Wind power bundling control method after wind power and thermal power are connected to grid

Patent metadata

Field	Value
Publication number	US-9667066-B2
Application number	US-201414649202-A
Country	US
Kind code	B2
Filing date	Apr 16, 2014
Priority date	Apr 17, 2013
Publication date	May 30, 2017
Grant date	May 30, 2017

Abstract

The present invention has disclosed a wind power bundling control method after wind power and thermal power are connected to a power grid in the field of electric power system security technology, including regulating wind power output and thermal power output forward or backward; calculating the transient stability margin of the grid, load level index of element and voltage out-of-limit index of busbar after regulating wind power output and thermal power output respectively; calculating wind power/thermal power paying value according to the transient stability margin of the grid, load level index of element and voltage out-of-limit index of busbar after regulating wind power output and thermal power output; if wind power/thermal power paying value is larger than set threshold value, regulating wind power output and thermal power output backward/forward; if wind power/thermal power paying value is smaller than set threshold value, regulating wind power output and thermal power output forward/backward. The present invention provides a wind power bundling control method after wind power and thermal power are connected to the power grid to ensure reasonable output of wind power and thermal power, so as to guarantee the power grid operates normally.

First claim

The invention claimed is:

1. A wind power bundling control method after wind power and thermal power are connected to a grid characterized in the method comprises:
step 1: providing initial values for winder power output and thermal power output, regulating wind power output and thermal power output forward under the condition of satisfying transient stability of the grid or regulating wind power output and thermal power output backward under the condition where the transient stability of the grid is not satisfied; wherein regulating wind power output and thermal power output forward refers to decreasing thermal power output and increasing wind power output; and regulating wind power output and thermal power output backward refers to decreasing wind power output and increasing thermal power output;
step 2: calculating a transient stability margin of the grid λ SI ,a load level index of an element λ L and a voltage out-of-limit index of a busbar λ U respectively after regulating wind power output and thermal power output;
step 3: calculating wind power/thermal power paying value according to the transient stability margin of the grid λ SI , the load level index of the element λ L and the voltage out-of-limit index of the busbar λ U after regulating wind power output and thermal power output;
step 4: if wind power/thermal power paying value is larger than preset threshold value, regulating wind power output and thermal power output backward; if wind power/thermal power paying value is smaller than preset threshold value, regulating wind power output and thermal power output forward.

2. The control method according to claim 1 , characterized in that, after the Step 4, the method further comprises determining wind power output and thermal power output after regulating wind power output and thermal power output.

3. The control method according to claim 1 , characterized in that, when calculating transient stability margin of the grid λ SI after regulating wind power output and thermal power output,

λ
Sl

=

∑
γ

⁢

⁢

(

P

i
-
1

P

i
-
0

)

is adopted, wherein, γ is a set of key cross-sections, P i-1 and P i-0 are stability limits of the i cross-section before and after regulating wind power output and thermal power output forward/backward respectively, and 1≦i≦k, k refers to the number of the elements in the set of key cross-sections.

4. The control method according to claim 1 , characterized in that, when calculating load level index of element λ L after regulating wind power output and thermal power output,

λ
L

=

∑

l
∈
α

⁢

⁢

ρ
l

⁡

(

S
l

/

S
l
max

)

2
⁢

⁢
n

is adopted, wherein, α is a set of system elements, namely the set of transmission lines and transformers with voltage class of 330 kV or above; ρ l is a weight factor of a system element l; S l is power of transmission line l; S l max is an upper limit of the power of transmission line l; n is the parameter used to prevent masking effect from happening during calculation.

5. The control method according to claim 1 , characterized in that, when calculating voltage out-of-limit index of busbar λ U after regulating wind power output and thermal power output,

λ
U

=

∑
β

⁢

⁢

ρ
i

⁡

(

U
i

-

U
i
SP

Δ
⁢

⁢

U
i
lim

)

2
⁢

⁢
n

is adopted, wherein, β is a set of the busbar; ρ i is a weight factor of the i busbar; U i is voltage amplitude of the i busbar, U i SP =(U i H +U i L )/2 and ΔU i lim =(U i H −U i L )/2, U i H and U i L referring to an upper limit and a lower limit of voltage amplitude of the i busbar respectively; n is the parameter used to prevent masking effect from happening during calculation.

6. The control method according to claim 1 , characterized in that, when calculating wind power/thermal power paying value according to transient stability margin of the grid λ SI , the load level index of the element λ L and voltage out-of-limit index of the busbar λ U , λ=ω 1 ·λ sl +ω 2 ·λ L +ω 3 ·λ U is adopted, wherein,ω 1 , ω 2 and ω 3 are set weight factors of transient stability margin of the grid, the load level index of element and voltage out-of

Assignees

• Gansu Electric Power Corp Wind Power Tech Center
• State Grid Gansu Eletric Power Corp
• State Grid Corp China
• Univ North China Electric Power

Inventors

• Wang Ningbo
• Liu Wenying
• Ma Yanhong
• Wang Jiaming
• Jin Dan
• Liang Cai
• Zhou Shiyuan
• Wu Xiaodan
• Ding Kun
• Zhao Zilan
• Zhou Qiang
• Yang Bin
• Li Jin
• Xu Peng
• Zhao Long
• Ge Rundong

Classifications

• H02J2101/28

  Wind energy · CPC title

• Y02E10/76

  Power conversion electric or electronic aspects · CPC title

• H02J3/46

  Controlling the sharing of generated power between the generators, sources or networks · CPC title

• Y02E10/763

  Cross-Sectional Technologies · mapped topic

• Y10T307/549

  Cross-Sectional Technologies · mapped topic