Multi-terminal flexible direct-current power distribution network-oriented protection method based on voltages of current-limiting inductors

A technology of DC distribution network and current-limiting inductance, which is applied in the direction of emergency protection circuit devices, electrical components, emergency protection detection, etc., and can solve problems such as the inability to meet the protection quickness and selectivity requirements of multi-terminal flexible DC distribution network. To achieve the effect of satisfying the selectivity

Active Publication Date: 2020-01-07
TAIYUAN UNIV OF TECH
View PDF1 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] In order to solve the deficiency that the existing technology cannot meet the protection quickness and selectivity requirements of the multi-terminal flexible DC distribution network, the present invention proposes a multi-terminal flexible DC distribution network protection method based on the current-limiting inductance voltage

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
  • Multi-terminal flexible direct-current power distribution network-oriented protection method based on voltages of current-limiting inductors
  • Multi-terminal flexible direct-current power distribution network-oriented protection method based on voltages of current-limiting inductors
  • Multi-terminal flexible direct-current power distribution network-oriented protection method based on voltages of current-limiting inductors

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0046]The present invention includes a multi-terminal annular DC power distribution system. The multi-terminal annular DC power distribution system includes a converter, a DC circuit breaker and a DC line. The converter adopts a two-level voltage source converter (voltage source converter, VSC), like figure 1 shown.

[0047] figure 1 Middle: S1~S4 represent the AC system; VSC1~VSC4 are converters; Bus1~Bus4 are DC buses; 12, 14, 2123, 32, 34, 41, 43 respectively represent the numbers of DC circuit breakers; Line1~Line4 are DC transmission Lines; F1-F4 are fault points, among which: F1 is on Line1, F2 is on Line2, F3 is on Line4, and F4 is on Bus2 DC bus. The DC circuit breaker is installed at the outlet of the DC bus bar, and the current-limiting inductor is installed between the DC circuit breaker and the DC transmission line. Each transmission line includes two lines of positive and negative poles.

[0048] against figure 1 The four-terminal flexible DC power distributio...

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 multi-terminal flexible direct-current power distribution network-oriented protection method based on the voltages of current-limiting inductors. The method comprises the steps of fault starting, fault detection, fault identification and fault pole selection. According to the fault starting, du/dt and di/dt are adopted as criteria. According to the fault detection, low-voltage and over-current protection is adopted to detect whether a line fails or not. According to the fault identification, internal and external faults can be reliably identified on the basis of the voltages of the current-limiting inductors at two ends of a direct-current line. According to the fault pole selection, whether a positive pole, a negative pole or a bipolar fault occurs in a system isdetermined on the basis of the voltages of the current-limiting inductors at two ends of the direct-current line. After a corresponding fault is detected, a tripping signal is sent out, a corresponding direct-current circuit breaker acts, and the fault is removed. With the method of the invention adopted, the problem that the quickness of a traditional direct-current power distribution network protection is poor is solved. Fault identification is carried out through the voltages at the two ends o of the current-limiting inductors.

Description

technical field [0001] The invention relates to a DC protection scheme, in particular to a voltage source converter (VSC)-based multi-terminal flexible DC distribution network protection method. Background technique [0002] In recent years, with the development of power electronics technology and DC energy storage devices, great changes have taken place in the power supply and load in the power system, and the proportion of distributed power supply in the power supply is getting higher and higher. Various DC The load is connected to the grid through the converter. When using the traditional AC distribution network to realize the consumption of distributed power sources and DC loads, it needs to be connected to the AC distribution network through multi-level converter stations, and the investment of a large number of power electronic equipment increases the investment cost. Compared with the AC power distribution system, the DC power distribution network has the advantages ...

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): H02H7/26H02H7/28
CPCH02H7/268H02H7/28H02H1/0007
Inventor 秦文萍上官鑫任春光夏福良刘翼肇左鹏飞常潇王金浩王磊孟润泉
Owner TAIYUAN UNIV OF TECH
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