HW—1000型非接触式超声波水位计测量误差分析与检验

Measuring Error Analysis and Test of HW-1000 Type Uncontacting Gauge with Ultrasonic Wave

HW－1000型非接触式超声波水位计的工作原理是超声波传播反射原理，测量精度如何主要取决于对空气介质温度这个影响因素的处理方法，另外，对声波往返传播时间间隔的测量也会产生误差．通过对各项误差对总误差的贡献进行分析和计算，得出HW-1000型超声波水位计可采用双目标实时校准法，测量误差仅与校准杆A、B之间的王巨离和声波在传感器往返至校准杆A、B至水面之间的传播时间误差有关．满量程测量误差理论值小于水文测验规范规定的±2cm的要求．并且还可以看出双目标实时校准法不仅与声速无关，而且计时误差引起的各项误差中，有一部分可抵消，从而得到了对总误差的补偿．

The HW-1000 type uncontacting gauge with ultrasonic wave works on the reflecting principle of the ultrasonic propagation. The measurement precision mainly depends on the processing method of the factor-air-medium termprature, additionally, the time measurement of the ultrasonics traveling to and for can lead to error. Through analysing and calculating the contribution of different errors to total error, it has been known that, the real-time correcting method with double aims could be used to the HW-1000 ultrasonic gauge. The measuring error has relations not only with the distance between the correcting poles A and B, but also with the timing error in which the ultrasonic wave travels to and for from the sensor to water surface. The theoretical error under the condition of maximum measures is less than that assigned in the Standard for Hydrometry Norm. It can be seen that, the real-time correcting method with double aims not only has no relation with sonic velocity,but also has a part error counteraction in different errors caused by timing error, so that the total error is compensated.