托福机经:电磁炉的原理是什么

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An induction cooker uses induction heating for cooking. The usually ferromagnetic or ferromagnetic coated utensil is placed on top an induction coil for the heating process to take place. This form of flameless cooking has an edge over conventional gas flame and electric cookers as it provides rapid heating and vastly improved thermal efficiency. An induction cooker is also cleaner because it does not produce residual environmental heat and fumes.

The cooker works by producing eddy currents within the pan. These eddy currents within the pan create heat from the resistance of the metal as a result of induction. This heats up the pan, but no heat is generated from the actual stove (cooktop).

Induction cookers range from customized flush countertop units to portable single units.

电磁炉主要原理是灶本身把工频电源变为高频交流 电（频率为20-30khz)，灶相当于变压器的初级，而锅相当于变压器次级。变压器初级通高频交流电时，次级亦即是锅由于是整块导体，而感应出强大的涡流，导致短路而产生强大的热量，而完成电磁炉的所有功能。