Frequency-adaptive multi-resonant LQG state-feedback current controller for LCL-filtered VSCs under distorted grid voltages Articles uri icon

authors

  • HUERTA SÁNCHEZ, FRANCISCO
  • PÉREZ, JORGE
  • COBRECES ALVAREZ, SANTIAGO
  • Rizo, Mario

publication date

  • November 2018

start page

  • 1

end page

  • 11

issue

  • 11

volume

  • 65

International Standard Serial Number (ISSN)

  • 0278-0046

Electronic International Standard Serial Number (EISSN)

  • 1557-9948

abstract

  • This paper combines the well-known linear quadratic Gaussian (LQG) control and frequency-adaptive resonators and presents a frequency-adaptive multiresonant LQG state-feedback current controller for LCLfiltered voltage-source converters connected to a distorted grid. The paper also provides a design guideline and procedure based on robust control criteria which, in combination with the linear quadratic regulator (LQR) technique, offers flexibility in the control structure and automatizes the design of the controller. The frequencyadaptive resonators, based on second-order IIR resonators and on an on-line tuning algorithm, and the robustness criteria considered for the design process offer robustness in the face of grid voltage disturbances.The controller is evaluated and validated in a 9-kVA VSC setup configured as a rectifier.

keywords

  • digital control; frequency adaptive; gridconnected converter; harmonic mitigation; lcl filter; multiresonant controller; state-space current control