Compressor dynamic anti-surge control method based on variable working condition running

Abstract

The invention provides a compressor dynamic anti-surge control method based on variable working condition running. The method comprises the steps that S1, points are uniformly acquired on a surge limit line SLL in performance curves of a compressor, and a simplified polytropic head hr is calculated according to the type of vertical coordinates of the performance curves; S2, a simplified flow square qr<2> is calculated; S3, a dimensionless coordinate system (qr<2>, hr) is established by using the simplified flow square qr<2> as the horizontal coordinate and using the simplified polytropic headhr as the vertical coordinate; and S4, compressor running spaces and SLLs of the centrifugal compressor under different inlet running working conditions are subjected to normalization treatment in thedimensionless coordinate system, so that the only one SLL is formed, specifically, the mechanical structure and an internal flow channel of the centrifugal compressor are constant. The compressor dynamic anti-surge control method based on variable working condition running can achieve accurate, efficient and safe centrifugal compressor dynamic anti-surge control and remarkably improve the automation rate of compressor unit control.

Description

technical field [0001] The disclosure relates to the application of dynamic anti-surge control of centrifugal compressors in process industries such as petrochemical, coal chemical, and natural gas chemical industries, and is especially suitable for centrifugal compressors where the molecular weight MW of the process gas changes greatly (ΔMW > 20%) Anti-surge control method. Background technique [0002] In the petrochemical, coal chemical, natural gas chemical and other process industries, the process production equipment needs to go through air purging, nitrogen replacement, low-pressure airtight, high-pressure airtight and other processes during the start-up stage. During these processes, the gas molecular weight will occur. Dramatic changes; during the normal production period, with the progress of the production cycle, the activity of the catalyst decreases due to factors such as coking, so that the molecular weight MW of the reaction gas will change greatly in the e...

AI Technical Summary

Problems solved by technology

Once surge occurs, the vibration and displacement of the centrifugal compressor will increase significantly, which may cause serious mechanical damage to the centrifugal compressor, such as bearing damage, blade fracture, seal fracture and other mechanical accidents

On the other hand, once a surge occurs, the process driven by the centrifugal compressor will undergo severe pressure oscillations, which will seriously damage the normal process operation

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