The Experts below are selected from a list of 16140 Experts worldwide ranked by ideXlab platform

Bruno De Kelper - One of the best experts on this subject based on the ideXlab platform.

  • modeling and real time simulation of Internal Faults in synchronous generators with parallel connected windings
    IEEE Transactions on Industrial Electronics, 2007
    Co-Authors: L A Dessaint, N Fallati, Bruno De Kelper
    Abstract:

    In large synchronous generators, the stator windings are usually parallel-connected in order to increase the machine current capacity. In analysis and modeling, the parallel windings are usually lumped into one equivalent stator winding since equal currents flow in these windings. However, when an Internal Fault occurs in the windings, the symmetry between the parallel windings is broken and different currents will flow in the parallel windings since unsymmetrical magnetic linkage may exist between the stator windings. The aim of this paper is to present a simulation model to investigate the Internal Fault currents of large synchronous generators with parallel-connected windings. This model is based on a modified winding function theory that takes into account all space harmonics. Moreover, the calculation of the machine inductances is made easier by the use of the machine electrical parameters instead of the geometrical ones. The simulation results illustrate the existence of different currents in parallel windings in the case of Internal Faults. Results are given for an implementation of the Internal Fault model in a real-time simulator of large power networks

L A Dessaint - One of the best experts on this subject based on the ideXlab platform.

  • modeling and real time simulation of Internal Faults in synchronous generators with parallel connected windings
    IEEE Transactions on Industrial Electronics, 2007
    Co-Authors: L A Dessaint, N Fallati, Bruno De Kelper
    Abstract:

    In large synchronous generators, the stator windings are usually parallel-connected in order to increase the machine current capacity. In analysis and modeling, the parallel windings are usually lumped into one equivalent stator winding since equal currents flow in these windings. However, when an Internal Fault occurs in the windings, the symmetry between the parallel windings is broken and different currents will flow in the parallel windings since unsymmetrical magnetic linkage may exist between the stator windings. The aim of this paper is to present a simulation model to investigate the Internal Fault currents of large synchronous generators with parallel-connected windings. This model is based on a modified winding function theory that takes into account all space harmonics. Moreover, the calculation of the machine inductances is made easier by the use of the machine electrical parameters instead of the geometrical ones. The simulation results illustrate the existence of different currents in parallel windings in the case of Internal Faults. Results are given for an implementation of the Internal Fault model in a real-time simulator of large power networks

Vishal Kumar - One of the best experts on this subject based on the ideXlab platform.

  • Identification of type of Internal Fault in indirect symmetrical phase shift transformer based on PRN
    2016 IEEE 7th Power India International Conference (PIICON), 2016
    Co-Authors: Shailendra Kumar Bhasker, Manoj Tripathy, Vishal Kumar
    Abstract:

    This paper describes a technique for the detection of type of Internal Fault in an indirect symmetrical phase shift transformer (ISPST). An application of Pattern Recognition Network (PRN) is proposed as a core classifier to identify the type of Internal Fault. Four type of Internal Faults (turn-to-turn (TT), line-to-ground (LG), two line-to-ground (LLG), and three line-to-ground (LLLG)) have been classified. Numerous test cases of Internal Fault in an ISPST have been using PSCAD/EMTDC software. These cases are formed on the basic variation of different parameters of ISPST like Fault inception angle, Fault resistance loading condition and percentage of winding. The accuracy of the proposed technique is evaluated over a large number of cases and it is observed that the technique gives the results with high accuracy even in presence of noise in the signal.

  • wavelet transform based discrimination between inrush and Internal Fault of indirect symmetrical phase shift transformer
    Power and Energy Society General Meeting, 2014
    Co-Authors: Shailendra Kumar Bhasker, Manoj Tripathy, Vishal Kumar
    Abstract:

    The non-sinusoidal inrush current has high magnitude and hence the discrimination from the other operating conditions such as Internal Faults becomes difficult in the protection of a power transformer. This paper proposes an effective method based on wavelet transform for the differentiation between inrush current and Internal Fault current in indirect symmetrical phase shift transformer (ISPST). Conventional Parseval's theorem has been used to calculate the wavelet energy of the differential current and a suitable threshold is decided for the discrimination between inrush and Internal Fault condition of ISPST. Different types of Internal Fault and inrush current conditions under a wide range of switching angle have been considered for the verification of the proposed method in the present simulation study. PSCAD/EMTDC has been utilized as simulation plateform.

S H Hosseinian - One of the best experts on this subject based on the ideXlab platform.

  • a wavelet based method to discriminate Internal Faults from inrush currents using correlation coefficient
    International Journal of Electrical Power & Energy Systems, 2010
    Co-Authors: Behrooz Vahidi, Navid Ghaffarzadeh, S H Hosseinian
    Abstract:

    Abstract In this paper a new method based on discrete wavelet transform and correlation coefficient is presented for digital differential protection. The algorithm includes offline and online operations. In offline operation, discrete wavelet transform is used to decompose typical three-phase differential currents for inrush current. Then an index is defined and computed. The index is based on the sum of the energy of detail coefficients at level 5 of three-phase differential currents at each half cycle. The online operation consists of capturing the three-phase differential currents using 10 kHz sampling rate, decomposing it by db1. Finally, the inrush current and Internal Fault is detected based on correlation coefficients of the computed index of pre-stored typical inrush current and a recorded indistinct signal. The effectiveness of the approach is tested using numerous inrush and Internal Fault currents. Simulations are used to confirm the aptness and the capability of the proposed method to discriminate inrush current from Internal Fault.

Manoj Tripathy - One of the best experts on this subject based on the ideXlab platform.

  • Identification of type of Internal Fault in indirect symmetrical phase shift transformer based on PRN
    2016 IEEE 7th Power India International Conference (PIICON), 2016
    Co-Authors: Shailendra Kumar Bhasker, Manoj Tripathy, Vishal Kumar
    Abstract:

    This paper describes a technique for the detection of type of Internal Fault in an indirect symmetrical phase shift transformer (ISPST). An application of Pattern Recognition Network (PRN) is proposed as a core classifier to identify the type of Internal Fault. Four type of Internal Faults (turn-to-turn (TT), line-to-ground (LG), two line-to-ground (LLG), and three line-to-ground (LLLG)) have been classified. Numerous test cases of Internal Fault in an ISPST have been using PSCAD/EMTDC software. These cases are formed on the basic variation of different parameters of ISPST like Fault inception angle, Fault resistance loading condition and percentage of winding. The accuracy of the proposed technique is evaluated over a large number of cases and it is observed that the technique gives the results with high accuracy even in presence of noise in the signal.

  • wavelet transform based discrimination between inrush and Internal Fault of indirect symmetrical phase shift transformer
    Power and Energy Society General Meeting, 2014
    Co-Authors: Shailendra Kumar Bhasker, Manoj Tripathy, Vishal Kumar
    Abstract:

    The non-sinusoidal inrush current has high magnitude and hence the discrimination from the other operating conditions such as Internal Faults becomes difficult in the protection of a power transformer. This paper proposes an effective method based on wavelet transform for the differentiation between inrush current and Internal Fault current in indirect symmetrical phase shift transformer (ISPST). Conventional Parseval's theorem has been used to calculate the wavelet energy of the differential current and a suitable threshold is decided for the discrimination between inrush and Internal Fault condition of ISPST. Different types of Internal Fault and inrush current conditions under a wide range of switching angle have been considered for the verification of the proposed method in the present simulation study. PSCAD/EMTDC has been utilized as simulation plateform.

  • Identification of Internal Faults in power transformer using symmetrical components and Park's plots
    2009 International Conference on Power Systems, 2009
    Co-Authors: Manoj Tripathy, Asheesh K. Singh
    Abstract:

    A new scheme to discriminate between Internal Fault current and inrush current of power transformer is presented in this paper. In the proposed method, space vector analysis of the differential signal and their time characteristic shapes in park's plane is used as a core classifier to discriminate between magnetizing inrush and Internal Fault of a power transformer. Conventionally, second harmonic component is commonly used for blocking differential relay in power transformer differential protection. A comparison of performance between the proposed method and the conventional harmonic restraint method is also discussed in this paper. Extensive simulation studies have been performed to demonstrate the efficiency of the proposed scheme using PSCAD/EMTDC and MATLAB.