Power dissipated in the core while being energized. While the core is energized, even if there is no load on the secondary, power is being dissipated. There are two main causes of core losses. Hysteresis loss is that which occurs when the core material is continually being magnetized, demagnetized and re-magnetized in the opposite polarity. The more often it happens, which directly relates to frequency, the greater the losses. The other main source is hysteresis loss. See hysteresis loss for a description..
The power loss or heat generated by a magnetic material subjected to an alternating magnetic field.
Power dissipated by a magnetic core due to hysteresis and eddy currents.
Sum of hysteresis and eddy current losses in a magnetic circuit due to alternating current.
Core loss (or iron loss) is a form of energy loss that occurs in electrical transformers and other inductors. The loss is due to a variety of mechanisms related to the fluctuating magnetic field, such as eddy currents and hysteresis. Most of the energy is released as heat, although some may appear as sound ("hum").