Microwave High-temperature Automatic Control System

Microwave can penetrate into material and causes volume heating. It is characterized in uniform heating,low cost, and short processing time. Compared to conventional heating methods,microwave heating greatly reduces the heating time and improves the heating efficiency.Based on the theory of microwave heating in this paper, Microwave heating system was designed in the 2450MHz frequency of the automatic control system from researching the general microwave heating system.The main work is as follows:1.The source of microwave power, microwave transmission system and the heating cavity are introduced from the studying the micowave heating system model. Focus on the control and regulation of the magnetron, the analysis and selection of the waveguide transmission system, the design and simulation of the heating cavity.2.Analysis the advantages and disadvantages of temperature sensor, select the thermocouple as a temperature sensor. And design the specific probe device because of microwave interference and protection of thermocouples.3.The design of hardware is based on C8051F020 single chip, temperature signal is acquisition by single chip from amplification and filtering. The digital to analog converter to control the currernt size, which control the size of the out power of magnetron to achieve the purpose of changing the temperature.4.It consists the bottom and top computer in two parts. The former is written in assembly language, which is the core of the PID algorithm, and realizes the control functions. The latter achieves the design of interface, finishes the real-time display of temperature collection and data storage.