Polyester melt viscosity control system and control method thereof

The invention designs a polyester melt viscosity control system, mainly including a vibration-typed viscosity meter, a signal input unit, a control unit, a signal output unit and an actuator; the actuator is arranged on a polyester pipe; the vibration-typed viscosity meter is connected with the signal of the signal input unit; the signal output unit is connected with the actuator signal; a pressure detector is arranged on the polyester pipe; and the pressure detector and the vibration-typed viscosity meter are connected with a viscosity revising unit by signal. The control method of the control system adopts the viscosity signal of the melt in the polyester pipe which is detected by the vibration-typed viscosity meter and the pressure signal which is detected by the pressure detector as the detection signals, corrects the viscosity signal which is detected by the vibration-typed viscosity meter by making use of the relationship between the pressure and the viscosity in the polyester pipe, and uses the revised