Research On Control System Of Working Fluid Level's Optimization Of Oil Well In Intelligent Oilfields

At present, China's oil industry technology development has basically realized the mining process of digitalization, informatization and Internet, but some problems still exist. When long-term mining leads to the decrease of the working fluid level, domestic measures is to send workers to the scene by adjusting the parameters of the drilling operation. This is a low efficiency and high cost way. Therefore, this article designs a kind of control system of oil well working fluid level's optimization, the control system can real-time monitor the well's dynamic information, and realize rapid and accurate parameters adjustment.This paper studies a method based on indicator diagram measurement on the surface of the working fluid. Firstly, filter the collected data, and calculate the load of up and down stroke by using turning point of the convex hull graph. Secondly, calculate the sinking pressure, and compare it with the pressure calculated by annulus pressure gradient to get the working liquid level. Finally, correct the formula of working fluid level.To the control of working liquid level, this paper designs a control system of adaptive membership function, and describes the composition of control system, the design of the controller and the algorithms of membership function adapting in detail. Firstly, design the fuzzy controller by using the triangle membership function of input fuzzy sets. Then introduce the algorithm of membership function adapting. The algorithm includes four steps. Step 1: identify the controller output correction; step 2:confirm membership functions fixed direction according to the output correction; step 3:confirm the size of the membership function correction according to output correction; step 4:combine with the correction direction and correction size of membership function to modification.At the end of the paper, design a simulation. Compared with the common fuzzy control system and the adaptive membership function control system, it is concluded that the latter' control effect is better than the former's. At the same time, design the working liquid level monitoring software using c#, including the working fluid level calculation program, working liquid level control, indicator diagram show, working liquid level's curve display, parameters show of control process, and test the software function at the oilfield.