J-TEXT,formerly TEXT-U at the University of Texas at Austin in USA,is a medium-sized tokamak at the Huazhong University of Science and Technology.The toroidal field (TF)power supply of this tokamak should provide a current of 160 kA and a fiat duration of 500 ms for the toroidal field coils to generate a maximum toroidal field of 3 T at the geometric center of the vaccum vessel.This paper presents a design of a new control system which takes the real-time feedback control option for the TF power supply operation.The system was tested successfully during the commissioning.In the first experimental campaign of J-TEXT,the system effectively controlled the power supply to provide a flat current up to 92.5 kA and therein the TF produced reached 1.74 T,which enabled the machine to generate the first plasma successfully. J-TEXT, formerly TEXT-U at the University of Texas at Austin in USA, is a medium-sized tokamak at the Huazhong University of Science and Technology. The toroidal field (TF) power supply of this tokamak should provide a current of 160 kA and a fiat duration of 500 ms for the toroidal field coils to generate a maximum toroidal field of 3 T at the geometric center of the vaccum vessel. This paper presents a design of a new control system which takes the real-time feedback control option for the TF power supply operation. The system was tested successfully during the commissioning. the first experimental campaign of J-TEXT, the system effectively controlled the power supply to provide a flat current up to 92.5 kA and therein the TF produced reached 1.74 T , which enabled the machine to generate the first plasma successfully.