Study On Ultrasonic Power Supply Of Frequency Tracking Based On The Single Chip Microcomputer

Because ultrasonic transducer load and external environment change, output frequency and resonant frequency of ultrasonic power supply do not match, so that the cleaning effect is not good. Ultrasonic power supply is the core part of the ultrasonic cleaning machine. In order to achieve its high efficiency and stable work, need to control the work frequency automatic tracking. For that, this paper designs the ultrasonic power supply with maximum output power 600 W, and the working frequency20 k Hz based on PIC16F886 MCU, and realizes the real-time tracking control of the frequency. The main research contents are as follows:Firstly, according to the performance requirements of ultrasonic power supply,ultrasonic power main circuit system is designed. Main circuit system consists of the rectifier filter circuit, inverter circuit, matching circuit, etc. Inverter circuit uses a full bridge inverter. The article has carried on the detailed analysis and design of main circuit system, and simulated each parts of main circuit system by the uses of Multisim software.Secondly, ultrasonic power frequency tracking control scheme is designed. The control method uses the phase-locked loop frequency tracking control with PID control,and C language is applied to write the main program, A/D conversion program, PID control procedure and others.Finally, the ultrasonic power supply control system is designed with the PIC16F866 micro-controller. System mainly includes sampling circuit, drive circuit,single chip computer peripheral circuit, etc. Through the Proteus software, simulation results show that the ultrasonic power supply control system can realize automatic frequency tracking, matches the ultrasonic transducer, meets the design requirements.