초록 ▼

In an electrical rotating machine, two rotors are provided, each rotor has a plurality of permanent magnets along its peripheral direction thereof, arranged coaxially with the other rotor, and is driven by means of a compound current supplied to stator coils and a single stator has a plurality of st

In an electrical rotating machine, two rotors are provided, each rotor has a plurality of permanent magnets along its peripheral direction thereof, arranged coaxially with the other rotor, and is driven by means of a compound current supplied to stator coils and a single stator has a plurality of stator coils through which the compound current is caused to flow, one of the rotors exhibiting a forward saliency characteristic and the other rotor exhibits a reverse saliency characteristic.

대표청구항 ▼

1. An electrical rotating machine, comprising:at least two rotors, each of the rotors having a plurality of permanent magnets along its circumferential direction thereof and arranged coaxially with the other rotor and being driven by means of a compound current supplied to stator coils; anda single

1. An electrical rotating machine, comprising:at least two rotors, each of the rotors having a plurality of permanent magnets along its circumferential direction thereof and arranged coaxially with the other rotor and being driven by means of a compound current supplied to stator coils; anda single stator having a plurality of stator coils through which the compound current is caused to flow, one of the rotors exhibiting a forward saliency characteristic and the other rotor exhibiting a reverse saliency characteristic. 2. An electrical rotating machine as claimed in claim 1, wherein, in one of the rotors exhibiting the forward saliency characteristic, a plurality of convex and recess portions are formed on every portion of the forward saliency characteristic exhibiting rotor in the circumferential direction thereof and the permanent magnets are arranged on respective convex portions thereof. 3. An electrical rotating machine as claimed in claim 1, wherein an aerial gap is provided on portions of the forward saliency characteristic rotor between the plurality of permanent magnets. 4. An electrical rotating machine as claimed in claim 1, wherein the rotating machine is driven in such a manner that the q-axis current related to the one rotor having the forward saliency characteristic is driven over a range such that the q-axis current is saturated by q-axis inductance and q-axis inductance is lowered than d-axis inductance of the one rotor having the forward saliency characteristic. 5. An electrical rotating machine as claimed in claim 1, wherein the rotors comprise an inner rotor located at an inside of the stator and an outer rotor located at an outside of the stator, the inner rotor having the reverse saliency characteristic and the outer rotor having the forward saliency characteristic. 6. An electrical rotating machine as claimed in claim 1, wherein the rotors comprise an inner rotor located at an inside of the stator and an outer rotor located at an outside of the stator, the inner rotor having the forward saliency characteristic and the outer rotor having the reverse saliency characteristic. 7. An electrical rotating machine as claimed in claim 5, wherein the inner rotor is provided with a recess portion located in a q-axis direction and is provided with a convex portion on which each permanent magnet is buried located in a d-axis direction which is separated by 45° in a mechanical angle with respect to the d-axis direction for the inner rotor to exhibit the forward saliency characteristic. 8. An electrical rotating machine as claimed in claim 5, wherein the inner rotor is of a circular shape in cross section and is provided with a substantially triangular shaped space in cross section in a q-axis direction and each permanent magnet is buried into the inner rotor which is aside each of the triangular shaped space for the inner rotor to exhibit the forward saliency characteristic. 9. An electrical rotating machine as claimed in claim 4, wherein the forward saliency characteristic exhibiting rotor is designed to saturate a q-axis inductance L q when the following current condition is satisfied: a torque curve of the forward saliency characteristic exhibiting rotor with respect to a d-axis current has an intersecting point to a current curve representing a q-axis current with respect to the d-axis current and the intersecting point is within a magnetic flux ellipse of the stator expressed as: λ={square root over (λ d 2 +λ q 2 )}, wherein and λ d =φ d +L d i d and λ q =L q i q , λ d denotes a magnetic flux of the d-axis, λ q denotes a magnetic flux of the q-axis, φ d denotes a non-load magnetic flux of the forward saliency characteristic exhibiting rotor, L d denotes a d-axis inductance, L q denotes a q-axis inductance, i d denotes the d-axis current, and i q denotes the q-axis current. 10. An electrical rotating machine as claimed in claim 6, whe rein the outer rotor has recess portions between the plurality of permanent magnets buried into an interior of the outer rotor which are faced with each stator piece for the outer rotor to exhibit the saliency characteristic. 11. A method applicable to an electrical rotating machine, the electrical machine comprising: at least two rotors, each rotor having a plurality of permanent magnets along its circumferential direction thereof, arranged coaxially with the other rotor, and being driven by means of a compound current supplied to stator coils; anda single stator having a plurality of stator coils through which the compound current is caused to flow, the method comprising: exhibiting a forward saliency characteristic for one of the rotors; and exhibiting a reverse saliency characteristic for the other rotor. 12. A method applicable to an electrical rotating machine as claimed in claim 11, wherein, to make the one rotor exhibit the forward saliency characteristic, the method further comprises forming plurality of convex and recess portions on every portion in the circumferential direction of the forward saliency characteristic rotor and arranging the permanent magnets on respective convex portions of the rotor. 13. A method applicable to an electrical rotating machine as claimed in claim 11, wherein the method comprises providing an aerial gap portions for the forward saliency characteristic rotor between the plurality of permanent magnets. 14. A method applicable to an electrical rotating machine as claimed in claim 11, wherein the method comprises driving the rotating machine in such a manner that a q-axis current related to the one rotor having the forward saliency characteristic is driven over a range such that the q-axis current is saturated by a q-axis inductance and the q-axis inductance is lowered than d-axis inductance of the one rotor having the forward saliency characteristic. 15. A method applicable to an electrical rotating machine as claimed in claim 11, wherein the rotors comprise an inner rotor located at an inside of the stator and an outer rotor located at an outside of the stator and wherein the inner rotor exhibits the reverse saliency characteristic and the outer rotor exhibits the forward saliency characteristic. 16. A method applicable to an electrical rotating machine as claimed in claim 11, wherein the rotors comprise an inner rotor located at an inside of the stator and an outer rotor located at an outside of the stator and wherein the inner rotor exhibits the forward saliency characteristic and the outer rotor exhibits the reverse saliency characteristic.