Patent ID: 9172324
Filing Date: 2015-10-27
Classification: H02K,H02P

Abstract:
1. A motor drive system, comprising: a motor having a plurality of coils classified into a group A and a group B, a stator having a plurality of teeth, around each of which any one of the coils classified into the group A and the group B is wound and which are arranged in an annular shape, a rotor shaft which is provided inside the stator and extends in the axial direction, and a rotor which is externally fitted to the rotor shaft; a first controller which applies three-phase voltages of a U phase, a V phase, and a W phase to each coil classified into the group A; a second controller which applies the three-phase voltages to each coil classified into the group B; and wherein a sensor portion outputs an electric signal according to a rotation angle of the rotor shaft to the first controller and the second controller; wherein a number X of magnetic poles of the teeth of the stator and a number Y of magnetic poles of magnets of the rotor satisfy Expression 1, X:Y=6n:6n±2, wherein, n is an integer of 2 or more; wherein a total number of the coils when the teeth of the stator are set as one unit is equal to the number X of magnetic poles of the teeth; wherein both a total number of the coils contained in the group A and a total number of the coils contained in the group B is X/2; wherein the first controller and the second controller apply the three-phase voltages to the corresponding coils, irrespective of whether the other controller applies the three-phase voltages to the coils; wherein an induced voltage of each coil in each of the group A and the group B constitutes the three phases and the phase of the induced voltage of each coil of the same phase in each of the groups is the same; wherein there is a phase difference between the induced voltage of each coil contained in the group A and the induced voltage of each coil contained in the group B; and wherein the sensor portion has a first sensor and a second sensor each having a resolver stator having a plurality of resolver teeth, around each of which an excitation winding, a first output winding, and a second output winding are wound and which are arranged in an annular shape and a resolver rotor which is provided inside the resolver stator and integrally rotates with the rotor shaft.