Dialysate conductivity regulation is the most important factor behind a successful dialysis. In this study, a new Immune-LQI controller was designed to regulate the dialysate conductivity. Linear Quadratic Integrator (LQI), Immune Control (IC), Fuzzy Logic (FL) and Genetic Algorithm (GA) were used. The new controller combines LQI and IC methods, and the IC gains were adjusted using FL and GA. For the purpose of comparison, a number of controllers (Proportional Integral Derivative (PID), LQI, and LQI-PID) were designed. The results showed that Immune-LQI controller was the best as it gave a 10% improvement in rise time, 66% in overshoot, and 42.7% in settling time, when compared with LQI.
