The Experts below are selected from a list of 100746 Experts worldwide ranked by ideXlab platform

Zhen-nan Fan - One of the best experts on this subject based on the ideXlab platform.

Yong Liao - One of the best experts on this subject based on the ideXlab platform.

  • Effect of Damper Winding and Stator Slot Skewing Structure on No-Load Voltage Waveform Distortion and Damper Bar Heat in Large Tubular Hydro Generator
    IEEE Access, 2018
    Co-Authors: Yong Liao, Jun Wang, Xiu-cheng Dong
    Abstract:

    We study the influence of the damper bar pitch, the stator slot skewing degree, and the damper bar number per pole on the no-Load Voltage waveform harmonic distortion factor (HDF) and the damper winding heat of a tubular hydro generator. We implemented 288 different design schemes using a 36-MW fractional-slot tubular hydro generator. The following influence factors were investigated: continuous variation, variation range, variation step, and higher-order harmonics of no-Load Voltage. Thus, the relation among these structure parameters and the HDF, the losses, and the highest temperature of the damper bars is revealed. In addition, the calculated models and results are validated directly by test data, and measures are proposed for their improvement. The present research not only corrected the errors in the related papers we published before, but also provides guidelines for optimizing the no-Load Voltage waveform and decreases the damper bar losses and heat, as well as a more comprehensive, accurate, and effective reference for improving tubular hydro generator design and manufacture.

  • No-Load Voltage Waveform Optimization and Damper Bars Heat Reduction of Tubular Hydrogenerator by Different Degree of Adjusting Damper Bar Pitch and Skewing Stator Slot
    IEEE Transactions on Energy Conversion, 2013
    Co-Authors: Zhen-nan Fan, Li Han, Yong Liao, Li-dan Xie
    Abstract:

    To analyze the influence of no-Load Voltage waveforms and damper bar losses and heat by the damper bar pitch and stator slot skew, finite-element model (FEM) computations are conducted. The calculation models are multislice moving electromagnetic field-circuit coupling model for the hydrogenerator and three-dimensional temperature field FEM for the rotor. This analysis considers the factors such as the rotor motion and the nonlinearity of time-varying electromagnetic field, the anisotropic heat conduction of the rotor core lamination, and the different heat dissipation conditions on the windward and the leeward sides of the poles. Then, the no-Load Voltage waveforms of a 36 MW tubular hydrogenerator are optimized and the damper bar heat at the rated Load is reduced with the design scheme by adjusting the damper bar pitch and the stator slot skew. The results show that the waveforms of the no-Load Voltage are improved and the temperature of damper bars are reduced when reasonably increasing damper bar pitch and skewing stator slots. The calculated results are well coincident with the test data. The research is helpful for improving the design standard and enhancing the operation reliability of the large tubular hydrogenerator and electric network.

Xiu-cheng Dong - One of the best experts on this subject based on the ideXlab platform.

  • Effect of Damper Winding and Stator Slot Skewing Structure on No-Load Voltage Waveform Distortion and Damper Bar Heat in Large Tubular Hydro Generator
    IEEE Access, 2018
    Co-Authors: Yong Liao, Jun Wang, Xiu-cheng Dong
    Abstract:

    We study the influence of the damper bar pitch, the stator slot skewing degree, and the damper bar number per pole on the no-Load Voltage waveform harmonic distortion factor (HDF) and the damper winding heat of a tubular hydro generator. We implemented 288 different design schemes using a 36-MW fractional-slot tubular hydro generator. The following influence factors were investigated: continuous variation, variation range, variation step, and higher-order harmonics of no-Load Voltage. Thus, the relation among these structure parameters and the HDF, the losses, and the highest temperature of the damper bars is revealed. In addition, the calculated models and results are validated directly by test data, and measures are proposed for their improvement. The present research not only corrected the errors in the related papers we published before, but also provides guidelines for optimizing the no-Load Voltage waveform and decreases the damper bar losses and heat, as well as a more comprehensive, accurate, and effective reference for improving tubular hydro generator design and manufacture.

Li-dan Xie - One of the best experts on this subject based on the ideXlab platform.

  • No-Load Voltage Waveform Optimization and Damper Bars Heat Reduction of Tubular Hydrogenerator by Different Degree of Adjusting Damper Bar Pitch and Skewing Stator Slot
    IEEE Transactions on Energy Conversion, 2013
    Co-Authors: Zhen-nan Fan, Li Han, Yong Liao, Li-dan Xie
    Abstract:

    To analyze the influence of no-Load Voltage waveforms and damper bar losses and heat by the damper bar pitch and stator slot skew, finite-element model (FEM) computations are conducted. The calculation models are multislice moving electromagnetic field-circuit coupling model for the hydrogenerator and three-dimensional temperature field FEM for the rotor. This analysis considers the factors such as the rotor motion and the nonlinearity of time-varying electromagnetic field, the anisotropic heat conduction of the rotor core lamination, and the different heat dissipation conditions on the windward and the leeward sides of the poles. Then, the no-Load Voltage waveforms of a 36 MW tubular hydrogenerator are optimized and the damper bar heat at the rated Load is reduced with the design scheme by adjusting the damper bar pitch and the stator slot skew. The results show that the waveforms of the no-Load Voltage are improved and the temperature of damper bars are reduced when reasonably increasing damper bar pitch and skewing stator slots. The calculated results are well coincident with the test data. The research is helpful for improving the design standard and enhancing the operation reliability of the large tubular hydrogenerator and electric network.

  • No-Load Voltage waveform optimization and damper bars heat reduction of tubular hydro-generator by adjusting damper bar pitch and skewing stator slot
    2011 International Conference on Electrical Machines and Systems, 2011
    Co-Authors: Zhen-nan Fan, Li-dan Xie, Guang-hou Zhou
    Abstract:

    Improvement of no-Load Voltage waveform and optimization of damper bars loss and heat are important problems for designing tubular generators and ensuring operation reliability of the generators and electric network. The no-Load Voltage waveforms of a 30MW tubular hydro-generator are optimized and the damper bars heat are reduced with the design scheme which adjust damper bar pitch and skew stator slots, and the computations are implemented and analyzed by multi-slice moving electromagnetic field-circuit coupling model of the hydro-generator and 3D temperature field FE model of the rotor. The results show that the waveforms of the no-Load Voltage are improved observably and the temperature of damper bars are reduced observably when reasonable increasing damper bars pitch and skewing stator slots. The calculation results are coincident well with the test data. The research is helpful for improving design standard and enhancing the operation reliability of the large hydro-generator and electric network.

C V Nayar - One of the best experts on this subject based on the ideXlab platform.

  • dc bus compensation for a sinusoidal Voltage source inverter with wave shaping control
    IEEE Transactions on Industrial Electronics, 2008
    Co-Authors: M C Trigg, C V Nayar
    Abstract:

    This paper presents a study on the effects of different parameters on the dc bus Voltage of a single-phase Voltage-controlled Voltage-source inverter (VCVSI) with conventional Load-Voltage root-mean-square (rms) feedback control and a wave-shaping controller (WSC). It is shown that the Load-Voltage rms feedback control and the WSC require compensation for the fluctuations in the dc bus Voltage caused by the battery and lead-wire resistance and the lead-wire inductance. The dc-bus-Voltage compensation is shown to provide performance improvements, including better Load-Voltage regulation and less Load-Voltage distortion. The mathematical modeling, computer simulations, and experimental results based on a 2-kVA single-phase full-bridge VCVSI are presented.