基于静态电容补偿的压电换能器锁相环频率跟踪

为解决压电换能器锁相环频率跟踪中存在的跟踪范围狭小、易出现误跟踪和失锁等问题,提出一种基于静态电容补偿的锁相环(PLL)频率跟踪技术:根据电容元件伏安特性对由静态电容造成的不良影响进行补偿,使换能器对锁相环呈现理想的LCR串联谐振回路特性,并结合线性拟合法完成对机械臂电压电流相位差的测量,避免了误跟踪和失锁,实现了较以往更宽频带下的换能器准确跟踪.实验表明:对两个-3 dB带宽分别为120 Hz和663 Hz的换能器,跟踪误差分别为-9 Hz和+28 Hz,跟踪范围可达10 kHz.

A PLL-dependent piezoelectric transducer frequency tracking technique based on static capacitance compensation

To eliminate the phase locked loop's(PLL's) performance degradation of narrow tracking range,mistracking and losing lock in the piezoelectric transducer's frequency tracking,a PLL-dependent transducer frequency tracking technique based on static capacitance compensation was developed.According to the general character of capacitance component,the negative effects from static capacitance were compensated,and thus the transducer could be equivalent to an ideal LCR serial resonance circuit.The mechanical branc...