1. (1) Y. Yamamoto, N. Kasa, H. Takami, T. Tazawa, S. Hattori, and S. Morimoto: “Trend of Applications of PM motors and New Technologies toward their Spread—Drive Control”, IEE Japan Industry Applications Society Conference, S9-6 (2009) (in Japanese)
2. (2) S. Shinnaka and H. Kubota: “Current situation and future issues at low-speed sensorless control of adjustable-speed AC Drive”, IEE Japan Industry Applications Society Conference, S3-3 (2013) (in Japanese)
3. (3) T. Takeshita, M. Ichikawa, J. Lee, and N. Matsui: “Back EMF Estimation-Based Sensorless Sailient-Pole Brushless DC Motor Drives”, IEEJ Trans. IA, Vol. 117, No. 1, pp. 98-104 (1997) (in Japanese)
4. (4) S. Morimoto, K. Kawamoto, and Y. Takeda: “Position and Speed Sensorless Control for IPMSM Based on Estimation of Position Error”, IEEJ Trans. IA, Vol. 122, No. 7, pp. 722-729 (2002) (in Japanese)
5. (5) S. Ichikawa, Z. Chen, M. Tomita, S. Doki, and S. Okuma: “Sensorless Comtrols of Salient-Pole Permanent Magnet Synchronous Motors Using Extended Electromotive Force Models”, IEEJ Trans. IA, Vol. 123, No. 12, pp. 1088-1096 (2002) (in Japanese)