Development of fuzzy logic based temperature controller for dialysate preparation system

Preparing the dialysate temperature to the desired level is a complicated task, since it has a large degree of time delay and nonlinear behaviour. In this work, embedded system for dialysate temperature controller was developed. It is based on implementation of fuzzy logic controller software on STM32 F4 development kit which consits of ARM Cortex M4F microcontroller. The dialysate temperature was controlled by varying the firing angle of the triac which is connected to the heater. The K-type thermocouple which is connected to AD595CQ was read and compared with the desire dialysate temperature. The fuzzification process was conducted prior to activate the fuzzy inference process. The power of the heater was adjusted based on the output of the inference process until the desired water temperatur was achieved. The system had been sucessfully demonstrated for controlling the dialysate temperature.