Temperature stable MnZn ferrites for applications in the frequency region of 500 kHz

The temperature stability is a key design parameter in reaching the highest efficiency of modem medium frequency ferrite applications, such as in automotive, lighting, photovoltaic systems etc. These applications impose stronger demands on the performance of magnetic cores, such as low losses over a broad temperature range. In the present work the development of a MnZn ferrite polycrystalline material is described. The addition of the appropriate dopants, as well as the adjustment of the main composition resulted to a MnZn ferrite having initial magnetic permeability (mu(i)) of 1780 (measured at a frequency 10 kHz, an induction level 0.1 mT and a temperature 25 degrees C) and power losses (P-v) of 645.mW cm(-3) at 25 degrees C and 618 mW cm(-3) at 80 degrees C (measured at a frequency of 500 kHz and a magnetic field strength of 100 mT), establishing it as ideal for applications where low losses with small dependency on working temperature are needed. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.