Results 251 to 260 of about 1,154,191 (288)

A Method to Reduce the Negative Sequence Current in Electrical Equipments

IEEE Latin America Transactions, 2016
A multiphase optimal power flow method for limiting unbalances of currents in equipments using reactive compensation is proposed in this paper. The equipment modeling is based on current injection method in rectangular coordinates. The method was implemented and the proposed computational tool was developed with Matlab® and Lingo® softwares.
Tatianna Aparecida Pereira Beneteli, Debora Rosana Ribeiro Penido, Leandro Ramos Araujo   +2 more
openaire   +1 more source

Negative-sequence currents for line-to-line faults

Electrical Engineering, 1953
THE RECENT REVISION of the American Standards Association Standard for Rotating Electrical Machinery, C50, short-circuit clause specifies requirements for synchronous generators during 3-phase, line-to-ground, and line-to-line short circuits. A generator operating at rated kilovolt-amperes and power factor, with fixed excitation at 5-per-cent ...
R. F. Lawrence, R. W. Ferguson
openaire   +1 more source

Negative sequence current reduction for generator/turbine protection

Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting, 2002
The authors present a feasible method for negative sequence current reduction at the generator terminal through a special function static VAr compensator (SVC). A specially designed fixed-capacitor thyristor-controlled reactor SVC is used. Computer simulation and laboratory test results show that it can effectively reduce negative sequence current at a
W.-J. Lee, T.-Y. Ho, J.-P. Liu, Y.-H. Liu   +3 more
openaire   +1 more source

Negative sequence quantities-based protection under inverter-based resources Challenges and impact of the German grid code

Electric Power Systems Research, 2020
Inverter-based Resources (IBRs), including Wind Turbine Generators (WTGs), exhibit different negative -sequence fault current characteristics compared to conventional synchronous generators (SGs).
Aboutaleb Haddadi, Ilhan Kocar, Jean Mahseredjian   +2 more
exaly   +2 more sources

Determining negative sequence currents of turbine generator rotors

2009 International Conference on Electrical Machines and Systems, 2009
In parallel to their dynamic duty synchronous generators must be capable of bearing permanently an additional negative sequence current of up to 10% of the rated current according to the IEC 60034–1 standard. On turbine generators this does not only charge the damper winding but causes eddy currents and losses in the solid rotor iron in parallel.
T. Bach, D. Wohner, K. Takahashi, K. Hattori, M. Liese, W. Hofmann   +5 more
openaire   +1 more source

Research on Negative-Sequence Electric Current Examination Method

Advanced Materials Research, 2011
This paper based on traditional ip, iq examination's method , introduces one kind of non-phase-locked loop's ip, iq method. this method avoids the mains frequency displacement the influence, causes the examination to be more conveniently. With the MATLAB simulation of software, obtain the satisfactory results, thus proving the usefulness of this method.
Kai Wang, Wen Jin Dai
openaire   +1 more source

A digital distance relay using negative sequence current

IEEE Transactions on Power Delivery, 1990
The configuration and performance of a recently developed digital distance relay using negative sequence current for remote backup protection are described. Since relays for remote backup protection are designed for remote faults, the fault current that is input to the relay is small due to the influence of current distribution factors.
Y. Ohura, T. Matsuda, M. Suzuki, F. Andow, Y. Kurosawa, A. Takeuchi   +5 more
openaire   +1 more source

Harmonic and Negative-Sequence Current Control in an Islanded Multi-Bus MV Microgrid

IEEE Transactions on Smart Grid, 2014
This paper presents a multifunctional control strategy for the autonomous operation of a multi-bus medium voltage (MV) microgrid under nonlinear and unbalanced load conditions. The main objective is to effectively compensate the harmonic currents of nonlinear loads using electronically-coupled distributed generation (DG) units.
Mohsen Hamzeh, Houshang Karimi, Hossein Mokhtari   +2 more
openaire   +2 more sources

Analysis on IIDG's negative-sequence current upon asymmetric fault

2016 China International Conference on Electricity Distribution (CICED), 2016
As a large number of distributed generations (DG) are connected to the distribution network, the fault current of the distribution network has been changed, and the reliable operation of relay protection in the distribution network has been influenced.
Hua Shao, Haobin Zhu, Rong Lin, Guangfu Xu, Qunbing Yu, Chunguang He   +5 more
openaire   +1 more source

Compensation for the negative-sequence currents of electric railway based on SVC

2008 3rd IEEE Conference on Industrial Electronics and Applications, 2008
As a classic unbalanced load, the traction engines of the electric railways result in negative-sequence currents(NSC) in power systems, which cannot be ignored in most cases. SVC is considered as an effective method to reduce or even eliminate NSC, as well as some other power quality problems, such as reactive power compensation.
null Zhu Guiping, null Chen Jianye, null Liu Xiaoyu   +2 more
openaire   +1 more source