基于开关电容能量球的低噪声超声测距仪的研究

本文研制了一种新型的基于开关电容的低噪声超声波测距仪，相比现有的变压器驱动测距仪，它采用一种电容充放电原理的能量球自适应驱动原理，通过能量球内部快速电子开关切换，利用电路谐振原理激励出比储能电容电压高出3～5倍的能量球驱动电压，对超声波探头进行驱动。该能量球具有体积小、噪声低的特点。根据该原理研制的超声波测距仪，在污水厂进行了超声波测距的对比试验。结果表明，该仪表的能量球驱动方式相比变压器驱动方式，量程提高近20％，信噪比提高18．5dB，适用于恶劣工况。

Study of the lower noise energy drive ball based on the switch capacitor in the ultrasonic level meter

A novel ultrasonic level meter based on the low noise circuit with switching capacitors is presented.Compared with the traditional transformer drive mode,a new drive mode named as the Adaptive Energy Drive Ball (AEDB) was adopted,which is based on the charging and discharging principle of the capacitors.With the rapid electronic switching,the drive voltage of the AEDB is 3~5 times higher than the voltage in the reservoir capacitors at the resonant frequency point,which can stimulate the transducer and features small size and low noise.The new ultrasonic level meter based on the AEDB was tested and compared with the transformer mode tester in a wastewater plant.The results show that the measurement range is increased by about 20% and the SNR is improved by 18.5dB,and the new meter is suitable for worse application environment.