The transformer core is one of the main components of the transformer and is used to provide a magnetic circuit that guides the magnetic field into the windings of the transformer. It is usually made of ferritic alloys (such as crystalline silicon steel sheets or amorphous alloys).

Common transformer core materials include crystalline silicon steel sheets and amorphous alloys. Crystalline silicon steel sheets feature low hysteresis and low iron loss, making them suitable for low-frequency applications. Due to its amorphous structure, amorphous alloy has lower hysteresis loss and iron loss, and is suitable for high-frequency applications and occasions with higher energy-saving requirements.

The main function of the transformer core is to provide a low reluctance magnetic circuit so that the magnetic field can pass through the core as much as possible without being lost. This improves the efficiency of the transformer and energy conversion efficiency.


The design of the transformer core must consider the magnetic flux density, that is, the magnetic flux per unit area. Higher magnetic flux density can increase the power density of the transformer, but also increases hysteresis loss and iron loss. Therefore, there is a trade-off between flux density and losses in the design.

The transformer core usually adopts a laminated structure, that is, the sheets of the core are stacked together. Such a structure can reduce eddy current losses and hysteresis losses, and improve the continuity of the magnetic circuit.

In order to further reduce the loss of the core, some compensation measures are often taken. For example, AC magnetization techniques (such as light load magnetization and harmonic magnetization) are used to reduce hysteresis losses and iron losses.

Transformer core design and selection are critical to transformer performance and efficiency. Through reasonable material selection, structural design and compensation measures, hysteresis loss and iron loss can be reduced, the energy utilization rate of the transformer can be improved, and energy waste can be reduced.