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Net Journal 9

Bringing new competitiveness to Japan’s automobile industry with rare earth-free high-performance motors

Masatsugu Takemoto

Masatsugu Takemoto, Doctor of Engineering,
Associate Professor of the Graduate School of Information Science and Technology, Hokkaido University,
Division of Systems Science and Informatics, Research Group of System Synthesis, Electric Energy Conversion Laboratory


Completed master’s degree in electrical engineering from the Graduate School of Engineering, Tokyo University of Science, in 1999, and PhD in electrical engineering from the Graduate School of Engineering, Tokyo Institute of Technology, in 2005. After stints as assistant and lecturer at the Tokyo Institute of Technology and Musashi Institute of Technology (renamed Tokyo City University in 2009), he assumed his current position in 2008. To this day, he has been engaged in the research of power electronics. He is especially focused on the development of electromagnetic devices such as bearingless motors and high-output/highly-efficient permanent magnet synchronous motors for hybrid electric vehicles. Member of the Institute of Electrical Engineers of Japan (IEEJ), Japan Society of Applied Electromagnetics and Mechanics (JSAEM), and the Institute of Electrical and Electronics Engineers (IEEE).

Contributing to the automobile industry with development of motor technologies

――Associate Professor Takemoto, you have been researching motors for many years. What is your primary focus?

Takemoto: Electrical energy in society today is like air and water. We can’t live with it. What’s more, motors consume about 55 percent of the total electrical energy in Japan. Improving the performance of motors has therefore become one of the most important research themes for effectively utilizing electrical energy. Researchers have been studying various types of motors for a while now. I am especially engaged in the research of motors used to drive hybrid electric vehicles (HEVs).

Current motors for HEVs use neodymium magnets (Explanation 1), which are made of rare earth elements. But in recent years, countries have become dependent on China for more than 90 percent of the world’s rare earth production. This has led to issues like skyrocketing prices and export restrictions. It is important to develop rare earth-free motors, which are less expensive and in more stable supply, in order to spread hybrid cars and electric cars rapidly. So in 2008 I joined the “High-Performance Battery System for Next-generation Vehicles” project, established by New Energy and Industrial Technology Development Organization (NEDO), and tackled the development of ferrite magnet motors for HEVs (Explanation 2).

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