Islanding detecting method

An isolated island detection and isolated island technology, applied in the direction of measuring electricity, measuring devices, measuring electrical variables, etc., can solve the problems of insufficient research on detection methods, reduce power quality, increase detection time, etc., achieve wide applicability, facilitate implementation, reduce The effect of small detection blind spots

Active Publication Date: 2015-08-26
JIANGSU FRONTIER ELECTRIC TECH +1
View PDF5 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Active methods mainly include sliding mode frequency shift method (SMS), active frequency shift method (AFD), Sandia frequency shift method (SFS), etc.; but compared with passive methods, it will reduce power quality and increase detection time
Combining active and passive methods to form a hybrid detection method can not only have the advantages of both active and passive methods, but also overcome their respective shortcomings. However, the current research on effective hybrid detection methods is not deep enough.

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
  • Islanding detecting method
  • Islanding detecting method
  • Islanding detecting method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0026] In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not constitute a conflict with each other.

[0027] figure 1 It is a schematic diagram of a distributed power grid connected to the grid. The distributed power of the system is connected to the grid through an inverter, and the parallel RLC represents the connected load and is connected to the public coupling point PCC, L f Represents the equivalent inductance of the inverter, and the islanding detection function is included in the invert...

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 islanding detecting method which comprises the following steps: acquiring a voltage waveform of a common coupling point and measuring a frequency value, calculating the average change rate in a certain period to obtain a judging signal, comparing the judging signal with the preset change rate threshold value, outputting a control signal, selecting an outputted reference signal of an inverter by the control signal, introducing reference current after phase deviation under the condition that islanding possibly exists by a frequency change rate detection method, realizing further detection according to a sliding mode frequency deviation method, otherwise, introducing non-deviation reference current, and achieving normal operation of the system. The islanding detecting method has the advantages of reducing detection blind zones and impact on the system power quality and increasing the detection speed.

Description

technical field [0001] The invention relates to the technical field of distributed power generation island detection, in particular to an island detection method. Background technique [0002] Today's distributed energy development depends to a certain extent on the operating conditions and protection systems of distributed power generation systems. The integration of distributed generation into the grid has created many problems, one of which has been widely studied is the islanding phenomenon. Islanding is the state in which the load is self-sufficiently powered by the distributed generation system after the grid is disconnected. Unplanned islanding can cause serious damage to power supply and distribution equipment and consumers, and can be a safety threat to grid maintenance personnel. Therefore, in the protection equipment of the distributed generation system, the function of island detection is essential. At present, various detection methods proposed by domestic an...

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): G01R31/00
Inventor 顾文徐钢高蕾杨宏宇王成亮唐一铭李辰龙杜先波
Owner JIANGSU FRONTIER ELECTRIC 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