Novel closed loop system and output signal processing of digital Coriolis mass flowmeter

In the processing of designing Coriolis mass flow measurement system, the novel digital method for processing the signals and calculating the results was introduced. The high performance parallel analog to digital converter (A/D) was utilized to sample the whole signals of the sensor. The sample data were deeply analyzed and processed by the high performance floating point DSP (digital signal processor). The classical signal processing method was used to filter the sample data and calculate the phase difference of the two signals, and that the mass flow and density of the liquid were calculated. The system was controlled and the output results were displayed and transferred by the single chip processor and the FPGA (field programmable gate array). Furthermore, the novel digital closed loop was brought forward in the closed loop resonant circuit, the digital circuits and digital signal processing methods were used to realize the traditional AGC (auto gain control) in the closed loop circuit. The experimental results show that the offset and the precision of the system are improved.