Automatic QFT controller design comparison with state space feedback

The Quantitative Feedback Theory idea is an interesting concept in the scope of robust controller design and represents an alternative way to the μ-synthesis. Particularly, it allows to obtain controllers less conservative than other control design methods like those based on H_∞ optimisation. Nevertheless the design of automatic loop shaping algorithms is a complex question and remains an open topic. This paper presents an automatic QFT closed loop controller design based on a 2 steps optimisation algorithm, its application to a double resonant DC/DC converter regulation and compares the results with those obtained with an optimal control state space feedback law using switching gains.