Patent ID: 7561943

Claim:
A method of controlling a volumetric ratio of a first material to total materials in a mixing vessel, comprising: estimating the volumetric ratio of the first material to the total materials in the mixing vessel and an output flowrate of the first material from the mixing vessel using a volumetric ratio observer, which provides filtered, zero-lag estimates of the actual volumetric ratios of materials in the mixing vessel by mathematical modeling that includes a modeled volumetric flowrate disturbance component; dynamically recomputing a commanded input flowrate of the first material based on outputs of the volumetric ratio observer using a flow regulator; and adjusting an input valve of the first material based on the commanded input flowrate of the material using a flow modulator that transforms the commanded input flow rate and a commanded volumetric ratio of the first material to total materials into positions of the input valve, and so volumetrically control the input valve utilizing the estimated volumetric ratio.