KYOTO, Japan (Nov. 13, 2014) – Nidec Corporation has announced that the Nidec Research and Development Center has developed a motor-drive system based on a silicon carbide (SiC) inverter. The Nidec Research and Development Center has succeeded in making the world’s first concept model of a drive system using a magnet-less motor with a SiC-based inverter by applying the above drive technology to a switched-reluctance (SR) motor, which is free of permanent magnets but requires a special control.
The future drive system should be compact, lightweight and efficient. Low power consumption is the most important challenge, because power consumption by motor-driven equipment accounts for 57.3 percent of total power consumption in Japan.*
Power semiconductors such as SiC and Gallium Nitride (GaN) have been developed, and the Nidec Research and Development Center has applied these to a compact and lightweight motor drive system, focusing on SiC semiconductors, which offer reduced power losses, improved heat resistance and higher current capacity. The volume and weight of the above concept model are 32 and 69 percent of the conventional motor drive system, including motor and inverter, respectively.
Design of the motor drive system required electrical circuit technology and thermal analysis technology to facilitate thermal management of the inverter circuit components.
Kyoto University has conducted decades of research and development of SiC power semiconductor devices. The SiC power semiconductors that were used by the Nidec Research and Development Center were developed through Nidec’s participation in the Kyoto super-cluster program of the Japan Science and Technology Agency. Many other universities, corporations and public research organizations were involved in the development.
A core institution of the Kyoto super-cluster program is the Advanced Scientific Technology & Management Research Institute of Kyoto. Specifically, the Nidec Research and Development Center has made open innovation by joint collaboration with ROHM, located in Ukyo-ku, Kyoto city; Nichicon, located in Nakagyo-ku, Kyoto city; and Kyoto University, Osaka University and Ritsumeikan University. The Nidec Research and Development Center has also made joint research with Yokohama National University in the technology of thermal analysis for motor drive systems, including circuit simulation of the SiC based inverter.
The Nidec Research and Development Center of Nidec Corporation has already developed a motor-drive system using a SiC-based inverter. An integrated motor-drive system (in which the inverter is built inside the motor housing) will be developed in 2015.
*Source: “The investigation report on present and future trend of power consumption of electrical instruments” by Research & Development Association for Future Electron Devices issued on March 23, 2009.