The Designs Of High Precision Coriolis Mass Flowmeter Based On DSP Technical

Coriolis mass flowmeter is a high precision mass-flow measuring meter. It can directly measure mass flow and can do many parameters measurement at one time, so that it is favored by many customers. Now it becomes one of the most rapidly development flowmeters and has the brilliant prospect. But its work principle of fluid vibration and the signal processing method of count currently are so sensitive to noises that the precision is influenced by noises.In this paper, The DFT is used to process signals from the sensors of Coriolis mass flowmeter, and calculate the frequency and phase difference .In order to achieve the integral period sampling and ensure the precision of digital signal processing, a new technique that can be easily realized and track the frequency with high precision is proposed. The high performance parallel A/D to sample the whole signal is utilized. The 32 bit ARM processor chip LCP2104 analyzes the signals and calculates the phase difference of the two signals, then calculates mass flux and the others parameters. The system is controlled and output result is displayed by microcontroller. The system structure of the hardware and the important design flow of the software are introduced in the paper.The results of experiments have proved that the technique and system in this paper solved the problem that the precision of its signal processing method is influenced by noise, and ensured the high precision measurement.