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Three-phase sigma-delta modulation using zero-sequence components
2005 European Conference on Power Electronics and Applications, 2005This paper presents new analytic results on the performance of sigma-delta modulated (SDM) three-phase voltage source inverters, in terms of harmonic distortion of output current, conduction and switching losses of the inverter devices, and rms current of the DC link capacitor. The results are compared with the same magnitudes for PWM.
A. Mertens, V. Ganesan
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A novel method for preventing mal-operation of the zero-sequence directional component
12th IET International Conference on AC and DC Power Transmission (ACDC 2016), 2016Zero-sequence directional components of the healthy line would incorrectly discriminate the fault direction, causing mal-operation of the pilot zero-sequence directional protection, due to the influence of mutual inductance between lines under weak current and strong magnetic situations.
H.Y. Xu +4 more
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A Unified SVM Algorithm for Multilevel Converter and Analysis of Zero Sequence Voltage Components
IECON 2006 - 32nd Annual Conference on IEEE Industrial Electronics, 2006Space vector modulation (SVM) is widely used in three phase converters. This paper presents a novel SVM algorithm in three phase coordinate system which is very simple to implement. In this algorithm, the role of the zero sequence component in SVM is studied, and the switching states and duty ratios are calculated straightforwardly without vector ...
Wang Chenchen, null Li Yongdong, Xiao Xi
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A New Fault Line Selection Method Based on Zero-Sequence Active Component
2010 International Conference on Electrical and Control Engineering, 2010a new fault line selection method based on the elimination of unbalanced current of zero-sequence active power is proposed by analyzing the principle of active power method and its inaccuracy. The amplitude and phase of real zero-sequence currents can be calculated by the method and the effect of unbalanced current is eliminated.
Wang Chonglin +3 more
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A general SVM algorithm for multilevel converters considering zero-sequence component control
31st Annual Conference of IEEE Industrial Electronics Society, 2005. IECON 2005., 2005Space vector modulation (SVM) scheme plays a significant role in high-voltage high-power applications of multilevel converters for its good performance. This paper presents a novel general SVM algorithm for multilevel converters. It includes two parts: one is control of fundamental component of three-phase outputs corresponding to reference vector; the
null Yongdong Li +2 more
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2007 7th International Conference on Power Electronics and Drive Systems, 2007
A minimization problem for the instantaneous active and reactive currents give the optimal solution for the three-wire three-phase systems. This basic solution is simple to implement, but posing practical issues when it is applied to a four-wire three-phase system.
E. Pashajavid +2 more
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A minimization problem for the instantaneous active and reactive currents give the optimal solution for the three-wire three-phase systems. This basic solution is simple to implement, but posing practical issues when it is applied to a four-wire three-phase system.
E. Pashajavid +2 more
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2016 7th India International Conference on Power Electronics (IICPE), 2016
The fault current at a particular node in microgrid system varies depending upon its grid connected and islanded mode of operations. In this scenario microgrid the function of microgrid central protection unit becomes challenging to maintain its simplicity and reliability during protection coordination.
Manjeet Singh, Prasenjit Basak
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The fault current at a particular node in microgrid system varies depending upon its grid connected and islanded mode of operations. In this scenario microgrid the function of microgrid central protection unit becomes challenging to maintain its simplicity and reliability during protection coordination.
Manjeet Singh, Prasenjit Basak
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International Journal of Electronics, 2017
ABSTRACTThis paper describes the design of a dynamic voltage restorer (DVR) that can simultaneously protect several sensitive loads from voltage sags in a region of an MV distribution network. A novel reference voltage calculation method based on zero-sequence voltage optimisation is proposed for this DVR to optimise cost-effectiveness in compensation ...
Le Jian +3 more
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ABSTRACTThis paper describes the design of a dynamic voltage restorer (DVR) that can simultaneously protect several sensitive loads from voltage sags in a region of an MV distribution network. A novel reference voltage calculation method based on zero-sequence voltage optimisation is proposed for this DVR to optimise cost-effectiveness in compensation ...
Le Jian +3 more
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2010 IEEE International Conference on Power and Energy, 2010
Distance relays are subject to fail to detect some earth faults since the fault resistance is usually much more in the earth faults rather than the ph-ph faults. Typically a traditional zero-sequence-based method is used to detect a high-resistance earth fault. However, this method fails to detect some high-resistance earth faults.
Amin Samanfar, Behnam Mahamedi
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Distance relays are subject to fail to detect some earth faults since the fault resistance is usually much more in the earth faults rather than the ph-ph faults. Typically a traditional zero-sequence-based method is used to detect a high-resistance earth fault. However, this method fails to detect some high-resistance earth faults.
Amin Samanfar, Behnam Mahamedi
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Zero-sequence components in unit-connected generator with ungrounded neutral during ground-faults
PowerCon 2000. 2000 International Conference on Power System Technology. Proceedings (Cat. No.00EX409), 2002An analysis of voltage zero-sequence components in a generator during normal operation (pre-fault conditions) and during ground-faults in stator winding of generator with ungrounded neutral is presented. The changes in voltage zero-sequence components of fundamental frequency and 3rd harmonic during generator pre-fault conditions, ground-faults in ...
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