A Youla-parameterization Approach for Controller Design based on ESO and 2E-SO Methods for Low Order Benchmarks

The Youla parameterization (also the Q – parametrization) is a modern control design method suitable for both stable and unstable plants. In the design phase systems with electrical drives can be well approximated through low order linear models called benchmarks. For such system it can be advantageous to use control design based on modulus optimum criterion (Modulus Optimum MO-m and Symmetrical Optimum SO-m) or methods derived from this one, such as ESO-m and 2E-SO-m. In addition to the original, classical SO-m, the 2E-SO-m has the advantage of providing a better phase margin and improved robustness. The paper presents briefly the development and tuning solutions of PI and PID controllers based on ESO-m and 2E-SO-m meant for electrical drive systems. Based on these a Youla parameterization interpretation of the methods is given.