Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Physics of Electrical Discharge Transitions in Air
KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.ORCID iD: 0000-0001-5378-701X
2017 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Electrical discharges with a variety of different forms (streamers, glow corona, leaders, etc.) broadly exist in nature and in industrial applications. Under certain conditions, one electrical discharge can be transformed into another form. This thesis is aimed to develop and use numerical simulation models in order to provide a better physical understanding of two of such transitions, namely the glow-to-streamer and the streamer-to-leader transitions in air.

In the first part, the thesis includes the two-dimensional simulation of the glow-to-streamer transition under a fast changing background electric field. The simulation is performed with a fluid model taking into account electrons. An efficient semi-Lagrangian algorithm is proposed to solve the convection-dominated continuity equations present in the model. The condition required for the glow-to-streamer transition is evaluated and discussed. In order to enable such simulations for configurations with large interelectrode gaps and long simulation times, an efficient simplified model for glow corona discharges and their transition into streamers is also proposed.

The second part of the thesis is dedicated to investigate the dynamics of the streamer-to-leader transition in long air gaps at atmospheric pressure. The transition is studied with a one-dimensional thermo-hydrodynamic model and a detailed kinetic scheme for N2/O2/H2O mixtures. In order to evaluate the effect of humidity, the kinetic scheme includes the most important reactions with the H2O molecule and its derivatives. The analysis includes the simulation of the corresponding streamer bursts, dark periods and aborted leaders that may occur prior to the inception of a stable leader. The comparison between the proposed model and the widely-used model of Gallimberti is also presented.

Abstract [sv]

Elektriska urladdningar av olika former (streamers (från engelska), glöd-korona, ledare, etc.) förekommer i stor utsträckning i naturen och i industriella applikationer. Under vissa förhållanden kan en elektrisk urladdning omvandlas till en annan form av elektrisk urladdning. Denna avhandling syftar till att utveckla och använda numeriska simuleringsmodeller för att ge en bättre fysikalisk förståelse av två sådana övergångar, nämligen glöd-till-streamer- och streamer-till-ledar-övergångar, i luft.

I den första delen, avhandlas en tvådimensionell simulering av glöd-till-streamer-övergången med ett hastigt föränderligt elektriskt fält i bakgrunden. Simuleringen utförs med en flödesmodell som tar hänsyn till elektronerna. En effektiv semi-Lagrangesk algoritm föreslås för att lösa de konvektionsdominerade kontinuitetsekvationerna i modellen. Vidare utvärderas och diskuteras förutsättningarna för glöd-till-streamer-övergången. För att möjliggöra sådana simuleringar i konfigurationer med stora elektrodavstånd och långa simuleringstider, föreslås också en effektiv och förenklad modell för glöd-korona-urladdningar samt deras övergång till streamers.

Den andra delen av avhandlingen är tillägnad att undersöka dynamiken i streamer-till-ledar-övergångar över långa avstånd i luft, under atmosfäriskt tryck. Övergången studeras med en endimensionell termohydrodynamisk modell och en detaljerad kinetisk modell för blandningar av N2/O2/H2O. För att utvärdera effekten av luftfuktighet, innefattar den kinetiska modellen de viktigaste reaktionerna med H2O-molekylen och dess derivat. Analysen innefattar simuleringen av motsvarande streamer-kedjor, mörka perioder och avbrutna ledare som kan förekomma före starten av en stabil ledare. En jämförelse mellan den föreslagna modellen och den allmänt använda modellen av Gallimberti presenteras också.

Place, publisher, year, edition, pages
KTH Royal Institute of Technology, 2017. , 52 p.
Series
TRITA-EE, ISSN 1653-5146 ; 2017:028
Keyword [en]
electrical discharges, transition, streamers, glow corona, leader discharges
Keyword [sv]
elektriska urladdningar, övergång, streamers, glöd-korona, ledarurladdningar
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Electrical Engineering
Identifiers
URN: urn:nbn:se:kth:diva-205401ISBN: 978-91-7729-348-4 (print)OAI: oai:DiVA.org:kth-205401DiVA: diva2:1088880
Public defence
2017-05-24, Kollegiesalen, Brinellvägen 8, Stockholm, 10:00 (English)
Opponent
Supervisors
Note

QC 20170418

Available from: 2017-04-18 Created: 2017-04-17 Last updated: 2017-04-18Bibliographically approved
List of papers
1. An Efficient Semi-Lagrangian Algorithm for Simulation of Corona Discharges: The Position-State Separation Method
Open this publication in new window or tab >>An Efficient Semi-Lagrangian Algorithm for Simulation of Corona Discharges: The Position-State Separation Method
2016 (English)In: IEEE Transactions on Plasma Science, ISSN 0093-3813, E-ISSN 1939-9375, Vol. 44, no 11, 1-10 p.Article in journal (Refereed) Published
Abstract [en]

An efficient algorithm without flux correction for simulation of corona discharges is proposed. The algorithm referred to as the position-state separation method (POSS) is used to solve convection-dominated continuity equations commonly present in corona discharges modelling. The proposed solution method combines an Eulerian scheme for the solution of the convective acceleration, the diffusion and the reaction subproblems, and a Lagrangian scheme for the solution of the linear convection subproblem. Several classical numerical experiments in different dimensions and coordinate systems are conducted to demonstrate the excellent performance of POSS regarding low computational cost, robustness, and high-resolution. It is shown that the time complexity of the method when dealing with the convection of charged particles increases linearly with the number of unknowns. For the simulation of corona discharges where local electric fields do not change strongly in time, the time step of POSS could be much larger than the Courant–Friedrichs–Lewy (CFL) time step. These special features enable POSS to have great potential in modeling of corona discharges in long interelectrode gaps and for long simulation times.

Place, publisher, year, edition, pages
IEEE Press, 2016
Keyword
Semi-Lagrangian method; simulation; corona discharges; convection-dominated
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering Fusion, Plasma and Space Physics
Research subject
Electrical Engineering
Identifiers
urn:nbn:se:kth:diva-193002 (URN)10.1109/TPS.2016.2609504 (DOI)000388795400001 ()2-s2.0-84991688609 (Scopus ID)
Note

QC 20160928

Available from: 2016-09-24 Created: 2016-09-24 Last updated: 2017-04-17Bibliographically approved
2. Application of the Position-State Separation Method to Simulate Streamer Discharges in Arbitrary Geometries
Open this publication in new window or tab >>Application of the Position-State Separation Method to Simulate Streamer Discharges in Arbitrary Geometries
2017 (English)In: IEEE Transactions on Plasma Science, ISSN 0093-3813, E-ISSN 1939-9375Article in journal (Refereed) Published
Abstract [en]

In this paper, we extended the recent work of Liu and Becerra to employ the position-state separation (POSS) method to simulate filamentary streamer discharges. POSS is a semi-Lagrangian method, which solves convection-dominated continuity equations without numerical flux correction. An improved interpolation strategy for POSS is here introduced to overcome the excessive numerical diffusion of the method when very small time step is used. Several benchmark tests in the literature are used to validate the improved method. Numerical experiments show that POSS is an accurate, efficient, and robust numerical method to simulate streamer discharges in arbitrary geometries when combined with finite-element method.

Place, publisher, year, edition, pages
IEEE Press, 2017
Keyword
streamer discharges., Arbitrary geometries, continuity equations, simulation
National Category
Engineering and Technology Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Electrical Engineering
Identifiers
urn:nbn:se:kth:diva-202744 (URN)10.1109/TPS.2017.2669330 (DOI)000399724600001 ()2-s2.0-85016504573 (Scopus ID)
Note

QC 20170314

Available from: 2017-03-04 Created: 2017-03-04 Last updated: 2017-06-02Bibliographically approved
3. On the transition from stable positive glow corona to streamers
Open this publication in new window or tab >>On the transition from stable positive glow corona to streamers
2016 (English)In: Journal of Physics D: Applied Physics, ISSN 0022-3727, E-ISSN 1361-6463, Vol. 49, no 22, 225202- p.Article in journal (Refereed) Published
Abstract [en]

A 2D numerical simulation of the transition from stable positive glow corona to streamers in coaxial cylindrical configuration is presented. The hydrodynamic model with several convection-dominated continuity equations together with Poisson equation are solved with consideration of the ionization layer. The transition from a stable positive glow corona produced under a DC voltage to streamers is investigated under a sudden change of the applied voltage. The critical rate of rise of voltage required for the transition from positive glow to streamer corona is evaluated with a voltage ramp. By introducing either physical or numerical instabilities into the model, streamers with filamentary structures are observed, which produce a sudden increase of the discharge current by more than two orders of magnitude. It is also found that the surface electric field of the corona-generating conductor deviates from the onset electric field, casting doubts about the validity of Kaptzov's approximation to evaluate the transition from stable glow to streamers.

Place, publisher, year, edition, pages
Institute of Physics (IOP), 2016
National Category
Electrical Engineering, Electronic Engineering, Information Engineering Fusion, Plasma and Space Physics
Research subject
Electrical Engineering
Identifiers
urn:nbn:se:kth:diva-186204 (URN)10.1088/0022-3727/49/22/225202 (DOI)000377410800010 ()2-s2.0-84971571485 (Scopus ID)
Note

QC 20160510

Available from: 2016-05-04 Created: 2016-05-04 Last updated: 2017-05-04Bibliographically approved
4. An efficient model to simulate stable glow corona discharges and their transition into streamers
Open this publication in new window or tab >>An efficient model to simulate stable glow corona discharges and their transition into streamers
2017 (English)In: Journal of Physics D: Applied Physics, ISSN 0022-3727, E-ISSN 1361-6463, Vol. 50, no 10, 105204- p.Article in journal (Refereed) Published
Abstract [en]

A computationally efficient model to evaluate stable glow corona discharges and their transition into streamers is proposed. The simplified physical model referred to as the SPM is based on the classic hydrodynamic model of charge particles and a quasi-steady state approximation for electrons. The solution follows a two-step segregated procedure, which solves sequentially the stationary continuity equation for electrons and then time-dependent continuity equations for ions. The validity of using the SPM to simulate glow corona discharges and their transition into streamers is demonstrated by performing comparisons with a fully coupled physical model (FPM) and with experimental data available in the literature for air under atmospheric conditions. It is shown that the SPM can obtain estimates similar to those calculated with the FPM and those measured in experiments but using significantly less computation time. Since the proposed model simulates efficiently the ionization layer without prior knowledge of the surface electric field or the discharge current, it is a computationally efficient alternative to calculations of glow corona discharges based on Kaptzov's approximation (KAM). The model can also be employed to efficiently calculate the conditions for the transition of glow corona into streamers, overcoming the limitations of KAM to provide such estimates.

Place, publisher, year, edition, pages
Institute of Physics (IOP), 2017
Keyword
efficient model, glow-to-streamer, transition, large scales
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Electrical Engineering
Identifiers
urn:nbn:se:kth:diva-201635 (URN)10.1088/1361-6463/aa5a34 (DOI)000401725300004 ()2-s2.0-85014366436 (Scopus ID)
Funder
StandUp
Note

QC 20170215

Available from: 2017-02-11 Created: 2017-02-11 Last updated: 2017-06-13Bibliographically approved
5. Gas heating dynamics during leader inception in long air gaps at atmospheric pressure
Open this publication in new window or tab >>Gas heating dynamics during leader inception in long air gaps at atmospheric pressure
2017 (English)In: Journal of Physics D: Applied Physics, ISSN 0022-3727, E-ISSN 1361-6463, Vol. 50, no 34, 345202Article in journal (Refereed) Published
Abstract [en]

The inception of leader discharges in long air gaps at atmospheric pressure is simulated with a thermo-hydrodynamic model and a detailed kinetic scheme for N2/O2/H2O mixtures. In order to investigate the effect of humidity, the kinetic scheme includes the most important reactions with the H2O molecule and its derivatives, resulting in a scheme with 45 species and 192 chemical reactions. The heating of a thin plasma channel in front of an anode electrode during the streamer to leader transition is evaluated with a detailed 1D radial model. The analysis includes the simulation of the corresponding streamer bursts, dark periods and aborted leaders that may occur prior to the inception of a propagating leader discharge. The simulations are performed using the time-varying discharge current in two laboratory discharge events of positive polarity reported in the literature as input. Excellent agreement between the simulated and the experimental time variation of the thermal radius for a 1m rod-plate air gap discharge event reported in the literature has been found. The role of different energy transfer and loss mechanisms prior to the inception of a stable leader is also discussed. It is found that although a small percentage of water molecules can accelerate the vibrational-translational relaxation to some extent, this effect leads to a negligible temperature increase during the streamer-to-leader transition. It is also found that the gas temperature should significantly exceed 2000 K for the transition to lead to the inception of a propagating leader. Otherwise, the strong convection loss produced by the gas expansion during the transition causes a drop in the translational temperature below 2000 K, aborting the incepted leader. Furthermore, it is shown that the assumptions used by the widely-used model of Gallimberti do not hold when evaluating the streamer-to-leader transition.

Place, publisher, year, edition, pages
Institute of Physics (IOP), 2017
Keyword
streamer-to-leader transition, kinetic model, streamer corona, leader discharge, humidity effect
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Electrical Engineering
Identifiers
urn:nbn:se:kth:diva-204632 (URN)10.1088/1361-6463/aa7c71 (DOI)000407003000001 ()2-s2.0-85027250129 (Scopus ID)
Note

QC 20170807

Available from: 2017-03-30 Created: 2017-03-30 Last updated: 2017-08-25Bibliographically approved
6. Two-dimensional simulation on the glow to streamer transition from horizontal conductors
Open this publication in new window or tab >>Two-dimensional simulation on the glow to streamer transition from horizontal conductors
2014 (English)Conference paper, Published paper (Refereed)
Abstract [en]

It has been recently suggested that glow corona generated during thunderstorms could have an important role in the initiation of streamers and upward connecting leaders from power transmission lines. In order to further investigate this, a two-dimensional evaluation of the glow corona generation is here reported, which takes into account the non-equilibrium ionization layer around the conductors. The critical change rate of the background electric field required for the transition from glow corona to streamer initiation is obtained. A numerical strategy to evaluate the glow corona to streamers transition for large gaps and irregular geometries is proposed and validated. A four-bundled conductor is also studied and results showed that when evaluating the critical rate of rise of the background electric field for a bundle conductor during thunderstorms, it could be viewed as a single conductor with the equivalent geometric mean radius of the wire configuration. Last, a study case is performed to estimate the effect of the glow corona on the streamer inception from UHV transmission lines during thunderstorms.

Series
2014 International Conference on Lightning Protection, ICLP 2014, 6973247
Keyword
lightning, glow corona; streamer inception; thunderstorm; two-dimensional simulation; ionization layer; UHV transmission lines
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Electrical Engineering
Identifiers
urn:nbn:se:kth:diva-166302 (URN)10.1109/ICLP.2014.6973247 (DOI)000358572100165 ()2-s2.0-84919822050 (Scopus ID)978-147993544-4 (ISBN)
Conference
2014 International Conference on Lightning Protection (ICLP)
Funder
StandUp
Note

QC 20150623

Available from: 2015-05-07 Created: 2015-05-07 Last updated: 2017-04-17Bibliographically approved
7. Two-dimensional Simulation on the Glow to Streamer Transition from Lightning Rods
Open this publication in new window or tab >>Two-dimensional Simulation on the Glow to Streamer Transition from Lightning Rods
2015 (English)Conference paper, Published paper (Refereed)
Abstract [en]

In the past twenty years, there has been a growing concern regarding the effect of space charge produced by glow corona on lightning attachment. Several studies have been reported in the literature to evaluate the generation and drift of space charge generated by glow corona from the top of high grounded objects under thunderstorm conditions, using one (1D) or two (2D) dimensional simulations. Unfortunately, the actual transition from glow corona to streamers cannot be numerically evaluated in these studies since the ionization layer was ignored. Thus, a fully 2D detailed evaluation of the glow corona to streamer transition in air is reported, which considers the non-equilibrium ionization layer around a scaled lightning rod. The transition criterion is obtained by changing the applied voltage with different rise rates (dV/dt) after a stable glow corona is formed. The discharge currents as well as the distributions of positive ions, electrons and electric field during the transition of glow corona to streamers are presented. Based on the simulation results, a case study regarding a real lighting rod under thunderstorms is performed. The analysis indicates that streamers can be incepted in the presence of glow corona from both the tip and body of lightning rods under the influence of distant downward stepped leaders.

Place, publisher, year, edition, pages
IEEE conference proceedings, 2015
Keyword
lightning rod, glow corona, streamer transition, thunderstorm, two-dimensional simulation, ionization layer
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Electrical Engineering
Identifiers
urn:nbn:se:kth:diva-168317 (URN)10.1109/SIPDA.2015.7339289 (DOI)000382966700067 ()2-s2.0-84962291996 (Scopus ID)978-1-4799-8753-5 (ISBN)
Conference
2015 International Symposium on Lightning Protection (XIII SIPDA)
Funder
StandUp
Note

QC 20160214

Available from: 2015-06-01 Created: 2015-06-01 Last updated: 2017-04-17Bibliographically approved

Open Access in DiVA

fulltext(1326 kB)141 downloads
File information
File name FULLTEXT01.pdfFile size 1326 kBChecksum SHA-512
c4960f358b95b459b39d26043eb3c35414359d30b13e3b5afd66d56c22bce86b9393584d14773d3f7df96232a21344d872b1d17b339154e591b4a69c8814b1b1
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Liu, Lipeng
By organisation
Electromagnetic Engineering
Electrical Engineering, Electronic Engineering, Information Engineering

Search outside of DiVA

GoogleGoogle Scholar
Total: 141 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 855 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf