A Method for Protecting Internal Ground Faults of AC and DC Filter Capacitors

A DC filter, ground fault technology, applied in emergency protection circuit devices, emergency protection devices with automatic disconnection, electrical components, etc., to ensure safe operation and improve protection sensitivity.

Active Publication Date: 2018-05-01
NR ELECTRIC CO LTD +1
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The value range of delay T is 0~10.0s

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 Protecting Internal Ground Faults of AC and DC Filter Capacitors
  • A Method for Protecting Internal Ground Faults of AC and DC Filter Capacitors
  • A Method for Protecting Internal Ground Faults of AC and DC Filter Capacitors

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0016] The technical solutions of the present invention will be described in detail below in conjunction with the accompanying drawings.

[0017] The invention provides an internal grounding fault protection method of AC and DC filter capacitors, which detects the internal grounding faults of AC and DC filter capacitors by using the principle of simultaneously meeting the AC and DC filter differential protection and filter unbalance protection.

[0018] Such as figure 1 The position of the current measuring point is shown, and the real-time CT sampling obtains the filter head-end current IT1, tail-end current IT2 and unbalanced current IT3.

[0019] Such as figure 2 Shown is the logic block diagram of the protection principle, using the principle of both AC and DC filter differential protection and filter unbalance protection to detect the internal ground fault of the AC and DC filter capacitors. Real-time CT sampling to obtain the head-end current, tail-end current and unb...

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 an internal grounding fault protection method of AC and DC filter capacitors. The steps are: real-time sampling of filter head-end current, tail-end current and unbalanced current; adopting the differential protection principle of head-end current and tail-end current ( P1); using the unbalanced protection principle (P2) of unbalanced current; performing logical AND operation on the action results of the two protection principles (P1 and P2), and obtaining the protection method of this patent. This method uses the principle of combining filter differential protection and filter unbalance protection to detect the ground fault inside the filter capacitor, avoiding the filter failure caused by reducing the differential protection setting or reducing the unbalance protection setting to increase the protection sensitivity. Protect the risk of misoperation and ensure the safe operation of DC equipment.

Description

technical field [0001] The invention belongs to the field of DC transmission protection and a related protection device, in particular to a method for protecting the internal grounding fault of AC and DC filter capacitors. Background technique [0002] AC and DC filters are important equipment in the converter station. The AC filter is installed at the AC bus end to provide reactive power compensation and filter harmonics for the converter station; the DC filter is installed in parallel at the DC pole bus and neutral Between the bus bars is the most effective means to suppress the harmonics on the DC side of the DC transmission system. [0003] Filter differential protection and filter unbalance protection are two existing independent principles of protection. [0004] When the ground fault occurs in the AC and DC filters, the differential current at the head and tail ends of the filter will be generated to varying degrees; when the fault differential current is small, it w...

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): H02H7/00H02H3/26
Inventor 赵森林刘乔王俊生
Owner NR ELECTRIC CO LTD
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