Research On Multi-objective Optimization Of Drilling Multi-parameter Of Measurement While Drilling

One of the petroleum drilling engineering's key technologies is the measurement while drilling technology,the development of this technology provides precondition for real-time drilling parameter optimization.The real-time drilling parameter optimization required to establish accurate drilling model,experiment is usually adopted to get the model coefficient,but this method is inefficient which can not meet the real-time requirement,and the model is usually used as the unit footage cost model.In the actual project,we need to consider many factors comprehensively,such as the bit life and the mechanical energy ratio,and can get the model coefficient quickly and correctly.Firstly,this paper is analysis the relationship of the drilling parameter and establish the multi-objective optimization of drilling multi-parameter with the aim at the rate of penetration,the bit life and the mechanical energy ratio,and the decision variable of weight on bit,rotating speed,specific water power.In this model the method of inversion is used to get the unknown coefficient,and model coefficient can be corrected with the lapse of time.Then according to the multi-objective optimization of drilling multi-parameter and the defect of particle swarm optimization algorithm,the improvement strategy is presented for the algorithm.Choosing the ZDT test function set to test the arithmetic and compare with the test results of NSGA2 arithmetic.It turns out that the improvement arithmetic operation time is short and the test obtains the evenly distributed Pareto front.Finally,according to real-time drilling data of a practical oil field,use inversion method to solve the unknown coefficient of the model in real-time.Discussing the improvement of the parameter choice of the particle swarm optimization algorithm,and get a true Pareto front by simulation experiment in MATLAB,optimization parameter which selected from the Pareto front is convenience for drilling workers to adapt drilling parameter.