Modular multilevel converter open-circuit fault diagnosis method based on quartile

A modular multi-level, open-circuit fault technology, applied in the direction of instruments, measuring electricity, measuring electrical variables, etc., can solve the problems of complicated fault diagnosis process and prolong fault diagnosis time, so as to achieve easy understanding and implementation, and prolong fault diagnosis Time, the effect of realizing fault detection and location

Inactive Publication Date: 2020-04-10
SOUTHEAST UNIV
View PDF4 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

All these methods need to perform fault detection and fault localization separately, which not only complicates the fault diagnosis process, but also prolongs the required fault diagnosis time

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
  • Modular multilevel converter open-circuit fault diagnosis method based on quartile
  • Modular multilevel converter open-circuit fault diagnosis method based on quartile
  • Modular multilevel converter open-circuit fault diagnosis method based on quartile

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0030] Embodiments of the invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below by referring to the figures are exemplary only for explaining the present invention and should not be construed as limiting the present invention.

[0031] Aiming at the problem of open-circuit faults in sub-modules, the present invention proposes a sub-module fault diagnosis method suitable for MMC, wherein the MMC topology is composed of six bridge arms, such as figure 1 As shown, each bridge arm contains N identical submodules (Submodule, SM) and a bridge arm inductance L s , the sub-module adopts a half-bridge structure, and each sub-module consists of two power switches S u , S l , two diodes D u 、D l Composed of a DC capacitor, the capacitor voltage balance method is: according to the comparison between the reference voltage of the bridge arm and the carrier wave, the number of sub-modules that need to be i...

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 modular multilevel converter open-circuit fault diagnosis method based on quartile. The method comprises the following steps: providing a variance-based capacitor voltage change quantitative index, namely a VAR index; calculating VAR values of all sub-modules to form a data set Q; the first quartile and the third quartile of the data set Q forming the upper boundary valueand the lower boundary value of the VAR value, comparing the VAR value of each sub-module with the upper boundary value and the lower boundary value, judging whether the VAR value of each sub-modulereaches the fault standard or not, and fault detection and positioning can be achieved at the same time. In addition, the quartile analysis result can also mark a specific fault switch device in the sub-module, so that fault classification is realized, and the fault-tolerant control of the sub-module is more flexible. According to the invention, only the sub-module capacitor voltage is involved, and extra hardware resources are not needed. The occurrence of single or multiple faults can be correctly handled, and system parameters are not involved, so that the method is not influenced by parameter uncertainty and has very high robustness.

Description

technical field [0001] The invention relates to a quartile-based open-circuit fault diagnosis method for a modular multilevel converter, and belongs to the technical field of multilevel power electronic converters. Background technique [0002] Compared with traditional two-level and three-level converters, modular multilevel converters (ModularMultilevel Converter, MMC) have the characteristics of high efficiency, small output AC voltage harmonics, and high modularity, and are more suitable for high voltage , high-power applications, and has broad prospects in flexible DC transmission, medium-voltage motor drives and other fields. [0003] By dividing the bulk DC capacitance into smaller capacitors, series-connected sub-modules (SM) can be implemented in MMCs. This unique structure results in no large-capacity DC capacitors, lower switching synchronization requirements and a higher degree of modularity. However, a large number of series-connected submodules poses a huge t...

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): G01R31/56G01R31/54
Inventor 王宝安邓富金金铭
Owner SOUTHEAST UNIV
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap