Endre søk
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Stochastic Assessment of Voltage Unbalance due to Single-Phase-Connected Solar Power
Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
Technische Universität Dresden.
Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.ORCID-id: 0000-0002-4004-0352
Institute of Electrical Power Systems and High Voltage Engineering, Technische Universitaet Dresden, Technical University Dresden, Dresden University of Technology.
Vise andre og tillknytning
Rekke forfattare: 52017 (engelsk)Inngår i: IEEE Transactions on Power Delivery, ISSN 0885-8977, E-ISSN 1937-4208, Vol. 32, nr 2, s. 852-861, artikkel-id 7488998Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

A stochastic method is presented in this paper to estimate the future voltage unbalance in a low-voltage distribution network with high-penetration of single-phase photovoltaic inverters (PVIs). Location and phase allocation of the PVIs are considered as input parameters for the stochastic simulation. The method has been applied to three different low-voltage networks: two in Sweden and one in Germany. In the Swedish networks, for 6-kW single-phase PVIs, it is likely that the contribution from single-phase photovoltaic inverters to the voltage unbalance exceeds 1%. The 2% value is unlikely to be exceeded. In the German network, for 4.6-kW single-phase PVIs the voltage unbalance is between 1.35% and 2.62%.The risk of high voltage unbalance can be reduced by a combination of controlled distribution over the phases and reduction of the maximum size for a single-phase PVI.

sted, utgiver, år, opplag, sider
IEEE, 2017. Vol. 32, nr 2, s. 852-861, artikkel-id 7488998
HSV kategori
Forskningsprogram
Elkraftteknik
Identifikatorer
URN: urn:nbn:se:ltu:diva-7911DOI: 10.1109/TPWRD.2016.2579680ISI: 000398907100029Scopus ID: 2-s2.0-85017651944Lokal ID: 65608cd0-3d7c-42f3-a987-7b5aa293d825OAI: oai:DiVA.org:ltu-7911DiVA, id: diva2:980801
Merknad

Validerad; 2017; Nivå 2; 2017-03-29 (andbra)

Tilgjengelig fra: 2016-09-29 Laget: 2016-09-29 Sist oppdatert: 2019-02-07bibliografisk kontrollert
Inngår i avhandling
1. On Transfer Functions for Power Quality Studies in Wind Power and Solar PV Plants
Åpne denne publikasjonen i ny fane eller vindu >>On Transfer Functions for Power Quality Studies in Wind Power and Solar PV Plants
2019 (engelsk)Doktoravhandling, med artikler (Annet vitenskapelig)
Alternativ tittel[sv]
Överföringsfunktioner förElkvalitetstudier i vindkraft- och Solcellsanläggningar
Abstract [en]

As part of the decarbonisation of the energy system, wind and solar power are expected to play an important role. However, together with their growth, new challenges appear in the electric power system; this requires further research, development, and often studies before connection is possible. Two of those challenges, both impacts on the quality of power, are the subject of this dissertation: harmonic distortion and voltage unbalance.

The growing use of solar power for electricity generation, especially in distribution systems, will result in increased voltage unbalance due to single-phase photovoltaic inverters (PVIs). Regulation on power quality and potential impact on other equipment, place a limit to the number of PVIs that can be connected to the system, the so-called “hosting capacity”. To include different uncertainties in the planning stage, a stochastic method based on the transfer-impedance matrix is proposed for quantifying this hosting capacity, with respect to voltage unbalance. The method has been illustrated by applying it to two typical Swedish low-voltage networks.

Wind power plants (WPPs) consist of a collection grid and a number of wind turbines. These are known to be a harmonic source as power electronic devices are used to connect them to the power system. Earlier studies have shown that the actual emission at harmonic frequencies is low, but that the main issue is related to the spread of harmonics through the collection grid, especially the role of resonances. Regulation setting emission limits and the potential adverse impact of harmonics on equipment make that studies are needed to predict harmonic voltages and currents in and around a WPP. These studies are based on measurements performed on individual turbines under certain operating conditions. The main issue related to this determination is distinguishing the emission originating within the WPP (primary emission) from the emission originating elsewhere (secondary emission). A critical review has been performed on methods used for harmonic emission determination (i.e. distinguishing between primary and secondary emission) in WPPs. It was concluded that this determination cannot be solved without making assumptions. Transfers functions are independent of the emission from the individual turbines and can be obtained with less assumptions. These transfer functions have been used to estimate the spread of harmonics through a WPP and towards the public grid. Transfer functions were shown to be a suitable tool to quantify amplifications due to resonances and identify which harmonic orders can be an issue.

Furthermore, information on the different transfer functions allows the selection of proper mitigation methods. This application of transfer functions has been illustrated for a specific advanced mitigation method: the use of inverter control techniques to emulate a “virtual resistor”. In this way it is possible to damp resonances without increasing fundamental-frequency losses.

The ultimate aim of harmonic studies is to avoid interference between the grid and equipment connected to it, in this case between the power-electronics in the wind turbine and other equipment. However, these studies rarely address actual cases of interference, instead of this, measured or calculated harmonic voltages and/or currents are compared with limits set in regulations. These and regulations differ strongly between countries and even between individual network operators. A comparative study of regulatory methods has been performed presenting their advantages and disadvantages from the viewpoint of the network operator and from the viewpoint of the owner or operator of the WPP.

sted, utgiver, år, opplag, sider
Luleå: Luleå University of Technology, 2019
Serie
Doctoral thesis / Luleå University of Technology 1 jan 1997 → …, ISSN 1402-1544
HSV kategori
Forskningsprogram
Elkraftteknik
Identifikatorer
urn:nbn:se:ltu:diva-71826 (URN)978-91-7790-278-2 (ISBN)978-91-7790-279-9 (ISBN)
Disputas
2019-02-15, A193, Hörsal A, Skellefteå, 10:00 (engelsk)
Opponent
Veileder
Tilgjengelig fra: 2018-11-30 Laget: 2018-11-29 Sist oppdatert: 2019-03-04bibliografisk kontrollert

Open Access i DiVA

Fulltekst mangler i DiVA

Andre lenker

Forlagets fulltekstScopus

Personposter BETA

Schwanz, DaphneRönnberg, SarahBollen, Math

Søk i DiVA

Av forfatter/redaktør
Schwanz, DaphneRönnberg, SarahBollen, Math
Av organisasjonen
I samme tidsskrift
IEEE Transactions on Power Delivery

Søk utenfor DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric

doi
urn-nbn
Totalt: 330 treff
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf