Device and method for controlling temperature of ultralow-temperature frosting cold surface cooled by low-temperature refrigerator

The invention discloses an ultralow-temperature frosting cold surface temperature control device and method cooled by a low-temperature refrigerator. The ultralow-temperature frosting cold surface temperature control device comprises a frosting generation cavity, a frosting test piece arranged in the frosting generation cavity and a PID controller used for controlling the temperature of the frosting test piece. The upper surface of the frosting test piece is a frosting cold surface, the lower surface of the frosting test piece is connected with a cold head of a low-temperature refrigerator through a flexible copper braided cold conduction belt, and a plurality of electric heating rods are uniformly arranged in the frosting test piece; a temperature sensor is arranged at the position, close to the lower surface of the frosting cold face, of the frosting test piece, the temperature sensor is used for measuring the temperature of the frosting cold face and serves as an input variable of the PID controller, the P