Study Of Generalized Predictive Control In Coal Seam Gas Horizontal Wells Development

The abundant coalbed methane(CBM)resources are the prominent features of coal resources reserves in China.In order to make full use of coalbed methane resources,the Chinese government has intensified its research on CBM development technology in recent years.How to mine coalbed methane resources safely and efficiently when an arduous task especially at the international energy forms become increasingly tense and environmental awareness continues to increase.The control of drilling and reaming is the key technology in the process of coalbed methane mining,which directly affects the success of mining.Based on the research of CBM mining automation control system,this paper designs a process control system with PLC and Kingview.The system is developed by the structure of upper computer and lower computer.The main contents include the overall design of the control system,hardware design,software design and simulation experiments on the control strategy of the drilling reaming system.The drilling and reaming process is a complex industrial object,and it is difficult to obtain an accurate mathematical model,conventional control strategies are also difficult to achieve the desired control effect.In order to improve the control quality of the drilling reaming system,the generalized predictive control theory is selected to realize the control of the drilling reaming system.Based on the design of the CBM development automation control system,the mathematical model of the drilling reaming system is established.The dynamic response characteristics of the system are analyzed by MATLAB software.The generalized predictive control strategy is robust to the interference quantity.On the basis of general generalized predictive control,a single-valued generalized predictive control strategy was introduced to greatly reduce the amount of online calculation and improve the response speed of the system.The algorithm was applied to the drilling reaming system and simulated with generalized predictive control and model predictive control.In contrast,the simulation platform of the drilling reaming controlsystem was finally built.On the Based of Kingview software and PLC,the system of coal sea gas horizontal well and control system was designed.The simulation experiment of the control algorithm was carried out.The simulation results show that the single-valued generalized predictive control strategy can effectively suppress the influence of various disturbances on the control performance of the system,The control effect has been greatly improved with stronger robustness and faster response.