A new method of characteristic analysis for three-phase induction motors

Generally speaking, the characteristics of induction motors (IM) are analyzed by means of the equivalent circuit with d-q transformation. Although this method is simple, the magnetic flux distributions in the stator and rotor are defined as sinusoidal waves. Therefore, the equivalent circuits become relatively complex for the high-frequency components and transient states. For detailed analysis, the finite element method (FEM) is used. The FEM can take account of the influence of skewed rotor bars and slots, and of the skin coefficient. However, the calculation time is very long for high-frequency components and transient analysis. We therefore propose a new method of characteristic analysis for IM. The proposed method analyzes the magnetic flux simply based on the construction of the IM. It can analyze transient and steady states and high-frequency components regardless of the type of source. The influence of skewed rotor bars and slots can also be treated simply. This paper describes the method of analysis, presents the results of the proposed method and compares them with experimental results, and describes the d-q transition. (C) 2001 Scripta Technica.