Copy cutting system of tunneling machine

The invention relates to a copy cutting system of a tunneling machine, which is applied to tunneling machine industry. The copy cutting system of a tunneling machine comprises a programmable logic controller, a cantilever displacement sensor, a spading plate displacement sensor, an electromagnetic valve box, an explosion-proof keyboard and a liquid crystal display screen. The copy cutting system needs to be completed by mutually matching an electric control system and a hydraulic system. The copy cutting system of the tunneling machine comprises double closed-loop control: displacement closed-loop control and constant power closed-loop control of a cutting motor, wherein in the displacement closed-loop control, after section parameters X, Y and R which are desirous to be realized are input by the explosion-proof keyboard in a cutting picture, the programmable logic controller is used for controlling an electromagnetic valve in the electromagnetic box of a corresponding oil passage to open, and specified values of the input section parameters form a closed loop with feedback signals collected by the cantilever displacement sensor and the spading plate displacement sensor. The copy cutting system can realize cutting automation. Because a front coal layer drops dust in an operating process of the tunneling machine, an operator can not see a specific condition of a working surface, the copy cutting system can be used for completing the cutting action and greatly increases the applicability, the reliability and the accuracy of the tunneling machine.