Yazar "Tuohy, Paul Michael" seçeneğine göre listele

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    Investigation of Grid Supply Harmonic Effects in Wound Rotor Induction Machines
    (Ieee, 2018) Sarma, Nur; Tuohy, Paul Michael
    This paper presents an in-depth investigation of the effects of several grid supply harmonic voltages on the stator currents of an example wound rotor induction machine. The observed effects of higher order grid supply harmonics are identified using a finite element time stepping transient model, as well as a time-stepping electromagnetic model. In addition, a number of analytical equations to calculate the spectral content of the stator currents are presented in the paper. The presented equations are validated through comparison with the obtained spectra predicted using the finite element and electromagnetic models. The presented study provides a better understanding of the origin of supply harmonic effects identified in the stator currents of the example wound rotor induction machine. Furthermore, the study helps to understand the effects of higher order supply harmonics on the harmonic emissions of an example wound rotor induction machine.
  • Küçük Resim
    Öğe
    Modeling, Analysis, and Validation of Controller Signal Interharmonic Effects in DFIG Drives
    (Ieee-Inst Electrical Electronics Engineers Inc, 2020) Sarma, Nur; Tuohy, Paul Michael; Djurovic, Sinisa
    This paper presents the development of a doubly fed induction machine (DFIG) harmonic model in matlab/Simulink, which is used to examine the spectral content of DFIG controller signals and improve the understanding of their behavior and spectral nature. The reported DFIG harmonic model has the capability of representing the effects of higher order time and space harmonics and thus, allows detailed analysis of the controller signals embedded spectral effects. The model consists of a wound rotor induction machine (WRIM) harmonic model coupled with a stator flux oriented controller model. The WRIM space harmonic effects are represented using the conductor distribution function approach to enable the calculation of winding inductances as a harmonic series. In addition, analytical expressions are derived to define the possible spectral content in the controller signals of DFIGs. Both the reported DFIG harmonic model and the analytical expressions are validated by comparison with measurements taken from a purpose built vector-controlled DFIG laboratory test rig. The findings confirm the capability of the developed DFIG harmonic model in representing the controller signals embedded spectral effects, as well as the accuracy of the reported analytical expressions, and enables a much improved understanding of the spectral nature of the DFIG controller signals.