Combined Servo/Regulation Operation of PID Controllers: Performance Considerations and Autotuning Relations

This paper presents a PID tuning technique with the aim to reduce the degradation of the performance for the optimal settings (servo or regulation), when the operating mode of the system is different from the select one for tuning. The above is achieved from the definition of the Performance Degradation concept, that is a way for measuring this kind of loss on both extreme situations of tuning. From this approach, it is looking for an intermediate tuning that improves the overall performance of the control loop and thus reduces the Performance Degradation. Some extra approaches are developed and presented, specially regarding on autotuning and robustness considerations for this PID trade-off tuning technique.