WELL BORE PRESSURE MODEL PREDICTION SYSTEM CONTROL METHOD

摘要

The present invention relates to the technical field of well bore pressure control. Disclosed is a well bore pressure model prediction system control method, comprising: detecting during construction the well bottom pressure, vertical casing pressure, injection flow rate and outlet flow rate, and determining the presence of overflow or leakage; if there is no overflow or leakage, then fine-adjusting the wellhead casing pressure according to the slight fluctuations of the well bottom pressure or the vertical casing pressure, ensuring that the well bottom pressure or the vertical casing pressure are at the set value; if there is overflow or leakage, then using a well bore multi-phase flow dynamic model to simulate and calculate the overflow or leakage position and the overflow or leakage starting time, predicting the variation over a future time period of the well bore pressure in the well drilling process, and utilizing an optimization algorithm to calculate the control parameter under the minimum actual well bottom pressure difference over the future period; and repeating the optimization process for the next time period after a first control parameter is selected and set. The present method enables the well bore pressure to be controlled within the allowable fluctuation range of a project, thus achieving precise pressure control.