Exact analytical prediction of magnetic field in a hybrid and wound excitation synchronous machine

This paper presents an analytical method for computation of magnetic field distribution and electromagnetic performances in salient pole synchronous generators. A 2D exact analytical solution of magnetic field distribution is established. It involves solution of Laplace's and Poisson's equations in stator slots, airgap and rotor excitation slots. Obtained exact analytical results of open circuit, armature reaction, on load magnetic field distribution, flux linkage, back-emf and self inductance are verified with those issued from finite element method (FEM). Assist effects by additional permanent magnets in salient-pole synchronous generators are also investigated analytically, even if these effects are present only for deep saturated machines.