How to reduce the loss of inductor cores?

Causes of loss of inductor cores:

The loss of the chip inductor core is mainly in the core loss and the coil loss, and the size of the loss in these two aspects needs to be judged according to its different circuit modes. Among them, the core loss is mainly caused by the alternating magnetic field in the core material, and the loss generated by it is a function of the operating frequency and the total magnetic flux swing (δb), which will greatly reduce the effective conduction loss. Coil loss is due to the energy loss caused by the change in magnetic energy, which reduces the strength of the magnetic field when the power inductor current drops.

Methods for reducing losses in inductor cores:

1. The allowable copper wire loss generated in the inductor core will decrease with the increase of the inductor core loss, and it will also bring about a surge in the flux of the same inductor core material. As a result, when the switching frequency rises above 500 kHz, the inductor core losses and winding AC losses can significantly reduce the allowable DC current in the inductor.

2. The loss in the inductor core ** ring is mainly manifested in the copper wire loss, so if you want to reduce the copper wire loss, you must reduce it when the inductor core loss rises, and continue until the losses are equal. The best-case scenario is that the losses are stable at high frequencies and allow the maximum output current to be obtained from the magnetic structure.

I believe we all know that inductor cores will be lost in the process of use, and the size of the loss is mainly judged according to its different circuit modes. So how do we calculate the loss of an inductor core? The following inductor core manufacturer Baili Bao will introduce to you:

As the switching frequency rises above 500 kHz, the inductor core losses and winding AC losses can greatly reduce the allowable DC current in the inductor. Using 20% ripple current to calculate the inductance results in the same surge in flux of inductor core material, independent of frequency. The general form of the core inductance loss equation is:

pcore = k ×

Therefore, if the frequency (f) is increased from 100 kHz to 500 kHz, the core loss is 8 times greater. It will decrease the allowable copper wire loss as the inductor core loss rises. At 100 kHz, most of the losses are present in the copper wire, while it is possible to utilize a full DC current rating.

At higher frequencies, the inductor core losses become larger.

In addition, since the total allowable loss is determined by the sum of the inductor core loss and the copper wire loss, the copper wire loss must be reduced as the inductor core loss rises. This continues until all the losses are equal. Best-case scenario, the losses are stably equal at high frequencies and allow the maximum output current to be obtained from the magnetic structure.

Details can be found here.