The working principle of semiconductor refrigeration sheet is based on Peltier’s principle. This effect was first discovered by j.a.c. Peltier in 1834, that is, when the circuit composed of two different conductors A and B is connected with direct current, some other heat will be released at the joint in addition to Joule heat, while the other joint absorbs heat, Moreover, this phenomenon caused by Peltier effect is reversible. When changing the current direction, the exothermic and endothermic joints also change. The absorbed and released heat is directly proportional to the current intensity I [a], and is related to the properties of the two conductors and the temperature of the hot end.