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  • 101.
    Bollen, Math
    et al.
    STRI - Sweden.
    Stephens, Mark
    EPRI - USA.
    Djokic, Sasa
    University of Edinburgh.
    Neumann, Robert
    Qualitrol.
    McEachern, Alex
    Power Standards Lab.
    Milanovic, Jovica V.
    University of Manchester.
    Gordon, José Romero
    Endesa, Sevilla.
    Brumsickle, Bill
    Soft Switching.
    Ethier, Gaetan
    Hydro-Québec Research’s Institute.
    Zavoda, Francisc
    IREQ.
    Stockman, Kurt
    Hogeschool West, Vlaanderen, Kortrijk.
    CIGRE/ CIRED/ UIE joint working group C4.110, Voltage dip immunity of equipment in installations: main contributions and conclusions2009Inngår i: CIRED 20th International Conference on Electricity Distribution: (CIRED 2009) ; Prague, Czech Republic, 8 - 11 June 2009, Red Hook, NY: Curran Associates, Inc., 2009, artikkel-id 0149Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents the results from the work of joint working group C4.110: a cooperation between CIGRE, CIRED and UIE. Its mandate period stretches from early 2006 through early 2009. The group has addressed several aspects of the immunity of, especially, industrial equipment against voltage dips. Quantifying or specifying equipment performance is part of the assessment or improvement of the voltage-dip ride-through of an industrial process.

  • 102.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Stephens, Mark
    EPRI.
    Stockman, K
    Djokic, S
    McEachern, A
    Gordon, J Romero
    Voltage dip immunity of equipment in installations2008Inngår i: Electrical Power Quality and Utilization, ISSN 1234-6799, Vol. 3, nr 2Artikkel i tidsskrift (Annet vitenskapelig)
  • 103.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Stephens, Mark
    EPRI.
    Stockman, K
    Djokic, S
    McEachern, A
    Gordon, J Romero
    Voltage dip immunity of equipment in installations: scope and status of the work, January 20082008Inngår i: CIGRE Sessions: CD ROM 2008 Session Papers, 2008Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents the status of the work, by April 2008, in C4.110, a joint working group by CIGRE, CIRED and UIE. Contributions of the working group are: a summary of voltage dip characteristics; a methodology to assess the performance of a complete installation and; recommendations for testing and immunity of equipment.

  • 104.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Stephens, Mark
    EPRI.
    Stockman, K
    Djokic, S
    McEachern, A
    Gordon, J Romero
    Voltage dip immunity of equipment in installations: scope and status of work2007Inngår i: CIGRE Symposium 2007: Transient phenomena in large electric power systems, Zagreb, Croatia 18-21 April 2007, 2007Konferansepaper (Fagfellevurdert)
  • 105.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Stephens, Mark
    Stockman, Kurt
    Djokic, Sasa
    McEachern, Alex
    Gordon, Jose Romero
    Imunidadede equipamentose instalaçõesa afundamentosde tensão2008Inngår i: Eletricidade Moderna, ISSN 0100-2104, s. 138-146Artikkel i tidsskrift (Annet vitenskapelig)
  • 106.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Stockman, K
    Hogeschool West, Vlaanderen, Kortrijk.
    Neumann, R
    Qualitrol, Belfast.
    Ethier, G
    Hydro-Québec Research’s Institute.
    Gordon, J Romero
    Endesa, Sevilla.
    Reussel, K van
    KU Leuven.
    Djokic, S. Z
    University of Edinburgh.
    Cundeva, S
    University Sts. Cyrill and Methodias, Skopje.
    Voltage dip immunity of equipment and installations: messages to stakeholders2012Inngår i: 15th International Conference on Harmonics and Quality of Power (ICHQP), IEEE Communications Society, 2012, s. 915-919Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents the messages to the stakeholders on voltage-dip immunity as extracted by UIE WG2 from CIGRE TB412 [1]. The paper summarizes the main recommendations from this technical brochure in the form of messages towards regulators, standard-setting-organizations, network operators, industrial customers, equipment manufacturers, and power quality monitor manufacturers, researchers.

  • 107.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Styvaktakis, Emmanouil
    Chalmers University of Technology, Department of Signals and Systems.
    Gu, Irene Yu- Hua
    Chalmers University of Technology, Department of Signals and Systems.
    Categorization and analysis of power system transients2005Inngår i: IEEE Transactions on Power Delivery, ISSN 0885-8977, E-ISSN 1937-4208, Vol. 20, nr 3, s. 2298-2306Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Power system transients are power-quality disturbances that can be harmful to electronic equipment. This paper contributes and provides some solutions to the following issues: 1) to introduce a new way to identify different categories of power system transients based on their underlying causes; 2) to propose a model and analysis tool for oscillatory transients, where emphasis is on finding phenomena and characteristics associated with the underlying causes of transients. A model-based approach, ESPRIT, is applied to a number of simulated voltage waveforms to extract the parameters of oscillatory transients, and the results may be used for identifying and understanding the causes of transients by correlating the major components in transients with the phenomena that may appear in different types of transients and some a priori knowledge of power system settings

  • 108.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Sun, Y.
    STRI AB.
    Ault, G.W.
    Institute for Energy and Environment, University of Strathclyde, Glasgow.
    Reliability of distribution networks with DER including intentional islanding2005Inngår i: International Conference on Future Power Systems, 2005 : [(FPS)]: 16 - 18 Nov. 2005, [Amsterdam, Netherlands], Piscataway, NJ: IEEE Communications Society, 2005Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents methods for calculating the reliability of distribution systems with distributed energy resources (DER). The impact of intentional islanding of the DER units on the reliability is studied in detail. Different levels of automation are considered, starting from the existing network and continuing with increasing levels of intelligence in the network. The role of the switching devices and of the restoration process is discussed in detail.

  • 109.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Trhulj, Jasmina
    AERS.
    Beyer, Yvonne
    NMA.
    Vailati, Riccardo
    AEEG.
    Styvaktakis, Emmanouil
    RAE.
    Friedl, Werner
    E-Control.
    A European benchmarking of voltage quality regulation2013Inngår i: 22nd International Conference and Exhibition on Electricity Distribution (CIRED 2013): Stockholm, Sweden, 10 - 13 June 2013, Red Hook, NY: Curran Associates, Inc., 2013, artikkel-id 350Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The Council of European Energy Regulators has been publishing Benchmarking Reports on the Quality of Electricity Supply since 2001. For the 2011 edition of the Benchmarking Report the 29 member countries of CEER were joined by the 9 NRAsfrom the Energy Community and the NRA from Switzerland. This paper contains the main results, findings and recommendations on voltage quality from the 2011 edition.

  • 110.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Verde, Paola
    University of Cassino.
    A framework for regulation of RMS voltage and short-duration under and overvoltages2008Inngår i: IEEE Transactions on Power Delivery, ISSN 0885-8977, E-ISSN 1937-4208, Vol. 23, nr 4, s. 2105-2112Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper proposes a general approach for voltage-quality regulation. The same framework covers voltage-amplitude variations, dips, and swells. The framework uses the difference between power-quality events and power-quality variations to introduce a "responsibility-sharing curve" distinguishing between normal operational voltage for which equipment should be immune and events that are subject to voltage-quality regulation. It is further proposed to use equipment immunity requirements as a basis for the responsibility-sharing curve.

  • 111.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Wallin, Lars
    Svenska Kraftnät.
    Ohnstad, Trond
    Statnett.
    Bertling, Lina
    Svenska Kraftnät.
    On operational risk assessment in transmission systems: weather impact and illustrative example2008Inngår i: Proceedings of the 10th International Conference on Probabilistic Methods Applied to Power Systems: PMAPS 2008, Piscataway, NJ: IEEE Communications Society, 2008, s. 218-223Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper discusses a number of aspects of operational-risk assessment of transmission systems. perational-risk assessment uses techniques developed from reliability analysis to predict the performance of the transmission system during a short period of time (several hours) starting from a well-defined operational state. The influence of weather parameters on the momentary failure rate and the operational risk is discussed in this paper as well. The operational-risk method is illustrated by means of a simple but realistic transmission-system model. The paper also discusses some of the applications for such methods in operation and planning of transmission systems.

  • 112.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Wang, Ying
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Voltage sag indices: future directions2015Inngår i: 2015 IEEE Power & Energy Society General Meeting: 26-30 July 2015, Denver CO, Piscataway, NJ: IEEE Communications Society, 2015Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Presents a collection of slides covering the following topics: voltage-dip characteristics; complex dip recording; transient segment; phase-angle jump; and information extraction.

  • 113.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Yang, Kai
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Harmonic aspects of wind power integration2013Inngår i: Journal of Modern Power Systems and Clean Energy, ISSN 2196-5625, E-ISSN 2196-5420, Vol. 1, nr 1, s. 14-21Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    This paper discusses a number of ways in which wind power installations can impact the harmonic levels in the power system. Wind turbines are an additional source of harmonic emission, especially when it concerns “non-characteristic harmonics.” Parallel resonances can amplify the emission from individual turbines. A mathematical model is developed to quantify this amplification. Series resonances can result in high currents, driven by the background voltage distortion in the transmission grid, flowing into the wind park. Weakening of the transmission grid will increase lower order harmonics but reduce higher order harmonics.

  • 114.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Yang, Kai
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Harmonics – another aspect of the interaction between wind-power installations and the grid2013Inngår i: 22nd International Conference and Exhibition on Electricity Distribution (CIRED 2013): Stockholm, Sweden, 10 - 13 June 2013, Red Hook, NY: Curran Associates, Inc., 2013, artikkel-id 408Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Wind parks are known as sources of harmonic distortion. The emission at the classical harmonic frequencies (low order non-triplen odd harmonics) is however low. Potential problems with connecting individual turbines and wind parks occur at non-standard frequencies, mainly due to harmonic resonances. Next to the harmonic currents driven by the emission from the turbines, studies should also consider the currents driven by the harmonic background distortion.

  • 115.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Yang, Kai
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Interharmonic currents from a Type-IV wind energy conversion system2017Inngår i: Electric power systems research, ISSN 0378-7796, E-ISSN 1873-2046, Vol. 143, s. 357-364Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents, for the first time, the verification of the classic model for the origin of interharmonic emission from a frequency converter, for a Type-IV wind turbine by using long-term measurements. Interharmonic variations in magnitude and in frequency are due to the difference between the generator-side and grid-side frequency of the full-power converter. The model verification consists of three parts: correlation between frequencies; relation between magnitude of interharmonics and active-power production, and relation between magnitudes of different interharmonics. The measurements are in agreement with the model predictions. The paper also introduces a novel graphical correlation method to extract information on interharmonics from long-term measurement series.

  • 116.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Yang, Yongtao
    STRI.
    Hassan, Fainan
    STRI.
    Integration of distributed generation in the power system: a power quality approach2008Inngår i: 2008 13th International Conference on Harmonics and Quality of Power: [ICHQP 2008] ; Wollongong, Australia, 28 September - 1 October 2008, Piscataway, NJ: IEEE Communications Society, 2008Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper gives an overview of the design and operation issues in distribution and transmission systems due to the integration of distributed generation. The hosting-capacity approach has been developed to obtain a quantitative measure on the amount of generation that can be connected without impairing the performance of the system. The hosting-capacity approach requires a set of well-defined performance indices together with acceptable limits.

  • 117.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Yao, Liangzhong
    Areva T and D, Technology Centre, Stafford.
    Rönnberg, Sarah
    Wahlberg, Mats
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik.
    Harmonic and interharmonic distortion due to a windpark2010Inngår i: IEEE Power and Energy Society General Meeting, Piscataway, NJ: IEEE Communications Society, 2010Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper discusses two aspects of the impact of windparks on the waveform distortion in the power system: emission and resonances. The paper gives a general overview of the emission and shows measurement results from a small but modern windpark connected to a 10-kV feeder and estimates the need for network strength to limit the resulting voltage distortion. The paper also gives a general overview of harmonic resonances associated with windparks and illustrates this by means of two numerical examples. Important conclusions from this paper are than harmonic resonances are more likely to be a concern that the emission from windparks, and that the interharmonic emission and the emission at non-characteristic harmonics are more prominent than with existing installations.

  • 118.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Zhong, J
    University of Hongkong.
    Lin, Y
    University of Hongkong.
    Performance indices and objectives for microgrids2009Inngår i: CIRED 20th International Conference on Electricity Distribution: (CIRED 2009) ; Prague, Czech Republic, 8 - 11 June 2009, Red Hook, NY: Curran Associates, Inc., 2009Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper gives recommendations to researchers and developers on how to evaluate the performance of microgrids during island operation. A microgrid is a small grid including distributed energy resources and loads that can operate independently in the case of emergency of distribution systems. During island operation, the performance requirements of microgrids could be different than those during interconnected operation. To quantify the performance of microgrids, we propose a number of performance indices for voltage quality and reliability.

  • 119.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Zhong, J.
    University of Hongkong.
    Samuelsson, O.
    Lund University.
    Björnstedt, J.
    Lund University.
    Performance indicators for microgrids during grid-connected and island operation2009Inngår i: 2009 IEEE Bucharest PowerTech Proceedings / [ed] Mircea Eremia, Piscataway, NJ: IEEE Communications Society, 2009Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper discusses methods for quantifying the performance of microgrids during island operation. Such methods are essential for comparing different designs and different control algorithms. Performance indicators and objectives are proposed for voltage-quality variations, for individual dips and interruptions, and for the reliability during island operation.

  • 120.
    Bollen, Math
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Zhong, Jin
    University of Hongkong.
    Zavoda, Francisc
    Hydro-Québec Research’s Institute.
    Meyer, Jan
    Technische Universität Dresden.
    McEachern, Alex
    Power Standards Labs, San Francisco.
    López, Felipe Córcoles
    Polytechnical University of Catalonia, Barcelona.
    Power quality aspects of smart grids2010Konferansepaper (Fagfellevurdert)
  • 121.
    Bracale, Antonio
    et al.
    Department for Technologies, University of Naples Parthenope.
    Carpinelli, Guido
    Department of Electrical Engineering, University of Naples Federico II.
    Gu, Irene
    Chalmers University of Technology, Department of Signals and Systems.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    A new joint sliding-window ESPRIT and DFT scheme for waveform distortion assessment in power systems2012Inngår i: Electric power systems research, ISSN 0378-7796, E-ISSN 1873-2046, Vol. 88, nr 7, s. 112-120Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper proposes a novel scheme that jointly employs a sliding-window ESPRIT and DFT for estimating harmonic and interharmonic components in power system disturbance data. In the proposed scheme, separate stages are utilized to estimate the voltage fundamental component, harmonics and interharmonics. This includes the estimation of the fundamental component from lowpass filtered data using a sliding-window ESPRIT, of harmonics from a sliding-window DFT with a synchronized window, and of interharmonics from the residuals by applying the sliding-window ESPRIT. Main advantages of the approach include high resolution and accuracy in parameter estimation and significantly reduced computational cost. Experiments and comparisons are made on both synthetic and measurement data. Results have shown the effectiveness and efficiency of the proposed scheme.

  • 122. Brekke, K
    et al.
    Schiavo, L Lo
    Villa, F
    Haber, A
    Kolessar, R
    Westergaard, T
    Esteves, J
    Falcäo, A
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Reti, G
    Monitoramento e regulamentação da qualidade da energia elétrica2010Inngår i: EM, s. 138-147Artikkel i tidsskrift (Annet vitenskapelig)
  • 123.
    Brekke, Karstein
    et al.
    NVE, Norway.
    Esteves, Jorge
    ERSE, Portugal.
    Bollen, Math
    STRI AB.
    Schiavo, Luca Lo
    AEEG, Italy.
    Villa, Ferruccio
    AEEG, Italy.
    Reti, Geza
    HEO, Hungary.
    Haber, Alfons
    E-Control, Austria.
    Falcão, Amanda
    ERSE, Portugal.
    Westergaard, Thomas
    EI.
    Kolessar, Remy
    EI.
    Monitoring of and regulations on quality of electricity supply in European countries2009Inngår i: CIRED 20th International Conference on Electricity Distribution: (CIRED 2009) ; Prague, Czech Republic, 8 - 11 June 2009, Red Hook, NY: Curran Associates, Inc., 2009, artikkel-id 0911Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The Council of European Energy Regulators (CEER) publishes regularly benchmarking reports on the electricity quality of supply (EQS) in its member countries. This paper introduces the content of and describes some of the important highlights from the content given in the 4th CEER Benchmarking Report on Quality of Electricity Supply [1], which is based on detailed information gathered from 27 European countries.

  • 124.
    Busatto, Tatiano
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Abid, Fahim
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Larsson, Anders
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Singh, Gaurav
    Department of Electrical and Computer Engineering, Clemson University.
    Interaction between Grid-Connected PV systems and LED Lamps: Directions for Further Research on Harmonics and Supraharmonics2016Inngår i: 2016 17th International Conference on Harmonics and Quality of Power, Piscataway, NJ, 2016, s. 193-197, artikkel-id 7783479Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper discusses different approaches to investigate the interaction through harmonics, interharmonics, supraharmonics, and light flicker, between photovoltaic (PV) inverters and LED lamps in low-voltage installations. Single grid-connected power generators and electronic loads like LED lamps can be easily characterized in terms of harmonics in a given range of frequency. This subject is relatively well understood, and specific standards for measuring and restricting emissions are already established to ensure a low probability of interference. However, when connected together, source and load exhibit behavior that requires further study and understanding. This work presents a discussion serving as a guide for future work on analysis of losses and other impacts of the disturbances regarding this specific load and source interaction. The following are taken into account: the nonlinearity of LED loads and PV converters; the technologies and methods used in control; and the changes in power flow caused by load and power production variations

  • 125.
    Busatto, Tatiano
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Larsson, Anders
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Rönnberg, Sarah
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Including Uncertainties from Customer Connections in Calculating Low-Voltage Harmonic Impedance2019Inngår i: IEEE Transactions on Power Delivery, ISSN 0885-8977, E-ISSN 1937-4208, Vol. 34, nr 2, s. 606-615Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A method is proposed in this paper to determine the harmonic impedances in low-voltage networks in a stochastic way. The consequences of resonances for harmonic propagation and stability of power converters are summarized. By using Monte Carlo simulation, the method includes the uncertainties in customer impedances, specifically due to electronic loads and local generation. The uncertainty in customer impedance is included by considering probability distribution for the resistive, inductive and capacitive parts of the impedance. The concept of transfer impedance is used for phase-to-neutral connections. A method is developed and applied to two existing low-voltage networks in Sweden. Results show that, for these two networks, the resonant frequencies decrease around 28 % once PV panels are installed. The paper includes a discussion of some of the practical aspects of applying the proposed method.

  • 126.
    Busatto, Tatiano
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Larsson, Anders
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Rönnberg, Sarah
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Supraharmonics Emission Assessment of Multi-level Converters Applied for Photovoltaic Grid-Connected Inverters2017Inngår i: The Renewable Energies and Power Quality Journal (RE&PQJ), ISSN 2172-038X, E-ISSN 2172-038X, Vol. 1, nr 15, s. 143-148, artikkel-id 252Artikkel i tidsskrift (Fagfellevurdert)
  • 127.
    Busatto, Tatiano
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Ravindran, Vineetha
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Larsson, Anders
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Estimation of the Consumer Electronics Capacitance for Harmonic Resonance Studies by a Non-Invasive Measurement Method2018Inngår i: Proceedings of International Conference on Harmonics and Quality of Power, ICHQP, Piscataway, NJ: Institute of Electrical and Electronics Engineers (IEEE), 2018, , s. 6Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Harmonic resonances in distribution systems are mainly between network inductances and shunt capacitances from capacitor banks and consumer loads. In this paper, particular attention is devoted to the evaluation of capacitances from domestic equipment, serving as a reference for resonance frequency studies. The assessment is performed by simulation and measurements of common low power electronic loads. From the analysis of EMI filters topologies used in AC/DC converters, a non-invasive capacitance measurement estimation method is presented. The method is verified after correlating capacitances with the resonance frequencies obtained from a frequency sweep method. From experimental measurements, the results show that the equivalent shunt capacitances for a set of 24 LED lamps are between 10 and 135 nF.

  • 128.
    Chang, G.W.
    et al.
    National Chung Cheng University.
    Ranade, S
    New Mexico State University.
    Watson, N.R.
    University of Canterbury.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Monitoring issues and analysis techniques: smart grid aspect of power quality2012Inngår i: 15th International Conference on Harmonics and Quality of Power (ICHQP), IEEE Communications Society, 2012, s. 673-677Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In recent years, many countries have started to integrate the power system with more advanced information and communication technologies. With transforming the electrical data to useful information, the stability and reliability of power system operation can be secured. By observing this world-wide trend, it is believed that the development of smart grid would be the vital strategy for energy saving, integration of renewable energy resources, and improvement of power quality. Meanwhile, the related measuring and control equipments are necessary to redesign based on information and communication technologies (ICT), which are key factors to the success of the smart grid implementation. This paper gives an overview of some important issues and techniques for the enhancement of power quality monitoring and analysis when deploying the smart grid.

  • 129. Chen, Yu
    et al.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Martins, Marcia
    Application of transfer function based harmonic study method to an offshore wind farm2012Konferansepaper (Fagfellevurdert)
  • 130.
    Cukalevski, Ninel
    et al.
    Mihailo Pupin Institute.
    Milanovic, Jovica V.
    University of Manchester, School of Electrical and Electronic Engineering, The University of Manchester.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    The Power Quality Monitoring for Transmission System in Liberalized Environment2014Konferansepaper (Fagfellevurdert)
  • 131.
    Cundeva, Snezana
    et al.
    University of Ss Cyril and Methodius, Faculty of Electrical Engineering and IT, Skopje.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Schwanz, Daphne
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hosting capacity of the grid for wind generators set by voltage magnitude and distortion levels2016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The hosting capacity, frequently defined as amount of distributed generation that can be connected to a certain location without resulting in an unacceptable quality or reliability for other customers, is limited. To know how much distributed generation can be connected in the grid it is important to define appropriate performance indicators. In this paper, the hosting capacity of the grid for wind power generation has been studied. Voltage magnitude and distortion levels are the performance indicators used to find the hosting capacity. A discussion is started on the interaction between windpower installations and the grid.

  • 132. Cundeva, Snezana
    et al.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Yang, Kai
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Distortion levels in the grid due to windpower integration2013Konferansepaper (Annet vitenskapelig)
  • 133.
    Cundeva, Snezana
    et al.
    University Ss. Cyril and Methodius Faculty of Electrical Engineering and IT Skopje.
    Krkoleva Mateska, Aleksandra
    University Ss. Cyril and Methodius Faculty of Electrical Engineering and IT Skopje.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hosting capacity of LV residential grid for uncoordinated ev charging2018Inngår i: Proceedings of International Conference on Harmonics and Quality of Power, ICHQP, Piscataway, NJ: Institute of Electrical and Electronics Engineers (IEEE), 2018Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The envisaged large penetration of electric vehicles (EVs) in the near future, brings new challenges to low voltage (LV) and medium voltage (MV) grids. For uncoordinated EV charging, the impact on the LV grid may be significant, due to the simultaneity between the residential power peak and the charging of EVs. The amount of EV chargers that can be connected to the grid without endangering the reliability or voltage quality for other customers is called the hosting capacity. This paper presents the analyses of the hosting capacity of a realistic LV residential network with 160 households for EV chargers. A stochastic approach is used, assuming that the EV chargers are randomly distributed over the households and the phases. For different EVs penetration rates in the network, the hosting capacity for slow chargers is determined. The results show that the EV penetration rate that the network can safely accept is 45%.

  • 134.
    de Oliveira, Tiago Elias Castelo
    et al.
    Electrical Energy Systems, Technological University of Eindhoven, Eindhoven, The Netherlands.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Ribeiro, Paulo Fernando
    Advanced Power Technologies and Innovations in Systems and Smart Grids Group, Federal University of Itajuba, Itajuba, Brazil.
    de Carvalho, Pedro M. S.
    Energy Scientific Area, Instituto Superior Tecnico, Lisbon, Portugal.
    Zambroni, Antônio C.
    Advanced Power Technologies and Innovations in Systems and Smart Grids Group, Federal University of Itajuba, Itajuba, Brazil.
    Bonatto, Benedito D.
    Advanced Power Technologies and Innovations in Systems and Smart Grids Group, Federal University of Itajuba, Itajuba, Brazil.
    The Concept of Dynamic Hosting Capacity for Distributed Energy Resources: Analytics and Practical Considerations2019Inngår i: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 12, nr 13, artikkel-id 2576Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The hosting capacity approach is presented as a planning, improving, and communication tool for electrical distribution systems operating under specific uncertainties, such as power quality issues, power stabilities, and reliability, among others. In other words, it is an important technique, when renewable sources are present, to answer the amount of power that is possible to supply to the system without trespassing power performance limits. However, the power flow in a distribution system, for instance, can change throughout time due to the penetration of distributed generation, as well as load consumption. Based on the dynamic nature existing in distribution grids nowadays, it is important to highlight that the hosting capacity should not be calculated in a specifically chosen time only, but must be analyzed throughout a period of time. Thus, this paper introduces an extended concept of hosting capacity in relation to an integrated impact of harmonic voltage distortion and voltage rise as a function of time for daily, weekly, monthly, or even yearly periods. This extended concept is named as Dynamic Hosting Capacity (DHC(t)). General aspects of DHC(t) are demonstrated via measured data on a photovoltaic system (PV) connected at a low-voltage (LV) side of a university building.

  • 135. Deuse, J.
    et al.
    Grenard, S.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    EU-DEEP integrated proect: technical implications of the "hosting-capacity" of the sytem for DER2008Inngår i: International Journal of Distributed Energy Resources, ISSN 1614-7138, Vol. 4, nr 1, s. 17-34Artikkel i tidsskrift (Fagfellevurdert)
  • 136. Deuse, J
    et al.
    Grenard, S
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Chuvychin, V
    Integration of DER & RES in power system and distribution network design2008Inngår i: CIGRE Sessions: CD ROM 2008 Session Papers, 2008Konferansepaper (Fagfellevurdert)
  • 137. Deuse, J
    et al.
    Grenard, S
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Häger, M
    Sollerkvist, F
    Effective impact of DER on distribution system protection2007Inngår i: Conference proceedings: 19th International Conference and Exhibition on Electricity Distribution : Vienna, 21 - 24 May 2007, Liege: AIM , 2007Konferansepaper (Fagfellevurdert)
  • 138. Deuse, J
    et al.
    Karoui, K
    Crisciu, H
    Gertmar, L
    Samuelsson, O
    Karlsson, P
    Chuvychin, V
    Ribickis, L
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Interactions of dispersed energy resources with power system in normal and emergency conditions2006Inngår i: Compte rendu de la session, CIGRE session 41 : 27 août > 1er septembre 2006 = Session proceedings, CIGRE session 41, Conseil International des Grands Réseaux Electriques , 2006Konferansepaper (Fagfellevurdert)
  • 139.
    Djokic, S
    et al.
    University of Edinburgh.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Reusel, K Van
    Katholieke Universiteit Leuven.
    Neumann, R
    Qualitrol.
    Stockman, K
    Howest.
    Gordon, J
    Endesa, Sevilla.
    Ethier, G
    Hydro-Québec Research’s Institute.
    Zavoda, F
    Hydro-Québec Research’s Institute.
    Cundeva, S
    Ss. Cyril and Methodius University.
    Stephens, M
    EPRI.
    UIE WG 2 power quality: recommendations to the stakeholderson voltage dip immunity of equipment and installations (after the CIGRE/CIRED/UIE joint WG C4.110)2012Konferansepaper (Fagfellevurdert)
  • 140.
    Djokic, S
    et al.
    University of Edinburgh.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Reusel, K Van
    Katholieke Universiteit Leuven.
    Neumann, R
    Qualitrol.
    Stockman, K
    Howest.
    Milanovic, J
    University of Manchester.
    UIE WG 2 power quality: further work and research on voltage dip immunity of equipment and installations (after the CIGRE/CIRED/UIE joint WG C4.110)2012Konferansepaper (Fagfellevurdert)
  • 141. Djokic, S
    et al.
    Stockman, K
    Howest.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Reusel, K Van
    Neumann, R
    Qualitrol.
    Marteyn, P
    Dow.
    UIE WG 2 power quality: the concept of process immunity time for the assessment of dip immunity of industrial processes (after the CIGRE/CIRED/UIE joint WG C4.110)2012Konferansepaper (Fagfellevurdert)
  • 142.
    Djokic, Sasa
    et al.
    School of Engineering and Electronics, University of Edinburgh.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Dip segmentation method2008Inngår i: 2008 13th International Conference on Harmonics and Quality of Power: [ICHQP 2008] ; Wollongong, Australia, 28 September - 1 October 2008, Piscataway, NJ: IEEE Communications Society, 2008Konferansepaper (Fagfellevurdert)
    Abstract [en]

    An alternative approach for the analysis of various types of dip events, termed Dip Segmentation Method, is presented in this paper. The description of a voltage dip in the proposed method includes both pre-dip and postdip parts/segments of a dip-related event, while the during-dip part is divided into a number of "during-event segments" and "transition segments". In that way, the proposed method allows for an improved assessment of standard and commonly used dip characteristics, incorporating, at the same time, several usually neglected characteristics, aspects and features of dip events into the analysis. After identifying the corresponding dip segments, direct correlation between the individual segments and particular effects on equipment operation could be established, allowing a more detailed description of the dip events and more accurate assessment of their influence on equipment performance.

  • 143. Du, C
    et al.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Power-frequency control for VSC-HVDC during island operation2006Inngår i: The 8th IEE International Conference on AC and DC Power Transmission : ACDC 2006 : 28 - 31 March 2006, [London], London: Institution of Engineering and Technology, 2006Konferansepaper (Fagfellevurdert)
  • 144.
    Du, C
    et al.
    ABB AB, HVDC System, Ludvika.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Agneholm, E
    Sannino, A
    ABB AB, Corporate research.
    A new control strategy of a VSC-HVDC System for high-quality supply of industrial plants2007Inngår i: IEEE Transactions on Power Delivery, ISSN 0885-8977, E-ISSN 1937-4208, Vol. 22, nr 4, s. 2386-2394Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper proposes a control strategy for a VSC-HVDC for improving the quality of power supply to industrial plants. The new idea of this control strategy is to give high priority to keep up the ac voltage and slightly decrease the frequency during disturbances. The motivation for choosing this strategy is that the sensitive processing industries are much more sensitive to voltage drops as compared with frequency deviations. In order to test this control strategy, the dynamic performance of a VSC-HVDC supplied industrial plant is investigated during sudden load disturbances, balanced and unbalanced faults from the grid. Simulation results obtained using PSCAD/EMTDC show that with the use of the proposed control strategy, the system can ride through disturbances such as motor starting and faults by slightly decreasing the frequency. The current limit of the VSC-HVDC converters has a significant influence on the dynamics of the system. An increase of the current limit significantly improves the power quality of the system. The comparison of the behavior between a pure ac supplied industrial plant and a VSC-HVDC supplied industrial plant clearly shows the capability of the VSC-HVDC to mitigate voltage dips during faults.

  • 145.
    Du, c.
    et al.
    Division of Electric Power Engineering, Department of Energy and Environment, Chalmers University of Technology.
    Sannino, A.
    ABB Corporate Research.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Analysis of response of VSC-based HVDC to unbalanced faults with different control systems2005Inngår i: Security and sustainable development under deregulation: 2005 IEEE/PES Transmission and Distribution Conference & Exhibition: Asia and Pacific : [August 14 - 18, 2005, Dalian, China] ; paper abstracts, Piscataway, NJ: IEEE Communications Society, 2005Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper investigates the dynamic performance of a VSC-HVDC system under unbalanced faults in ac systems. Three different control systems are presented and analyzed for the most common unbalanced fault, i.e. single-line-to-ground fault (SLGF) in PSCAD/EMTDC. Simulation results show that the system resumes normal operation after fault clearing using all three control systems, among which the third control system produces the best transient performance

  • 146.
    Ehnberg, S.G. Jimmy
    et al.
    Chalmers University of Technology.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Reliability of a small power system using solar power and hydro2005Inngår i: Electric power systems research, ISSN 0378-7796, E-ISSN 1873-2046, Vol. 74, nr 1, s. 119-127Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper studies the availability of the electricity supply when the sources consist of a combination of solar energy and a small hydro installation. Instead of flow-of-river, a small reservoir is used. By not using the hydro energy during sunny periods, the natural flow-of-river fills up the reservoir for later use. A model for global solar radiation is proposed with an astronomical part (deterministic) and a meteorological part (stochastic). The meteorological part is based on a Markov model of the cloud coverage. The solar model does not require solar radiation measurements, just cloud observations. A case study has been performed for Timbuktu (16.75°N, 0.07°W) in which generation availability is simulated for four different cases: solar power only; solar power with storage; solar and hydro power and solar and hydro power with storage. To be able to use exclusively renewable energy sources, a combination of sources is needed to secure the reliability of the supply. Using solar cells in combination with a small reservoir is favorable. Even with a weak flow the affect of the flow on the day time reliability is minor, but great benefits can be found for reliability during low load hours (night time).

  • 147. Esteves, Jorge
    et al.
    Brekke, Karstein
    Niall, Kevin
    Delfant, Maurizio
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Voltage quality monitoring, dips classification and responsibility sharing2011Inngår i: Proceeding of the International Conference on Electrical Power Quality and Utilisation, EPQU, IEEE Communications Society, 2011Konferansepaper (Fagfellevurdert)
    Abstract [en]

    CEER and EURELECTRIC cooperation in the field of quality of electricity supply, involving joint meetings and the participation at the relevant CENELEC Technical Committee, contributed to the results attained in the recent publication of the EN 50160:2010 edition that includes a new voltage dips classification table allowing harmonisation at European level on voltage dips data collection. The generalisation of voltage quality monitoring data publication all over Europe will allow the definition of responsibility sharing between the different involved stakeholders and the evolution of voltage quality regulation applied at national level. Examples from Sweden and Italy are briefly presented in this paper.

  • 148. Etherden, Nicholas
    et al.
    Ackeby, Susanne
    STRI AB.
    Bollen, Math
    STRI AB.
    Ohlsson, Lars
    Falbygdens Energi AB.
    Technical dimensioning of an energy storage for a Swedish distribution company2013Inngår i: 22nd International Conference and Exhibition on Electricity Distribution (CIRED 2013): Stockholm, Sweden, 10 - 13 June 2013, Red Hook, NY: Curran Associates, Inc., 2013, artikkel-id 315Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A grid-size energy-storage installation enables the removal of peak loads in the distribution system due to high amounts of wind production. In this paper the ability of a battery energy storage to increase the amount of wind power that can be connected to a distribution network is studied. It is found that about 40 % of overloading instances can be prevented with the storage. After this diminishing returns per unit of storage capacity occur and the overloading should instead be handled with curtailment. The extent to which the storage can minimise network losses was studied but the reduction in losses cannot compensate for the conversion losses in the storage installation.

  • 149.
    Etherden, Nicholas
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Dimensioning of Energy Storage for Increased Integration of Wind Power2013Inngår i: 2013 IEEE Power and Energy Society Generl Meeting (PES), Piscataway, NJ: IEEE Communications Society, 2013Konferansepaper (Fagfellevurdert)
  • 150.
    Etherden, Nicholas
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Bollen, Math
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Dimensioning of energy storage for increased integration of wind power2013Inngår i: IEEE Transactions on Sustainable Energy, ISSN 1949-3029, E-ISSN 1949-3037, Vol. 4, nr 3, s. 546-553Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Energy storage can potentially allow for more production from renewable resources into existing grids. A methodology to quantify grid limitations and dimension battery energy storage systems is presented in this paper. By use of grid consumption and production data, the hosting capacity methodology is developed as a general framework for storage dimensioning that can be applied by grid operators. The method is successfully applied to an existing subtransmission grid; actual hourly production and consumption data during a two-year period is used. The role of a storage system compared to other means to handle overloading is studied. It is found that about one third of overloading instances are suitable to handle with a battery energy storage system. After this, diminishing returns per unit of storage capacity are shown to occur.

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