A nonlinear PID controller based on fuzzy-tuned immune feedback law

A new nonlinear PID controller is presented in this paper by combining the immune feedback law with conventional PID control. Focusing on the immune feedback mechanism of biological immune systems, we first propose a P-type immune feedback controller. The P-type immune feedback law is tuned online by a fuzzy logic controller. Then we extend it to a PID-type immune feedback controller based on the PID control structure. The effectiveness of this control approach is examined in the control of a third-order plant and a nonlinear plant. Computer simulation results demonstrate that the control performance of the immune-based controller is superior to that of the corresponding linear PID controller