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An Adaptive Feed-Forward Phase Locked Loop for Grid Synchronization of Renewable Energy Systems under Wide Frequency Deviations

Journal Article


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Abstract


  • Synchronization is a crucial problem in the grid-connected inverter’s control and operation.

    A phase-locked loop (PLL) is a typical grid synchronization strategy, which ought to have a high

    resistance to power system uncertainties since its sensitivity influences the generated reference signal.

    The traditional PLL catches the phase and frequency of the input signal via the feedback loop filter

    (LF). In general, to enhance the steady-state capability during distorted grid conditions generally,

    a filter tuned for nominal frequency is used. This PLL corrects large frequency deviations around

    the nominal frequency, which increases the PLL’s locking time. Therefore, this paper presents an

    adaptive feed-forward PLL, where the input signal frequency and phase under large frequency

    deviations are tracked precisely, which overcomes the above-mentioned limitations. The proposed

    adaptive PLL consists of a feedback loop that reduces the phase error. The feed-forward loop

    predicts the frequency and phase error, and the frequency adaptive FIR filter reduces the ripples in

    output, which is due to input distortions. The adaptive mechanism adjusts the gain of the filter in

    accordance with the supply frequency. This reduces the phase and frequency error and also decreases

    the locking time under wide frequency deviations. To verify the effectiveness of the proposed

    adaptive feed-forward PLL, the system was tested under different grid abnormal conditions. Further,

    the stability analysis has been carried out via a developed prototype test platform in the laboratory.

    To bring the proposed simulations into real-time implementations and for control strategies, an Altera

    Cyclone II field-programmable gate array (FPGA) board has been used. The obtained results of the

    proposed PLL via simulations and hardware are compared with conventional techniques, and it

    indicates the superiority of the proposed method. The proposed PLL effectively able to tackle the

    different grid uncertainties, which can be observed from the results presented in the result section.

UOW Authors


  •   Kathiresan, Aravind Chellachi. (external author)
  •   PandiaRajan, Jeyaraj (external author)
  •   Sivaprakash, Asokan (external author)
  •   Babu, Thanikanti Sudhakar. (external author)
  •   Islam, Md Rabiul

Publication Date


  • 2020

Citation


  • A. Chellachi. Kathiresan, J. PandiaRajan, A. Sivaprakash, T. Sudhakar. Babu & M. Islam, "An Adaptive Feed-Forward Phase Locked Loop for Grid Synchronization of Renewable Energy Systems under Wide Frequency Deviations," Sustainability, vol. 12, pp. 7048-1-7048-15, 2020.

Scopus Eid


  • 2-s2.0-85090393682

Ro Full-text Url


  • https://ro.uow.edu.au/cgi/viewcontent.cgi?article=5348&context=eispapers1

Ro Metadata Url


  • http://ro.uow.edu.au/eispapers1/4319

Start Page


  • 7048-1

End Page


  • 7048-15

Volume


  • 12

Place Of Publication


  • Switzerland

Abstract


  • Synchronization is a crucial problem in the grid-connected inverter’s control and operation.

    A phase-locked loop (PLL) is a typical grid synchronization strategy, which ought to have a high

    resistance to power system uncertainties since its sensitivity influences the generated reference signal.

    The traditional PLL catches the phase and frequency of the input signal via the feedback loop filter

    (LF). In general, to enhance the steady-state capability during distorted grid conditions generally,

    a filter tuned for nominal frequency is used. This PLL corrects large frequency deviations around

    the nominal frequency, which increases the PLL’s locking time. Therefore, this paper presents an

    adaptive feed-forward PLL, where the input signal frequency and phase under large frequency

    deviations are tracked precisely, which overcomes the above-mentioned limitations. The proposed

    adaptive PLL consists of a feedback loop that reduces the phase error. The feed-forward loop

    predicts the frequency and phase error, and the frequency adaptive FIR filter reduces the ripples in

    output, which is due to input distortions. The adaptive mechanism adjusts the gain of the filter in

    accordance with the supply frequency. This reduces the phase and frequency error and also decreases

    the locking time under wide frequency deviations. To verify the effectiveness of the proposed

    adaptive feed-forward PLL, the system was tested under different grid abnormal conditions. Further,

    the stability analysis has been carried out via a developed prototype test platform in the laboratory.

    To bring the proposed simulations into real-time implementations and for control strategies, an Altera

    Cyclone II field-programmable gate array (FPGA) board has been used. The obtained results of the

    proposed PLL via simulations and hardware are compared with conventional techniques, and it

    indicates the superiority of the proposed method. The proposed PLL effectively able to tackle the

    different grid uncertainties, which can be observed from the results presented in the result section.

UOW Authors


  •   Kathiresan, Aravind Chellachi. (external author)
  •   PandiaRajan, Jeyaraj (external author)
  •   Sivaprakash, Asokan (external author)
  •   Babu, Thanikanti Sudhakar. (external author)
  •   Islam, Md Rabiul

Publication Date


  • 2020

Citation


  • A. Chellachi. Kathiresan, J. PandiaRajan, A. Sivaprakash, T. Sudhakar. Babu & M. Islam, "An Adaptive Feed-Forward Phase Locked Loop for Grid Synchronization of Renewable Energy Systems under Wide Frequency Deviations," Sustainability, vol. 12, pp. 7048-1-7048-15, 2020.

Scopus Eid


  • 2-s2.0-85090393682

Ro Full-text Url


  • https://ro.uow.edu.au/cgi/viewcontent.cgi?article=5348&context=eispapers1

Ro Metadata Url


  • http://ro.uow.edu.au/eispapers1/4319

Start Page


  • 7048-1

End Page


  • 7048-15

Volume


  • 12

Place Of Publication


  • Switzerland