Two delay-based nonlinear controllers and their tuning methods

This work studies two delay-based nonlinear controllers and their tuning methods aimed to servodrive control. The first controller is the Cascade Nonlinear Proportional Integral Retarded (CNPIR) control law, which is composed of two nested loops. The inner loop is regulated through an Integral Retarded (IR) Controller and the outer loop uses a nonlinear proportional (NP) controller. The second controller, which is called the Modified Nonlinear Proportional Integral Retarded (MNPIR) controller is a structural modification of the original Proportional Integral Retarded PIR controller, and also has an inner-outer loop structure. The topology of both controllers is presented as well as their tuning methodologies. Numerical results allow assessing the performance of these controllers when applied to a servodrive model.