Analytical prediction of armature reaction field distribution in PMAC machines with different winding configuration

An improved approach for predicting the armature reaction field in Permanent-Magnet AC (PMAC) machines is presented, and eddy current reaction is take into account. Winding configuration of PM machines could be various, such as concentric winding or lap winding, integral or fractional slot winding, distributed or concentrated winding, single-layer or double-layer winding. Starting with the field produced by coil, a mathematical relation is formulated between the winding field and the coil field by solving Maxwell's equations in each subdomain and applying boundary and continuity conditions. Significantly, each single coil is dealt with the pre-arranged algebraization and categorisation. As a result, an accurate solution of both radial and tangential components of the flux density can be obtained. Good agreement between predictions and finite element method (FEM) is achieved.