A study of end turn inductance calculation of BLDC motors
This paper presents the different calculating methods of stator end turn leakage inductance at brushless dc motors (BLDC) with different winding types. The calculations are carried both analytically and numerically. The results of the two dimensional (2D) calculations have been compared with the results of three dimensional (3D) ones for the same motor. Finite Element Method (FEM) is used for 2D and 3D numerical analysis.
Simulation of electrical machines end effects with reduced length 3D FEM models
This paper presents a fast simplified FEM calculation of electrical machines, which includes end effects. The considered machine size and power is similar to a 2.5 MW permanent magnet direct drive wind generator, and was simulated as a linear machine. The calculation uses a 3D model with a reduced length of the iron stack, and the full result is generated from the reduced length model and a 2D model of the cross-section of the inside region of the machine. The length of the reduced length 3D model, that is necessary for obtaining relevant calculation results, is analyzed here for different air gap sizes. A simple rule of the thumb for the necessary minimum axial length of the reduced length model can be derived from the presented numerical calculation results.
Polynomial modelling of electromechanical devices: an efficient alternative to look-up tables
A technique is described for taking results from complex numerical modelling procedures (such as a finite element model, a dynamic simulation or from experimental data) to create a simple yet accurate mathematical description of a device based on a modest amount of input data. The analytic model is then available for use within design or control programs that need to evaluate many examples quickly. The technique may be applied to a wide range of devices or systems. Examples are given for three applications.