-25. -25. (canceled)

27. (canceled)

31-33. -33. (canceled)