Results 251 to 260 of about 5,589,178 (285)
Some of the next articles are maybe not open access.
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
openaire +1 more source
An Area-Minimum Control Method Using Zero-Sequence Components and Current Deviation Term for Hvdc
2022A B S T R A C TIn the converter firing control system of HVDC project, the Area-Minimum (AMIN) control calculates the commutation margin of each converter valve in real time. Once the commutation margin of a converter valve is less than the minimum limit, the next converter valve is fired in advance to avoid commutation failure.
Juanjuan WANG +6 more
openaire +1 more source
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
openaire +1 more source
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
openaire +1 more source
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
openaire +1 more source
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
openaire +1 more source
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
openaire +1 more source
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
openaire +1 more source
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
openaire +1 more source
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
openaire +1 more source
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 ...
openaire +1 more source
Journal of the Korean Institute of Illuminating and Electrical Installation Engineers, 2013
The dynamic voltage restorer (DVR) is an effective protection device for wind turbine generators based on doubly-fed induction generator (DFIG) that is operated under unbalanced voltage dip conditions. The compensating voltages of the DVR depend on the voltage dips and on the influence of the zero sequence component. The zero sequence component results
Quach Ngoc Thinh +3 more
openaire +1 more source
The dynamic voltage restorer (DVR) is an effective protection device for wind turbine generators based on doubly-fed induction generator (DFIG) that is operated under unbalanced voltage dip conditions. The compensating voltages of the DVR depend on the voltage dips and on the influence of the zero sequence component. The zero sequence component results
Quach Ngoc Thinh +3 more
openaire +1 more source
IEEE Transactions on Power Electronics, 2015
This paper focuses on the development of an online method for diagnosing high-resistance connection (HRC) in delta-connected permanent magnet synchronous machine (PMSM) using zero-sequence current component (ZSCC). The development of this method begins with the establishment of the mathematic model of the PMSM with the HRC.
Jun Hang +3 more
openaire +1 more source
This paper focuses on the development of an online method for diagnosing high-resistance connection (HRC) in delta-connected permanent magnet synchronous machine (PMSM) using zero-sequence current component (ZSCC). The development of this method begins with the establishment of the mathematic model of the PMSM with the HRC.
Jun Hang +3 more
openaire +1 more source
2014 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC), 2014
Transformers neutral grounding accessing small reactance is an effective measure to restrain short circuit current in 500kV power grid. But accessing small reactance will bring changes to the zero-sequence parameters of system. The relay protection, especially the main transformer protection and transmission line protection nearby will be affected and ...
Li Xiao-hua +4 more
openaire +1 more source
Transformers neutral grounding accessing small reactance is an effective measure to restrain short circuit current in 500kV power grid. But accessing small reactance will bring changes to the zero-sequence parameters of system. The relay protection, especially the main transformer protection and transmission line protection nearby will be affected and ...
Li Xiao-hua +4 more
openaire +1 more source