Research And Implementation Of Temperature Control System For Magnetic Liquid Hyperthermia

Magnetic fluid hyperthermia is a kind of new therapy that uses alternating magnetic field to induce induction heating to treat tumor.The principle is to heat the tissue by heating the magnetic liquid introduced into the tissue,so that the temperature within the organization can not only kill cancer cells,but also can not destroy the normal tissue to achieve the requirements of cancer treatment.And to achieve precise control of the temperature of the magnetic liquid has always been a difficulty in the study of hyperthermia.Magnetic fluid thermotherapy is also required to achieve 43℃ constant temperature control,the lesion will be heated to about 430C and continued for some time.Temperature is the most important factor to influence the effect of magnetic fluid hyperthermia.Therefore,In the course of hyperthermia,the ability to design a reliable,high-precision temperature control system has become the key to the effect of hyperthermia.In this paper,a magnetic fluid hyperthermia temperature control system based on fuzzy neural network-PID algorithm is proposed,and its related contents are studied.First of all,according to the study of magnetic fluid hyperthermia theory and related technologies of temperature control,it is known that the controlled object in the magnetic liquid hyperthermia has the features of nonlinear and large hysteresis.In this paper,fuzzy neural network-PID control algorithm for magnetic fluid hyperthermia is selected.Combining the advantages of traditional PID,fuzzy theory and artificial neural network theory,the closed-loop control of tumor thermotherapy is achieved by controlling the output power of inverter circuit.Through the MATLAB simulation,the experimental results show that the fuzzy neural network-PID control algorithm has good self-learning ability and self-adaptability,and has high accuracy in temperature control and maintenance.Secondly,according to the requirement of therapeutic effect of magnetic fluid hyperthermia,the function circuit of temperature control system for hyperthermia was designed by using two-stage control system of upper computer and lower computer.Firstly,the function circuit of the temperature control system is designed,then the temperature collecting circuit and the temperature real-time display platform are set up,finally the corresponding program are written.The host computer mainly realizes the temperature real-time display function,the lower position machine takes the monolithic integrated circuit as the core,realizes the function of alternating magnetic field,the temperature gathering,the D/A conversion and so on.Finally,the temperature control system is set up to control and adjust the temperature to ensure that the temperature of the magnetic liquid is always within the scope of hyperthermia.It is shown that the experimental results can meet the design requirements well by comparing with the simulation results.