Projektet utförs på IKKAB, ett elkonsultbolag som växte fram i slutet av 2006. I projektet utförs en projektering av en friledning med belagd ledare på 24 kV där syftet är att skapa förståelse för luftledningar och dess ingående komponenter. En litteraturstudie genomförs i rapporten där viktig kunskap inom bland annat isolation och överspänningar sammanställs. Viktiga komponenter beskrivs mer i detalj tillsammans med riktlinjer för utförande nära allmän väg. Profiler tas fram för mark och stolplinje utifrån lägesdata och utgör grunden för att ta fram det material som erfordras till stolplinjen. Detta material sammanställs för den färdiga projekteringen och presenteras i rapporten tillsammans med de framtagna profilerna. Arbetet har resulterat i en färdig mall för luftledningskonstruktioner och från denna presenteras ett utdrag av tre viktiga konstruktioner av stolpar för en överblick över materialet. Det finns inte enbart ett sätt att utforma en mall för luftledningskonstruktioner varav stora krav på både erfarenhet och jämförelse av material har uppkommit genom projektets gång. Genom samråd har ett gott resultat uppnåtts där utrymme finns att utveckla och forma mallen även utefter framtida behov när den tillämpas i skarpa projekt. Denna mall kommer att utgöra ett underlag för beredare på IKKAB vid arbete med luftledningar och efter projektets slutförande skall materialsammanställningen infogas i IKKABs programvara för beredningar. / The project is performed at IKKAB, a consulting company specialized in electricity that emerged at the end of 2006. In the project an overhead power line of 24 kV is planned where the purpose is to gather understanding for power lines and its components. A literature study is performed where important knowledge is compiled for isolation and overvoltages among other things. Important components are described in more detail together with the guidelines regarding implementation near public roads. Profiles are created based on location data for the ground and power line and forms the foundation for the collection of materials required in the power line. A list for the material included in the power line along with profiles are presented in the report. The result of this work is a complete template for constructions in overhead power lines, and from this template an excerpt is presented for three essential constructions to give an overview of the material. There is not one single way to design a template for overhead power lines, therefore great demands on both experience and comparisons regarding choice of materials emerged throughout the project. Through consultation a satisfying result has been achieved where room for future demands in shaping and development of the template is accounted for. This template will form a support for workers at IKKAB in projects including overhead power lines and will be inserted into IKKAB’s software for planning projects.

Denna rapport undersöker hur regionnät i stort är uppbyggt för att få en förståelse för strukturen i näten. Rapporten innefattar en kort teoribeskrivning om vad åska är samt åsknedslagens inverkan på näten. En geografisk undersökning av regionnätens luftledningars placering i förhållande till åsknedslagsfrekvens och åskstörningsfrekvens har analyserats i rapporten. Detta arbete vill Vattenfall ha gjort för att idag tar de inte åsknedslagfrekvensens geografiska lokalisering i beaktande vid nybyggnation eller modernisering av elnäten. Det kan ses tendenser till att det blir en förändrad bild över hur åskan slår ner i Sverige, det har kopplats till klimatförändringar som sker runtom i världen. Åskstörningar i elnäten är idag en viktigare faktor, då samhället har blivit mer beroende av en störningsfri leverans av el. Detta visar sig främst inom industrisektorn, men även i andra sektorer som till exempel serverhallar. Det har även blivit hårdare krav från Energimarknadsinspektionen sedan avregleringen 1996. I arbetet används en anläggningsdatabas för att hitta placering och störningshistorik inom Regionnät. Även SMHI:s kartor och data används för att ta fram åskhistoriken i Sverige. Resultatet presenteras med framförallt grafer över de olika områdena som hanteras. Vidare studier som föreslås är att undersöka vilka lösningar som är ekonomiska då det finns många olika lösningar med olika kostnader och hur bra de motverkar åskans inverkan. / This report examines how regional grid are built to gain an understanding of the grid’s structure. The report includes a brief theoretical description of what thunder is and the impact on the grid a thunderbolt has. A geographical study of the location of the regional grid's overhead lines in relation to the lightning strike frequency and lightning interference frequency. Vattenfall wants this work done because today they do not consider the geographical location of the lightning strike frequency in new construction or modernization of the electricity grid. There is a tendency to see a changed view of how the thunderstorm is striking in Sweden, it has been linked to climate change that is happening around the world. Lightning interference have also become more critical in the electricity grid, as society has become more dependent on an uninterrupted supply of electricity. This is mainly in the industrial sector, but also in other sectors such as server halls. There have also been stricter demands from the Energimarknadsinspektionen since the deregulation in 1996. In the work, a program was used to find location and disturbance history within the regional grid. SMHI's maps and data are also used to collect the location of thunderstorm history in Sweden. The results are presented with graphs of the different areas being managed. Further studies that are proposed are to investigate which solutions are economical as there are many different solutions with different costs and how well they counteract the impact of thunder.

The digitalization of our community, robotization of our industry and electrification of our transports leads to an increasing demand of electric power, which relies on a strong and reliable grid. In order to continuously be able to deliver stable and qualitative electric power all over Sweden the grid needs to be expanded. To safely expand the grid, several laws, regulations and safety precautions needs to be followed and one of them applies to the magnetic field from high voltage power lines. This Master thesis aims to show two different ways of calculating the magnetic field from high voltage power lines. The first way is to take the transmission line catenary in account and the other is to approximate a straight line and show the magnetic field extension. It also aims to show how the field looks close to transmission poles, both straight and with angles, in order to find out if that changes the field outcome. Both ways of calculating the field shows the same magnetic field magnitude below the point where the catenary hangs down the most. With the catenary taken into account, the magnetic field strength is lower than with the approximation with straight line, and shows the real field extension from the powerline. Using the straight line approximation, the magnetic field is higher and constant below the whole power line. As both ways of calculating takes a high amount of time, the one that gives the real field extension is recommended to use for real life application.

This report contains the influencing factors in high voltage overhead power lines and how these factors are controlled and calculated. A program has been produced so that a projector easily can insert the overhead line supports’ and lines’ parameters in the program. The program calculates and controls the distances required within the support and if the construction is requisite for the chosen system voltage and support site. The program controls for instance the distance between the phases, between phase line and top line, guy wires, cross arm and poles. The program creates a output file which is a summary of the support and warns if the required distances within the support is not fulfilled. The supports that are most exposed to forces are angular supports (where the overhead power line changes direction) and end supports (where the overhead line ends).

Trefas högspänd växelströmsöverföring via luftledningar medför överföringsförluster och magnetiska störfält. Fasledarnas inbördes avstånd och konfiguration påverkar dessa fenomen. Genom att låta fasledarna successivt byta plats (transponeras) mellan varje stolpe/torn skulle effekterna av fenomenen potentiellt kunna minskas. En slinga bestående av en ledare samt återledare av rostfritt stål fastsydd i ett nylonband tillverkades samt geometriska och elektromagnetiska modelleleringar av en successivt transponerad luftledning utfördes. Utifrån den geometriska modelleringen och med ett existerande △-konfigurerat trefassystem som förlaga kontruerades en ekvivalent trefasmodell i miniatyr. Experiment utfördes på slingan och på luftledningsmodellen. Späningsfallen i en krets med en rak respektive skruvad slinga mättes med oscilloskop. Magnetfälten kring den raka och de transponerade modellerna mättes med en mätspole. Experimenten gav att induktansen ökade med graden av successiv transponering medan kapacitansen minskade. Överlag syntes störfälten minska vid transponering. En dylikt transponerad ledningstyp skulle kunna vara ett alternativ till en rak när en minskning av magnetfälten är önskad. Magnetfältsmätningarnas tillförlitlighet begränsades av fasasymmetri i mätuppställningen och avvikelser i positioneringen av mätspolen mellan mätserierna. Därmed krävs ytterligare experiment för att exakt fastställa effekterna av successiv transponering. / Three phase high voltage alternating current overhead line systems are associated with losses along the lines and disrupting magnetic fields surrounding the conductors. These negative effects could possibly be combated by twisting the conductors. The twist was achieved by gradually shifting the conductors positions (transposition) over each span of transmission line. A test circuit with a stainless steel wire was made. Geometric and electromagnetic modelling of a successively transposed power line was performed. A miniature three phase overhead line model was constructed.. The model was based on the results from the geometric modeling and data from a real △-configured power system application. Experiments were made with both the steel wire circuit and the overhead line model. Voltage drops in the circuit with a straight - and twisted wire was measured with an oscilloscope. Magnetic flux around the overhead line models were measured with a solenoid. The results from the experiments showed that twisting the conductors resulted in an increase in inductance and a decrease in capacitance. Regarding the magnetic fields, indications of an overall decrease was observed with the twisted configurations compared to the straight. Twisted overhead lines could be viable when an overall decrease in magnetic field is needed. Due to uncertainties in the magnetic field measurements, more extensive experiments should be conducted in order to solidify the results of this work.

A general local powerline has implemented to mimic a lifelike powerline build around 1960s in thecountryside. Since reconstruction is needed a new projection is made of the area to improve the powerquality. The projection includes the old transmission lines will be replaced with underground powercables to make it weatherproof. The implication of underground power cables leads to smaller distancebetween the phases which generates greater capacitance. Due the increase will make the capacitivecurrents greater as well which affect the power quality for the costumers in the area. The projectionmust be adapted to the increase of earth fault currents which the capacitive currents contribute. The regeneration of the old and new power lines consists a sketch of terrain, merge of the powerconsumption, electrical fuses, line diagram, sizing transformers and right dimensions of cables. Calculations on capacitive fault current, voltage drop as well as neutral grounding reactor (a resistanceparallel with an inductor) was executed. Calculations of the powerline followed Swedish standard andthe neutral ground reactor after the norms of Swedish electrical industry. Regard to the projection, including underground cables, the capacitive fault currents increased with 46,75 times compared to transmission powerlines at 10 kV. Calculations of the neutral ground reactorresulted in 5,25 Henry for the inductor and 1154 Ohm for the resistor to compensate the gain. The conclusion is that weatherproofing the powerline at 10 kV leads to compensating otherwise the powerquality and selectivity will be affected. That result in a more expensive arrangement cost forunderground cables compared to transmission.

The thesis aims to examine the impact of climate change on line rating and to investigate the possibility of a potential increase of capacity of an overhead line. The line rating of an overhead line determines how much current can be transmitted in the line. The weather parameters which affect the line rating are ambient temperature, solar radiation, wind speed, and wind direction. If the line rating is adapted to weather conditions, it is important to be able to predict how the weather will change in the future. Therefore, the impact of climate change on weather parameters is investigated. The ambient temperature and solar radiation are expected to change between different scenarios. However, it is unclear how wind speed and wind direction will be affected. Climate scenarios are designed that take these findings into account. The results show that wind speed has, by a large margin from other weather parameters, the largest impact on the dynamic line rating. This is followed by the wind's angle of attack to the conductor, ambient temperature, and finally solar radiation. For the designed climate scenarios, the dynamic line rating is almost the same in each case, which means that the calculated change in ambient temperature and solar radiation has no significant effect on the line rating. To further increase the capacity of the overhead line, the line could be upgraded with a conductor with a larger cross-sectional area.