The iron core in a transformer does get hot during operation, but it doesn't reach the same temperature as a pan on an induction burner due to several factors:
Design and materials: The iron core in a transformer is typically made of laminated iron or steel, which has relatively high thermal conductivity. This allows for efficient heat dissipation, preventing localized hot spots from forming. The laminated structure also reduces eddy currents that can generate excess heat. Additionally, the transformer is designed to distribute the heat evenly across the core.
Induction mechanism: In an induction cooktop, the heat is generated by the resistance of the pan's material to the alternating magnetic field. The pan itself acts as a heating element. In contrast, the iron core in a transformer is not intended to generate heat. It serves the purpose of transferring magnetic flux and facilitating energy transfer between coils.
Operating conditions: Transformers are designed to operate within specific temperature limits. They are typically insulated and cooled to maintain their temperature within acceptable ranges. Cooling mechanisms such as fans, oil-filled enclosures, or external cooling systems help dissipate heat and maintain the core temperature at a safe level.
Power levels: Induction cooktops are designed to deliver high power levels to heat cookware quickly. They operate at higher frequencies, typically in the range of several kilohertz, which leads to more intense heating. In contrast, transformers operate at lower frequencies, often in the range of 50-60 Hz, and are not designed for high-power heating applications.
Overall, the differences in design, materials, intended function, and operating conditions contribute to the core of a transformer not reaching the same temperature as a pan on an induction burner. Transformers are engineered to efficiently transfer electrical energy while minimizing heat buildup, ensuring their safe and reliable operation.