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  • 51.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Cundeva, S.
    University Sts. Cyrill and Methodias, Skopje.
    Gordon, J-M. R.
    Endesa, Sevilla.
    Djokic, S.Z.
    University of Edinburgh.
    Stockman, K.
    Ghent University.
    Milanovic, J.V.
    University of Manchester.
    Neumann, Robert
    Qualitrol, Belfast.
    Ethier, G.
    Hydro-Québec Research’s Institute.
    Voltage dip immunity aspects of power electronics equipment: Recommendations from CIGRE/CIRED/UIE JWG C4.1102011In: Proceeding of the International Conference on Electrical Power Quality and Utilisation, EPQU, IEEE Communications Society, 2011, p. 803-810Conference paper (Refereed)
    Abstract [en]

    This paper presents some of the results from an international working group on voltage-dip immunity. The working group has made a number of recommendations to reduce the adverse impact of voltage dips. Specific recommendations to researchers and manufacturers of power-electronic equipment are: considering all voltage dip characteristics early in the design of equipment; characterize performance of equipment by means of voltage-dip immunity curves; and made equipment with different immunity available.

  • 52.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Cundeva, S.
    University Sts. Cyrill and Methodias, Skopje.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Wahlberg, Mats
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Yang, Kai
    Yao, L
    Areva T and D, Technology Centre, Stafford.
    A wind park emitting characteristic and non-characteristic harmonics2010In: 2010 14th International Power Electronics and Motion Control Conference (EPE/PEMC 2010): Ohrid, Macedonia, 6 - 8 September 2010, Piscataway, NJ: IEEE Communications Society, 2010, p. S14-22-S14-26Conference paper (Refereed)
    Abstract [en]

    This paper shows measurements of the emission of harmonics by a small windpark. The spectrum consists of the characteristic harmonics associated with six-pulse converters and a broadband spectrum covering frequencies at which emission normally is not present. These frequencies are caused by the switching pattern of the power-electronics converters. Similar spectra have been reported by other authors and for other types of modern converters. Whereas the actual emission is small, the presence of emission at non-characteristic frequencies could result in voltage distortion limits being exceeded.

  • 53.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Das, Ratan
    IcaPower LLC, Dover, DE.
    Djokic, Sasa Z.
    University of Edinburgh, School of Engineering and Electronics, University of Edinburgh.
    Ciufo, Phil
    University of Wollongong.
    Meyer, Jan
    Institute of Electrical Power Systems and High Voltage Engineering, Technische Universitaet Dresden, Technical University Dresden, Dresden University of Technology.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Zavoda, Francisc
    IREQ, IREQ/HQ, Hydro-Québec Research’s Institute.
    Power Quality Concerns in Implementing Smart Distribution-Grid Applications2017In: IEEE Transactions on Smart Grid, ISSN 1949-3053, E-ISSN 1949-3061, Vol. 8, no 1, p. 391-399, article id 7527692Article in journal (Refereed)
    Abstract [en]

    This paper maps the expected and possible adverse consequences for power quality of introducing several smart distribution-grid technologies and applications. The material presented in this paper is the result of discussions in an international CIGRE-CIRED joint working group. The following technologies and applications are discussed: microgrids; advanced voltage control; feeder reconfiguration; and demand-side management. Recommendations are given based on the mapping.

  • 54.
    Bollen, Math
    et al.
    STRI AB.
    Etherden, Nicholas
    STRI AB.
    Tjäder, J.
    STRI AB.
    Increasing hosting capacity through dynamic line rating: risk aspects2015Conference paper (Refereed)
    Abstract [en]

    The availability of monitoring, control and communication technology makes it possible to estimate the ampacity of an overhead transmission line continuously. This allows the transport of substantially larger amounts of energy over that line that when a static ampacity value is used. It is shown in this paper that the use of such dynamic line rating allows more wind power to be connected to the grid, i.e. it results in an increase of the hosting capacity. For the numerical example presented in the paper, the hosting capacity is increase from 214 to 390 MW. There are different types of risk associated with the introduction of dynamic line rating, some of which are discussed in this paper. Two main types of risk are distinguished. Risks associated with possible overload of components, even when the ampacity is exactly known. Additional risks due to the difference between the actual and the estimated ampacity.The introduction of curtailment, in combination with dynamic line rating, makes it possible to manage the first type of risk. The risk of overload carried by all customers is replaced by the risk of temporality being disconnected for the wind-park owner. The latter is however also the stakeholder gaining most from the increase in hosting capacity.To reduce the second type of risk, several practical aspects need to be considered before implementing dynamic line rating, several of which are discussed in this paper.

  • 55.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Etherden, Nicholas
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Yang, Kai
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Chang, G. W
    National Chung Cheng University.
    Continuity of supply and voltage quality in the electricity network of the future2012In: 15th International Conference on Harmonics and Quality of Power (ICHQP), IEEE Communications Society, 2012, p. 375-377Conference paper (Refereed)
    Abstract [en]

    This paper introduces three examples of new thinking for addressing the challenges that the power system has to cope with. Such new thinking in combination with new technology will be an important element in the transition to the future electricity network (the —). With overload protection it is important to not remove the overloaded component but the cause of the overload so as to protect the other network users against an interruption. The limits set to the hosting capacity by potential overvoltages can be removed either by new technology (curtailment of production) or by allowing occasional overvoltages. Allowing higher levels of non-characteristic harmonics is a possible alternative for strict emission limits on new installations. In all cases it is essential that the interests of the network user are considered.

  • 56.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Gordon, José Romero
    Endesa, Sevilla.
    Djokic, Sasa Z
    University of Edinburgh.
    Stockman, Kurt
    Ghent University.
    Milanovic, Jovica V
    University of Manchester.
    Neumann, Robert
    Qualitrol, Belfast.
    Ethier, Gaetan
    Hydro-Québec Research’s Institute.
    Voltage-dip immunity: statistics and need for further work2010In: ICREPQ'10, European Association for the Development of Renewable Energies, Environment and Power Quality , 2010Conference paper (Refereed)
  • 57.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Gu, Irene
    Signal processing of power-quality disturbances2006Book (Other (popular science, discussion, etc.))
  • 58.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Gu, Irene Y.H.
    Eindhoven University of Technology.
    Santoso, Surya
    University of Texas, Austin.
    McGranaghan, Mark F.
    University of Manchester.
    Crossley, Peter A.
    University of Manchester.
    Ribeiro, Moises V
    Universidade Federal de Pernambuco, Recife.
    Ribeiro, Paulo F.
    Universidade Federal de Pernambuco, Recife.
    Bridging the gap between signal and power2009In: IEEE signal processing magazine (Print), ISSN 1053-5888, E-ISSN 1558-0792, Vol. 26, no 4, p. 12-31Article in journal (Refereed)
    Abstract [en]

    Signal processing has been used in many different applications, including electric power systems. This is an important category, since a wide variety of digital measurements is available and data analysis is required to deliver diagnostic solutions and correlation with known behaviors. Measurements are taken at numerous locations, and the analysis of data applies to a variety of issues in ¿ power quality (PQ) and reliability ¿ power system and equipment diagnostics ¿ power system control ¿ power system protection. This article focuses on problems and issues related to PQ and power system diagnostics, in particular those where signal processing techniques are extremely important. PQ is a general term that describes the quality of voltage and current waveforms. PQ problems include all electric power problems or disturbances in the supply system that prevent end-user equipment from operating properly. Examples of voltage and current variations that can result in PQ problems include voltage interruptions, long- and short-duration voltage variations, steady-state research opportunities that use the measured voltages and currents to indicate possible equipment and system problems (referred to as equipment diagnostics).

  • 59.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Gu, I.Y.H
    Analysis and classification of power quality disturbances: ideas, methods and techniques2006In: 12th International Conference on Harmonics and Quality of Power, 2006Conference paper (Refereed)
  • 60.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Gu, I.Y.H.
    Characterization of voltage variations in the very-short time-scale2005In: IEEE Transactions on Power Delivery, ISSN 0885-8977, E-ISSN 1937-4208, Vol. 20, no 2, p. 1198-1199Article in journal (Refereed)
    Abstract [en]

    This letter presents a method for characterizing the fast voltage variations that occur on a time scale between the subsecond fluctuations covered by the flickermeter standard and the 10-min values covered by standards like EN 50160 The method is fully compatible with IEC 61000-4-30 class A. The new characteristic is correlated to small switching actions, such as domestic load switching and transformer tap-changer operation.

  • 61.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Gu, I.Y.H
    Chalmers University of Technology, Department of Signals and Systems.
    On the analysis of voltage and current transients in three-phase power systems2007In: IEEE Transactions on Power Delivery, ISSN 0885-8977, E-ISSN 1937-4208, Vol. 22, no 2, p. 1194-1201Article in journal (Refereed)
    Abstract [en]

    This paper proposes a method for analyzing measurements of voltage transients in three-phase systems. The method is based on the Clarke transform introduced in 1950 for calculations of travelling waves along three-phase transmission lines. The proposed method also shows close similarities with the classification of three-phase unbalanced voltage dips. After extracting the actual transient (e.g., by using a notch filter centered on the power-system frequency), the three signals are decomposed into seven components. From the relation between these seven components, the dominant component is identified. The method is successfully applied to a number of measured transients. The paper also identifies the limitations of the method and gives suggestions for future work

  • 62.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Gu, I.Y.H
    Chalmers University of Technology, Department of Signals and Systems.
    Axelberg, P.G.V
    Chalmers University of Technology, Department of Signals and Systems.
    Styvaktakis, E
    Hellenic Transmission System Operator.
    Classification of underlying causes of power quality disturbances: deterministic versus statistical methods2007In: EURASIP Journal on Advances in Signal Processing, ISSN 1687-6172, E-ISSN 1687-6180Article in journal (Refereed)
    Abstract [en]

    This paper presents the two main types of classification methods for power quality disturbances based on underlying causes: deterministic classification, giving an expert system as an example, and statistical classification, with support vector machines (a novel method) as an example. An expert system is suitable when one has limited amount of data and sufficient power system expert knowledge; however, its application requires a set of threshold values. Statistical methods are suitable when large amount of data is available for training. Two important issues to guarantee the effectiveness of a classifier, data segmentation, and feature extraction are discussed. Segmentation of a sequence of data recording is preprocessing to partition the data into segments each representing a duration containing either an event or a transition between two events. Extraction of features is applied to each segment individually. Some useful features and their effectiveness are then discussed. Some experimental results are included for demonstrating the effectiveness of both systems. Finally, conclusions are given together with the discussion of some future research directions.

  • 63.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Hassan, F
    Yang, Y
    Limitations set by the distribution network against the large-scale integration of distributed energy resources2008Conference paper (Other academic)
  • 64.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Hassan, Fainan
    Integration of distributed generation in the power system2011Book (Other (popular science, discussion, etc.))
    Abstract [en]

    Distributed Generation (DG) reduces the amount of energy lost in transmitting electricity because the electricity is generated very near where it is used. This book introduces systematic and transparent methods for quantifying the impact of DG on the power grid. It emphasizes systematic and transparent calculation methods, allowing for a quantification of the amount of DG that can be integrated at a certain location of the grid or in the grid as a whole. It also provides an overview of the different energy sources, with emphasis on wind power, solar power and combined heat and power in the power grid.

  • 65.
    Bollen, Math
    et al.
    STRI AB.
    Hassan, Fainan
    STRI AB.
    Wämundsson, Mikael
    STRI AB.
    Holm, Anders
    Vattenfall Research & Development.
    He, Ying
    Vattenfall Research & Development.
    The active use of distributed generation in network planning2009In: CIRED 20th International Conference on Electricity Distribution: (CIRED 2009) ; Prague, Czech Republic, 8 - 11 June 2009, Red Hook, NY: Curran Associates, Inc., 2009, article id 0150Conference paper (Refereed)
    Abstract [en]

    This paper addresses ways in which distributed generation can be used to the advantage of network operators. A distinction is thereby made between "non-controlled generation" and "controlled generation". Both types can contribute to an improved performance of the network, where the opportunities for controlled generation are obviously much bigger. It is shown that non-controlled generation can have a positive impact on losses, on undervoltages and on reliability. Controlled generation can further mitigate fast voltage fluctuations, voltage dips and harmonic distortion.

  • 66.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Holm, A
    He, Y
    Owe, P
    A customer-oriented approach towards reliability indices2007In: Conference proceedings: 19th International Conference and Exhibition on Electricity Distribution : Vienna, 21 - 24 May 2007, Liege: AIM , 2007Conference paper (Refereed)
    Abstract [en]

    This paper introduces a reliability index that is directly linked to the satisfaction of individual customers with the experienced reliability of supply. The definition of the index is based on the observation that customers are satisfied as long as they have less than 3 interruptions per year, none of which lasts longer than 8 hours. The customer dissatisfaction index (CDI) is defined as the probability that this condition is fulfilled for a given customer. Mathematical expressions are obtained for the CDI; its relation with existing indices is studied; and the results of a case study in a medium-voltage distribution network are presented.

  • 67.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Hooshyar, Hossein
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Spread of high frequency current emission2013In: 22nd International Conference and Exhibition on Electricity Distribution (CIRED 2013): Stockholm, Sweden, 10 - 13 June 2013, Red Hook, NY: Curran Associates, Inc., 2013, article id 209Conference paper (Refereed)
    Abstract [en]

    This paper investigates the spread of the high frequency current emission between devices of different size and the grid. The impact of the EMC filter, either LCL or CLC configuration, has been considered from a simplified model. The high frequency current emission, produced by a large device, can potentially cause a relatively large current flowing through a nearby small device. An important conclusion from the study is that current amplification can occur due to harmonic resonances between different types of filters.

  • 68.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Häger, Mats
    Power quality: interactions between distributed energy resources,the grid, and other customers2005In: Leonardo EnergyArticle in journal (Other academic)
    Abstract [en]

    This paper presents the three aspects of power quality concerning distributed energy resources (DER). The voltage quality experienced by a DER unit impacts the performance of the unit: bad voltage quality may reduce the life length of the unit and lead to incorrect operation or tripping. The DER unit's current (the "current quality" impacts the system and through the system other customers. The hosting-capacity concept is proposed as a systematic method for quantifying the impact of DER units. The third aspect of power quality only appears with large (local or global) penetration of DER. The tripping of DER units on voltage dips or frequency swing endangers the reliability, stability and security of the system.

  • 69.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Häger, Mats
    What is reliability?: Reliability and reliability indices in the viewpoint of the network operator and in the viewpoint of the customer2006In: Electrical Power Quality and Utilization, ISSN 1234-6799, Vol. 2, no 2Article in journal (Other academic)
  • 70.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Häger, Mats
    Olofsson, M
    Allocation of emission limits for individual emitters at different voltage levels: flicker and harmonics2010Conference paper (Refereed)
  • 71.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Karlsson, Daniel E.
    STRI AB, Ludvika.
    Lennerhag, Oscar
    STRI AB, Sweden.
    Different Fault Types and Voltage Dips in relation to Shielding of Subtransmission Lines2016In: 2016 17th International Conference on Harmonics and Quality of Power, Piscataway, NJ, 2016, p. 518-523, article id 7783470Conference paper (Refereed)
    Abstract [en]

    This paper presents a method for considering the voltage-dip performance of the power system in the design of subtransmission lines. The shielding performance of the lines is expressed in terms of the number of faults for different number of phases involved in the fault. Relations between fault type and voltage dip at the terminals of sensitive equipment are used to determine the resulting number of equipment trips. The method is illustrated by applying it to three different tower designs used in the Swedish subtransmission networks. It is shown that the installation of shield wires significantly reduces the number of equipment trips, especially in combination with the installation of additional capacitance in adjustable-speed drives.

  • 72. Bollen, Math
    et al.
    Kolessar, Rémy
    Energy Markets Inspectorate.
    Gustavsson, Bengt
    Energy Markets Inspectorate.
    Torstensson, Daniel
    Energy Markets Inspectorate.
    Albertsson, Peter
    Energy Markets Inspectorate.
    Westergaard, Thomas
    Energy Markets Inspectorate.
    The Swedish government inquiry on smart meters and intelligent networks2011In: Proceedings of CIRED 21st International Conference on Electricity Distribution, 2011, article id 0160Conference paper (Refereed)
    Abstract [en]

    The Energy Markets Inspectorate has conducted an inquiry on smart grids during 2010 and submitted the resulting report to the Swedish government. The inquiry has identified a number of barriers against the introduction of new technology and a number of proposals are made to remove the barriers: an independent council to gather and spread knowledge on smart grids; incentives for network operators to create new services and increase network performance; an action plan for the future development of the electricity network; a new structure of network tariffs to reduce peak loads and price peaks; and functionality requirements on information to customers to allow them to actively participate in the market.

  • 73.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Lundmark, Martin
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Boije, Christer
    Åkerlund, John
    A short note on calculating power for energy-efficient lighting and other non-linear loads2009Report (Other academic)
  • 74.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Lundmark, Martin
    Boije, Christer
    Åkerlund, John
    Kort genomgång av effektberäkningar för lågenergilampor och andra olinjära laster2009Report (Other academic)
  • 75.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    McMichael, Ian
    Power Quality Solution.
    Stephens, Mark
    EPRI.
    Stockman, Kurt
    Hogeschool West, Vlaanderen, Kortrijk.
    Djokic, Sasa
    University of Edinburgh.
    Zavoda, Francisc
    IREQ.
    Brumsickle, Bill
    Soft Switchning Technology.
    McEachern, Alex
    Power Standards Lab.
    Gordon, José Romero
    Endesa, Sevilla.
    Ethier, Gaetan
    Hydro-Québec Research’s Institute.
    Neumann, Robert
    Qualitrol.
    CIGRE/CIRED/UIE JWG C4.110 - Voltagedip immunity of equipment in installations: status April 20082008In: 2008 13th International Conference on Harmonics and Quality of Power: [ICHQP 2008] ; Wollongong, Australia, 28 September - 1 October 2008, Piscataway, NJ: IEEE Communications Society, 2008Conference paper (Refereed)
    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. The scope of the working group is to gather technical knowledge on the immunity of equipment, installations and processes against voltage dips, and to use this knowledge in the further development of methods and standards. The activities of the working group are divided in seven "chapters". Chapters 1 and 7 are introduction and conclusions, respectively. Chapter 2 gives a general description of voltage dips as they appear at the terminals of sensitive equipment. Chapter 3 describes the performance of equipment and processes during voltage dips. This chapter also includes recommendations on the design of processes. In Chapter 4 the results from Chapter 2 and Chapter 3 are combined to set requirements for the dip characteristics that should be included in immunity testing. Chapter 5 is the data gathering chapter, covering data on voltage-dip statistics at different locations, but also data on the economics of equipment immunity and testing. Finally, in Chapter 6, recommendations for immunity objectives will be given. Important contributions of the working group are: a check-list of voltage dip characteristics to be used early in the design of equipment; a methodology to assess the performance of a complete installation and to include voltage-dip performance in the design of the installation; recommendations for characterization testing of equipment against voltage dips; recommendations for voltagedip immunity of equipment.

  • 76.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Meyer, Jan
    Dresden University of Technology.
    Amaris, Hortensia
    University Carlos III, Madrid.
    Blanco, Ana María
    Technical University Dresden.
    Gil-de-Castro, Aurora
    University of Cordoba.
    Desmet, Jan
    Ghent University.
    Klatt, Mattias
    Technical University Dresden.
    Kocewiak, Lukasz
    DONG Energy Wind Power, Fredericia.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Yang, Kai
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Future work on harmonics: some expert opinions part I – wind and solar power2014Article in journal (Refereed)
    Abstract [en]

    A workshop on power system harmonics was organized in Stockholm in January 2014. On the agenda was among others a discussion on what are the main issues on harmonics at the moment and in the near future. The results of this discussion are summarized in this paper and some of the issues are discussed in more detail in this paper and in its companion paper. This paper discusses emission from wind and solar power as well as advantages and disadvantages of active and passive filters.

  • 77.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Milanovic, J. V
    University of Manchester.
    Čukalevski, N
    Mihailo Pupin Institute.
    CIGRE/CIRED JWG C4.112: Power Quality Monitoring2014Conference paper (Refereed)
  • 78.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Mousavi-Gargari, S
    Harmonic resonances due to transmission cables2014Conference paper (Refereed)
  • 79.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Mousavi-Gargari, S
    Tennet, P.O.Box 718, 6800 AS Arnhem.
    Bahramirad, S
    ComEd, Chicago.
    Harmonic resonances due to transmission-system cables2014In: The Renewable Energies and Power Quality Journal (RE&PQJ), ISSN 2172-038X, E-ISSN 2172-038X, no 12, article id 463Article in journal (Refereed)
    Abstract [en]

    This paper gives some examples of harmonicissues that can occur when long ac cables are connected in thetransmission grid. The main impact is that resonances can occurat much lower frequencies than when only overhead lines arepresent. Two illustrative case studies are presented: one for a275-kV cable, one for a 400-kV cable in combination with a 132-kV capacitor bank. A simple rule-of-thumb is given, to decide ifa detailed harmonic study is needed. Some guidelines for such astudy are given as well.

  • 80.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Mulenga, Enock
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Etherden, Nicholas
    Hosting Capacity of the Grid for Photovoltaic Installations: a Stochastic Approach Applied to Single-phase Connections2018In: 8th Solar Integration Workshop, 2018, p. 1-7, article id 6A_1_SIW18_046Conference paper (Refereed)
    Abstract [en]

    This paper discusses the voltage rise due to PV installations connected to a low-voltage network. The connection of individual installations is studies for both single-phase and three-phase connection. A stochastic method is presented to estimate the hosting capacity. This method is illustrated for random and coordinated connection of single-phase installations. It is shown, in a number of ways, that the installation of large (e.g. 6 kW) single-phase connected units can easily result in unacceptable overvoltages.

  • 81.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Olofsson, Magnus
    Elforsk.
    Consumer electronics and the power grid: what are they doing to each other?2015In: I E E E Consumer Electronics Magazine, ISSN 2162-2248, Vol. 4, no 1, p. 50-57, article id 6985955Article in journal (Refereed)
    Abstract [en]

    Consumer electronic devices mostly get their energy from the electric power grid. Such devices might be continuously connected to the grid (like televisions) or only connected to charge the batteries (like cell phones). The amount of energy taken from the grid is not reduced by using devices powered by batteries. Instead, the electrical energy consumption is more likely increased due to the losses in the conversion process and because there are more opportunities to use the device.

  • 82.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Olofsson, Magnus
    Elforsk.
    Larsson, Anders
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Lundmark, Martin
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Standards for supraharmonics (2 to 150 kHz)2014In: IEEE Electromagnetic Compatibility Magazine, ISSN 2162-2264, Vol. 3, no 1, p. 114-119Article in journal (Refereed)
    Abstract [en]

    There is a serious interest from the international standard-setting community in knowledge about voltage and current distortion in the frequency range 2 to 150 kHz, referred to as supraharmonics. At the same time, research is ongoing at a number of locations, but the knowledge about supraharmonics remains limited. This paper compares some of the properties of harmonics and supraharmonics. An increase in supraharmonics for individual devices is observed in association with a decrease in harmonic emission (i.e. below 2 kHz). A proposal is made for setting limits in this frequency range. The proposal is based on existing standards and is meant to be for discussion. The authors strongly encourage an open discussion about the proposed limits. There are a number of differences between harmonics and supraharmonics that are not covered by the proposed set of limits. A substantial amount of further research is needed to extend the standard framework for supraharmonics such that this can be covered by standards

  • 83.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Ribeiro, Paulo F.
    The smart grid concept evolution2013In: Standard handbook for electrical engineers, New York: McGraw-Hill Companies , 2013, 16Chapter in book (Refereed)
  • 84.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Ribeiro, Paulo
    Calvin College, Grand Rapids, MI.
    Gu, Irene Y H
    Chalmers University of Technology.
    Duque, Carlos A.
    Federal University of Juiz de Fora, Minas Gerais.
    Trends, challenges and opportunities in power quality research2010In: European transactions on electrical power, ISSN 1430-144X, E-ISSN 1546-3109, Vol. 20, no 1, p. 3-18Article in journal (Refereed)
    Abstract [en]

    This paper outlines a number of possible research directions in power quality. The introduction of new sources of generation will introduce the need for new research on voltage-magnitude variations, harmonic emission and harmonic resonance. Statistical performance indicators are expected to play an important role in addressing the hosting capacity of the power system for these new sources. The quickly growing amounts of power-quality data call for automatic analysis methods. Advanced signal-processing tools need to be developed and applied to address this challenge. Equipment with an active power-electronic interface generates waveform distortion at higher frequencies than existing equipment. The emission, spread, consequences and mitigation of this distortion require more research emphasis. The growing complexity of the power system calls for remote identification of system events and load transitions. Future DC networks, at different voltage levels, require the research on DC power quality next to AC power quality. Research on methods to describe and analyse time-varying harmonics has applications in a number of the above-mentioned issues. So does the use of hardware-in-the-loop (HIL) and real-time-digital simulation. Existing power quality standards should not form a barrier against future research; instead research should result in improved standards as well as completely new concepts. Examples are: voltage dips in three-phase systems, flicker due to non-incandescent lamps, and voltage variations on the timescale between 1 second and 10 minutes. All together, it is concluded in this paper that sufficient important and interesting research challenges and opportunities remain in the power quality area.

  • 85.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Ribeiro, Paulo
    Calvin College, Grand Rapids, MI.
    Larsson, Anders
    Lundmark, Martin
    Limits for voltage distortion in the frequency range 2 to 9 kHz2008In: IEEE Transactions on Power Delivery, ISSN 0885-8977, E-ISSN 1937-4208, Vol. 23, no 3, p. 1481-1487Article in journal (Refereed)
    Abstract [en]

    This paper addresses voltage distortion in the frequency range 2 to 9 kHz, above what is normally considered in harmonic studies. By extrapolating the voltage-distortion limits that exist in international standards for distortion up to 2 kHz, it is concluded that 0.5% of nominal voltage per 200-Hz band is a safe limit. This limit is next used to estimate the number of small generator units (1-10 kW) that can be connected to a low-voltage grid. It is concluded that in some cases the connection of one or just a few units already leads to a distortion level above the limit.

  • 86.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Hosting Capacity of the Power Grid for Renewable Electricity Production and New Large Consumption Equipment2017In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 10, no 9, article id 1325Article in journal (Refereed)
    Abstract [en]

    After a brief historical introduction to the hosting-capacity approach, the hosting capacity is presented in this paper as a tool for distribution-system planning under uncertainty. This tool is illustrated by evaluating the readiness of two low-voltage networks for increasing amounts of customers with PV panels or with EV chargers. Both undervoltage and overvoltage are considered in the studies presented here. Probability distribution functions are calculated for the worst-case overvoltage and undervoltage as a function of the number of customers with PV or EV chargers. These distributions are used to obtain 90th percentile values that act as a performance index. This index is compared with an overvoltage or undervoltage limit to get the hosting capacity. General aspects of the hosting-capacity calculations (performance indices, limits, and calculation methods) are discussed for a number of other phenomena: overcurrent; fast voltage magnitude variations; voltage unbalance; harmonics and supraharmonics. The need for gathering data and further development of models for existing demand is emphasised in the discussion and conclusions

  • 87.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Modelling and simulation issues resulting from extended measurements2015In: 2015 IEEE Power & Energy Society General Meeting: 26-30 July 2015, Denver CO, Piscataway, NJ: IEEE Communications Society, 2015, article id 7285961Conference paper (Refereed)
    Abstract [en]

    Presents a collection slides covering the following topics: supraharmonics propagation; measurement modeling; grid supply terminals; device terminals; secondary emission; primary emission; voltage measurement and capacitor

  • 88.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Nya lågspänningslaster och störningar i frekvensområdet 2 till 150 kHz: resultat från forskningsprojektet vid Luleå tekniska universitet, samt en kartläggning av behovet på ytterligare forskning2011Report (Other academic)
  • 89.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Primary and Secondary Harmonics Emission: Harmonic interaction - A set of definitions2016In: 2016 17th International Conference on Harmonics and Quality of Power, Piscataway, NJ: IEEE Computer Society, 2016, p. 703-708, article id 7783333Conference paper (Refereed)
    Abstract [en]

    This paper proposes a set of definitions to simplify the discussion about the different contributions to the harmonic currents at the terminals of a device or an installation. Definitions are given, and explained, for 'primary harmonic emission', 'secondary harmonic emission', and 'harmonic interaction'

  • 90.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Larsson, Anders
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Wahlberg, Mats
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Lundmark, Martin
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Harmonic emission from installations with energy-efficient lighting2011In: Proceeding of the International Conference on Electrical Power Quality and Utilisation, EPQU, Piscataway, NJ: IEEE Communications Society, 2011, p. 797-802Conference paper (Refereed)
    Abstract [en]

    This paper presents the results from a number of measurements of the harmonic emission from installations that contain a large number of energy-efficient lamps. Two of the measurements concern the replacement of incandescent lamps with CFL and LED; the other measurement concerns an installation with up to 48 fluorescent lamps with high-frequency ballasts. The paper also contains a discussion on why the (total) power factor is not a good measure to quantify the performance of lamps or installations containing large numbers of lamps

  • 91.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Wahlberg, Mats
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Laboratory and field measurements of the power factor and the harmonic emission from energy-efficient lamps2011Conference paper (Refereed)
  • 92.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Zavoda, Francisc
    IREQ, IREQ/HQ, Hydro-Québec Research’s Institute.
    CIGRE/CIRED C4.24 – power quality in the future grid – first introduction2014Conference paper (Refereed)
  • 93.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Zavoda, Francisc
    IREQ (HQ), Varennes.
    Langella, Roberto
    Second University of Naples.
    Djokic, Sasa
    University of Edinburgh.
    Cuifo, Philip
    University of Wollongong.
    Meyer, Jan Christian
    Technische Universitaet Dresden.
    Cuk, Vladimir
    Eindhoven University of Technology.
    Consequences of Smart Grids for Power Quality Overview of the Results from CIGRE Joint Working Group C4.24/CIRED2018In: 2017 IEEE PES Innovative Smart Grid Technologies Conference Europe, ISGT-Europe 2017: proceedings, New York: Institute of Electrical and Electronics Engineers (IEEE), 2018Conference paper (Refereed)
    Abstract [en]

    This paper gives an overview of the expected unintended (negative) consequences for power quality of several on-going developments in the power system. Four developments directly related to smart-grid technology are covered: microgrids; advanced voltage control; feeder reconfiguration; and demand-side management. Four developments indirectly related are also covered: new sources of electricity production; increased used of active power-electronic converters; shift from overhead lines to cables; and new types of lighting. The paper summarizes the discussions in an international working group and presents the main findings are recommendations.

  • 94.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Zavoda, Francisc
    IREQ.
    Zhong, Jin
    University of Hongkong.
    Djokic, Sasa
    University of Edinburgh.
    Das, Ratan
    ABB.
    Halpin, Mark
    Auburn University Montgomery, Alabama.
    CIGRE/CIRED working group C4.24 – power quality and EMC issues associated with future electricity networks – status report2015Conference paper (Refereed)
    Abstract [en]

    This paper gives a status report of joint working group C4.24. Next to an overview of the different activities started, more details are given of the work done on voltage dips, new sources of emission, feeder reconfiguration, demand side management and power quality and economics.

  • 95.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Sabin, D.D
    International coordination for voltage sag indices2006In: 2006 IEEE/PES Transmission & Distribution Conference and Exposition: Latin America : Caracas, Venezuela, 15-18 August 2006, Piscataway, NJ: IEEE Communications Society, 2006Conference paper (Refereed)
  • 96.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Samuelsson, O.
    Lund University.
    Controlled island operation of part of the 50-kV grid in Southern Sweden2009In: 2009 IEEE Bucharest PowerTech Proceedings: Bucharest, Romania June 28 - July 2, 2009 / [ed] Lucian Toma, Piscataway, NJ :: IEEE Communications Society, 2009Conference paper (Refereed)
    Abstract [en]

    This paper is based on measurements obtained during a test of controlled islanding of part of the 50-kV grid in Southern Sweden. The purpose of the test was to verify operation of generator controls during islanding. The variations in voltage magnitude and frequency are shown as well as flicker severity and very-short variations. A number of performance indices have been calculated and compared with limits. Voltage magnitude and frequency have been studied in some detail around the disconnection and reconnection instants. The frequency varies much more during the island operation than during grid-connected operation. Voltage magnitude variations and flicker remain within their normal range. However the variations in the time range between 3 seconds and 10 minute appear to be higher than normal.

  • 97.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Schwaegerl, C
    Schmitt, S
    Distributed energy resources and waveform distortion2007In: Conference proceedings: 19th International Conference and Exhibition on Electricity Distribution : Vienna, 21 - 24 May 2007, Liege: AIM , 2007Conference paper (Refereed)
  • 98.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Sollerkvist, F
    The hosting capacity of distribution networks against high-frequency harmonics emitted by distributed energy resources2006In: 12th International Conference on Harmonics and Quality of Power, 2006Conference paper (Refereed)
  • 99.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Sollerkvist, Frans
    Larsson, Anders
    Lundmark, Martin
    Limits to the hosting capacity of the grid for equipment emitting high-frequency distortion2006In: Proceedings of Nordic Distribution and Asset Management Conference: NORDAC 2006, 2006Conference paper (Refereed)
  • 100.
    Bollen, Math
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Speychal, M
    STRI AB.
    Lindén, K
    STRI AB.
    Estimation of dip frequency from fault statistics: including three-phase characteristics2006In: International Conference on Probabilistic Methods Applied to Power Systems, 2006: PMAPS 2006 ; 11 - 15 June 2006, [Stockhom, Sweden], Piscataway, NJ: IEEE Communications Society, 2006Conference paper (Refereed)
    Abstract [en]

    This paper describes methods for estimating the voltage dip frequency, due to faults, experienced by customers. The input to the calculation consists of fault statistics from network operators. The calculations are based on the method of fault positions, extended with a three-phase classification of voltage dips

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