用于压电换能器的频率跟踪驱动电路设计

Design of Frequency Tracking Driver of Piezoelectric Transducer

针对新的压电换能器损耗模型理论,设计并实现了跟踪最佳驱动频率的驱动电路。通过测量验证了最佳频率工作点的存在;利用LC滤波电路克服了电流振荡波形引起的干扰;对换能器进行阻抗匹配设计;通过数字锁相电路,结合FPGA多线程工作模式,实现了最佳频率跟踪。实验结果表明:在新的频率跟踪系统下,换能器的发热量降低为原来的一半,相较于定频系统运行更加稳定。

This paper presents a optimal driving frequency tracking system of piezoelectric transducers which have new theoretical model.The optimum driving frequency principle of piezoelectric transducers is verified by testing the frequency.the driving circuit is designed for the frequency.The LC filter is used to overcome the interference caused by oscillation waveform.The matching impedance circuit of the transducer is designed.The optimal frequency tracking is achieved by digital phase-locked circuit and FPGA.The results show that Under the new frequency tracking system,the rise of temperature of the transducer is reduced to half of rising temperature without the new frequency tracking system.The new system is more stable than the fixed frequency system.