A method for handling DC side faults of flexible DC power grids

A processing method, a flexible DC technology, applied in the fault location, detection of faults according to conductor types, electrical components, etc., can solve the problems of DC grid outage, increased investment cost of converter stations, and inability to completely isolate DC faults, etc. The effect of fast and accurate isolation

Active Publication Date: 2021-10-15
CHINA ELECTRIC POWER RES INST +2
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

For example, the "handshake principle" discloses identifying and isolating faulty lines by detecting DC line voltage and controlling AC circuit breakers and DC switches. Tens of milliseconds are slow, and the system recovery time is long, so it may cause harm to the operation of the DC grid and the AC grid connected to it
Secondly, although self-blocking MMC can be used for fault isolation on the DC side, this type of MMC increases the investment cost of the converter station, and can only avoid the overcurrent of the converter itself, but cannot completely isolate the DC fault. resulting in short-term outages of all converter stations in the DC grid

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
  • A method for handling DC side faults of flexible DC power grids
  • A method for handling DC side faults of flexible DC power grids
  • A method for handling DC side faults of flexible DC power grids

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. In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

[0036] The DC line impedance in the DC grid is small, and the fault current rises quickly. Once the DC line in a certain area of ​​the DC grid fails, all the DC circuit breakers in the area may "feel" the existence of the fault curre...

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 method for processing faults on the DC side of a flexible DC power grid. The method includes: calculating the auxiliary inductance parameters for DC side fault protection of the DC power grid; detecting the fault parameters of the DC power grid, and judging the fault location according to the parameters; position action. The technical solution provided by the invention can quickly and accurately isolate faulty lines, ensure that non-faulty parts continue to operate normally during the fault process, and realize reliable protection for DC faults. The selection principle of the auxiliary inductance of the DC circuit breaker provided by the invention can solve the problem of insufficient discrimination of DC faults and realize the protection selectivity.

Description

technical field [0001] The invention belongs to the field of safety and protection of direct current power grids, and in particular relates to a method for processing faults on the direct current side of a flexible direct current power grid. Background technique [0002] High voltage direct current grid (HVDC grid) technology is one of the effective methods to solve large-scale new energy collection, long-distance transmission and large-scale consumption. Among them, the modular multilevel converter (MMC) has become the first choice for the construction of HVDC grid converter stations due to its characteristics of bidirectional power flow, no commutation failure, and fast decoupling control of active and reactive power. Technical solutions. [0003] Although the MMC-based HVDC grid has many advantages, it still faces many unresolved technical problems, especially the protection of the grid under DC faults, such as fault identification, location, and isolation. Since the im...

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 Patents(China)
IPC IPC(8): H02H7/26G01R31/08
CPCG01R31/086H02H7/268Y04S10/52
Inventor 姚良忠王志冰李琰吴婧刘超魏春霞
Owner CHINA ELECTRIC POWER RES INST
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