Juan Augusto Paredes Salazar

Juan Augusto Paredes Salazar

I'm a Research Fellow at the University of Michigan with research interests in Guidance, Navigation and Control of UAVs and aerospace systems.

Adaptive Control of Self-Excited Systems

Source of Funding: National Science Foundation (NSF) under grant CMMI 1634709.

The aim of the project is to apply adaptive control algorithms to minimize the oscillatory response of self-excited systems (SES), in particular, gas-turbine combustors, in which the interaction between combustion and acoustics causes thermoacoustic oscillations and may result in flameout, structural fatigue, thermal cycling, failure of combustor components, and poor combustion performance. For this purpose, retrospective cost adaptive control (RCAC) is applied to thermoacoustic systems under extremely limited modelling information and actuator limitations.

The main tasks performed in this project were the following:

  • Developed a methodology to choose RCAC hyperparameters and applied RCAC to a Rijke-tube experiment to test stabilization performance over a range of operating conditions.
  • Developed an extension of RCAC called quasi-static RCAC (QSRCAC) for online optimization applications, and applied it to a physical combustor to obtain operating conditions under which thermoacoustic oscillations are reduced while reaching a specified exit temperature corresponding to a desired flame length.

Papers

  • Self-Excited Dynamics of Discrete-Time Lur’e Systems with Affinely Constrained, Piecewise-C1 Feedback Nonlinearities (More details)
  • Experimental Application of a Quasi-Static Adaptive Controller to a Dual Independent Swirl Combustor (More details)
  • Output-only identification of self-excited systems using discrete-time Lur’e models with application to a gas-turbine combustor (More details)
  • Experimental Implementation of Retrospective Cost Adaptive Control for Suppressing Thermoacoustic Oscillations in a Rijke Tube (More details)
  • Output-Only Identification of Lur’e Systems with Hysteretic Feedback Nonlinearities (More details)
  • Retrospective Cost-Based Extremum Seeking Control with Vanishing Perturbation for Online Output Minimization (More details)
  • Output-Only Identification of Lur’e Systems with Prandtl-Ishlinskii Hysteresis Nonlinearities (More details)
  • Adaptive Stabilization of Thermoacoustic Oscillations in a Rijke Tube (More details)
  • Experimental Investigation of Adaptive Feedback Control on a Dual-Swirl-Stabilized Gas Turbine Model Combustor (More details)
  • Identification of Self-Excited Systems Using Discrete-Time, Time-Delayed Lur’e Models (More details)
  • Design and Characterization of the Dual Independent Swirl Combustor Facility (DISCo) (More details)
  • A Time-Delayed Lur’e model with Biased Self-Excited Oscillations (More details)

Videos

  • Experimental Application of a Quasi Static Adaptive Controller to a Dual Independent Swirl Combustor (Link)
  • Stabilization of Thermoacoustic Oscillations in a Rijke Tube (Link)
  • Identification of Self-Excited Systems Using Discrete-Time, Time-Delayed Lur’e Models (Link)