Finite element eddy current computations in turbogenerator solid rotors and imperfect stators

Finite elements are used to predict eddy currents and their effects in a large turbogenerator. First examined are transient eddy currents in the solid steel rotor. Their diffusion time is compared with an analytic equation and with time constants of finite element field decrement simulations. Also examined are the eddy currents produced by interlaminar insulation defects in the laminated steel stator. The eddy currents computed for typical EL CID tests are shown to accurately correspond with simulated EL CID readings.