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Automated fault location plays a key role in improving the reliability of modern power grids—it helps to reduce the power outage time and the number of affected customers. Earth faults in isolated systems are among the fault types that are difficult to detect and locate with a reasonable accuracy, and there has therefore not been a well-established method for detecting and locating such faults in isolated systems. This paper presents two novel current-based methods for locating earth faults in unearthed closed-ring MV networks. The methods are based on the utilisation of sequence components of standard current and voltage measurement at a primary substation and they do not require new devices or measurements in the field. Both methods are tested with a simulation of a network based on data provided by a Norwegian network operator and their prediction performances were investigated considering different scenarios on fault resistance, load asymmetry and measurement errors. Both methods performed well and showed good accuracy. The simulation results are promising and strengthens the prospect of further testing of the methods in real networks and adoption of the methods for a real-world implementation.

Euclid Consortium: S. Contarini et al., The Euclid mission – with its spectroscopic galaxy survey covering a sky area over 15 000 deg2 in the redshift range 0.9, We acknowledge the grant ASI n.2018-23-HH.0. SC, FM and LM acknowledge the use of computational resources from the parallel computing cluster of the Open Physics Hub (https://site.unibo.it/openphysicshub/en) at the Physics and Astronomy Department in Bologna. GV is supported by Universitá degli Studi di Padova and in part by the project “Combining Cosmic Microwave Background and Large Scale Structure data: an Integrated Approach for Addressing Fundamental Questions in Cosmology”, funded by the MIUR Progetti di Rilevante Interesse Nazionale (PRIN) Bando 2017 – grant 2017YJYZAH. AP is supported by NASA ROSES grant 12-EUCLID12-0004, and NASA grant 15-WFIRST15-0008 to the Nancy Grace Roman Space Telescope Science Investigation Team “Cosmology with the High Latitude Survey”. NH is supported by the Excellence Cluster ORIGINS, which is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy – EXC-2094 – 390783311. MS acknowledges support by the P. E. Filén fellowship and a fellowship at the Swedish Collegium for Advanced Study (SCAS). LM acknowledges support from PRIN MIUR 2017 WSCC32 “Zooming into dark matter and proto-galaxies with massive lensing clusters”. AR acknowledges funding from Italian Ministry of Education, University and Research (MIUR) through the ‘Dipartimenti di eccellenza’ project Science of the Universe. He is supported in part by the project “Combining Cosmic Microwave Background and Large Scale Structure data: an Integrated Approach for Addressing Fundamental Questions in Cosmology”, funded by the MIUR Progetti di Rilevante Interesse Nazionale (PRIN) Bando 2017 – grant 2017YJYZAH We acknowledge use of the Python libraries NumPy (Harris et al. 2020), Matplotlib (Hunter 2007) and ChainConsumer (Hinton 2016). This work has made use of Cosmo-Hub (Carretero et al. 2017; Tallada et al. 2020). CosmoHub has been developed by the Port d’Informació Científica (PIC), maintained through a collaboration ofthe Institut de Física d’Altes Energies (IFAE) and the Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT) and the Institute of Space Sciences (CSIC & IEEC), and was partially funded by the “Plan Estatalde Investigación Científica y Técnica y de Innovación” program of the Spanish government. The Euclid Consortium acknowledges the European Space Agency and a number of agencies and institutes that have supported the development of Euclid, in particular the Academy of Finland, the Agenzia Spaziale Italiana, the Belgian Science Policy, the Canadian Euclid Consortium, the French Centre National d’Etudes Spatiales, the Deutsches Zentrum für Luft- und Raumfahrt, the Danish Space Research Institute, the Fundação para a Ciência e a Tecnologia, the Ministerio de Ciencia e Innovación, the National Aeronautics and Space Administration, the National Astronomical Observatory of Japan, the Netherlandse Onderzoekschool Voor Astronomie, the Norwegian Space Agency, the Romanian Space Agency, the State Secretariat for Education, Research and Innovation (SERI) at the Swiss Space Office (SSO), and the United Kingdom Space Agency.

The introduction of Information and Communications Technology (ICT) into conventional power grids has resulted in a digitalized smart grid, enabling a more efficient and robust operation. However, it can also lead to increased risk and new threats due to more complex systems and longer supply chains. Recent events indicate that the electrical power grid is an attractive target, promoting the need for well-prepared incident management processes that involve external vendors. This paper addresses this through the development of scenarios for collaborative preparedness exercises, and an investigation into which factors may contribute to making it easier to include vendors in preparedness exercises.

This paper reviews the capabilities of the conservative power theory (CPT) for active power filtering (APF) and power factor correction, specifically under distorted and asymmetric voltage regime. Both through simulation and experimental verification it is demonstrated how the CPT can selectively neutralize current non-idealities, under harsh voltage conditions. Thus, the experimental results confirm that the CPT framework provides means of achieving Fryze currents, with unity power factor, transporting real power at the minimum line current RMS value.

This paper explores the use of the conservative power theory for active shunt compensation, and provides experimental validation of reactive compensation and harmonic filtering. It is aimed to provide a more in-depth review of how the conservative power theory operates as a control algorithm for a shunt compensator. Also there is discussion on some of the challenges associated to practical implementation of active filters.

In five-long term field trials with reduced or no-tillage the grain yield decreased and the weed infestation increased compared to autumn or spring ploughing. Both stubble treatment with glyphosate and post-emergence weed control in the crop were necessary for sufficient weed control and to keep the yield at the same level as for the ploughed plots in these systems. Weather conditions influenced weed emergence and growth of weeds and cereals during the growing seasons, and thereby the yield depressing effect of the weeds.