Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Composite direct current power modulation method for out-of-limit control of alternating current section power

A DC power modulation and section power technology, applied in the field of modulation, can solve the problems of long operation period, difficulty in meeting the stability control of cross-regional power grid, and loss of stability of the system, and achieve the effect of improving transient and dynamic stability characteristics

Active Publication Date: 2015-05-06
STATE GRID CORP OF CHINA +1
View PDF1 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, if the system oscillation is caused by some uncertain fault that leads to a power shortage in the regional power grid (such as shutdown, DC blocking, etc.), when the system oscillation gradually subsides, the AC grid may still be in an unsafe state, such as The frequency of the regional power grid is suspended, and the transmission power of the cross-region tie line is close to or exceeds the limit of temporary stability / static stability. At this time, the DC modulation function no longer operates, which may cause the system to lose stability.
[0004] For the power shortage of the regional power grid caused by the above-mentioned uncertain faults, the power grid is usually regulated through low-cycle load shedding, AGC (automatic generation control) or frequency modulation of the direct current transmission system, but these methods usually have a shorter action period. Long time and slow response, it is difficult to meet the requirements for stability control of cross-regional power grids

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
  • Composite direct current power modulation method for out-of-limit control of alternating current section power
  • Composite direct current power modulation method for out-of-limit control of alternating current section power
  • Composite direct current power modulation method for out-of-limit control of alternating current section power

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0035] The present invention will be described in further detail below in conjunction with the accompanying drawings.

[0036] The system oscillation that occurs in the inter-regional interconnection grid is usually reflected in the power fluctuation of the AC tie line between the large regions. The power of the AC tie line is used as the input of the DC power modulation function to control the transmission, which can directly reflect the system oscillation and effectively suppress the system oscillation. Therefore, the present invention uses the power of the AC tie line as the control input, while using the DC power modulation signal to suppress the power fluctuation of the tie line, and at the same time judge whether the power of the tie line reaches a certain limit value, thereby triggering the DC power emergency control function to maintain Transient and dynamic stability of interregional power grids.

[0037] Such as figure 1 , the present invention provides a kind of D...

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 provides a composite direct current power modulation method for out-of-limit control of alternating current section power, including the following steps of: calculating direct current power modulation quantity Pmod by alternating current tie line power Pac, to achieve control on fluctuation of the alternating current section power; judging whether the alternating current section power is out of limit by the alternating current tie line power Pac, and if yes , executing the step 3; calculating direct current power emergency control quantity Pemg, and thereby completing the out-of-limit control of alternating current section power. According to composite direct current power modulation method for the out-of-limit control of the alternating current section power, through compounding the direct current power emergency control function on the general direct current power modulation function, an additional monitoring device is not required, namely, the power vacancy of the regional power grid is compensated by emergency power control while achieving the cross-distinct power grid alternating current tie line power fluctuation, the steady state stability limit of the alternating current tie line is kept undamaged, and thereby the transient state and dynamic stability characteristics of the large area interconnected power grid with the complex operation mode and under the complex operating condition can be improved at the same time.

Description

technical field [0001] The invention relates to a modulation method, in particular to a direct current power modulation method for compound alternating current section power over-limit control. Background technique [0002] For the AC-DC hybrid grid, the application of DC power modulation technology can suppress the power / voltage / frequency fluctuations of the AC grid. The DC power modulation technology calculates the modulation quantity by collecting the electrical quantity of the AC system and designing a letter, and sends the calculation result to the controlled DC to modulate the DC transmission power, so as to suppress the system oscillation. [0003] The commonly used DC power modulation technology damps the system oscillation by continuously changing the DC transmission power. When the system oscillation is suppressed, the DC transmission system will gradually recover to the transmission power before the fault. However, if the system oscillation is caused by some unce...

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): H02J3/24
Inventor 胡涛张晋华张文朝吴子平
Owner STATE GRID CORP OF CHINA
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products