The Application Research Of Propylene Fractionation Tower Based On Nerve Net Soft Measurement Technology

Soft measurement technology is also named soft instrument technology. It uses easy-to-measure process variable (It is also named assistant variable or secondary variable.), and bases on the relation (soft measurement model) between the easy-to-measure process variable and the need measuring process variable (It is also named main variable) which is difficult to measure directly to measure or estimate the need measuring process by all kinds of mathematic calculation and estimation methods. At present, the soft measurement technology has become one hotspot in the field of process control.In this thesis, it introduced the calculation methods of BP nerve net, RBF nerve net and blurry nerve net. Take the gas fractionation unit of one refinery as the background to find out a representative propylene fractionation tower which based on entirely digesting and absorbing the foretime study fruit, fully analyzing the system characteristic, and the details of production unit. Take the real time data of assistant variable obtained by top computer of DCS as the training sample, apply the BP nerve net and RBF blurry nerve net of manual nerve cell net soft measurement technology to the object propylene fractionation tower to conduct model identification, then compare the forecast value and the measurement to prove that the identified object model can well perform the dynamic action of the object and it has good popularization performance.