Finding end winding inductances of MVA machines

Correct FEM computations of end windings leakage inductances of MVA-range machines are discussed. This is shown through validations against total stator reactance measurements of 11 air-suspended stators and a reasonable agreement of FEM computations with the IEC 60034-4 standard. To achieve this goal the need to have several 2D- and 3D-FEM models including those representing the cooling ducts is emphasized. Steps to utilize the validated stator FEM models for direct computation of end windings leakage inductances are also listed. It is also shown that measurements of zero-sequence reactances can not help the FEM validations and do not provide a reliable estimation of leakage inductances.