1. A reluctance motor system to be powered by a direct current (DC) power source and comprising:
a reluctance motor including a stator and a rotor, said stator including M phase winding sets, M being an integer not smaller than 3, each of said phase winding sets including a first winding and a second winding that are disposed at diametrically opposite positions of said stator, and that are connected in series at a corresponding node; and
a driving circuit including
M switching members each of which is coupled electrically to a respective one of said phase winding sets, and each of which includes a first switch coupled electrically to a first end of said respective phase winding set, a second switch coupled electrically to a second end of said respective phase winding set opposite to the first end thereof, a first flyback diode with a cathode coupled electrically to the first end of said respective phase winding set and with an anode to be coupled electrically to a negative terminal of the DC power source, and a second flyback diode with a cathode to be coupled electrically to a positive terminal of the DC power source and with an anode coupled electrically to the second end of said respective phase winding set, and
M damping capacitor sets each of which includes a first capacitor coupled electrically between the node at which said first and second windings of a respective one of said phase winding sets are connected and the positive terminal of the DC power source, and a second capacitor coupled electrically between the node at which said first and second windings of the respective one of said phase winding sets are connected and the negative terminal of the DC power source;
wherein when said first switch and said second switch of one of said switching members are conducting, a corresponding one of said phase winding sets coupled electrically between said first and second switches of said one of said switching members is configured to form a current loop with the DC power source so as to generate a magnetic field for driving rotation of said rotor; and
wherein when said first switch and said second switch of said one of said switching members are not conducting, an instantaneous counter electromotive force (CEMF) induced at said first winding of the corresponding one of said phase winding sets charges said second capacitor of a respective one of said damping capacitor sets via said first flyback diode of said one of said switching members, and an instantaneous CEMF induced at said second winding of the corresponding one of said phase winding sets charges said first capacitor of the respective one of said damping capacitor sets via said second flyback diode of said one of said switching members.
2. The reluctance motor system according to claim 1, the DC power source being a storage battery,
wherein, for each of said damping capacitor sets, when a voltage across a series connection of said first capacitor and said second capacitor is greater than a voltage of the storage battery, said first capacitor and said second capacitor are configured to charge the storage battery.
3. The reluctance motor system according to claim 1, further comprising a rectifier-filter circuit which is coupled electrically between said driving circuit and an alternating current (AC) power source, and which rectifies and filters an AC output of the AC power source to serve as the DC power source that powers said reluctance motor system.
4. The reluctance motor system according to claim 1, wherein at least one of said first capacitor and said second capacitor of each of said damping capacitor sets is a non-polarized medium frequency capacitor that is configured to operate within a frequency band ranging from 300 to 1000 Hertz.
5. The reluctance motor system according to claim 1, wherein said stator includes 2\xd7M salient poles, said first winding and said second winding of each of said phase winding sets being respectively wound around two of said salient poles of said stator that are diametrically opposite to each other, said rotor including 2\xd7N projecting poles, N being an integer ranging from 2 to M.
6. The reluctance motor system according to claim 5, wherein said driving circuit further includes:
N resonant inductors each of which is wound around two of said projecting poles of said rotor that are diametrically opposite to each other;
N resonant capacitors each of which is connected in parallel with a respective one of said resonant inductors;
M third flyback diodes each of which is inversely connected in parallel with said first switch of a respective one of said switching members; and
M fourth flyback diodes each of which is inversely connected in parallel with said second switch of a respective one of said switching members;
wherein when said first switch and said second switch of one of said switching members of said driving circuit are conducting so that the corresponding one of said phase winding sets coupled electrically between said first and second switches of said one of said switching members is configured to form the current loop with the DC power source, a current flow is induced in one of said resonant inductors wound around two of said projecting poles of said rotor that are diametrically opposite to each other and that are adjacent in position to the corresponding one of said phase winding sets, and charges a corresponding one of said resonant capacitors; and
wherein when said first switch and said second switch of said one of said switching members are not conducting so that the corresponding one of said phase winding sets coupled electrically between said first and second switches of said one of said switching members is not configured to form the current loop with the DC power source, the corresponding one of said resonant capacitors discharges electricity into said one of said resonant inductors, such that a current flow is induced in said first winding of the corresponding one of said phase winding sets and charges said first capacitor of a respective one of said damping capacitor sets via said third flyback diode which is inversely connected in parallel with said first switch of said one of said switching members, and such that a current flow is induced in said second winding of the corresponding one of said phase winding sets and charges said second capacitor of the respective one of said damping capacitor sets via said fourth flyback diode which is inversely connected in parallel with said second switch of said one of said switching members.
7. The reluctance motor system according to claim 5,
wherein each of said salient poles of said stator has a distal end that widens toward said rotor and that curves toward a direction away from said rotor to form a concave surface; and
wherein each of said projecting poles of said rotor has a distal end that widens toward said stator and that curves toward said stator to forma convex surface which corresponds in shape to said concave surface.
8. A driving circuit for a reluctance motor, the reluctance motor including a stator and a rotor, the stator including M phase winding sets, M being an integer not smaller than 3, each of the phase winding sets including a first winding and a second winding that are disposed at diametrically opposite positions of the stator, and that are connected in series at a corresponding node, said driving circuit to be powered by a direct current (DC) power source, and comprising:
M switching members each of which is to be connected in parallel with the DC power source and each of which is to be coupled electrically to a respective one of the phase winding sets, each of said switching members including a first switch to be coupled electrically to a first end of the respective phase winding set, a second switch to be coupled electrically to a second end of said respective phase winding set opposite to the first end thereof, a first flyback diode with a cathode to be coupled electrically to the first end of said respective phase winding set and with an anode to be coupled electrically to a negative terminal of the DC power source, and a second flyback diode with a cathode to be coupled electrically to a positive terminal of the DC power source and with an anode to be coupled electrically to the second end of said respective phase winding set; and
M damping capacitor sets each of which includes a first capacitor to be coupled electrically between the node at which the first and second windings of a respective one of the phase winding sets are connected and the positive terminal of the DC power source, and a second capacitor to be coupled electrically between the node at which the first and second windings of the respective one of the phase winding sets are connected and the negative terminal of the DC power source;
wherein when said first switch and said second switch of one of said switching members are conducting, a corresponding one of the phase winding sets coupled electrically between said first and second switches of said one of said switching members is configured to form a current loop with the DC power source so as to generate a magnetic field for driving rotation of the rotor; and
wherein when said first switch and said second switch of said one of said switching members are not conducting, an instantaneous counter electromotive force (CEMF) induced at the first winding of the corresponding one of the phase winding sets charges said second capacitor of a respective one of said damping capacitor sets via said first flyback diode of said one of said switching members, and an instantaneous CEMF induced at the second winding of the corresponding one of the phase winding sets charges said first capacitor of the respective one of said damping capacitor sets via said second flyback diode of said one of said switching members.
9. A reluctance motor comprising:
a stator including 2\xd7M salient poles and M phase winding sets, M being an integer not smaller than 3, each of said phase winding sets including a first winding and a second winding which are respectively wound around two of said salient poles of said stator that are diametrically opposite to each other, and which are connected in series; and
a rotor surrounded by said stator and including 2\xd7N projecting poles, N being an integer ranging from 2 to M;
wherein each of said salient poles of said stator has a distal end that widens toward said rotor and that curves toward a direction away from said rotor to form a concave surface; and
wherein each of said projecting poles of said rotor has a distal end that widens toward said stator and that curves toward said stator to forma convex surface which corresponds in shape to said concave surface.
10. The reluctance motor according to claim 9, further comprising:
N resonant inductors each of which is wound around two of said projecting poles of said rotor that are diametrically opposite to each other; and
N resonant capacitors each of which is connected in parallel with a respective one of said resonant inductors.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A computer-implemented method comprising:
determining a first measure of a first corpus for a search query as a count of times the search query was submitted to search the first corpus in view of a count of times other queries were submitted to search the first corpus;
determining a second measure of a second corpus for the search query as a count of times the search query was submitted to search the second corpus in view of a count of times other queries were submitted to search the second corpus;
determining a click measure based on a count of selections of first corpus search results for the search query relative to a count of selections of second corpus search results for the search query;
determining a measure of relative relevance of the first corpus and the second corpus for the search query based on the first measure, the second measure and the click measure; and
providing the measure of relative relevance to a ranking engine for ranking of search results for a search corresponding to the search query.
2. The method of claim 1 wherein determining the first measure of the first corpus for the search query further comprises determining the first measure by combining a plurality of relevance determinations wherein each relevance determination in the plurality is for a different time period.
3. The method of claim 1 wherein determining the first measure of the first corpus for the search query comprises determining the count of times the search query was submitted to search the first corpus in view of the count of times all queries were submitted to search the first corpus.
4. The method of claim 1 wherein determining the measure of relative relevance of the first corpus and the second corpus for the search query comprises determining the first measure of the first corpus as compared to the second measure of the second corpus.
5. The method of claim 1 wherein determining the measure of relative relevance comprises computing a weighted combination of a relative search fraction of the first measure and the second measure, and the click measure.
6. The method of claim 1 wherein the respective counts for the first and second corpora are derived from language-specific data or country-specific data, and wherein determining a relevance of a corpus for the search query further comprises selecting which of the data to use for the respective counts based on a determination that the selected data will provide a reliable statistic.
7. The method of claim 1 wherein the first corpus comprises web pages and wherein the second corpus comprises videos.
8. The method of claim 1 wherein the first corpus comprises web pages and wherein the second corpus comprises images.
9. The method of claim 1 wherein the ranking engine is configured to increase a score of a search result for the search that refers to a document in the second corpus based at least in part on the measure of relative relevance.
10. A system comprising:
a storage device having instructions stored thereon; and
data processing apparatus operable to execute the instructions to perform operations comprising:
determining a first measure of a first corpus for a search query as a count of times the search query was submitted to search the first corpus in view of a count of times other queries were submitted to search the first corpus;
determining a second measure of a second corpus for the search query as a count of times the search query was submitted to search the second corpus in view of a count of times other queries were submitted to search the second corpus;
determining a click measure based on a count of selections of first corpus search results for the search query relative to a count of selections of second corpus search results for the search query;
determining a measure of relative relevance of the first corpus and the second corpus for the search query based on the first measure, the second measure and the click measure; and
providing the measure of relative relevance to a ranking engine for ranking of search results for a search corresponding to the search query.
11. The system of claim 10 wherein determining the first measure of the first corpus for the search query further comprises determining the first measure by combining a plurality of relevance determinations wherein each relevance determination in the plurality is for a different time period.
12. The system of claim 10 wherein determining the first measure of the first corpus for the search query comprises determining the count of times the search query was submitted to search the first corpus in view of the count of times all queries were submitted to search the first corpus.
13. The system of claim 10 wherein determining the measure of relative relevance of the first corpus and the second corpus for the search query comprises determining the first measure of the first corpus as compared to the second measure of the second corpus.
14. The system of claim 10 wherein determining the measure of relative relevance comprises computing a weighted combination of a relative search fraction of the first measure and the second measure, and the click measure.
15. The system of claim 10 wherein the respective counts for the first and second corpora are derived from language-specific data or country-specific data, and wherein determining a relevance of a corpus for the search query further comprises selecting which of the data to use for the respective counts based on a determination that the selected data will provide a reliable statistic.
16. The system of claim 10 wherein the first corpus comprises web pages and wherein the second corpus comprises videos.
17. The system of claim 10 wherein the first corpus comprises web pages and wherein the second corpus comprises images.
18. The system of claim 10 wherein the ranking engine is configured to increase a score of a search result for the search that refers to a document in the second corpus based at least in part on the measure of relative relevance.
19. A storage device having instructions stored thereon that, when executed by data processing apparatus, cause the data processing apparatus to perform operations comprising:
determining a first measure of a first corpus for a search query as a count of times the search query was submitted to search the first corpus in view of a count of times other queries were submitted to search the first corpus;
determining a second measure of a second corpus for the search query as a count of times the search query was submitted to search the second corpus in view of a count of times other queries were submitted to search the second corpus;
determining a click measure based on a count of selections of first corpus search results for the search query relative to a count of selections of second corpus search results for the search query;
determining a measure of relative relevance of the first corpus and the second corpus for the search query based on the first measure, the second measure and the click measure; and
providing the measure of relative relevance to a ranking engine for ranking of search results for a search corresponding to the search query.
20. The storage device of claim 19 wherein determining the first measure of the first corpus for the search query further comprises determining the first measure by combining a plurality of relevance determinations wherein each relevance determination in the plurality is for a different time period.
21. The storage device of claim 19 wherein determining the first measure of the first corpus for the search query comprises determining the count of times the search query was submitted to search the first corpus in view of the count of times all queries were submitted to search the first corpus.
22. The storage device of claim 19 wherein determining the measure of relative relevance of the first corpus and the second corpus for the search query comprises determining the first measure of the first corpus as compared to the second measure of the second corpus.
23. The storage device of claim 19 wherein determining the measure of relative relevance comprises computing a weighted combination of a relative search fraction of the first measure and the second measure, and the click measure.
24. The storage device of claim 19 wherein the respective counts for the first and second corpora are derived from language-specific data or country-specific data, and wherein determining a relevance of a corpus for the search query further comprises selecting which of the data to use for the respective counts based on a determination that the selected data will provide a reliable statistic.
25. The storage device of claim 19 wherein the first corpus comprises web pages and wherein the second corpus comprises videos.
26. The storage device of claim 19 wherein the first corpus comprises web pages and wherein the second corpus comprises images.
27. The storage device of claim 19 wherein the ranking engine is configured to increase a score of a search result for the search that refers to a document in the second corpus based at least in part on the measure of relative relevance.