Påverkan på elkvaliteten i Lidköpings distributionsnät vid ökad mikroproduktion
2017 (Swedish)Independent thesis Basic level (professional degree), 10 credits / 15 HE credits
Student thesisAlternative title
Impact on power quality in Lidköpings distribution network from increased micro production (English)
Abstract [sv]
Inom Lidkopings kommun har ett intresse for mikroproduktion i form av solcellsanlaggningar okat. Privatpersoner har borjat installera solcellsanlaggningar och kommunen har borjat lagga fram forslag till kommunala mal for en okad elproduktion fran solenergi. En studie ska utforas for att undersoka hur en okad mikroproduktion kan komma att paverka elnatets elkvalitet och hur detta kan forebyggas. Undersokningen bestar av elkvalitetsmatningar, simuleringar och berakningar. Da spanningsvariationer forvantas uppkomma fran den okade mikroproduktionen undersoks en vald komponent med automatisk spanningsreglering for att forebygga otillatna spanningsnivaer.
Elkvalitetsmatningarna utfors under november manad pa tva matobjekt med installerade solcellsanlaggningar, en tatortsvilla och en landsbygdsgard. Matningarna anvands till att granska elkvaliteten. Rapporter genereras aven for jamforelse med gransvarden fran tillganglig europeisk standard. Simuleringarna utfors efter befintliga natstrukturer under Lidkoping elnats omradeskoncession. I ett enstaka fall skapas ett fiktivt nat for simulering. Behandlade
spanningsnivaer ar lagspannings- och mellanspanningsnat. Till grund for simuleringarnas konsumtions- och produktionseffekter anvands data fran befintliga solcellsanlaggningar, Lidkoping elnats dokumentation och material med generella varden. Berakningar utfors efter simulerade resultat for att rakna ut de totala spanningsvariationerna.
Ytterligare berakningar utfors pa hur en integration av regleringskomponenten kan paverka dessa totala spanningsvariationer. Dessa jamfors sedan med gransvarden fran EI och Energiforetagen Sverige. Matningarna pavisar en viss okning i fasspanningarnas overtonshalt samt en okning i fasspanningarnas effektivvarde under produktion. De genererade rapporterna resulterar inte i nagra otillatna varden enligt europeisk standard. Simuleringarnas beraknade resultat overstiger inte Energimarknadsinspektionens tillatna granser. Daremot overstiger det svagare natet pa landsbygd Energiforetagen Sveriges rekommenderade gransvarden om mellanspannings-natets spanningsvariationer bedoms vara sma. Efter berakningar med en integrerad spanningsregleringskomponent overskrider inte spanningsnivan dessa rekommenderade gransvarden. Darfor ar inte Lidkoping elnat skyldiga till att atgarda spanningsvariationerna men bor gora det enligt rekommendation om spanningsvariationerna i mellanspannings-natet bedoms vara sma.
Abstract [en]
The community of Lidkoping have gained an increased interest for micro production in the form of solar energy. Citizens have started to install photovoltaic plants in their homes and the community has proposed goals towards an increased solar production of electricity. A study is demanded to investigate how an increased micro production can affect the power quality and how this can be prevented. The study includes measurements of the power quality, simulations and calculations. Due to the expected voltage fluctuations the increased micro production will contribute, a component of automatic voltage regulation is studied in order to prevent illicit levels of voltage.
The power quality measurements are performed during November on two measuring objects with installed photovoltaic plants, one urban household and one rural farm. The measurements are used to study the power quality. Reports are also generated for comparison of the limits found in an available European standard. The simulations are based on the existing structures of the power grid within the concession of Lidkoping elnat. In a single case a fictitious grid is made for simulation. Treated voltage levels are low voltage and medium voltage. The values of production and consumption are based on data acquired from the existing photovoltaic plants, documentation from Lidkoping elnat and material consisting general values. Calculations are based on the result of the simulations in order to calculate the total voltage fluctuations. Additional calculations are made to study how the integration of a regulating component can affect these total voltage fluctuations.
The measurements shows increased levels of harmonics and RMS-values in the voltage during production. The generated reports shows no illicit values of power quality according to European standard. The calculated result of the simulations do not exceed the allowed values of Swedish Energy Markets Inspectorate. However does the rural grid exceed recommended values of Swedenergy if the voltage fluctuations are deemed small. The result of the calculations including an integrated component of voltage regulation don´t exceed these recommended values. Therefor isn´t Lidkoping elnat obliged to regulate the voltage fluctuations but should if the voltage fluctuation of the medium voltage grid is deemed small.
Place, publisher, year, edition, pages
2017. , p. 46
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
URN: urn:nbn:se:hv:diva-10730Local ID: EXM505OAI: oai:DiVA.org:hv-10730DiVA, id: diva2:1075473
Subject / course
Electrotechnology
Educational program
Elkraft
Supervisors
Examiners
2017-02-202017-02-202017-02-20Bibliographically approved