Control device for rotating electric machine

1. A control device for a rotating electric machine arranged in a rotating electric machine system, the rotating electric machine system comprising an electric power conversion unit and the rotating electric machine, the rotating electric machine comprising a stator on which phase windings are wound, the electric power conversion unit supplying a drive current to the phase windings of the stator to drive the rotating electric machine, the control device comprising:

a harmonic current calculation section capable of calculating harmonic currents to be superimposed over a fundamental current to be supplied to the phase windings of the stator so as to suppress electromagnetic force components affecting the rotating electric machine;

an operation section capable of operating the electric power conversion unit so that the drive current including the calculated harmonic currents which have been superimposed over the fundamental current flows in the phase windings of the stator,

wherein the harmonic current calculation section calculates the amplitude and phase of the harmonic currents to be superimposed over the fundamental current on the basis of conditions corresponding to a load of the rotating electric machine; and

a judgment section capable of judging conditions of instruction values generated by and transmitted from another control device, wherein

the conditions of the instruction values affect the load of the rotating electric machine,

the harmonic current calculation section calculates the amplitude and phase of the harmonic currents to be superimposed over the fundamental current on the basis of the correlation relationship between the amplitude and phase of the harmonic currents, and the conditions of the fundamental current judged by the judgment section, where the correlation relationship has been determined in advance,

the rotating electric machine forms a fan unit, and the control device uses an air flow mode as the conditions of the instruction values,

the control device uses a set temperature as the conditions of the instruction values,

the judgment section judges an instruction value of a rotation angular velocity of the rotating electric machine generated by and transmitted from the another control device,

the judgment section judges an air flow passage through which the blowing air is supplied from the fan unit on the basis of the air flow mode and the set temperature as the instruction values, and

the control device uses, as the correlation relationships between the conditions of the instruction values and the amplitude and phase of the harmonic currents, a relationship between the air flow passage, the rotation angular velocity of the rotating electric machine and the amplitude of the harmonic currents, and a relationship between the air flow passage, the rotation angular velocity of the rotating electric machine, and the phase of the harmonic currents.

2. The control device according to claim 1 , further comprising:

an acquiring section capable of detecting the fundamental current flowing in the phase windings of the stator,

wherein the conditions corresponding to the load of the rotating electric machine are conditions of the fundamental current flowing in the phase windings of the stator, and

the harmonic current calculation section calculates the amplitude and phase of the harmonic currents to be superimposed over the fundamental current which flows in the phase windings of the stator on the basis of the correlation relationship between the conditions of the fundamental current and the amplitude and phase of the harmonic currents, and the conditions of the fundamental current detected by the acquiring section, where the correlation relationship has been determined in advance.

3. The control device according to claim 1 , further comprising:

an acquiring section capable of detecting the fundamental current flowing in the phase windings of the stator; and

a judgment section capable of judging the conditions of instruction values generated by and transmitted from another control device,

wherein the conditions of the fundamental current flowing in the phase windings of the stator and the conditions of the instruction values affect the load of the rotating electric machine,

a first correlation relationship between the conditions of the fundamental current and the amplitude and phase of the harmonic currents, a second correlation relationship between the conditions of the instruction values and the amplitude and phase of the harmonic currents have been determined in advance, and

the harmonic current calculation section calculates the amplitude and phase of the harmonic currents to be superimposed over the fundamental current on the basis of the first correlation relationship and the conditions of the fundamental current acquired by the acquiring section, or the second correlation relationship and the conditions of the instruction values judged by the judgment section.

4. The control device according to claim 1 , wherein the control device uses the amplitude of the fundamental current as the conditions of the fundamental current.

5. The control device according to claim 4 , wherein the harmonic current calculation section increases the amplitude of the harmonic currents to be superimposed over the fundamental current according to increase of the amplitude of the fundamental current detected by the acquiring section.

6. A control device for a rotating electric machine arranged in a rotating electric machine system, the rotating electric machine system comprising an electric power conversion unit and the rotating electric machine, the rotating electric machine comprising a stator on which phase windings are wound, the electric power conversion unit supplying a drive current to the phase windings of the stator to drive the rotating electric machine, the control device comprising:

a harmonic current calculation section capable of calculating harmonic currents to be superimposed over a fundamental current to be supplied to the phase windings of the stator so as to suppress electromagnetic force components affecting the rotating electric machine;

an operation section capable of operating the electric power conversion unit so that the drive current including the calculated harmonic currents which have been superimposed over the fundamental current flows in the phase windings of the stator,

wherein the harmonic current calculation section calculates the amplitude and phase of the harmonic currents to be superimposed over the fundamental current on the basis of conditions corresponding to a load of the rotating electric machine; and

an acquiring section capable of detecting the fundamental current flowing in the phase windings of the stator,

wherein the conditions corresponding to the load of the rotating electric machine are conditions of the fundamental current flowing in the phase windings of the stator,

wherein the harmonic current calculation section calculates the amplitude and phase of the harmonic currents to be superimposed over the fundamental current which flows in the phase windings of the stator on the basis of the correlation relationship between the conditions of the fundamental current and the amplitude and phase of the harmonic currents, and the conditions of the fundamental current detected by the acquiring section, where the correlation relationship has been determined in advance,

wherein a K-th angular velocity is K times (K is an integer not less than two) of a variable angular velocity of the fundamental current flowing in the phase windings of the stator, a K-th harmonic current has a K-th angular velocity as a variable angular velocity, a K-th electromagnetic force component has a K-th angular velocity and affects the rotating electric machine, and

wherein when the suppression range of the electromagnetic force is from L-th (L is an even number not less than two) to (N−2)-th (N is an even number not less than two) which is larger than L-th, or from L-th to (N+2)-th which is smaller than L-th, the harmonic current calculation section calculates a plurality of even numbered harmonic currents within an order range from L-th to N-th.

7. The control device according to claim 6 , wherein at least one of the harmonic currents to be superimposed over the fundamental current are main harmonic currents, and

wherein the control device further comprises:

a memory unit capable of storing a main approximation equation or a map and sub-approximation equations, wherein

the main approximation equation or the map represents a correlation relationship of the harmonic currents,

the sub-approximation equations represent a relationship between amplitude and phase of the harmonic currents other than the main harmonic currents to be superimposed over the fundamental current which flows in the phase windings of the stator, and the amplitude and phase of the main harmonic currents, and

the harmonic current calculation section calculates the amplitude and phase of the harmonic currents to be superimposed over the fundamental current on the basis of the main approximation equation or the map, and the sub-approximation equations.

8. The control device according to claim 6 , further comprising:

a memory unit capable of storing approximation equations, each representing a correlation relationship of each of the harmonic currents to be superimposed over the fundamental current, wherein

the harmonic current calculation section calculates the amplitude and phase of the harmonic currents to be superimposed over the fundamental current on the basis of the approximation equation stored in the memory unit.

9. The control device according to claim 6 , wherein when the suppression range contains the (6M−2)-th electromagnetic force component and the 6M-th electromagnetic force component, the harmonic current calculation section calculates the (6M−1)-th harmonic current and the (6M+1)-th harmonic current.

10. The control device according to claim 6 , wherein when the suppression range contains the 6M-th electromagnetic force component and the (6M+2)-th electromagnetic force component, the harmonic current calculation section calculates the (6M−1)-th harmonic current and the (6M+1)-th harmonic current.

11. The control device according to claim 7 , wherein when the suppression range contains the (6M−2)-th electromagnetic force component and the 6M-th electromagnetic force component,

the memory unit stores the main approximation equation or the map representing the correlation relationship of one of the (6M−1)-th harmonic current and the (6M+1)-th harmonic current, and the sub approximation equations representing the relationship between the amplitude and phase of the (6M−1)-th harmonic current and the amplitude and phase of the (6M+1)-th harmonic current, and

the harmonic current calculation section calculates the (6M−1)-th harmonic current and the (6M+1)-th harmonic current to be superimposed over the fundamental current flowing in the phase windings of the stator on the basis of the main approximation equation or the map, and the sub-approximation equations.

12. The control device according to claim 7 , wherein when the suppression range contains the 6M-th electromagnetic force component and the (6M+2)-th electromagnetic force component,

the memory unit stores the main approximation equation or the map representing the correlation relationship between representing one of the (6M−1)-th harmonic current and the (6M+1)-th harmonic current, and the sub approximation equations representing the relationship between the amplitude and phase of the (6M−1)-th harmonic current and the amplitude and phase of the (6M+1)-th harmonic current, and

the harmonic current calculation section calculates the (6M−1)-th harmonic current and the (6M+1)-th harmonic current to be superimposed over the fundamental current flowing in the phase windings of the stator on the basis of the main approximation equation or the map, and the sub-approximation equations.