Research Power Control of Ultrasonic Power Supply
|School||Henan University of Science and Technology|
|Course||Control Theory and Control Engineering|
|Keywords||Ultrasonic Power Supply Phase Shift Control Frequency Tracking Phase Locked Loop Fuzzy Control Matching Network|
In recent years, ultrasonic cleaning technology has been widely applied in manyfields because of its low cost, high degree of automation and good cleaning effect.Ultrasonic power supply is the core part of the ultrasonic cleaning machine. Therefore,needs of a new generation ultrasonic power supply are becoming more and moreurgent. In this paper, the analysis and summary based on previous studies areintroduced. At the same time, relevant information and literature are consulted.Combining with fuzzy control technology, phase-locked loop(PLL) technology, soft-switching technology and phase shift PWM technology, a new ultrasonic power supplywhich used DSP control chip TMS320LF2407A as the core is researched.The main content of this article includes:(1) In aspect of power inverter selection,in consideration of the issues of power mainly for the high-frequency band, seriesresonant inverter is choosed in this artical through the analysis and comparison of theseries resonant inverter and parallel resonant inverter.(2) In aspect of power control,PS-PWM power adjustment technology is used through analyzed and compared withseveral representative power adjustment. Moreover, using soft switch technology canreduce switching losses. The power method can achieve the continuous adjustment ofthe output power of the ultrasonic power supply.(3) In the aspect of frequencytracking, in order conquer the shortcomings of traditional frequency tracking method,a novel requency tracking control strategy based on the fuzzy control combined withdigital phase-locked loop (Fuzzy-PLL) has been proposed, which searches the loadresonance frequency through the fuzzy control and utilizes accuracy of phase-lockedloop frequency tracking circuit to realize frequency automatic tracking and alwaysensure transducer load work on the resonant frequency.(4) Meanwhile, a improvedseries resonant matching network is used based on detailed analysis of sevseal tuningscheme, which meets the system requirements for impedance matching and improvesthe adaptive capacity of the matching circuit on the transducer changes in electricalparameters. The last, simulation models based on the analysis of ultrasonic power powercontrol and frequency tracking have been simulated. Experimental results show thatthe design could achieve continuous adjustment of output power and frequencytracking automatically. The experiment proved high reliability, good performance, andadaptability. In addition, switching losses are reduced and the efficiency of the systemis improved with the use of the soft-switch technology. It has brightness way in future.