A permanent magnet rotor comprises a rotor body configured for rotating around a central rotational axis and further comprises principal permanent magnets that are substantially rectangular in axial cross-section and are embedded in the rotor body and are arranged inclined with respect to the radial plane extending through the center of the principal magnets and such as to have a circumferential magnetic orientation. The principal magnets have an inner end and an outer end, the outer end being arranged in the proximity of the air gap of the outer circumference of the rotor, and outer bridges of magnetically conductive material being formed between the outer ends of the principal magnets and the outer circumference of the rotor. Auxiliary magnets are arranged near the outer ends of the principal magnets to magnetically saturate the outer bridges.