Instant Pot electric pressure cooker internal structure
An Electric Pressure Cooker consists of a pressure cooking container (inner pot or cooking pot), the electric heating element, and temperature / pressure sensors. The heating process is controlled by the built-in micro-processor based on the readings of the pressure and temperature sensors. This whole process forms a “closed loop control system” in control engineering terms. The principle is similar to that of cruise control found in many cars these days. The user puts all the ingredients in the cooking pot and sets the pressure cooking duration for the type of food to be cooked, the electric pressure cooker does the rest.
Over time, the leading electric pressure cookers learned from the experience and created different cooking profiles, such as simmering, steaming, braising, slow cooking, warming, rice cooking and stewing by using different combinations of cooking temperature, pressure and time duration. This has led to a new generation of electric pressure cooker, the programmable multi-cooker.
Read about how the electric pressure cooker works here.