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Mitigation of Voltage Unbalances Using a Line Voltage Regulator
2021 IEEE Madrid PowerTech, 2021With an increasing percentage of single-phase distributed energy resources and modern single-phase loads in the low voltage network, challenges are increasing for voltage grid operators. Especially the power quality in rural areas with long power cables is at risk. Voltage regulators such as on-load tap changers (OLTCs) or line-voltage regulators (LVRs)
Robert Jahn +2 more
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Voltage Unbalance Compensation in AC Microgrids
2021Environmental problems of the conventional power generation result in a tendency to increase the use of renewable energy, which in turn has altered the electrical power system. The increasing use of distributed generations over the last decade has led to the concept of Microgrids (MGs). MGs can operate in grid-connected or islanded mode.
Karimi, Shahram +2 more
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A solid state unbalance voltage compensator
12th IEEE International Power Electronics Congress, 2010This paper presents a Fast On-Load Tap Changing Regulator used to correct unbalanced voltages. This regulator uses the semi natural commutation in order to improve the response. The proposed topology injects the voltage in only phase in order to balance the three phase system.
Rodolfo Echavarria +2 more
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Comparative analysis between voltage unbalance definitions
2015 Workshop on Engineering Applications - International Congress on Engineering (WEA), 2015This paper describes different standards used to calculate voltage unbalance factor. Currently there are four definitions given from: IEEE (std. 1159 and 141), NEMA, and IEC, to calculate it. Variations of voltages using these 4 different definitions are presented in 3-D coordinates. The graphic relationship between them is analyzed.
Alex David Rodriguez +2 more
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Voltage unbalance emission assessment
Proceedings of the 2010 Electric Power Quality and Supply Reliability Conference, 2010Aim of this paper is to draw the attention on the principle origin for unbalance, taking into account the part caused by negative sequence currents as well as the part arising from non ideal grid impedance with non negligible coupling impedance between the positive and negative sequence system.
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Representing line voltage unbalance
Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344), 2003Representing the degree of voltage unbalance with the voltage unbalance factor (VUF) derived from symmetrical transformation requires complex phasor manipulations. This paper investigates various ways of representing VUF to facilitate the calculation in field applications.
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Voltage unbalance monitoring in CEB systems
10th International Conference on Harmonics and Quality of Power. Proceedings (Cat. No.02EX630), 2004Although the subject power quality has been treated by specialists of the area, it's incipient the number of investigation works referring to voltage unbalance. In this interim, the purpose of this work is to analyze, quantify and qualify the voltage unbalance, so that the results obtained here should be useful not only minimize harmful effects on the ...
M. de Oliveira +3 more
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Voltage unbalance emission assessment in radial power systems
2013 IEEE Power & Energy Society General Meeting, 2012Voltage unbalance (VU) emission assessment is an integral part in the VU-management process where loads are allocated a portion of the unbalance absorption capacity of the power system. The International Electrotechnical Commission Report IEC/TR 61000-3-13:2008 prescribes a VU emission allocation methodology establishing the fact that the VU can arise ...
Jayatunga, U, Perera, S, Ciufo, P
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Voltage unbalance numerical evaluation and minimization
Electric Power Systems Research, 2009Among a series of parameters, power quality studies are concerned with voltage unbalances, which represent the voltage magnitude and phase deviation from nominal values. In order to determine the influence of the network's parameters on voltage unbalances, and to provide exact solutions to reduce or even eliminate them, the present study develops and ...
Diogo C. Garcia +4 more
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Quantification of Voltage Unbalance Conditions
2014This paper confers the various effects of voltage unbalance on the performance of three-phase induction motor (3-Φ IM). The need of quantification of the voltage unbalance conditions is asserted to make precise and unique assessment of the performance 3-Φ IM.
Abhishek Chauhan +2 more
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