Research And Implementation Of Coordinated Control Strategy For Shield Machine Propulsion System

As an important engineering machine in the construction of urban subway, shield machine is mainly used for the construction of underground tunnels. During the construction of shield machine, not only to achieve straight forward, but also need to achieve other function such as turn, curve forward, rectification, posture adjustment, ect. Therefore, the precise control of the population system is of great siganificance in the research of shield machine technology.In this paper, the background of the shield machine control system is rebuilt , aiming at the control of the propulsion system mainly completes the following tasks.Firstly, the control principle of propulsion system is briefly introduced. The paper introduced two kinds of methods to control the amount of dumping sealed chamber and into the soil volume principle. And then to achieve the screw conveyor speed and propulsion speed of the coordinated control, the use of fuzzy PID control method to complete the seal of the seal pressure adjustment. And the establishment of the seal chamber of earth pressure balance model, the feasibi lity of these two methods is verified.Secondly, the hydraulic control principle of the propulsion system is described in detail.The object of the hydraulic cylinder was studied. In AMESim, the simulation model of open-loop and closed-loop control of hydraulic propulsion cylinder is established. The open-loop and closed-loop simulation experiments of thrust pressure and propulsion speed are carried out, which lays the foundation for compiling PLC control program of propulsion system. The simulation results show that the double closed loop control of pressure and velocity, can effectively reduce the mutual influence between the two, so as to improve the control effect of the propulsion system.Thirdly, the design of propulsion control system based on programmable logic controller(PLC) is completed. The design of the propulsion system of electric control system,completed the PLC hardware configuration and program implementation, promote system PLC program functions needed in shield tunneling segment and the two work mode, to achieve control of the propulsion system, and completed based on PLC program debugging,to achieve the desired effect.Finally, to control the foam unit in the system of shield machine advancing, using embedded LPC1788 as the control unit, the hardware circuit design of the complete C/OS foam system, complete with real-time operating system transplant, low-level driver and man-machine interface design, based on the hardware platform, finally, parameters of foam in the system of monitoring, acquisition and control functions.