Solid Rotor Induction Machines for use in Electrically-Assisted Turbochargers

The stator leakage reactance has a major influence on the performance of a solid rotor induction machine. It is larger and it is more difficult to define and calculate than in a cagerotor machine. When the higher leakage reactance is taken into account, the equivalent circuit model gives predictions of sufficient precision for design purposes. The airgap, normally chosen to be quite small, is preferably quite large by general standards. The torque varies as (V/f)3 which makes it difficult to provide a wide range of constant power operation in a variable speed application. Slitting the rotor helps to improve the characteristic for variable-speed duties.