Development Of Ultrasonic Power Supply Based On Wireless Energy Transfer Technology

Ultrasonic technology is widely used in cleaning,testing and processing fields.Ultrasonic assisted machining has been developed rapidly because of its better performance in processing quality and efficiency for the processing of brittle and hard materials.In the ultrasonic-assisted machining system,the ultrasonic power supply provides energy for the transducer,which is one of the most important components in the ultrasonic system.The wireless energy transmission technology has the characteristics of reliable energy transmission,economy and high upper limit of spindle speed,which has become the research hotspot of rotary ultrasonic machining system.However,the resolver used in the wireless energy transfer technology is loosely coupled,which has large magnetic flux leakage and makes it difficult for the ultrasonic power supply to monitor the working state of the transducer.It is necessary to propose an ultrasonic power source that can monitor the status of the transducer for the wireless energy transmission ultrasonic processing system and study the compensation circuit of the wireless energy transfer transformer to realize the compensation of the transmission effective power.In this thesis,the following researches are carried out on the basis of existing ultrasonic transducers and wireless energy transfer transformers:(1)The hardware system of the ultrasonic power supply device is completely designed.The requirements of the wireless energy transfer ultrasonic machining system are analyzed,and the overall design structure of the separated ultrasonic power supply is determined.Completed the hardware circuit design of full-bridge rectifier circuit,BUCK chopper power regulation circuit,full-bridge inverter circuit,drive control circuit,dead zone generation circuit,feedback sampling circuit and so on.(2)The impedance matching network in the ultrasonic power supply is designed.The structure of the wireless energy transfer system used in this thesis includes a high-frequency transformer,a wireless energy transfer resolver,a transformer compensation circuit and a transducer circuit.In this thesis,the equivalent circuits of transducers and loosely coupled transformers are studied and the corresponding electrical parameters are measured.According to the measured electrical parameters,four compensation methods of SS,SP,PS and PP are studied according to the maximum transfer efficiency and maximum transfer power.Finally,the design of the output high-frequency transformer of the ultrasonic power supply with impedance matching is completed.(3)The software of the ultrasonic power supply device is designed.This thesis designs the control logic of ultrasonic power supply,compared the advantages and disadvantages of various short-distance wireless communication methods and chooses2.4G wireless communication.The frequency tracking control process is designed,including bisection frequency sweep and variable step frequency tracking,and the amplitude control program based on current feedback is designed.Finally,the entire control system design of the ultrasonic power supply device is completed.(4)An experimental platform for ultrasonic power supply testing based on wireless energy transmission is built,the correctness and reliability of the circuit design are verified through experiments,and the circuit is optimized according to the experimental results.Through EDA drawing software,the designed circuit is drawn into a PCB circuit board and produced,and the entire ultrasonic power supply energy supply experimental platform is completed,which verifies that the ultrasonic power supply wireless energy supply system has the functions of frequency tracking and current feedback.In this thesis,a separate ultrasonic power supply is developed which can solve the low energy transmission efficiency of wireless energy transmission ultrasonic processing system and the difficulty of transducer feedback acquisition.It is verified by experiments that the power supply can realize the functions of transducer wireless monitoring and frequency tracking.