Hitachi Metals, Ltd. is pleased to announce the successful development of block cores with both a high saturation magnetic flux density and low core loss at high frequencies using FINEMET^® nanocrystalline soft magnetic materials and Metglas^® amorphous metals. This product will minimize the size of transformers and reactors more than ever before.

1. Background

Power conditioners for renewable energy and auxiliary power supplies for railway vehicles employ coil products such as transformers and reactors for power conversion. Higher switching frequencies of semiconductors allow power converters to use smaller coil products, which can minimize the size of power converters.
However, the switching frequency and power capacity of conventional systems that use Si (silicon) semiconductors are limited by the withstand voltage and heat generation of semiconductors. Recently, the growing performance of IGBT^*1 using Si and the advent of next-generation semiconductors such as SiC (silicon carbide) and GaN (gallium nitride) have necessitated the use of a larger capacity and higher switching frequency more than ever before. High-frequency transformers and reactors using electrical steel sheets have a higher core loss^*2 in the high-frequency ranges, and suppression of the temperature rise caused by this loss makes it difficult to downsize the system.

• 
  Photo: F3BC—FINEMET^® block core

2. Outline

Making full use of the technical characteristics of FINEMET^® nanocrystalline soft magnetic materials and Metglas^® amorphous metals, Hitachi Metals has developed F3BC FINEMET^® block cores and AMBC amorphous block cores to fulfill the need for large cores of large-capacity transformers.

F3BC:

can be used for square-ring shaped large cores, contributing to smaller transformers capable of handling over 100 kW of power

AMBC:

can be easily employed for large multi-gap cores, contributing to reducing core loss caused by fringing flux^*3 and suppressing heat generation

FINEMET^® is suitable for transformer cores working at a high switching frequency—5 to 20 kHz in particular—whereas amorphous metals are suitable for reactor cores working with a high-frequency ripple^*4. Since FINEMET^® and amorphous metals have a significantly smaller core loss and higher switching frequency than electrical steel sheets, Hitachi Metals has provided UU-shaped cut cores made of FINEMET^® and amorphous metals. The new block cores will contribute to the development of smaller and lighter transformers operating in a high-frequency range with higher efficiency in power transformation. In addition, we will not only provide block cores with a standard shape for initial evaluation, but also manufacture cores with shapes based on customer requests.

 

We will continue our quest to design materials that draw out the properties of raw resources, contributing to electronic components with a higher performance, and will address an even more extensive range of customer needs.

3.Production Status

Sample shipment: January, 2017
Mass production: Second half of FY2017

4.Production Bases

Hitachi Ferrite Electronics, Ltd.
Hitachi Metals (India) Pvt. Ltd.
Hitachi Metals (Thailand) Ltd.

5.Patents

Basic patents have been obtained.

For inquiries from customers:
High-Grade Metals Company, Hitachi Metals, Ltd.
Click Here

For inquiries from the press:
Corporate Communications, Hitachi Metals, Ltd.
hmcc.sa@hitachi-metals.com

• Hitachi Metals Announces the Development of Block Cores of High-frequency Power Converters for Handling over 100 kW Using FINEMET^® Nanocrystalline Soft Magnetic Materials and Metglas^® Amorphous Metals(PDF：)