We Claim:
[Claim 1] A control device for a rotary electrical machine, comprising:
a rotary electrical machine including an armature and a rotor; and
a controller configured to drive and control the rotary electricalal machine;
wherein the armature includes an armature core including: a plurality of magnetic teeth; and an armature winding formed of a multi-phase winding group, which is wound around the teeth 7, and is received in a slot between the teeth,
wherein the rotor includes a rotor core having a permanent magnet embedded therein, is arranged through magnetic air gap defined between the rotor and the armature, and is provided so to be rotatable about a rotation axis, and
wherein, below a number of revolutions at which field-weakening current for canceling counter-electromotive force is increased, the controller is configured to drive and control the rotary electrical machine at a current phase angle 9, which is different from a current phase angle 91 at which torque is maximized in constant energization current.
[Claim 2] The control device for a rotary electrical machine according to claim 1,
wherein, in a rated time in which energizing current is

maximum, the controller is configured to drive and control the rotary electrical machine at the current phase angle 91, and
wherein, in times other than the rated time, the controller is configured to drive and control the rotary electrical machine at a current phase angle 9 which is different from the current phase angle 9.
[Claim 3] The control device for a rotary electrical machine according to claim 2,
wherein, in times other than the rated time, the controller is configured to select the current phase angle 9 as a current phase angle at which torque larger than torque when the current phase angle is zero is allowed to output, and to drive and control the rotary electrical machine.
[Claim 4] The control device for a rotary electrical machine according to claim 2 or 3,
wherein, in times other than the rated time, the controller is configured to select the current phase angle 9 so that the following relationship: 9>91
is satisfied when the rotary electrical machine is driven and controlled.
[Claim 5] A rotary electrical machine to be driven and controlled

by the controller of the control device for a rotary electrical machine according to any one of claims 1 to 4,
wherein each of the armature and the rotor has such a configuration that, in the rated time, a current phase angle at which torque is maximized and a current phase angle at which torque ripple is minimized conform to each other.
[Claim 6] The rotary electrical machine according to claim 5,
wherein the electric rotating machine is a multi-layer
multi-phase winding permanent magnet motor,
wherein the rotor core has a step-skew structure with two or
more stages, and
wherein permanent magnets having different polarities in
different stages are arranged so as to be prevented from being
overlapped to each other when viewed along a rotation shaft
direction.
[Claim 7] The rotary electrical machine according to claim 5 or 6,
wherein the armature has a first armature winding and a second armature winding as the multi-phase winding groups, and
wherein an energizing phase of the second armature winding is configured to be shifted by 30 degrees from an energizing phase of the first armature winding.

[Claim 8] The rotary electrical machine according to any one of claims 5 to 7,
wherein an outer shape of the rotor core is formed as a flower round shape partially having a radius smaller than a radius of the true circle from the rotation center.
[Claim 9] The rotary electrical machine according to any one of claims 5 to 8,
wherein the multi-phase winding group is formed in distributed winding.
[Claim 10] The rotary electrical machine according to any one of claims 5 to 8,
wherein the multi-phase winding group is formed in concentrated winding.
[Claim 11] A method of controlling a rotary electrical machine to be driven and controlled by the controller of the control device for the rotary electrical machine according to any one of claims 1 to 4,
wherein, below a number of revolutions at which field-weakening current for canceling counter-electromotive force is increased, the controller is configured to drive and control the rotary electrical machine at a current phase angle 9, which is different from a current phase angle 91 at which torque is

maximized in constant energization current.