WIND POWER GENERATION SYSTEM OF A TYPE PROVIDED WITH POWER STORAGE SYSTEM

• US 20090295162A1
• Filed: 08/12/2009
• Published: 12/03/2009
• Est. Priority Date: 09/27/2007
• Status: Active Grant

• Current Assignee: Hitachi Engineering & Services Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi Engineering & Services Company Limited (Hitachi, Ltd.)
• Inventors: Iwata, Takeshi, Oohara, Shinya, Hoshino, Naoki
• Granted Patent: US 8,334,606 B2
• Time in Patent Office: Days
• US Class Current: 290/44
• CPC Class Codes: F03D 7/028 controlling wind motor output power
• CPC Class Codes: F03D 7/048 controlling wind farms
• CPC Class Codes: F03D 9/11 storing electrical energy
• CPC Class Codes: F03D 9/257 the wind motor being part of a wind farm
• CPC Class Codes: F05B 2210/16 Air or water being indistinctly used as working fluid, i.e. the machine can work equally with air or water without any modification
• CPC Class Codes: F05B 2210/18 Air and water being simultaneously used as working fluid
• CPC Class Codes: H02J 2300/28 The renewable source being wind energy wind motors F03D
• CPC Class Codes: H02J 3/32 using batteries with converting means
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 7/34 Parallel operation in networks using both storage and other dc sources, e.g. providing buffering H02J7/14 takes precedence
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction
• CPC Class Codes: Y02E 10/76 Power conversion electric or electronic aspects
• CPC Class Codes: Y02E 70/30 Systems combining energy storage with energy generation of non-fossil origin

Abstract

A wind power generation system having a group of wind turbine generators includes a superior controller having a generation power recording memory to record a sum of a generation power of the group of wind turbine generators and a charge and discharge power of a power storage system, a charge and discharge power command computing device for computing a charge and discharge power command for the power storage system in a second period by making use of information of the output power in a first period computed in the output power computing unit and information of a detection value at the present of the generation power recording memory, and a charge and discharge power control device.

Claims

1. A wind power generation system including a group of wind turbine generators constituted by more than one wind turbine generators, a power storage system constituted by more than one power storage devices, a superior controller to control the group of the wind turbine generators and the power storage system, and a generation power detector to detect a generation power of the group of the wind turbine generators, wherein the superior controller comprising:

a generation power recording memory to record a sum of a generation power of the group of wind turbine generators and a charge and discharge power of the power storage system,

a charge and discharge power command computing device for computing a charge and discharge power command for the power storage system in a second period by making use of information of the output power in a first period computed in the output power computing unit and information of a detection value at the present of the generation power recording memory, when assuming that a predetermined period from a past to present as the first period and another predetermined period from the present to a future as the second period, and

a charge and discharge power control device for controlling the charge and discharge power according to the charge and discharge power command by the power storage system.

2. A wind power generation system according to claim 1, wherein the superior controller further comprising:

a maximum value and minimum value computing unit for determining the maximum value and the minimum value of the output power in the first period;

an output range computing unit for determining an output range of the output power in the second period from the maximum value and the minimum value; and

for an instance when the generation power of the group of wind turbine generators deviates from the output range in the second period, a charge and discharge power command computing unit for computing the charge and discharge power command of the power storage system from a power deviated from the output range.

3. A wind power generation system according to claim 2, the superior controller further comprising:

a target charge rate range computing unit for computing a target charge rate range with regard to charge rate of the power storage system;

for an instance when the generation power of the group of wind turbine generators deviates from the output range or when the charge rate of the power storage system deviates from the target charge rate range, a charging or discharging device for charging or discharging by the power storage system.

4. A wind power generation system according to claim 3, the superior controller further comprising:

a target charge rate range determining unit for determining the target charge rate range of the power storage system from the generation power of the group of wind turbine generators.

5. A wind power generation system according to claim 2, the superior controller further comprising:

a first order delay computing unit for computing a first value obtained by applying a first order delay to the generation power of the group of wind turbine generators;

for an instance when the first value is within the output range, a charge and discharge control unit for causing to perform the charge and discharge control of the power storage system so that the output power of the wind power generation system follows up the first value; and

for an instance when the first value deviates from the output range, a charge and discharge command preparing unit for preparing the charge and discharge command of the power storage system so that the output power of the wind power generation system follows up an upper limit or a lower limit of the output range.

6. A wind power generation system according to claim 1, characterized in that the first period is a fixed value less than 20 minutes and the second period is a fixed value less than one minute.

7. A wind power generation system according to claim 2, characterized in that the first period is a fixed value less than 20 minutes and the second period is a fixed value less than one minute.

8. A wind power generation system according to claim 2, characterized in that an upper limit value of the output range is a value obtained by adding a first predetermined value to the minimum value, a lower limit value of the output range is a value obtained by subtracting the first predetermined value from the maximum value and the first predetermined value is a fixed value set in relation to an allowable variation width of the output power of the wind power generation system.

9. A wind power generation system according to claim 1, the superior controller further comprising:

a receiving unit for receiving a generation power prediction value for predicting a generation power of the group of wind turbine generators in future; and

an adjusting unit of target charge rate range for adjusting the target charge rate range in response to the generation power prediction value.

10. A wind power generation system according to claim 1, the superior controller comprising:

a power limiting command preparing unit for preparing a power limiting command of the group of wind turbine generators, and

characterized in that

the group of wind turbine generators comprising a generation power limiting unit for limiting the generation power below the power limiting command.

11. A wind power generation system according to claim 1, the superior controller further comprising:

a power limiting command preparing unit for preparing a power limiting command of the group of wind turbine generators,

a minimum value of the output power determining unit for determining the minimum value of the output power in the first period; and

a chargeable power computing unit for computing a chargeable power of the power storage system, and

characterized in that

the group of wind turbine generators comprising a generation power limiting unit for limiting the generation power below the power limiting command; and

a power limiting command preparing unit for preparing a power limiting command prepares a sum of the minimum value, the chargeable power and the fixed value set in relation to an allowable variation width of the output power of the wind power generation system as the power limiting value.

12. A wind power generation system according to claim 1, the superior controller further comprising:

a power limiting command computing unit for computing a power limiting command of the group of wind turbine generators, and

characterized in that

the group of wind turbine generators comprising a generation power limiting unit for limiting the generation power thereof below the power limiting command, and

further characterized by comprising;

a receiving unit for receiving a generation power prediction value of the wind power generation system; and

a power limiting command varying unit for varying the power limiting command in response to the generation power prediction value.

13. A wind power generation system according to claim 11, the superior controller further comprising:

a output power upper limit command computing unit for computing an output power upper limit command of the output power; and

a output power limiting unit for limiting the output power below the output power limit command through a charging operation of the power storage system and a power limiting operation of the group of wind turbine generators.

14. A wind power generation system according to claim 12, the superior controller further comprising:

a output power upper limit command computing unit for computing an output power upper limit command of the output power; and

a output power limiting unit for limiting the output power below the output power limit command through a charging operation of the power storage system and a power limiting operation of the group of wind turbine generators.

15. A wind power generation system according to claim 13, characterized in that

the output power upper limit command is a fixed value and is below a value of generation power rating of the group of wind turbine generators as well as is above a rated capacity of a converter constituting the power storage system.

16. A wind power generation system according to claim 14, characterized in that

the output power upper limit command is a fixed value and is below a value of generation power rating of the group of wind turbine generators as well as is above a rated capacity of a converter constituting the power storage system.

17. A wind power generation system according to claim 13, characterized in that,

the output power upper limit command is adjusted in response to the generation power prediction value.

18. A wind power generation system according to claim 14, characterized in that,

the output power upper limit command is adjusted in response to the generation power prediction value.

19. A wind power generation system according to claim 13, characterized in that,

the output power upper limit command is adjusted in response to the charge rate of the power storage system or an accumulated energy of the power storage system.

20. A wind power generation system according to claim 14, characterized in that,

the output power upper limit command is adjusted in response to the charge rate of the power storage system or an accumulated energy of the power storage system.

21. A wind power generation system including a group of wind turbine generators constituted by more than one wind turbine generators and a power storage system constituted by more than one power storage devices comprising:

an output power target value computing unit to compute a target value of output power representing a sum of a generation power of the group of wind turbine generators and a charge and discharge power of the power storage system,

a chargeable power computing unit to compute a chargeable power of the power storage system, and

a power limiting command preparing unit to prepare a power limiting command for the group of wind turbine generators based on a sum of the output power target value and the chargeable, and

wherein, the group of wind turbine generators limits the generation power based on the power limiting command.