Knob assembly, control method thereof and household appliance

The invention relates to a knob assembly, a control method thereof and a household appliance. The knob assembly comprises a panel; the knob is magnetically adsorbed on one side of the panel and can rotate; the optical detection piece is arranged on one side, deviating from the knob, of the panel and is used for detecting the rotation angle of the knob; a flange is annularly arranged in the rotary knob in the circumferential direction of the rotary knob, and the flange is obliquely arranged in the axial direction of the rotary knob. The control method of the knob assembly comprises the following steps that under the condition that the knob is connected with the panel in a matched mode, the optical detection piece is controlled to be in a triggered state, the optical detection piece emits a measuring light beam into the knob, and the measuring light beam returns to the optical detection piece after being reflected by the flange; and obtaining the rotation angle of the knob according to the detection result of t