Research on the temperature control methods to a hemodialysis system with large inertia and hysteresis

Objective to design a temperature control system for hemodialysis machine. Hemodialysis is a complex process involving multiple components, whereas dialysate temperature is the core performance index, the current control methods are mostly based on experience or fuzzy PID. This article attempted to model accurately the main process. According to the large inertia, hysteresis characteristics of the system, we proposed 3 kinds of control schemes. By comparing, energy model predictive control is a best control method. Adjusting the duty cycle of the PWM to control solid-state relay switch time, achieving temperature control. Experimental results show that this method has a highest control precision, meeting the requirement of thermostatic state.