增量式模糊PI控制超声手术刀振动频率的研究  

Study on incremental fuzzy PI tracking of ultrasonic scalpel vibration frequency

作　　者：魏鹏程 周光银 邬云杰 何苗[1] WEI Pengcheng;ZHOU Guangyin;WU Yunjie;HE Miao(Chongqing University of Technology,Chongqing 400054,China;Chongqing University,Chongqing 400044,China)

机构地区：[1]重庆理工大学,重庆400054 [2]重庆大学,重庆400044

出　　处：《声学技术》2024年第6期816-823,共8页Technical Acoustics

基　　金：重庆理工大学研究生教育高质量发展行动计划资助成果(gzlcx20233421);重庆市教育委员会在渝高校与中国科学院所属院所合作项目(HZ2021011)。

摘　　要：在超声波换能器的谐振系统中,传统的频率跟踪方法由于启动时间长、工作频率带宽窄造成系统的实时性不理想。因此,文章提出了通过--LC匹配网络中电流和电压的相位角变化来反映系统的谐振频率失调情况,并根据相位角的变化匹配谐振频率实现对换能器的频率跟踪的方法,并采用模糊控制思想,改进固定增益比例积分(proportional integral,PI)控制策略,减少了超调量和系统响应时间。利用Matlab软件进行了模糊PI的在线仿真,以相位角大小和相位角随时间变化率为模糊PI输入,谐振频率为输出。模糊PI输出PI控制器所需的K_(p)和K_(i)变化量实现自适应改变PI控制器输出,自适应改变谐振频率。仿真及实验结果表明,电流电压相位角可以在有效时间内追至0°,PI控制的超调量可以有效减少,该方法使得整个系统获得更好的频率跟踪效果。In the resonant system of ultrasonic transducer,the traditional frequency tracking method is unsatisfactory in real time due to the long startup time and the narrow operating frequency bandwidth.Therefore,a frequency tracking method for the transducer is proposed by real-time monitoring the phase angle changes of the current and voltage in the LC matching network to reflect the resonance frequency misalignment of the system and then by changing the phase angle to match the resonance frequency of the system and realize frequency tracking of the transducer.The fuzzy proportional integral(PI)control idea is used to improve the fixed gain PI control strategy,which reduces the amount of overshoot and the system response time.Online simulation of fuzzy PI is carried out by using Matlab,the phase angle and its change rate over time are taken as the fuzzy PI input and the resonance frequency as the output.The fuzzy PI outputs the K_(p) and K_(i) changes required by the PI controller to realize adaptive changes of the PI controller output and the resonant frequency.Simulation and experimental results show that the current and voltage phase angles can be traced to 0°in effective time,the overshoot of PI control can be effectively reduced,and this method enables the whole system to achieve better frequency tracking effect.

关 键 词：超声换能器 谐振频率跟踪 LC匹配 模糊PI控制 

分 类 号：TP273.4[自动化与计算机技术—检测技术与自动化装置] O429[自动化与计算机技术—控制科学与工程]