Photovoltaic system DC side arc fault type identification and protection device

An arc fault and photovoltaic system technology, applied in the field of photovoltaic grid-connected fault detection, to achieve the effect of safety guarantee and preventing misjudgment and missed judgment

Inactive Publication Date: 2018-05-25
上海英孚特电子技术有限公司 +2
View PDF5 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The invention provides a photovoltaic array fault arc detection type identification method and protection device, the purpose is to solve the problem of accurately detecting the fault arc when a DC arc fault occurs in a photovoltaic system, and to be able to identify the type of fault arc, so as to be able to adopt Appropriate circuit protection strategy to extinguish fault arc

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
  • Photovoltaic system DC side arc fault type identification and protection device
  • Photovoltaic system DC side arc fault type identification and protection device
  • Photovoltaic system DC side arc fault type identification and protection device

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0040] In order to describe the present invention more specifically, preferred embodiment is hereby described in detail in conjunction with accompanying drawings as follows:

[0041] figure 2 A method for identifying a type of photovoltaic array fault arc, comprising the following steps:

[0042] (1) Perform current sampling on the DC bus of the photovoltaic array at a sampling rate of 200kHz to obtain current sampling signals;

[0043] (2) Perform high-pass filtering on the current sampling signal, filter out signal components below 10kHz, and obtain high-frequency current signals;

[0044] (3) Calculate and acquire the time-frequency domain characteristics of the high-frequency current sampling signal.

[0045] The process of obtaining the time-frequency domain characteristics of the signal is as follows:

[0046] 1) Calculate the standard deviation of the current sampling high-frequency signal and the time-domain feature vector, as follows:

[0047]

[0048] V=[σ] (...

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 photovoltaic system DC side arc fault type identification and protection device. Through sampling a DC bus current signal of a photovoltaic system and employing the standard deviation to extract signal time-domain characteristics, wavelet analysis is carried out to extract signal frequency domain characteristics, and a time-frequency domain characteristic plane is established; presence of a fault arc at the certain time is detected based on the position of the signal at the characteristic plane, if the fault arc exists, through breaking a DC bus and sampling a photovoltaic array voltage signal, time-frequency characteristics of the voltage signal are extracted to establish a characteristic plane, and presence of a photovoltaic array fault arc is detected for another time to identify a fault arc type; if the voltage detection information has no fault arc signal, the series type fault arc occurs; if the voltage detection information has the fault arc signal, theparallel type fault arc occurs. The invention further provides a photovoltaic system arc fault protection device comprising a sampling unit, a data processing unit and a control unit, and damage of the photovoltaic system DC side fault arc to the system is substantially reduced.

Description

Technical field: [0001] The invention belongs to the field of photovoltaic grid-connected fault detection, and in particular relates to a photovoltaic array fault arc detection and arc type identification method and a protection device. Background technique: [0002] With the rapid development of photovoltaic power generation, fire accidents in photovoltaic systems also occur from time to time, most of which are related to arc faults. There are a large number of connecting devices between photovoltaic modules. Once the insulation layer is aging and fails, the DC voltage of hundreds of volts can break down the air and generate an arc. In addition, an arc fault can also electrify the device, threatening the safety of the operator. In order to prevent such safety issues, the US National Electrical Code NEC (National Electrical Code) No. 690.11 requires that the DC bus voltage of the photovoltaic grid-connected system is greater than 80V to be equipped with fault arc detection ...

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): H02S50/00
CPCH02S50/00Y02E10/50
Inventor 徐文新吴春华李智华
Owner 上海英孚特电子技术有限公司
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