Study Of Multi-Variable Vortex Transducer Based On Hart Protocol

Vortex transducer is a new type flowmeter that has developed from 1970's. Because of excelling others in some aspects, it has a wide applied range and expansive developing in the market. Multi-variable vortex transducer was developed on the basis of conventional votex transducer. It integrated temperature and pressure sensor with vortex sensor, and it realized the accurate measurement of mass flow through the compensation of gas density. The HART protocol is introduced in designs, and the function of remote communication is realized.The composition principle and mechanical structure of multi-variable vortex transducer is briefly described at first, and the formulas of density compensation which fit for different gases are presented on the basis of latest theory of gas density compensation. Then, the hardware and software designs of transducer that include the selection of chips, the design of the temperature and pressure signal collection circuit, the design of the vortex signal amplifier, the desigh of D/A convertion circuit and the design of some program processes are introduced in details. Furthermore, some methods of anti-interference and low power consumption are presented. Next, study is focused on the HART protocol content and how to communicate according to this protocol. At last, the whole system is tested and the satisfying results are achieved.Through the theory analysis and experiment check, this transducer can accomplish the target. It has exact result, simple measured circuits,...