Constant tension control system

The utility model relates to the technical field of metallurgy, in particular to a constant tension control system. An electro-hydraulic servo system is widely applied in a high-requirement, high-precision and rapid-responding device, and can be used for position control, speed control and force control fields or other control fields. The constant tension control system comprises an amplifier, an electro-hydraulic servo valve, a hydraulic cylinder, a tension adjuster, a force sensor, a loading device, an oil source and a hydraulic lock, wherein the amplifier, the electro-hydraulic servo valve, the hydraulic cylinder, the tension adjuster and the loading device are connected in sequence; the force sensor is connected between the electric amplifier and the loading device; the oil source and the hydraulic lock are connected with the electro-hydraulic servo valve. The constant tension control system provided by the utility model has a good control effect and can be recovered in place.