不同激励信号驱动下压电泵的输出性能

Output performance of piezoelectric pump driven by different excitation signals

为了研究不同的激励信号驱动下无阀压电泵的输出性能,以锥形流管无阀压电泵为研究对象,根据激励信号的数学表达式理论分析了常见的正弦波、方波和三角波等信号激励下的压电振子振动特性,并以去离子水为传输介质,试验研究不同信号激励下的压电泵的液体传输特性和压电振子的振动特性.试验结果表明:锥形流管无阀压电泵在3种不同激励信号下,随着驱动频率的增大,其流量均呈现先增大后减小的变化趋势;当驱动电压为单峰100 V,频率9 Hz时,方波信号驱动产生的泵流量最大,为1.86 g/min;三角波信号驱动产生的泵流量最小,为1.29 g/min.并且,方波激励下的压电振子振幅最大,为64.82μm;三角波激励下的振子振幅最小,为52.29μm.同时,由泵流量与压电振子振幅曲线可知,振幅并非影响压电泵输出流量的唯一因素.综合对比可发现,方波信号驱动下的压电泵输出性能最强,但振动噪声较大,影响使用.

To investigate output performance of valveless piezoelectric pumps driven by different excitation signals,a valveless piezoelectric pump with cone-shaped tubes was used in the paper. According to the mathematical equations of commonly used driving signals,such as sinusoidal,square and triangular waves,the vibration characteristics of the vibrator driven by these signals were analyzed. Then the performance of liquid transport in the pump and the vibration characteristics were measured using deionized water. The experimental results show that the pump flow rate increases initially and then decreases with increasing driving frequency of these excitation signals. The maximum pump flow rate is1. 86 g/min for the square wave（ 9 Hz,100 V）,and the minimum flow rate is 1. 29 g/min for the trian-gular wave. The maximum amplitude of the piezoelectric vibrator is 64. 82 μm for the square wave,and the minimum amplitude is 52. 29 μm for the triangular wave. It was noted that the pump flow rate versus piezoelectric vibrator amplitude curves show the amplitude is not the only factor affecting the output flow of the pump. After a comprehensive comparison,it is found that the piezoelectric pump driven by square wave has the best output performance,but its vibrator is noisier in operation,thus the pump application will be limited inevitably.