Development Of Digital Signal Processing System For Vortex Flowmeters With Low-power And Two-wires

Digital signal processing technology and low-power technology have been applied to Vortex flowmeters in recent years. Generally speaking the digital signal processing algorithm is implemented by DSPs to achieve the accurate calculation results and high measurement precision. However, the power consumption of meters with DSPs is very large, and cannot meet the requirements of both the low-power and two-wires. The existing low-power Vortex flowmeters adopt the common signal processing method, which is easy to be realized, but cannot ensure the measurement precision in fields.There are some contradictions between digital signal processing method and low-power technology. But some industry fields need the meters with low-power and two-wires. Therefore, an ultra-low-power MCU chip MSP430F1611 is used to develop a digital signal processing system of Vortex flowmeters with low-power and two-wires. The digital spectral analysis is combined with the analog band-pass filters to filter noises contained in vortex signal, improve the measurement accuracy and ensure the low power consumption in the system. A programmable gain amplifier is built using the low-power operational amplifier and potentiometer to adapt large amplitude variation of vortex signal. A special power supply module is designed to provide enough current for the meter with two-wires.