Fine dredging control method for trailing suction hopper dredger

The invention relates to a dredging control technology of a dredger, and discloses a fine dredging control method for a trailing suction hopper dredger. In the method, the ascending or descending amplitude parameter of a drag is input to a controller through a pulling and piling device, and the controller is used for converting a signal received from the pulling and piling device into a control signal for lifting or lowering the drag, wherein the controller is used for controlling the lifting or lowering duration of the drag; when the lifting or lowering duration of the drag ends, the controller is used for automatically disconnecting an output control signal. The working state of the controller is displayed via a working indicating lamp. In case of an emergency, construction personnel can transmit an emergency lifting control signal to a drag control mechanism through the controller. According to the control method, fine dredging of the drag can be realized, and fine dredging control of the trailing suction hopper dredger can be realized even when the control accuracy of a drag depth position surpasses the range of manual control capacity.