Fast Finite-Element Analysis of Motors Using Block Model Order Reduction

This paper proposes a model order reduction (MOR) based on the proper orthogonal decomposition (POD) to perform a fast analysis of motors. When a POD-based MOR is applied to the motor analysis, the number of basis vectors has to be increased to express the changes in the magnetic fields due to a rotational movement. Its computational efficiency is, thus, greatly deteriorated. To overcome this difficulty, the block-MOR is first applied to a motor analysis. In this method, a parameter space is subdivided into several blocks, which correspond to angular ranges in the motor analysis, in each of which the basis vectors are constructed from snapshotted fields. The computational time of the block-MOR is shown to be shorter than that of the conventional MOR, while the accuracy of both the methods is almost identical.

I. Introduction

In the design of the control and driving systems of the motors, the equivalent circuits and the behavior models of the motors are widely used rather than finite-element (FE) models whose computational time is rather long for dynamic simulations [1]. The accuracy of the former two methods is, however, often unsatisfactory, especially for loss evaluation. For this reason, fast and accurate computational methods for the motor analysis have been required.