FPGA Implementation of a Complex Permeability Measurement Instrument

As an irreplaceable part of industrial process, catalysts characteristics in the reaction process are getting more and more research. However, the traditional detection methods are off-line measurements, and the state of the catalysts cannot be known in real time, which does not do much effect on guiding the chemical reactions and production. Industrial Process Tomography (PT) is a method for online monitoring of multi-phase flow, in which Electromagnetic Tomography (EMT) has good imaging performances for particles with certain permeability or conductivity. Prior to EMT measurements, the electromagnetic properties of particles have to be acquired. In the previous research, a method for measuring the equivalent permeability of particle mixtures was proposed, in which the measurement system consisted of a four-tap solenoid coil sensor and a LCR meter. Based on our previous research, a portable measurement equipment has been designed to replace the LCR meter. This kind of instruments can work in different frequency conveniently and its SNR ranges from 56.3 dB to 78.5 dB. Experimental results in frequencies 31.25 kHz and 500 Hz show that the relative errors of the developed system arc below 8.14%.