Bode optimal loop shaping with CRONE compensators

Ideal Bode characteristics give a classical answer to optimal loop design for linear time invariant feedback control systems in the frequency domain. This work recovers eight-parameter Bode optimal loop gains, providing a useful and simple theoretical reference for the best possible loop shaping from a practical point of view. The main result of the paper is to use CRONE compensators to make a good approximation and in addition a way for the synthesis of the Bode optimal loop. For that purpose, a special loop structure based on second and third generation CRONE compensators is used. As a result, simple design relationships will be obtained for tuning the proposed CRONE compensator.