Application of evolution strategy in mixed H∞/H2 control fro a linear brushless DC motor

A novel design and realization of a robust PID controller for a linear brushless DC motor based working platform is developed and its performance is extensively evaluated. A PID control structure is proposed in which only two design parameters, need to be determined. A multiple design specifications directly related to the mixed H_∞/H₂ control are imposed which directly related to the stability robustness and optimal control on the time and frequency domains. An advanced evolution strategy is developed to solve the constrained multi-objective problem; it is a global search algorithm thus avoids trapping into the local minimum. The new design paradigm offers ways to implement simple but robust solutions that cover a wide range of plant perturbation and provides excellent tracking performance. Simulation studies are performed to verify the performance and applicability of our proposed design. The design is also experimentally verified with a linear brushless motor.