Application of the discrete-time structured singular value for DC-DC converters

This paper considers the application of the discrete-time structured singular value to assess the robustness of systems subject to real parametric uncertainties. Since the associated uncertainty set is strictly real, the resulting mu bounds may be discontinuous irrespective of the fineness of the frequency sweep. It is therefore necessary to seek other more reliable methods of test. One such method detailed is a discrete robust stability state-space test that is not dependent on a frequency sweep. It is shown that this is a discrete skewed structured singular value problem. For illustration purposes, a robustness analysis using both a frequency sweep and state-space transformation is performed on a forward converter with a real parameter uncertainty. The results are detailed and critically assessed.