Novel voltage limiter for fast torque response of IPMSM in voltage saturation region

• Published in: Electrical engineering in Japan Vol. 175; no. 4; pp. 57 - 69
• Main Authors: Lerdudomsak, Smith, Doki, Shinji, Okuma, Shigeru
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.06.2011
• Subjects: Electric potential; Hardware; IPMSM; Mathematical analysis; On-line systems; Online; Saturation; Torque; torque response; Voltage; voltage limiter; voltage saturation
• ISSN: 0424-7760; 1520-6416; 1520-6416
• DOI: 10.1002/eej.21078

A new voltage limiter for fast torque response of IPMSM in the voltage saturation region is proposed, which we name the “maximum torque response voltage limiter.” In transient condition, the fastest response is vital while voltage saturation occurs. Thus, the problem is to divide the limited voltage into d‐ and q‐axis voltages so as to generate the fastest torque response. The nonlinear relation between the torque and the d‐q axis currents of the IPMSM makes the problem complicated. In our proposed method, both voltage equations and a torque equation of the IPMSM are considered and, based on the Lagrange optimization technique, explicit expressions for the d‐ and q‐axis voltages are derived. Compared with conventional voltage limiters such as the constant phase angle method, the constant back emf method, and the constant d‐axis voltage method, the proposed limiter yields faster torque response in the voltage saturation region, which is confirmed by computer simulation and experimental results. Furthermore, the proposed method uses simple software calculations, and it can be readily implemented without any modification of the hardware system. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(4): 57–69, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21078