JP2004032918A

JP2004032918A - Permanent magnet rotary electric machine

Info

Publication number: JP2004032918A
Application number: JP2002186490A
Authority: JP
Inventors: Hideaki Otsuka; 大塚　英明
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 2002-06-26
Filing date: 2002-06-26
Publication date: 2004-01-29

Abstract

<P>PROBLEM TO BE SOLVED: To provide a permanent magnet type rotary electric machine for restraining excessive induced voltage during the time of high rotational speed, and gaining large reluctance torque. <P>SOLUTION: This rotary electric machine comprises a stator 11 which is disposed with a stator winding 13 on an inner periphery surface of a roughly cylindrical stator core 12, and a rotor 14 supported rotatably on an inner periphery side of the stator 11 through a prescribed gap G. This rotor 14 has a columnar rotor core 15, a rotating shaft 19 which is pierced at a position connecting centers of a circular plate of both end surfaces in an axial direction of the rotor core 15, at least two pairs of rotor poles consisting of plate type permanent magnets 16 buried in a part, which is the rotor core 15, facing an outer periphery surface of the rotating shaft 19 and the inner periphery surface of the stator core 12, and disposed so that the respective pairs may become a roughly V shape when viewed from a cross section orthogonal to the axial direction respectively and the corner part of the V shape may face the rotating shaft 19 side, and a plurality of roughly V-shaped slits 17 or a plurality of holes 18 formed at a position, which is the rotor core 15, facing the permanent magnet 16 and the stator core 12 so as to be in parallel to the rotor poles respectively. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、ほぼ円柱状の回転子鉄心の軸方向に複数の永久磁石を埋め込んで回転子磁極が構成された回転子を有する永久磁石型回転電機に関する。
【０００２】
【従来の技術】
この種従来の永久磁石型回転電機の一例として、特開平１１−２７９１３号公報（第１の公知例）で開示されており、図６及び図７はこれを説明するための図である。すなわち、固定子１は、ほぼ円筒状の固定子鉄心２の内周側に形成されている複数の固定子巻線収納部２ａに夫々固定子巻線３が巻装されている。固定子鉄心２の内周側には空隙Ｇを介して回転子４が回転可能に設けられている。
【０００３】
この回転子４は、図７に示すようにほぼ円柱状の回転子鉄心５の軸方向に、回転子鉄心５の軸方向端面の円板の中心を結ぶ線上に貫通固定された回転軸１９と、回転子鉄心５であって回転軸の外周面と固定子鉄心２の内周面と対向する部分に、軸方向に沿って埋設され、軸方向と直交する断面から見たときほぼＶ字状であって、該Ｖ字の角部が回転軸１９側に向くように配設された２枚の板状の永久磁石６で１個の回転子磁極（回転子磁石極）を構成し、この回転子磁極が例えば４組からなり、回転子鉄心５の永久磁石６と回転子鉄心５の外周面で挟まれた部分に形成し、内部を空洞（空隙）とした軸方向断面が扇状の孔７とで構成されている。なお、各回転子磁極を構成する２枚の永久磁石６は、Ｎ極とＳ極とが交互になるように着磁されている。
【０００４】
【発明が解決しようとする課題】
しかしながら、第１の公知例では孔７によって永久磁石６により発生する磁束が制限され、高回転数時における過大な誘起電圧を抑制する効果があるものの、孔７が固定子巻線３を流れる電流が作る磁極軸方向を通過する磁極軸方向磁束Ｂ１と磁極軸間方向を通過する磁極軸間方向磁束Ｂ２の両方を妨げる働きをするので、回転子４の磁極軸方向と磁極軸間方向の磁気抵抗差が大きくならず、大きなリラクタンストルクが得られない。その結果、永久磁石６によって発生するトルクとリラクタンストルクの総合トルクが大きくならないという問題があった。
【０００５】
以上述べた第１の公知例の問題点を改善するため、次のように構成した第２の公知例（特開２０００−３２７１８号公報）、第３の公知例（特開２０００−３２６９１号公報）、第４の公知例（特開平１１−２０６０４６号公報）、第４の公知例（特開平１１−１３６８９２号公報）、第５の公知例（特開平１１−１３６９１２号公報）がある。
【０００６】
このうち第２及び第３の公知例は、いずれも回転子鉄心の外周面側、つまり固定子鉄心の内周面側に対向する側に軸方向断面が扇状の永久磁石を形成し、かつこの永久磁石と回転軸の間に、変形Ｖ字状又はＩ字状のスリットを形成したものである。このように構成することにより、何等かの理由で回転子の外周側から永久磁石に対して強い逆磁界がかかった場合には、この逆磁界により永久磁石の磁界が相殺され、本来必要な永久磁石の磁束量が減少することから、所望の磁束量を得るためには永久磁石の体積を増やす必要が生じる。
【０００７】
また、第４の公知例は、円柱状の回転子鉄心の回転軸の周囲で軸方向に永久磁石が埋設され、該永久磁石と回転子鉄心の外周面の間に放射状の貫通孔が形成されているものであり、このような構成であるため第２及び第３の公知例の問題点は除去できるものの、該貫通孔によって回転子の回転方向が限定されるという問題点が新たに生ずる。
【０００８】
さらに、第５の公知例は、円筒状の第１及び第２のコアが同一面に並設され、第１のコアは磁石トルクを出すためのものであり、第２のコアはリラクタンストルクを出すためのものであり、この２種類のコアを同軸上に組み合わせたものであり、この場合にはコアを２種類必要とすることから、部品点数及び工程数が多くなるという問題がある。
【０００９】
本発明は以上のような事情に基づいてなされたものであり、その目的は高回転数時の過大な誘起電圧を抑制することができて、大きなリラクタンストルクを得ることができ、永久磁石の体積や部品点数、工程数を増やすことがなく、回転方向等の制約条件がなく、総合トルクを大きくすることができる永久磁石型回転電機を提供することにある。
【００１０】
【課題を解決するための手段】
前記目的を達成するため、請求項１に対応する発明は、円筒状の固定子鉄心の内周面に固定子巻線が配設された固定子と、該固定子の内周側に所定の空隙を介して回転可能に支持された回転子とからなる永久磁石型回転電機において、前記回転子は、円柱状の回転子鉄心と、前記回転子鉄心の軸方向両端面の中心同士を結んだ位置に貫通配設された回転軸と、前記回転子鉄心の内部に前記回転軸と平行に夫々埋設され、各組は各々軸方向と直交する断面で見たときほぼＶ字状であって、該Ｖ字の角部が前記回転軸側に向くように配設された板状の永久磁石からなる少なくとも２組の回転子磁極と、前記回転子鉄心に設けられ、前記各回転子磁極に沿うように前記回転子磁極の外周面側にほぼＶ字状に形成された磁気抵抗形成部とを具備した永久磁石型回転電機である。
【００１１】
前記目的を達成するため、請求項３に対応する発明は、円筒状の固定子鉄心の内周面に固定子巻線が配設された固定子と、該固定子の内周側に所定の空隙を介して回転可能に支持された回転子とからなる永久磁石型回転電機において、前記回転子は、円柱状の回転子鉄心と、前記回転子鉄心の軸方向両端面の中心同士を結んだ位置に貫通配設された回転軸と、前記回転子鉄心の内部に前記回転軸と平行に夫々埋設され、各組は各々軸方向と直交する断面で見たときほぼＶ字状であって、該Ｖ字の角部が前記回転軸側に向くように配設された板状の永久磁石からなる少なくとも２組の回転子磁極と、前記回転子鉄心に設けられ、前記各回転子磁極に沿うように前記回転子磁極の外周面側にほぼＶ字状に形成された複数のスリット又は複数の穴とを具備した永久磁石型回転電機である。
【００１２】
前記目的を達成するため、請求項４に対応する発明は、円筒状の固定子鉄心の内周面に固定子巻線が配設された固定子と、該固定子の内周側に所定の空隙を介して回転可能に支持された回転子とからなる永久磁石型回転電機において、前記回転子は、円柱状の回転子鉄心と、前記回転子鉄心の軸方向両端面の中心同士を結んだ位置に貫通配設された回転軸と、前記回転子鉄心の内部に前記回転軸と平行に夫々埋設され、各組は各々軸方向と直交する断面で見たときほぼＶ字状であって、該Ｖ字の角部が前記回転軸側に向くように配設された板状の永久磁石からなる少なくとも２組の回転子磁極と、前記回転子磁極の各組に対して複数設けられ、その回転子磁極の該Ｖ字の角部と前記回転軸とを結ぶ磁極軸に対称に形成される各々内部を空隙とした孔とを具備した永久磁石型回転電機である。
【００１３】
請求項１、３、４のいずれかに対応する発明によれば、回転子鉄心の永久磁石に囲まれる部分に磁気抵抗形成部を形成したので、磁気抵抗形成部と永久磁石の間の部分が磁気飽和を起こすことによって永久磁石の磁束を制限し、固定子巻線を鎖交する磁束を低減することで過大な誘起電圧を抑制することができ、また、磁気抵抗形成部が固定子電流が作る磁極軸方向を通過する磁束を妨げ、磁極軸間方向を通過する磁束を妨げないことから、磁極軸方向の磁気抵抗は高く、磁極軸間方向の磁気抵抗は低くなって、リラクタンストルクを大きくできる。
【００１４】
【発明の実施の形態】
以下、図面を参照して本発明の実施形態を説明する。
【００１５】
始めに、本発明に係る永久磁石型回転電機の第１の実施形態について図１および２を参照しながら説明する。固定子１１は、ほぼ円筒状の固定子鉄心１２の内周面に形成された固定子巻線収納部１２ａに、固定子巻線１３が収納されており、これは図６の構成と同一である。
【００１６】
図６と異なる点は以下に述べる回転子の構成である。回転子１４は、固定子１１の内周側に所定の空隙Ｇを介して回転可能に支持されたものであって、以下のように構成されている。回転子１４は、円柱状の回転子鉄心１５と、回転子鉄心１５の軸方向両端面の円板の中心同士を結んだ位置に貫通配設された回転軸１９と、回転子鉄心１５に設けられ、回転軸１９の外周面と固定子鉄心１２の内周面と対向する部分でかつ軸方向に夫々埋設され、各組は各々軸方向と直交する断面から見たときほぼＶ字状であって、該Ｖ字の角部が回転軸１９側に向くように夫々形成された収容空間部１５ａ内に配設された板状の永久磁石１６からなる少なくとも２組（本実施形態では４組）の回転子磁極と、回転子鉄心１５に設けられ、各回転子磁極と固定子鉄心１２とに対向する位置で各回転子磁極に沿うように回転子軸１９の外周面側にほぼＶ字状に形成された磁気抵抗形成部、言い換えると回転子鉄心１５に設けられ、各回転子磁極と前記固定子鉄心とに対向する位置で各回転子磁極に対してそれぞれほぼ平行に形成され、各回転子磁極の磁極軸方向の磁気抵抗を回転子鉄心１５に比べて大きくし、かつ該各回転子磁極の磁極軸間方向の磁気抵抗を回転子鉄心１５に比べて小さくするための磁気抵抗形成部とを具備したものである。
【００１７】
磁気抵抗形成部は、具体的には以下に述べるスリット（細長い穴又は孔）１７、該スリット１７に非磁性材料を充填したもの、複数の穴（孔）１８に非磁性材料を充填したもの、穴１８と複数のスリット１７ａの組合わせからなるもの、穴１８と複数のスリット１７ａの組合わせたもので穴１８とスリット１７ａに夫々非磁性材料を充填したもの、これらのいずれかで構成したものである。
【００１８】
第１の実施形態は、磁気抵抗形成部として、図１及び図２に示すように複数のスリット１７を形成したものである。具体的には、回転子鉄心１５であって各永久磁石１６と固定子鉄心１２の対向する位置に各永久磁石１６に対してそれぞれ平行に形成されたほぼＶ字状の複数のスリット（空洞）１７を形成したものである。
【００１９】
以上述べた第１の本実施形態によれば、回転子鉄心１５の永久磁石１６に囲まれる部分には永久磁石１６の配置に沿って内部を空洞としたスリット１７を形成したから、回転子鉄心１５のスリット１７と永久磁石１６の間の部分が磁気飽和を起こすことによって永久磁石１６の磁束を制限し、固定子巻線１３を鎖交する磁束を低減することで過大な誘起電圧を抑制することができ、また、スリット１７が固定子電流が作る磁極軸方向を通過する磁束Ｂ１を妨げ、磁極軸間方向を通過する磁束Ｂ２を妨げないことから、磁極軸方向の磁気抵抗は高く、磁極軸間方向の磁気抵抗は低くなって、リラクタンストルクを大きくできる。
【００２０】
なお、この場合の磁極軸は、各磁石極における永久磁石１６の接触部のうち対向するもの同士を結ぶ直線のことである。
【００２１】
ここで、永久磁石式回転電機のトルクＴは式（１）で示される。
【００２２】
Ｔ＝Ｐ｛φｉｑ＋（Ｌｄ−Ｌｑ）ｉｄｉｑ｝　　　　（１）
Ｐ：極対数、φ：永久磁石による鎖交磁束、Ｌｄ：磁極軸方向のインダクタンス、Ｌｑ：磁極軸間方向のインダクタンス、ｉｄ：固定子巻線電流の磁極軸方向成分、ｉｑ：固定子巻線電流の磁極間軸方向成分。
【００２３】
一般に磁気抵抗が低ければインダクタンスは高くなり、スリット１７によって磁極軸方向の磁気抵抗が高く、磁極軸間方向の磁気抵抗が低くなることから、磁極軸方向のインダクタンスは低く、磁極軸間方向のインダクタンスは高くなる。スリット１７により固定子巻線１３を鎖交する磁束が低くなるので、（１）式第１項は小さくなるが、インダクタンス差が大きくなるので第２項は大きくなり、総合トルク自体は大きくできる。
【００２４】
従って、第１の実施形態では、高回転数時において誘起電圧を高くすることなく高トルクを得ることができる。
【００２５】
第２の実施形態は、磁気抵抗形成部として、図３に示すように前述した第１の実施形態のスリット１７を形成せず、このスリット１７の形成されている部分に、次のような複数の孔１８を形成したものである。回転子鉄心１５に埋設されている永久磁石１６と回転子鉄心１５の外周面との間であって、各永久磁石１６に対して平行になるようにの配置に沿って内部を空隙とした複数の孔１８を磁極軸を中心に対称に形成している。
【００２６】
この第２の実施形態においても高回転数時において誘起電圧を高くすること無く高トルクを得ることができる。この場合、図１及び図２に示すようなスリット１７ではなく、複数の孔１８であることから回転子鉄心１５は強度的に強くなる。
【００２７】
第３の実施形態は、磁気抵抗形成部として、図４に示すように、この第３の実施形態を次のようにしたものである。すなわち、回転子鉄心１５の永久磁石１６に囲まれる部分の磁極軸上に内部を空洞とした孔１８を形成し、前記孔１８を中心に永久磁石１６の配置に沿って複数のスリット１７ａを形成している。
【００２８】
この第３の実施形態においても高回転数時において誘起電圧を高くすること無く高トルクを得ることができる。特に、磁極軸上に必ず孔１８を設けることにより高回転数時の応力の集中を防ぐことができ、また、複数のスリット１７ａおよび孔１８であることから回転子鉄心１５は強度的に強くなる。
【００２９】
第４の実施形態は、図５に示すように、各回転子磁極を構成する永久磁石１６の両端部と回転軸１９中心を結ぶ線で形成される角度が、磁極軸を中心に電気角で１１５〜１２０度の範囲に形成したものである。これは、前述の第１〜第３の実施形態の全てに適用できる。
【００３０】
この第４の実施形態においても高回転数時において誘起電圧を高くすること無く高トルクを得ることができる。特に、永久磁石１６が形成する磁極の両端部と回転軸１９中心とがなす角度を磁極軸を中心に電気角１１５〜１２０度の範囲にすることで磁極間軸上の突極性が大きくなり、より大きなリラクタンストルクを発生することができる。
【００３１】
第５の実施形態は、第１の実施形態のスリット１７、第２の実施形態の孔１８、第３の実施形態のスリット１７及び孔１８のいずれか叉はこれらの全てに非磁性材のステンレスを埋め込んだものである。このように構成することにより、前述の各実施形態での効果が得られることは言うまでもなく、スリット１７叉はおよび孔１８に非磁性材のステンレスを埋め込んだ分機械的強度が向上する。
【００３２】
第６の実施形態は、第１の実施形態のスリット１７、第２の実施形態の孔１８、第３の実施形態のスリット１７及び孔１８のいずれか叉はこれらの全てに、導電性の非磁性材例えば銅またはアルミニウムを埋め込んだものである。第６の実施形態によれば、前述の各実施形態での効果が得られることは言うまでもなく、過渡的に非同期になったときに充填された導電性の非磁性材に電流が流れ、安定して回転する。
【００３３】
【発明の効果】
本発明によれば、高回転数時の過大な誘起電圧を抑制することができて、大きなリラクタンストルクを得ることができ、永久磁石の体積や部品点数、工程数を増やすことがなく、回転方向等の制約条件がなく、総合トルクを大きくすることできる永久磁石型回転電機を提供することができる。
【図面の簡単な説明】
【図１】本発明の永久磁石型回転電機の第１の実施形態を示す縦断面図。
【図２】図１の回転子のみを拡大して示す縦断面図。
【図３】本発明の永久磁石型回転電機の第２の実施形態における回転子のみを拡大して示す縦断面図。
【図４】本発明の永久磁石型回転電機の第３の実施形態における回転子のみを拡大して示す縦断面図。
【図５】本発明の永久磁石型回転電機の第４の実施形態における回転子のみを拡大して示す縦断面図。
【図６】従来の永久磁石型回転電機の一例を示す縦断面図。
【図７】図６の回転子のみを拡大して示す縦断面図。
【符号の説明】
１…固定子
２…固定子鉄心
２ａ…固定子巻線収納部
３…固定子巻線
４…回転子
５…回転子鉄心
６…永久磁石
７…孔
１１…固定子
１２…固定子鉄心
１２ａ…固定子巻線収納部
１３…固定子巻線
１４…回転子
１５…回転子鉄心
１５ａ…収容空間部
１６…永久磁石
１７…スリット
１７ａ…スリット
１８…穴
１８…孔
１９…回転軸[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a permanent magnet type rotating electric machine having a rotor in which a plurality of permanent magnets are embedded in a substantially cylindrical rotor core in an axial direction to form a rotor magnetic pole.
[0002]
[Prior art]
An example of this type of conventional permanent magnet type rotating electric machine is disclosed in Japanese Patent Application Laid-Open No. H11-27913 (first known example), and FIGS. 6 and 7 are diagrams for explaining this. That is, in the stator 1, the stator windings 3 are respectively wound around a plurality of stator winding storage portions 2 a formed on the inner peripheral side of the substantially cylindrical stator core 2. A rotor 4 is rotatably provided on the inner peripheral side of the stator core 2 via a gap G.
[0003]
As shown in FIG. 7, the rotor 4 has a rotating shaft 19 fixedly penetrated in the axial direction of the substantially cylindrical rotor core 5 on a line connecting the center of the disk at the axial end surface of the rotor core 5. The rotor core 5 is buried along the axial direction in a portion facing the outer peripheral surface of the rotating shaft and the inner peripheral surface of the stator core 2, and is substantially V-shaped when viewed from a cross section orthogonal to the axial direction. A single rotor magnetic pole (rotor magnet pole) is constituted by two plate-shaped permanent magnets 6 arranged so that the corners of the V-shape face the rotation shaft 19 side. The rotor magnetic poles are composed of, for example, four sets, and are formed at a portion between the permanent magnet 6 of the rotor core 5 and the outer peripheral surface of the rotor core 5 and have a fan-shaped axial section with a cavity (gap) inside. 7. The two permanent magnets 6 constituting each rotor magnetic pole are magnetized such that N poles and S poles are alternated.
[0004]
[Problems to be solved by the invention]
However, in the first known example, the magnetic flux generated by the permanent magnet 6 is limited by the hole 7, and although there is an effect of suppressing an excessive induced voltage at a high rotation speed, the hole 7 has a current flowing through the stator winding 3. And a magnetic pole axis direction magnetic flux B1 passing through the magnetic pole axis direction and a magnetic pole axis direction magnetic flux B2 passing through the magnetic pole axis direction. The resistance difference does not increase, and a large reluctance torque cannot be obtained. As a result, there is a problem that the total torque of the torque generated by the permanent magnet 6 and the reluctance torque does not increase.
[0005]
In order to improve the problems of the first known example described above, a second known example (Japanese Patent Application Laid-Open No. 2000-32718) and a third known example (Japanese Patent Application Laid-Open No. 2000-32691) configured as follows. ), A fourth known example (JP-A-11-206046), a fourth known example (JP-A-11-136892), and a fifth known example (JP-A-11-136912).
[0006]
Of these, the second and third known examples both form a permanent magnet having a fan-shaped cross section in the axial direction on the outer peripheral surface side of the rotor core, that is, on the side facing the inner peripheral surface side of the stator core. A modified V-shaped or I-shaped slit is formed between the permanent magnet and the rotating shaft. With this configuration, if a strong reverse magnetic field is applied to the permanent magnet from the outer peripheral side of the rotor for some reason, the magnetic field of the permanent magnet is canceled by the reverse magnetic field, and the permanent magnetic field that is originally required is removed. Since the amount of magnetic flux of the magnet decreases, it is necessary to increase the volume of the permanent magnet to obtain a desired amount of magnetic flux.
[0007]
In the fourth known example, a permanent magnet is buried axially around a rotation axis of a cylindrical rotor core, and a radial through hole is formed between the permanent magnet and the outer peripheral surface of the rotor core. Although such a configuration can eliminate the problems of the second and third known examples, a new problem arises in that the rotation direction of the rotor is limited by the through holes.
[0008]
Further, in a fifth known example, cylindrical first and second cores are arranged side by side on the same surface, the first core is for generating magnet torque, and the second core is for generating reluctance torque. In this case, the two types of cores are coaxially combined. In this case, two types of cores are required, so that there is a problem that the number of parts and the number of steps are increased.
[0009]
The present invention has been made based on the above circumstances, and its object is to suppress an excessive induced voltage at a high rotation speed, obtain a large reluctance torque, and reduce the volume of the permanent magnet. It is an object of the present invention to provide a permanent magnet type rotating electric machine that can increase the total torque without increasing the number of parts, the number of steps, the number of steps, and having no restrictions such as the rotating direction.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, an invention corresponding to claim 1 includes a stator in which a stator winding is disposed on an inner peripheral surface of a cylindrical stator core, and a predetermined stator on an inner peripheral side of the stator. In a permanent magnet type rotating electric machine including a rotor rotatably supported via an air gap, the rotor connects a cylindrical rotor core and centers of both axial end faces of the rotor core. A rotating shaft disposed at a position penetrating therethrough, and embedded in the rotor core in parallel with the rotating shaft, and each set is substantially V-shaped when viewed in a cross section orthogonal to the axial direction, At least two sets of rotor magnetic poles made of plate-like permanent magnets arranged so that the corners of the V-shape face the rotation axis side, and provided on the rotor core, along the rotor magnetic poles And a magnetic resistance forming portion formed substantially in a V-shape on the outer peripheral surface side of the rotor magnetic pole. A magnet rotating electric machine.
[0011]
In order to achieve the above object, an invention corresponding to claim 3 includes a stator in which a stator winding is disposed on an inner peripheral surface of a cylindrical stator core, and a predetermined stator on an inner peripheral side of the stator. In a permanent magnet type rotating electric machine including a rotor rotatably supported via an air gap, the rotor connects a cylindrical rotor core and centers of both axial end faces of the rotor core. A rotating shaft disposed at a position penetrating therethrough, and embedded in the rotor core in parallel with the rotating shaft, and each set is substantially V-shaped when viewed in a cross section orthogonal to the axial direction, At least two sets of rotor magnetic poles made of plate-like permanent magnets arranged so that the corners of the V-shape face the rotation axis side, and provided on the rotor core, along the rotor magnetic poles A plurality of slits or a plurality of holes formed in a substantially V-shape on the outer peripheral surface side of the rotor magnetic pole. A permanent magnet type rotary electric machine equipped.
[0012]
In order to achieve the above object, an invention corresponding to claim 4 includes a stator in which a stator winding is disposed on an inner peripheral surface of a cylindrical stator core, and a predetermined stator on an inner peripheral side of the stator. In a permanent magnet type rotating electric machine including a rotor rotatably supported via an air gap, the rotor connects a cylindrical rotor core and centers of both axial end faces of the rotor core. A rotating shaft disposed at a position penetrating therethrough, and embedded in the rotor core in parallel with the rotating shaft, and each set is substantially V-shaped when viewed in a cross section orthogonal to the axial direction, At least two sets of rotor magnetic poles made of plate-like permanent magnets arranged so that the V-shaped corners face the rotation axis side, and a plurality of rotor magnetic poles are provided for each set of the rotor magnetic poles. A gap is formed inside each of the rotor magnetic poles formed symmetrically with respect to a magnetic pole axis connecting the V-shaped corner and the rotation axis. It pores and a permanent magnet type rotary electric machine provided with the.
[0013]
According to the invention corresponding to any one of the first, third, and fourth aspects, since the magnetoresistive forming portion is formed in the portion of the rotor core surrounded by the permanent magnet, the portion between the magnetoresistive forming portion and the permanent magnet is formed. By causing magnetic saturation, the magnetic flux of the permanent magnet is limited, and the magnetic flux linking the stator windings is reduced, so that excessive induced voltage can be suppressed. Since the magnetic flux passing through the magnetic pole axis direction is not blocked and the magnetic flux passing through the magnetic pole axis direction is not blocked, the magnetic resistance in the magnetic pole axis direction is high, and the magnetic resistance in the magnetic pole axis direction is low, increasing the reluctance torque. it can.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0015]
First, a first embodiment of a permanent magnet type rotating electric machine according to the present invention will be described with reference to FIGS. In the stator 11, a stator winding 13 is accommodated in a stator winding accommodating portion 12a formed on an inner peripheral surface of a substantially cylindrical stator core 12, which is the same as the configuration in FIG. is there.
[0016]
The difference from FIG. 6 is the configuration of the rotor described below. The rotor 14 is rotatably supported on the inner peripheral side of the stator 11 via a predetermined gap G, and is configured as follows. The rotor 14 is provided on the cylindrical rotor core 15, a rotary shaft 19 penetratingly disposed at a position connecting the centers of the disks on both axial end surfaces of the rotor core 15, and the rotor core 15. The parts are buried in the axial direction at portions facing the outer peripheral surface of the rotating shaft 19 and the inner peripheral surface of the stator core 12, and each set is substantially V-shaped when viewed from a cross section orthogonal to the axial direction. At least two sets (four in the present embodiment) of plate-shaped permanent magnets 16 disposed in the accommodation space portions 15a formed so that the V-shaped corners face the rotation shaft 19, respectively. And a substantially V-shape on the outer peripheral surface side of the rotor shaft 19 along the respective rotor magnetic poles at a position facing the respective rotor magnetic poles and the stator core 12 and provided on the rotor core 15. In other words, each of the magnetic poles provided on the rotor core 15 The rotor magnetic poles are formed substantially parallel to the respective rotor magnetic poles at positions opposed to the stator core, so that the magnetic resistance of each rotor magnetic pole in the magnetic pole axis direction is larger than that of the rotor core 15, and And a magnetic resistance forming portion for reducing the magnetic resistance between the magnetic pole axes of the daughter magnetic poles in comparison with the rotor core 15.
[0017]
The magnetoresistive forming portion includes a slit (elongated hole or hole) 17 described below, a material in which the slit 17 is filled with a non-magnetic material, a material in which a plurality of holes (holes) 18 are filled with a non-magnetic material, A combination of the hole 18 and the plurality of slits 17a, a combination of the hole 18 and the plurality of slits 17a, each of which is filled with a non-magnetic material in the hole 18 and the slit 17a, or a combination of any of these. It is.
[0018]
In the first embodiment, a plurality of slits 17 are formed as a magnetic resistance forming portion as shown in FIGS. More specifically, a plurality of substantially V-shaped slits (cavities) formed in the rotor core 15 at positions opposed to the respective permanent magnets 16 and the stator core 12 in parallel with the respective permanent magnets 16. 17 is formed.
[0019]
According to the first embodiment described above, the slit 17 having a hollow inside is formed in the portion of the rotor core 15 surrounded by the permanent magnet 16 along the arrangement of the permanent magnet 16. The portion between the slit 17 of 15 and the permanent magnet 16 causes magnetic saturation, thereby restricting the magnetic flux of the permanent magnet 16 and reducing the magnetic flux linking the stator winding 13 to suppress an excessive induced voltage. Further, since the slit 17 prevents the magnetic flux B1 passing through the magnetic pole axis direction created by the stator current and does not prevent the magnetic flux B2 passing through the direction between the magnetic pole axes, the magnetic resistance in the magnetic pole axis direction is high, The reluctance torque can be increased by lowering the magnetic resistance in the inter-axis direction.
[0020]
Note that the magnetic pole axis in this case is a straight line connecting the opposing parts of the contact portions of the permanent magnets 16 in each magnet pole.
[0021]
Here, the torque T of the permanent magnet type rotating electric machine is expressed by equation (1).
[0022]
T = P {φiq + (Ld−Lq) idiq} (1)
P: number of pole pairs, φ: flux linkage by permanent magnet, Ld: inductance in the direction of the magnetic pole axis, Lq: inductance in the direction between the magnetic pole axes, id: component of the stator winding current in the magnetic pole axis direction, iq: stator winding The axial component of the current between the magnetic poles.
[0023]
In general, the lower the magnetic resistance, the higher the inductance. The slit 17 increases the magnetic resistance in the magnetic pole axis direction and decreases the magnetic resistance between the magnetic pole axes. Therefore, the inductance in the magnetic pole axis direction is low, and the inductance in the magnetic pole axis direction. Will be higher. Since the magnetic flux linking the stator winding 13 by the slit 17 is reduced, the first term of the equation (1) is reduced, but the inductance difference is increased, so the second term is increased, and the total torque itself can be increased.
[0024]
Therefore, in the first embodiment, a high torque can be obtained without increasing the induced voltage at a high rotation speed.
[0025]
In the second embodiment, as shown in FIG. 3, the slit 17 of the above-described first embodiment is not formed as a magnetoresistive forming portion. The hole 18 is formed. Between the permanent magnet 16 buried in the rotor core 15 and the outer peripheral surface of the rotor core 15, a plurality of voids are formed inside along an arrangement parallel to each permanent magnet 16. Are formed symmetrically about the magnetic pole axis.
[0026]
Also in the second embodiment, a high torque can be obtained without increasing the induced voltage at a high rotation speed. In this case, the rotor core 15 is strengthened in strength because it has a plurality of holes 18 instead of the slits 17 as shown in FIGS.
[0027]
In the third embodiment, as shown in FIG. 4, the third embodiment is the following as the magnetoresistive forming section. That is, a hole 18 having a hollow inside is formed on the magnetic pole axis of a portion of the rotor core 15 surrounded by the permanent magnet 16, and a plurality of slits 17 a are formed around the hole 18 along the arrangement of the permanent magnet 16. are doing.
[0028]
Also in the third embodiment, a high torque can be obtained at a high rotation speed without increasing the induced voltage. In particular, by always providing the hole 18 on the magnetic pole axis, concentration of stress at a high rotation speed can be prevented, and the rotor core 15 becomes strong in strength because of the plurality of slits 17a and the hole 18. .
[0029]
In the fourth embodiment, as shown in FIG. 5, the angle formed by a line connecting both ends of the permanent magnet 16 constituting each rotor magnetic pole and the center of the rotating shaft 19 is an electrical angle about the magnetic pole axis. It is formed in the range of 115 to 120 degrees. This can be applied to all of the first to third embodiments.
[0030]
Also in the fourth embodiment, a high torque can be obtained without increasing the induced voltage at a high rotation speed. In particular, by setting the angle formed between both ends of the magnetic pole formed by the permanent magnet 16 and the center of the rotating shaft 19 in an electric angle of 115 to 120 degrees around the magnetic pole axis, the saliency on the axis between the magnetic poles increases. A larger reluctance torque can be generated.
[0031]
In the fifth embodiment, non-magnetic stainless steel is used for any one or all of the slit 17 of the first embodiment, the hole 18 of the second embodiment, the slit 17 and the hole 18 of the third embodiment. Is embedded. By adopting such a configuration, it is needless to say that the effects of each of the above-described embodiments can be obtained, and the mechanical strength is improved by embedding the non-magnetic stainless steel in the slit 17 or the hole 18.
[0032]
In the sixth embodiment, any one or all of the slits 17 of the first embodiment, the holes 18 of the second embodiment, the slits 17 and the holes 18 of the third embodiment are electrically nonconductive. A magnetic material such as copper or aluminum is embedded therein. According to the sixth embodiment, it goes without saying that the effect of each of the above-described embodiments can be obtained. Rotate.
[0033]
【The invention's effect】
According to the present invention, an excessive induced voltage at a high rotation speed can be suppressed, a large reluctance torque can be obtained, and the volume and the number of parts of the permanent magnet, the number of processes are not increased, and the rotation direction is increased. It is possible to provide a permanent magnet type rotating electric machine capable of increasing the total torque without any restrictions such as the above.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a first embodiment of a permanent magnet type rotating electric machine according to the present invention.
FIG. 2 is an enlarged longitudinal sectional view showing only the rotor of FIG. 1;
FIG. 3 is an enlarged longitudinal sectional view showing only a rotor in a second embodiment of the permanent magnet type rotating electric machine of the present invention.
FIG. 4 is an enlarged longitudinal sectional view showing only a rotor in a third embodiment of the permanent magnet type rotating electric machine of the present invention.
FIG. 5 is an enlarged longitudinal sectional view showing only a rotor in a fourth embodiment of the permanent magnet type rotating electric machine of the present invention.
FIG. 6 is a longitudinal sectional view showing an example of a conventional permanent magnet type rotating electric machine.
FIG. 7 is an enlarged longitudinal sectional view showing only the rotor of FIG. 6;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Stator 2 ... Stator core 2a ... Stator winding storage part 3 ... Stator winding 4 ... Rotor 5 ... Rotor core 6 ... Permanent magnet 7 ... Hole 11 ... Stator 12 ... Stator core 12a ... Stator winding storage section 13 Stator winding 14 Rotor 15 Rotor iron core 15a Housing space 16 Permanent magnet 17 Slit 17a Slit 18 Hole 18 Hole 19 Rotation shaft

Claims

円筒状の固定子鉄心の内周面に固定子巻線が配設された固定子と、該固定子の内周側に所定の空隙を介して回転可能に支持された回転子とからなる永久磁石型回転電機において、
前記回転子は、
円柱状の回転子鉄心と、
前記回転子鉄心の軸方向両端面の中心同士を結んだ位置に貫通配設された回転軸と、
前記回転子鉄心の内部に前記回転軸と平行に夫々埋設され、各組は各々軸方向と直交する断面で見たときほぼＶ字状であって、該Ｖ字の角部が前記回転軸側に向くように配設された板状の永久磁石からなる少なくとも２組の回転子磁極と、
前記回転子鉄心に設けられ、前記各回転子磁極に沿うように前記回転子磁極の外周面側にほぼＶ字状に形成された磁気抵抗形成部と、
を具備した永久磁石型回転電機。A stator comprising a stator in which a stator winding is disposed on the inner peripheral surface of a cylindrical stator core, and a rotor rotatably supported on the inner peripheral side of the stator via a predetermined gap. In a magnet type rotating electric machine,
The rotor,
A cylindrical rotor core,
A rotary shaft penetratingly disposed at a position connecting centers of both axial end surfaces of the rotor core,
Each set is embedded in the rotor core in parallel with the rotating shaft, and each set is substantially V-shaped when viewed in a cross section orthogonal to the axial direction, and a corner of the V-shape is located on the rotating shaft side. At least two pairs of rotor magnetic poles each comprising a plate-shaped permanent magnet disposed so as to face
A magnetic resistance forming portion provided on the rotor core and formed substantially in a V shape on the outer peripheral surface side of the rotor magnetic pole along the rotor magnetic poles;
A permanent magnet type rotating electric machine equipped with:

前記磁気抵抗形成部は、スリット、該スリットに非磁性材料を充填したもの、複数の穴、該各穴に非磁性材料を充填したもの、穴とスリットを組み合わせたもの、穴とスリットに夫々非磁性材料を充填したもののいずれかで構成したものである請求項１記載の永久磁石型回転電機。The magnetic resistance forming portion includes a slit, a non-magnetic material filled in the slit, a plurality of holes, a non-magnetic material filled in each of the holes, a combination of the hole and the slit, and a non-magnetic material in each of the hole and the slit. 2. The permanent magnet type rotating electric machine according to claim 1, wherein the permanent magnet type rotating electric machine is made of one of magnetic materials.

円筒状の固定子鉄心の内周面に固定子巻線が配設された固定子と、該固定子の内周側に所定の空隙を介して回転可能に支持された回転子とからなる永久磁石型回転電機において、
前記回転子は、
円柱状の回転子鉄心と、
前記回転子鉄心の軸方向両端面の中心同士を結んだ位置に貫通配設された回転軸と、
前記回転子鉄心の内部に前記回転軸と平行に夫々埋設され、各組は各々軸方向と直交する断面で見たときほぼＶ字状であって、該Ｖ字の角部が前記回転軸側に向くように配設された板状の永久磁石からなる少なくとも２組の回転子磁極と、
前記回転子鉄心に設けられ、前記各回転子磁極に沿うように前記回転子磁極の外周面側にほぼＶ字状に形成された複数のスリット又は複数の穴と、
を具備した永久磁石型回転電機。A stator comprising a stator in which a stator winding is disposed on the inner peripheral surface of a cylindrical stator core, and a rotor rotatably supported on the inner peripheral side of the stator via a predetermined gap. In a magnet type rotating electric machine,
The rotor,
A cylindrical rotor core,
A rotary shaft penetratingly disposed at a position connecting centers of both axial end surfaces of the rotor core,
Each set is embedded in the rotor core in parallel with the rotating shaft, and each set is substantially V-shaped when viewed in a cross section orthogonal to the axial direction, and a corner of the V-shape is located on the rotating shaft side. At least two pairs of rotor magnetic poles each comprising a plate-shaped permanent magnet disposed so as to face
A plurality of slits or a plurality of holes formed in the rotor core and formed substantially in a V-shape on the outer peripheral surface side of the rotor magnetic pole along the respective rotor magnetic poles;
A permanent magnet type rotating electric machine equipped with:

円筒状の固定子鉄心の内周面に固定子巻線が配設された固定子と、該固定子の内周側に所定の空隙を介して回転可能に支持された回転子とからなる永久磁石型回転電機において、
前記回転子は、
円柱状の回転子鉄心と、
前記回転子鉄心の軸方向両端面の中心同士を結んだ位置に貫通配設された回転軸と、
前記回転子鉄心の内部に前記回転軸と平行に夫々埋設され、各組は各々軸方向と直交する断面で見たときほぼＶ字状であって、該Ｖ字の角部が前記回転軸側に向くように配設された板状の永久磁石からなる少なくとも２組の回転子磁極と、
前記回転子磁極の各組に対して複数設けられ、その回転子磁極の該Ｖ字の角部と前記回転軸とを結ぶ磁極軸に対称に形成される各々内部を空隙とした孔と、
を具備した永久磁石型回転電機。A stator comprising a stator in which a stator winding is disposed on the inner peripheral surface of a cylindrical stator core, and a rotor rotatably supported on the inner peripheral side of the stator via a predetermined gap. In a magnet type rotating electric machine,
The rotor,
A cylindrical rotor core,
A rotary shaft penetratingly disposed at a position connecting centers of both axial end surfaces of the rotor core,
Each set is embedded in the rotor core in parallel with the rotating shaft, and each set is substantially V-shaped when viewed in a cross section orthogonal to the axial direction, and a corner of the V-shape is located on the rotating shaft side. At least two pairs of rotor magnetic poles each comprising a plate-shaped permanent magnet disposed so as to face
A plurality of holes each having an internal space formed symmetrically to a magnetic pole axis connecting the corner of the V-shape of the rotor magnetic pole and the rotation axis are provided for each set of the rotor magnetic poles,
A permanent magnet type rotating electric machine equipped with:

前記永久磁石が形成する磁極の両端部と回転軸中心とがなす角度が、磁極軸を中心に電気角１１５〜１２０度の範囲にあることを特徴とする請求項３〜４のいずれかに記載の永久磁石型回転電機。The angle formed between both ends of the magnetic pole formed by the permanent magnet and the center of the rotation axis is within a range of an electrical angle of 115 to 120 degrees around the magnetic pole axis. Permanent magnet type rotating electric machine.

前記スリットあるいは孔に非磁性材を充填してなることを特徴とする請求項３〜４のいずれかに記載の永久磁石型回転電機。The permanent magnet type rotating electric machine according to any one of claims 3 to 4, wherein the slit or the hole is filled with a non-magnetic material.

前記スリットあるいは孔には導電性の非磁性材を充填してなることを特徴とする請求項３〜４のいずれかに記載の永久磁石型回転電機。The permanent magnet type rotating electric machine according to any one of claims 3 to 4, wherein the slit or the hole is filled with a conductive non-magnetic material.