基于频率跟踪的超声驱动电源研制  

Development of Ultrasonic Driving Power Based on Frequency Tracking

作　　者：彭呈祥 段发阶[1] 蒋佳佳[1] 王金栋 PENG Cheng-xiang;DUAN Fa-jie;JIANG Jia-jia;WANG Jin-dong(State Key Lab of Precision Measuring Technology and Instruments,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津大学精密测试技术及仪器国家重点实验室

出　　处：《电力电子技术》2019年第5期1-5,共5页Power Electronics

基　　金：国家重点研发计划(2017YFF0204800);国家自然科学基金(51775377)~~

摘　　要：针对压电换能器谐振频率漂移的问题,基于双路电流反馈与二分法扫频研制了一款基于频率跟踪的超声驱动电源。根据压电换能器的电路模型,分析了双路电流有效值及其相位差与超声驱动电源串联谐振频率间的关系;利用双路电流信号进行频率反馈控制,在匹配失调、负载变化的情况下仍可精确跟踪换能器的串联谐振频率;利用微处理器实时控制开关电容滤波器的中心频率,实现恒带宽的跟踪滤波器;利用二分法扫频完成对压电换能器串联谐振频率的快速跟踪,完成了原理样机的研制,并进行了相应实验。实验结果表明,所设计的超声驱动电源适应能力强、频率跟踪精度高、跟踪速度快,可在100ms内完成频率的跟踪和锁定,频率跟踪精度可达20Hz。Aiming at the problem of resonant frequency drift of piezoelectric transducer,a frequency tracking ultrasonic driving power source is developed based on double circuit current feedback and bisection frequency sweep frequency.According to the circuit model of the piezoelectric transducer,the relationship between the effective current and the phase difference of the two paths and the resonance frequency of the ultrasonic power supply is analyzed.The frequency feedback control of dual current signals can be used to accurately track the series resonant frequency of the transducer under the condition of mismatch and load changes.The central frequency of the switched capacitor filter is controlled in real time by microprocessor,and the tracking filter with constant bandwidth is realized.Using the dichotomy sweep frequency to complete the fast tracking of the resonant frequency of the piezoelectric transducer.The prototype is completed and the corresponding experiments are carried out.The experimental results show that the ultrasonic driving power supply has high adaptability,high tracking precision and fast tracking speed.The frequency tracking and locking can be completed in 100 ms,and the frequency tracking precision can reach 20 Hz.

关 键 词：超声驱动电源 频率跟踪 双路电流反馈 

分 类 号：TN86[电子电信—信息与通信工程]