A Novel Coriolis Flow Meter Signal Processing Method Based on Quadrature Demodulation

doi:10.12068/j.issn.1005-3026.2025.20240047

Abstract

Abstract:

In order to maximize the measurement performance of Coriolis flowmeter in practical application， a quadrature demodulation algorithm based on correlation operation and Hilbert transform （CH-QD algorithm） is proposed. The proposed algorithm uses the same-frequency cosine frequency characteristic of autocorrelation and the phase-shift characteristic of Hilbert transform to generate the reference signals required by quadrature demodulation， which effectively solves the problem that the traditional quadrature demodulation algorithm needs to predict the signal frequency and is sensitive to the performance of the frequency detection algorithm， which improves the detection accuracy of the algorithm， and realizes the joint estimation of signal frequency and phase difference. Simulation results show that the proposed algorithm has high detection accuracy， noise resistance and dynamic tracking performance. Based on TMS320F28335DSP， the algorithm is implemented on Coriolis flowmeter transmitter， and the performance analysis and water flow calibration experiments are carried out. The calibration results show that the measurement error of the system is less than 0.1% and the repeatability is less than 0.05% in the range of range ratio of 20∶1.

Key words: Coriolis mass flowmeter, signal processing methods, quadrature demodulation method, Hilbert transform, DSP

CLC Number:

TP 391.8

Xi-rong BAO, Hong ZHANG, Shi ZHANG. A Novel Coriolis Flow Meter Signal Processing Method Based on Quadrature Demodulation[J]. Journal of Northeastern University(Natural Science), 2025, 46(5): 20-28.

Figures/Tables 12

Fig.1 CH-QD block diagram

Fig.2 Spectrum of demodulation signals before and after multiple filtering

Fig.3 MSE of frequency results at different signal-to-noise ratios

Fig.4 MSE of phase difference results under different signal-to-noise ratios

Fig.5 Relative error of the algorithm under different phase differences

Fig.6 MSE of algorithm under different phase difference

Fig.7 Signal parameters

Fig.8 Phase difference results under MRWM model

Table 1 MSE under MRWM model

算法	频率MSE	相位差MSE
CH-QD法	2.58	2.73 $×$ 10^-6
CBF法	7.43	6.39 $×$ 10^-6
QD法	—	4.28 $×$ 10^-5
HT法	68.67	4.53 $×$ 10^-4
DTFT法	—	8.80 $×$ 10^-6

Table 1 MSE under MRWM model

算法	频率MSE	相位差MSE
CH-QD法	2.58	2.73 $×$ 10^-6
CBF法	7.43	6.39 $×$ 10^-6
QD法	—	4.28 $×$ 10^-5
HT法	68.67	4.53 $×$ 10^-4
DTFT法	—	8.80 $×$ 10^-6

Table 2 Algorithm processing time

算法	运算时间
CH-QD法	22.509 425
CBF法	18.628 330
QD法	64.442 105
HT法	8.734 995
DTFT法	70.460 935

Fig.9 Water flow calibration device

Table 3 Calibration results of the system

瞬时流量/(kg·min^-1)	标准值/kg	测量值/kg	误差/%	平均误差/%	重复性/%
37.13	20.447	20.455 6	0.004 3	0.013 5	0.032 5
	20.480	20.483 6	0.016 6
	20.501	20.496 9	-0.020 4
18.51	20.207	20.206 5	-0.001 2	0.003 1	0.034 9
	20.427	20.434 7	0.039 9
	20.389	20.383 1	-0.029 5
9.30	20.030	20.026 2	-0.017 8	-0.003 4	0.013 9
	19.990	19.989 6	-0.002 3
	19.888	19.890 0	0.009 9
1.83	19.694	19.695 7	0.007 5	-0.035 4	0.044 3
	19.642	19.635 7	-0.032 9
	19.791	19.774 6	-0.080 9
37.41	20.462	20.468 0	0.028 4	0.002 3	0.024 4
	20.490	20.485 9	-0.020 0
	20.471	20.470 9	-0.001 6

References 16

[1]	Romano P. Coriolics mass flow rate meter having a substantially increased noise immunity： US Patent， No 4934196［P］. 1990-06-19.
[2]	Hou Q L， Xu K J. A DSP-based signal processing method and system for CMF［J］. Measurement，2013，46（7）：2184–2192.
[3]	刘陈慈，徐科军，黄雅. 尿素机中高频微弯型科氏质量流量计信号处理［J］. 计量学报，2022，43（6）：767-776.
	Liu Chen-ci， Xu Ke-jun， Huang Ya. Signal processing of high-frequency micro-bending Coriolis mass flowmeter in urea machine ［J］. Journal of Metrology，2022，43 （6）：767-776.
[4]	徐长利，李波，钟其水，等. 基于过零检测的相位差计算方法的改进［J］. 机电信息，2022（2）：35-38.
	Xu Chang-li， Li Bo， Zhong Qi-shui，et al. Improvement of phase difference calculation method based on zero-crossing detection ［J］. Electromechanical Information，2022（2）：35-38.
[5]	Liu Y J， Wang L Y， Luo Q，et al. A novel method of Coriolis flowmeter phase difference measurement based on improved correlation analysis method［J］. Flow Measurement and Instrumentation，2021， 80：1-11.
[6]	Shen T A， Huang S Y， Chen P，et al. A novel phase difference measurement method for Coriolis mass flowmeter based on correlation theory［J］. Energies，2022，15（3710）：1-11.
[7]	沈廷鳌，涂亚庆，李明，等. 数据延拓式相关的相位差测量方法及验证［J］. 仪器仪表学报，2014，35（6）：1331-1337.
	Shen Ting-ao， Tu Ya-qing， Li Ming，et al. Phase difference measurement method and verification of data continuation correlation ［J］. Journal of Instrument，2014，35（6）：1331-1337.
[8]	张伦，徐科军，徐浩然，等. 面向批量流测量的科氏质量流量计正交解调方法实现［J］. 计量学报，2020，41（7）：808-815.
	Zhang Lun， Xu Ke-jun， Xu Hao-ran，et al. Implementation of orthogonal demodulation method for Coriolis mass flowmeter for batch flow measurement ［J］. Journal of Metrology，2020，41（7）：808-815.
[9]	Li M， Henry M. Complex bandpass filtering for coriolis mass flow meter signal processing［C］// 42nd Annual Conference of the IEEE Industrial Electronics Society（IECON）. Florence，2016：4952-4957.
[10]	Chen P， Tu Y Q， Li M，et al. A real-to-complex conversion phase difference estimation method for Coriolis mass flowmeter signal［C］ // 2019 International Conference on Communications， Information System and Computer Engineering （CISCE）. Haikou，2019：280-284.
[11]	Semenov A， Fedosov I. Novel prony-based algorithm for estimating oscillation parameters of Coriolis flowmeter at two-phase flow［C］// XXIX International Scientific Symposium Metrology and Metrology Assurance （MMA）. Sozopol，2019：1-6.
[12]	Lei H. An improved phase difference detection method for a Coriolis flowmeter［J］. Measurement，2021，172：1-7.
[13]	Li M， Henry M. Signal processing methods for Coriolis mass flow metering in two-phase flow conditions［C］// IEEE International Conference on Industrial Technology（ICIT）. Taipei，2016：690-695.
[14]	Li C H， Sun L J. Improvement of signal processing in Coriolis mass flowmeters for gas-liquid two-phase flow［J］. Frontiers of Information Technology and Electronic Engineering，2021，22（2）：272-286.
[15]	Chen N， Xiao Y， Liu Z，et al. Research on Coriolis mass flowmeter signal processing and driving method［C］ // 6th International Conference on Computing Methodologies and Communication （ICCMC）. Erode，2022：589-592.
[16]	Tu Y Q， Yang H Y， Zhang H T，et al. CMF signal processing method based on feedback corrected ANF and Hilbert transformation［J］. Measurement Science Review，2014，14（1）：41-47.