Method for quickly and effectively inhibiting frequency fluctuation of island power grid

A power grid frequency and sea island technology, applied in the field of power transmission and distribution, can solve the problems of reducing frequency changes, slow response speed of governors, and inability to adjust system frequency in time, so as to maintain frequency stability, suppress frequency fluctuations, and maintain active power balanced effect

Inactive Publication Date: 2011-03-30
ELECTRIC POWER RES INST OF STATE GRID ZHEJIANG ELECTRIC POWER COMAPNY +2
View PDF4 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] Under normal circumstances, when the active power of the grid is out of balance, the generator speed control system starts to operate, but due to the slow response speed of the speed governor, the system frequency cannot be adjusted in time
Although the wind farm based on DFIG can decouple its active power and reactive power, due to the complete decoupling control of the speed of DFIG and the frequency of the grid, the DFIG cannot be controlled when the frequency of the grid changes. Provides frequency response to the grid and cannot help the grid reduce the rate of frequency change
Therefore, the existing methods cannot effectively suppress the impact of impact loads and wind farm output changes on the island power grid frequency

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for quickly and effectively inhibiting frequency fluctuation of island power grid
  • Method for quickly and effectively inhibiting frequency fluctuation of island power grid
  • Method for quickly and effectively inhibiting frequency fluctuation of island power grid

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0021] The VSC-HVDC system structure is as follows figure 1 As shown, Uc is the fundamental wave component of the converter output voltage; Us is the fundamental wave component of the AC bus voltage; δ is and The phase angle difference between them; the converter adopts PWM control, and m is the modulation degree. By adjusting δ and m, the active power and reactive power of VSC-HVDC can be quickly controlled.

[0022] In the present invention, the VSC-HVDC system supplies power to the island load, such as figure 2 As shown, the island equivalent generator capacity is 120MW. The VSC-HVDC system adopts constant DC voltage on the rectifier side, constant active power on the inverter side and AC bus voltage control mode, and a constant active power control schematic diagram with a frequency correction module on the inverter side. Such as image 3 shown. When the island power grid is affected by the impact load, the two control modes of VSC-HVDC without frequency correction...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a method for quickly and effectively inhibiting frequency fluctuation of an island power grid. The conventional methods cannot effectively inhibit the influence of impact load and wind power field output change on the frequency of the island power grid. The invention adopts the technical scheme that: a frequency correction module is arranged in a constant active power controller on the inverter side of voltage source converter high-voltage direct current (VSC-HVDC), the power set value of the constant active power controller can track the change of system frequency through the frequency correction module, and the power fed into the island power grid is changed by using the quick response property of a voltage source converter (VSC) so that the island power grid still keeps active power balance under the action of impact load and during abrupt change of the wind power field output and the frequency of the system is kept stable.

Description

technical field [0001] The invention relates to the technical field of power transmission and distribution, in particular to a method for rapidly and effectively suppressing frequency fluctuations of sea-island power grids in a flexible DC power transmission project. Background technique [0002] With the vigorous development of flexible direct current transmission technology, flexible direct current transmission technology (VSC-HVDC) is widely used in the field of power transmission and distribution. Because VSC can work in passive mode, it becomes the first choice for delivering power to isolated loads in sea islands. As an isolated small power grid, the isolated island has certain special loads. Taking the Shengsi island power grid as an example, in addition to the conventional load on the island, it also includes the load of the transfer terminal. This type of load is the loading and unloading port machinery and marine motor of the ore transfer terminal. The random fluc...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H02J1/02
Inventor 陆翌赵成勇胡静岳伟杨晓东
Owner ELECTRIC POWER RES INST OF STATE GRID ZHEJIANG ELECTRIC POWER COMAPNY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products