Abstract: In working mode some unexpected changes could
be arise in inner structure of electromagnetic device. They
influence modification in electromagnetic field propagation map.
The field values at an observed boundary are also changed. The
development of the process has to be watched because the arising
structural changes would provoke the device to be gone out later.
The probabilistic assessment of the state is possible to be made.
The numerical assessment points if the resulting changes have
only accidental character or they are due to the essential inner
structural disturbances.
The presented application example is referring to the 200MW
turbine-generator. A part of the stator core end teeth zone is
simulated broken. Quasi three-dimensional electromagnetic and
temperature field are solved applying FEM. The stator core state
diagnosis is proposed to be solved as an identification problem on
the basis of a statistical criterion.