1、微分干扰和工频干扰的消除：

 

　　1.Elimination of differential interference and power frequency interference:

 

　　信号中往往同时存在微分干扰和工频干扰信号，在信号处理电路中的低通滤波往往很难将工频干扰完全滤出。本公司采用同步采样和工频补偿技术，以抑制流量信号电势中混入工频干扰和工频电源频率波动产生工频干扰，并有效除微分干扰。同步采样技术，采样开始时间滞后激磁信号1/4个周期，其采用脉宽为工频周期的偶数倍，消除微分干扰的同时使流量信号电势中工频干扰平均值等于零，以消除工频干扰的影响；工频电源的频率波动补偿是保证频率的动态波动中，激磁电源和采样脉冲得以同步调整，真正实现同步采样技术和同步激磁技术，同步A/D转换，降低了微分干扰和工频干扰的影响。

 

　　There are often differential interference and power frequency interference signals in the signal,and it is often difficult to completely filter the power frequency interference by low-pass filtering in the signal processing circuit.The company adopts synchronous sampling and power frequency compensation technology to suppress the power frequency interference mixed with the power frequency interference and the power frequency power frequency fluctuation in the flow signal potential,and effectively eliminate the differential interference.Synchronous sampling technology,the sampling start time lags behind the excitation signal by 1/4 cycle.The pulse width is an even multiple of the power frequency cycle to eliminate differential interference and make the average power frequency interference in the flow signal potential equal to zero to eliminate power frequency interference.The frequency fluctuation compensation of the power frequency power supply is to ensure that the excitation power supply and the sampling pulse can be adjusted synchronously during the dynamic fluctuation of the frequency.The synchronous sampling technology and the synchronous excitation technology are truly realized,and the synchronous A/D conversion reduces the differential interference and the power frequency.The impact of interference.

 

　　2、零点漂移消除：

 

　　2.Zero drift elimination:

 

　　所谓零点漂移，就是当传感器的输入信号为零时，放大器的输出并不是零。零点漂移的信号会在各级放大的电路间传递，经过多级放大后，在输出端成为较大的信号，由于传感器输出的有用信号较弱，零点漂移就可能将有用信号淹没，使电路无法正常工作。因此为了抑制零点漂移，采用三运放的差动电路输入，实现对大内阻的微弱信号采集，以抑制共模信号的引入。一级放大电路之后采用隔直电容，滤除基线零点漂移，防止直流信号过大，超出A/D转换的输入范围。

 

　　The so-called zero drift means that when the input signal of the sensor is zero,the output of the amplifier is not zero.The zero-point drift signal will be transmitted between the circuits of various levels of amplification.After multi-stage amplification,it will become a larger signal at the output end.Since the useful signal output by the sensor is weak,the zero-point drift may overwhelm the useful signal and make the circuit impossible.normal work.Therefore,in order to suppress the zero-point drift,the differential circuit input of three operational amplifiers is adopted to realize the collection of weak signals with large internal resistance to suppress the introduction of common-mode signals.After the first-stage amplifying circuit,a DC blocking capacitor is used to filter the baseline zero drift to prevent the DC signal from being too large and exceeding the input range of the A/D conversion.

 

　　3、去除干扰的其他措施：

 

　　3.Other measures to remove interference:

 

　　对于由污水流量计传感器的“变压器效应”所产生的正交干扰，采用“变送器调零法”来消除。软件设计方面，采用数字滤波技术与掉电保护技术，软件指令冗余措施，可有效提高输入微处理器数字的可靠性。

 

　　For the orthogonal interference generated by the"transformer effect"of the sewage flowmeter sensor,the"transmitter zeroing method"is used to eliminate it.In terms of software design,the use of digital filtering technology,power-down protection technology,and software instruction redundancy measures can effectively improve the reliability of input microprocessor numbers.

 

　　以上是我们总结的几个去除漂移的方法，如果您在污水流量计使用时有更好的方法，也请联系我们与我们共同分享，我们非常感激您的合作态度。

 

　　The above are a few methods we have summarized to remove drift.If you have a better method when using sewage flow meters,please contact us and share with us.We are very grateful for your cooperative attitude.

       华恒资讯：威力巴流量计应用领域，看看用过的人怎么说？