1. School of Electrical and Automation Engineering,Hefei University of Technology, Hefei, Anhui 230009, China
2. Engineering Technology Research Center of Industrial Automation, Hefei, Anhui 230009, China
Abstract:In order to improve the measurement accuracy of the Coriolis mass flowmeter under batch flow conditions,the quadrature demodulation algorithm is selected as the signal processing method according to the characteristics of rapid response,it solves the difficulties in the implementation process. the demodulation signal with single period finite point data is realized by using the periodic characteristics of the sinusoidal signal;besides the demodulated signals are filtered by cascading the FIR notch filter and the IIR low-pass filter while guarantee accuracy and reduce algorithmic computation;a secondary average is added in the post-processing in order to reduce the steady-state fluctuations and remove the singular points in the calculation results,in addition,the resource configuration during algorithm implementation is optimized. On this basis,the Coriolis mass flow transmitter was developed,and the single-phase flow and batch flow calibration experiments were carried out. The measurement error was less than 0.1% and the repeatability was less than 0.05%. The experimental results show that the quadrature demodulation algorithm has better measurement accuracy under the batch flow,and the developed transmitter has better performance.
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