The structure and working principle of the semiconductor type car refrigerator

The basic structure of the semiconductor car refrigerator is:

Connect the P-type semiconductor, N-type semiconductor, copper plate and copper wire into a loop. The copper plate and the wire only play a conductive role. The circuit is powered by 12V DC. After the current is turned on, one contact becomes cold (inside the refrigerator), and the other is cooled. (radiator behind the refrigerator). Semiconductor electronic refrigeration, also known as thermoelectric refrigeration, is a refrigeration method using the "Peltier effect".

In 1843, Peltier connected a bismuth wire to each end of the copper wire, and then connected the two bismuth wires to the positive and negative poles of the DC power supply. cooling, a phenomenon later known as the "Peltier effect". The principle is: the charge carrier moves in the conductor to form a current. Since the charge carrier is in different energy levels in different materials, when it moves from a high energy level to a low energy level, it will release excess heat; Absorbs heat from the outside world (i.e. acts as cooling).

According to the principle of "Peltier effect", it can be seen that when two different metals are energized at the junction point, according to the different polarities, the two metals will have cooling and heating effects respectively. Semiconductor refrigeration refrigerators take advantage of this to aggregate batches of metal junctions to increase the cooling and heating effect, and then use the cooling or heat source on the metal surface to flow with heat-dissipating aluminum sheets and fans, which can form a cooling and heating effect.

The semiconductor refrigeration chip is composed of many N-type and P-type semiconductor particles arranged with each other, and the N and P-type semiconductors are connected by ordinary conductors to form a complete circuit, usually copper, aluminum or other metal conductors, and finally composed of two. The ceramic sheet is sandwiched like a sandwich biscuit, and the ceramic sheet must be insulated and thermally conductive.

The temperature of the semiconductor refrigeration chip can reach minus 5°C under this condition, but after conduction, it is reflected to the refrigerator wall, and then transmitted from the refrigerator wall to the inside of the box, and the temperature decays to 5°C above zero, but it is only under ideal conditions. temperature. Another important index is that the temperature of the hot and cold box can only reach a temperature difference of about 20 ℃ with the temperature of the surrounding environment.