In the past decade, inverter-integrated energy sources have experienced rapid growth, which leads to operating challenges associated with reduced system inertia and intermittent power generation, which can cause instability and performance issues of the power system. Improved control schemes for inverters are necessary to ensure the stability and resilience of the power system. Grid-forming inverters dampen frequency fluctuations in the power system, while grid-following inverters can aggravate frequency problems with increased penetration. This paper aims at reviewing the role of grid-forming inverters in the power system, including their topology, control strategies, challenges, sizing, and location. In order to facilitate continued research in this field, a comprehensive literature review and classification of the studies are conducted, followed by research gaps and suggestions for future studies.

Power fluctuations induced by wave energy converters (WECs) may reflect negative impact on the power quality of the power grid. Assessing their impact is an important step to ensure the grid compliance level of the energy park. The IEC 61000-4-15 standard classifies the allowable disturbances in the grid. This study analysed and assessed the grid impact in terms of flicker, harmonic distortion and voltage variations. The assessments were performed without energy storage and compared when using the energy storage. A single WEC is emulated as an irregular power output of a real WEC using a combined model of power take-off in the Simulink model. Time series based on data obtained in earlier offshore experiments, conducted at the Lysekil research site in Sweden, is used to emulate a wave energy park (WEP) power in a land-based test rig in real-time power hardware-in-theloop simulations. A total of three and ten WECs are emulated by introducing a time delay in the time series to investigate the grid impact in each layout. Flicker emissions, voltage variations, individual and total harmonics of the voltage at the connection point in each layout are studied and compared with the limits to be grid compliant for layouts of the WEP. In addition, voltage and current harmonics for the single WEC and individual harmonics in each phase of the voltage are measured and analysed to assess the compliance level of the WEP.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

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Tiedolla johtamisen tieto, tietäminen ja tiedonkäyttö ovat jääneet vähäisemmälle huomiolle, ja haluankin tutkielmallani lisätä ymmärrystä näistä tiedolla johtamisen osa-alueista.Matkailu mahdollistaa kohtaamiset erilaisten ihmisten sekä kumppanilajien kanssa. Eri toimijoiden tietämisen tavat voivat poiketa merkittävästi toisistaan. (Rantala ym., 2019, s. 4.) Matkailun eri sidosryhmien intressien yhteensovittamisen vuoksi erilaisten tietojärjestelmien integrointi matkailun johtamiseen on tärkeää. Tutkimusta paikallis-ja alkuperäiskansatiedon integroimisesta osaksi matkailun johtamista on kansainvälisesti tehty jonkin verran (esim. Butler & Menzies, 2007;Prasetyo, Carr & Filep, 2020), mutta Suomessa aihetta ei juuri ole tutkittu. Analysoin kandidaatin tutkielmassani Utsjoen (sme. Ohcejohka) kunnan matkailun strategisten dokumenttien -Utsjoen matkailun kehittämisohjelma ja maankäyttösuunnitelma (Utsjoen kunta, 2020) ja Utsjoen matkailun vastuullisuus-ja vähähiilisyysohjelman raportti (Utsjoen kunta, 2021) -tiedon tyyppejä sekä tiedonkäytön tapoja. Utsjoki on luovan tiedolla johtamisen näkökulmasta kiinnostava, sillä saamelaisten kotiseutualueella länsimainen tieto kohtaa alkuperäiskansatiedon. Kysyn tutkielmassani,