基于电流搜索与锁相技术的超声碎石电源频率扫描/跟踪

Research on Frequency Scanning and Tracking of Ultrasonic Lithotripsy Power based on Current Search and Phase-Locked Technology

针对超声碎石治疗过程中因负载突变和换能器参数变化等因素导致的频率漂移和失锁问题,提出了一种基于电流搜索与锁相技术复合的频率扫描/跟踪策略,采用基于DDS技术的电流搜索法进行粗扫描/跟踪,以大步长快速扫描/跟踪到超声碎石振动系统的谐振频率附近,转为基于锁相技术的精扫描/跟踪,最终实现超声碎石振动系统谐振频率的快速精确扫描/跟踪.根据该频率扫描/跟踪方法研制超声碎石电源,并对其扫描/跟踪性能进行测试,测试结果表明,运用这种控制方法的超声碎石电源具有频率扫描/跟踪准确、速度快等优点.

Aiming at frequency drift and loss of lock problem caused by mutation load,and changes of transducer parameter and others in the process of ultrasonic lithotripsy,the composite of frequency scanning and tracking strategy based on current searching and phase-locked technique is presented. The method of current search based on DDS technology for coarse scanning and tracking is used to scan and track quickly to reach the resonant frequency of ultrasonic lithotripsy vibration system by large step. Then fine scanning and tracking based on phase-locked technology is applied to achieve the rapid,and accurate scanning and tracking in resonant frequency of the ultrasonic lithotripsy vibration system. Ultrasonic lithotripsy power is manufactured according to this frequency scanning and tracking method. Performance testing of the ultrasonic lithotripsy power is completed,which shows that while frequency scanning and tracking,this kind of ultrasonic lithotripsy power has the advantages of accuracy and celerity.