A Magnetic Equivalent Circuit to Account for Gaps Between Clamping Plate Segments in Large Synchronous Machines

摘要

End region effects in large synchronous machines are often investigated using 3DFEA, which is computationally expensive. This paper proposes the use of a simple magnetic equivalent circuit to model the impact of gaps between clamping plate segments and clamping plate eddy currents on the tangential clamping plate flux distribution. The tangential clamping plate flux distribution in turn can be used in a more comprehensive clamping plate loss calculation approach. Therefore, the methods presented in this paper should not be seen as a stand-alone methodology but rather as one building block in a more comprehensive calculation approach. Comparisons to 3D FEA and measurements on a 1,5 MVA test generator demonstrate the ability of the presented approach to capture the underlying flux transport mechanisms. The methodology is also used to predict the impact of the number of clamping plate segments and the gap width between those segments on clamping plate losses.