Minimal Order Compensator Design for a DC-to-DC Power Converter

International Journal of Electrical and Electronics Engineering

© 2020 by SSRG - IJEEE Journal

Volume 7 Issue 6

Year of Publication : 2020

Authors : Sam Jacobs, Richard Tymerski

10.14445/23488379/IJEEE-V7I6P101

How to Cite?

Sam Jacobs, Richard Tymerski, "Minimal Order Compensator Design for a DC-to-DC Power Converter," SSRG International Journal of Electrical and Electronics Engineering, vol. 7,  no. 6, pp. 1-10, 2020. Crossref, https://doi.org/10.14445/23488379/IJEEE-V7I6P101

Abstract:

In this paper we undertake the designs of two reduced order compensators for a (fourth order) switching dc-todc converter. For each, the design methodology of modern control theory is utilized in that optimal controller gains are derived using the linear quadratic regulator (LQR) methodology and state estimators with loop transfer recovery (LTR) are designed to obviate the need for state measurement and to ensure desirable loop gain characteristics. The resulting compensators, in each
case, are further order reduced whereby states with relatively small Hankel singular values are discarded. In the first case, the final third order compensator design is achieved by model reducing the fifth order transfer function of a loop transfer recovered (four state) full order estimator together with (one state) integral control. In the alternative design, model reduction is applied to the transfer function of a loop transfer recovered (three state) reduced order estimator together with (one state)
integral control, resulting in a second order compensator. In terms of implementation, the second design approach is seen as more favorable. A practical implementation is shown and simulated verifying the design efficacy.

Keywords:

linear quadratic regulator (LQR), estimator, loop transfer recovery (LTR), model order reduction, dc-to-dc converter

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