JP3817416B2 - Permanent magnet rotating electric machine and electric vehicle using the same - Google Patents

Description

【００３３】
と定義する。この式は、誘起電圧波形が正弦波であれば、電機角９０度における電圧は実効値の√２倍であることに基づいたものである。すなわちこの値が１より大きい場合は凸波形、１より小さい場合は凹波形であり、１に近いほど正弦波に近いということになる。
【００３４】
このグラフからも、θが２６度および３４度付近において、誘起電圧波形が正弦波に近似することがわかる。
【００３５】
ところで、この角度をスロットピッチτｓ＝７.５度のｎ＋０.５倍（ｎは自然数）である２６.２５度，３３.７５度と比較すると、図３，図４、および図５において少なくとも誤差±１度の範囲内にて一致している。
【００３６】
すなわち、θ（度）が
θ≒(ｎ＋０.５)×τｓ （ｎは自然数）
で表される値のとき、誘起電圧の波形が正弦波に近似する。
【００３７】
さらに図６にθを変化させた場合の誘起電圧のピーク値と実効値を示す。
【００３８】
図６において実効値はθが大きくなるに従って増加している。これはθが大きくなれば永久磁石が大きくなり、当然に主磁束も大きくなることが原因である。
【００３９】
一方ピーク値は、θが大きくなるに従って階段状の変化を示していることがわかる。すなわちθが２６度よりも小さいときはθが増加するに従って僅かながら下降し、２６度を越えると急激に上昇している。さらに約３２度を頂点としてまた緩やかに下降していることがわかる。
【００４０】
一般的に実効値が大きいほど主磁束は大きくなり、駆動トルクをより多く得ることができる。一方ピーク値は、制御回路等はその永久磁石回転電機特有の実効値に合わせて設計されることから、できるだけ実効値の√２倍に近い方がよい。
【００４１】
従ってθは、図６においてピーク値が実効値の√２倍に近く、しかも実効値が大きいという観点から、２６度付近が最も優れていると考えられる。
【００４２】
次に、θを２６度に固定しながらφを変化させ、磁束量の補正を行うことで主磁束によるトルクとリラクタンストルクの和が最大となる角度φを求める。
【００４３】
回転電機の駆動トルクＴは、永久磁石による磁束をψ，ｑ軸インダクタンスをＬｑ，ｄ軸インダクタンスをＬｄ，ｑ軸巻線電流をＩｑ，ｄ軸巻線電流をＩｄとすると、
Ｔ＝ψＩｑ＋(Ｌｑ−Ｌｄ)Ｉｑ×Ｉｄ
で表される。
【００４４】
この式において右辺の第１項は永久磁石の主磁束によるトルクであり、第２項は隣り合った永久磁石間の回転子部材、すなわち補助突極によるリラクタンストルクである。これら二つの値は、それぞれ永久磁石，補助突極がなす回転子の周方向の角度に依存することから、駆動トルクを最大とする永久磁石の周方向の角度は個々の回転子において一義的に定まる。
【００４５】
図７にφと（モータの使用頻度を考慮した）加重平均効率（インバータ損失含む）の関係を示す。図からφは３６度が最も大きいことがわかる。
【００４６】
従って、本実施形態の場合、θが２６度でφが３６度の永久磁石を用いれば、誘起電圧の波形が正弦波に近似し、誘起電圧のピーク値を抑えながら、かつ最大の駆動トルクを得ることができる永久磁石回転電機の設計が可能である。
【００４７】
さらに、上記のθとφの角度による永久磁石の形状の汎用性を確認するため、半径や積厚，出力などが異なる回転電機について検討した磁束密度分布を図８に、誘起電圧波形を図９に、φと加重平均効率（インバータ損失含む）の関係を図１０に示す。この実施形態においても、図９よりθが２６度のとき誘起電圧波形が正弦波に近く、図１０よりφが３６度のとき駆動トルクが最大になることがわかる。
【００４８】
さらに上記θは、通常よく用いられる固定子ティース部がなす角αと固定子スロット部がなす角βがほぼ等しい場合にはスロットピッチτｓのｎ＋０.５ 倍 （ｎは自然数）の場合が優れているが、αとβが大きく異なる場合には、ｎを自然数として、
θ≒ｎ×τｓ＋α
または
θ≒ｎ×τｓ＋β
とした方が誘起電圧波形は正弦波に近くなる。特に後者がより正弦波に近い。
【００４９】
さらに、固定子スロット部をなす角βと固定子開口部をなす角γが大きく異なる場合、すなわちティースの突起が大きい場合には、
θ≒ｎ×τｓ＋γ
とした方が誘起電圧波形は正弦波に近くなる。
【００５０】
ここで突起部の径方向長さが小さい場合、突起部の磁束が飽和し、γがほとんどθに影響しなくなる。そこでγがθに対して影響する度合いを係数Ａ（０＜Ａ≦１）
とすると、
θ≒ｎ×τｓ＋γ×Ａ
と表わすことができる。
【００５１】
また、永久磁石８はネオジウム磁石以外でもよく、たとえば図５の波形狂い率の検討をフェライト磁石で行った場合を図１１に示す。
【００５２】
ネオジウム磁石を用いて検討した図５と比較するとθが機械角で２度ほど小さくなっているが、この理由はフェライト磁石がネオジウム磁石と比べて磁石の強さが約１／３のため、固定子スロットの突起部を十分に飽和できないからである。よって、フェライト磁石を用いた場合、誘起電圧波形を正弦波に近似させるθは
θ≒ｎ×τｓ＋γ （ｎは自然数）
となる。
【００５３】
なお、本発明において、誘起電圧波形を正弦波に近似させる角度θは磁石形状によらない。図１２に他の実施形態として磁石形状が長方形の場合の磁束密度分布を、図１３に図１２の実施形態における誘起電圧波形を、図１４に他の実施形態として磁石形状がアーク形の場合の磁束密度分布を、図１５に図１４における誘起電圧波形を、図１６に他の実施形態として磁石形状が円弧状の台形の場合の磁束密度分布を、図１７に図１６における誘起電圧波形を、図１８に他の実施形態として磁石形状がＶ字形の場合の磁束密度分布を、図１９に図１８における誘起電圧波形を、図２０に他の実施形態として磁石形状がＵ字形の場合の磁束密度分布を、図２１に図２０における誘起電圧波形を示す。いずれの場合も図のようなθ＝２６度で誘起電圧波形が正弦波に近似していることがわかる。
【００５４】
一方、永久磁石が回転子内に一部埋め込まれている場合は、永久磁石部と鉄部の磁束の疎密が大きくなるため、
θ≒ｎ×τｓ＋γ （ｎは自然数）
の場合が誘起電圧波形を正弦波に近似できる。この場合θは、永久磁石８が回転子鉄心７の表面に露出している部分が回転子周方向になす角度となる。
【００５５】
図２２に本発明の他の実施形態として磁石形状がアーク形で一部埋め込まれている場合の磁束密度分布を、図２３に図２２における誘起電圧波形を、図２４に他の実施形態として磁石形状が円弧状の台形で一部埋め込まれている場合の磁束密度分布を、図２５に図２４における誘起電圧波形を、図２６に他の実施形態として磁石形状が概略台形で一部埋め込まれている場合の磁束密度分布を、図２７に図２６における誘起電圧波形を示す。いずれの場合も図のようなθ＝２４度で誘起電圧波形を正弦波に近似できることがわかる。
【００５６】
また、誘起電圧のピーク値を抑えながら、コギングトルクや騒音を低減するためには、磁石の両端に図２８のような磁気的な空隙を設けることが有効である。ここで磁気的な空隙とは、物体が存在しない空間としてもよいし、非磁性体の物質を挿入または充填し、ワニスや接着剤などで固定したものでもよい。
【００５７】
さらに、本発明による永久磁石回転電機は、電動車両の駆動モータとして用いた場合に有効である。
【００５８】
永久磁石回転電機を駆動モータとして用いた電動車両のブレーキ動作時、または降坂時には、回転電機が発電機として動作し、制御回路に誘起電圧が発生する。通常、制御回路は回転電機の誘起電圧の実効値に合わせて設計されているので、波形のピーク値によって誘起電圧が実効値の√２倍を大きく超過しないよう、本発明のように誘起電圧の波形を正弦波に近似させ、ピーク値を抑えることによって、より安全性の高い電動車両を得ることができる。
【００５９】
なお本発明は、永久磁石の個数（極数）は８極以外でもよく、固定子のスロット数も４８個以外でもよい。さらに永久磁石８はネオジウム磁石以外でもよく、永久磁石を構成する角度は製作誤差の範囲内である幅を持つことは言うまでもない。また、波形改善が有効となるものは、内転型，外転型などの回転電機に限らず、リニアモータなどにも応用できる。
【００６０】
【発明の効果】
本発明によれば、誘起電圧の波形が正弦波に近似していることにより、誘起電圧のピーク値を実効値に対して抑えることができる。
【００６１】
また本発明によれば、誘起電圧の波形が正弦波に近似するように、前記永久磁石の固定子側の面の周方向長さを設定したことにより、誘起電圧のピーク値を抑えながら、大きな駆動トルクを得ることができる。
【００６２】
また本発明によれば、誘起電圧の波形を正弦波に近似させることにより、車両のブレーキング時または降坂時に永久磁石回転電機が発生する誘起電圧のピーク値を抑え、より安全な電動車両を得ることができる。
【図面の簡単な説明】
【図１】本発明の一実施形態をなす永久磁石回転電機の周方向断面図の一部を示す。
【図２】図１の磁束密度分布図を示す。
【図３】図１のθを２４，２６，２８度とした場合の最高回転数における誘起電圧波形を示す。
【図４】図１のθを３２，３４，３６度とした場合の最高回転数における誘起電圧波形を示す。
【図５】図１のθと波形狂い率の関係図を示す。
【図６】図１のθと誘起電圧ピーク値および実効値の関係図を示す。
【図７】図１のφと（モータの使用頻度を考慮した）加重平均効率（インバータ損失含む）の関係図を示す。
【図８】図１のθとφを、半径や積厚，出力などが異なる他の実施形態に適用した場合の磁束密度分布図を示す。
【図９】図８における誘起電圧波形を示す。
【図１０】図８におけるφと加重平均効率（インバータ損失を含む）の関係図を示す。
【図１１】フェライト磁石を用いた本発明の他の実施形態をなす永久磁石回転電機のθと波形狂い率の関係図を示す。
【図１２】本発明の他の実施形態をなす永久磁石回転電機の磁束密度分布図を示す。
【図１３】図１２の誘起電圧波形を示す。
【図１４】本発明の他の実施形態をなす永久磁石回転電機の磁束密度分布図を示す。
【図１５】図１４の誘起電圧波形を示す。
【図１６】本発明の他の実施形態をなす永久磁石回転電機の磁束密度分布図を示す。
【図１７】図１６の誘起電圧波形を示す。
【図１８】本発明の他の実施形態をなす永久磁石回転電機の磁束密度分布図を示す。
【図１９】図１８の誘起電圧波形を示す。
【図２０】本発明の他の実施形態をなす永久磁石回転電機の磁束密度分布図を示す。
【図２１】図２０の誘起電圧波形を示す。
【図２２】本発明の他の実施形態をなす永久磁石回転電機の磁束密度分布図を示す。
【図２３】図２２の誘起電圧波形を示す。
【図２４】本発明の他の実施形態をなす永久磁石回転電機の磁束密度分布図を示す。
【図２５】図２４の誘起電圧波形を示す。
【図２６】本発明の他の実施形態をなす永久磁石回転電機の磁束密度分布図を示す。
【図２７】図２６の誘起電圧波形を示す。
【図２８】本発明の他の実施形態をなす永久磁石回転電機の周方向断面図を示す。
【符号の説明】
１…固定子、２…固定子鉄心、３…スロット、４…開口部、５…回転空隙、６…回転子、７…回転子鉄心、８ａ，８ｂ…永久磁石、９…回転軸、１０…空隙。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a permanent magnet rotating electric machine and an electric vehicle, and more particularly to a permanent magnet rotating electric machine configured by arranging and fixing a plurality of permanent magnets in a circumferential direction of a rotor.
[0002]
[Prior art]
Conventionally, as one type of rotating electrical machine, a permanent magnet rotating electrical machine using a permanent magnet as a magnetic field generating means of a rotor has been used.
[0003]
As a conventional permanent magnet rotating electric machine, a permanent magnet rotating electric machine using a permanent magnet embedded rotor is described in Japanese Patent Application Laid-Open No. 5-76146 as an attempt to increase torque and efficiency.
[0004]
This publication discloses a stator in which three-phase stator windings are arranged in a plurality of slots formed in an annular stator core. Further, as the rotor, a plurality of storage portions extending in the axial direction are formed on the inner peripheral portion of the substantially circular rotor core fitted and fixed to the rotation shaft, and a permanent magnet having a rectangular cross section is formed in the storage portion. A configuration is disclosed in which arbitrary adjacent permanent magnets are inserted so as to generate magnetic fluxes having opposite polarities toward the rotor surface. In addition, the rotor is rotatably disposed in an annular stator in a state having an inner peripheral portion of the stator core and a predetermined rotation gap.
[0005]
A rotating electric machine using a rectangular permanent magnet as described above is more efficient because the field weakening is more effective during high-speed rotation. Therefore, it is effective for a device that requires high-speed rotation in nature, such as a drive motor for an electric vehicle.
[0006]
[Problems to be solved by the invention]
However, the conventional permanent magnet rotating electric machine as described above has the following problems with respect to the induced voltage waveform.
[0007]
When the rotor is rotated by an external force, an induced voltage is generated in the rotating electrical machine, and a current flows through the energization circuit or the control circuit. Therefore, in order to protect the control circuit more safely, the control circuit is designed so that the effective value of the induced voltage at a predetermined rotational speed is measured in advance and can withstand or suppress the value.
[0008]
However, the actual induced voltage appears in the form of several waveforms superimposed on a sine wave. Since the effective value is an average value of the waveform, there is always a peak value exceeding √2 times the effective value. Therefore, in order to more reliably protect the control circuit designed to support √2 times the effective value, it is necessary to bring the peak value closer to √2 times the effective value.
[0009]
In order to lower the peak value, it is conceivable to reduce the amount of magnetic flux generated by the permanent magnet itself. However, if the amount of magnetic flux is reduced, naturally the driving torque when the rotating electric machine is operated as an electric motor is also lowered.
[0010]
In view of the above circumstances, an object of the present invention is to suppress the peak value of the induced voltage with respect to the effective value without reducing the driving torque in the permanent magnet rotating electrical machine.
[0011]
Another object of the present invention is to provide a safer electric vehicle by suppressing the peak value of the induced voltage generated by the permanent magnet rotating electric machine when the vehicle is braked or downhill.
[0012]
[Means for Solving the Problems]
Here, the present invention provides a permanent magnet rotating electrical machine and an electric vehicle that are embedded in the rotor core and that are adjacent to each other in the circumferential direction so that their polarities are opposite to each other. The plurality of permanent magnets constituting the plurality of magnetic poles are arranged in the circumferential direction of the stator side surface so that the waveform of the induced voltage generated by the rotation of the rotor approximates a sine wave. it characterized in that a length is set.
[0013]
Further, according to the present invention, in the permanent magnet rotating electric machine and the electric vehicle, the permanent magnet in each of the plurality of magnetic poles of the rotor is arranged so that the waveform of the induced voltage generated by the rotation of the rotor approximates a sine wave. it characterized in that the length between the circumferential ends of the side a and the auxiliary salient pole side is set.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a permanent magnet rotating electrical machine according to an embodiment of the present invention will be described with reference to the drawings.
[0016]
FIG. 1 is a circumferential sectional view of an embodiment in which the present invention is applied to a three-phase 8-pole, 48-slot inner rotor type permanent magnet rotating electric machine, and the figure shows one of the pole pairs. FIG. 2 is a magnetic flux density distribution diagram of FIG.
[0017]
The permanent magnet rotating electric machine includes a stator 1 and a rotor 6, and the rotor 6 is rotatably disposed in the stator 1 with a rotation gap 5 (gap) as shown in the figure.
[0018]
The stator 1 includes a U-phase stator winding U1, a V-phase stator winding V1, and a W-phase stator winding W1 in 48 slots 3 formed in a substantially annular stator core 2. Is inserted and arranged. Openings 4 are formed in the inner peripheral portion of the stator core corresponding to the slots.
[0019]
On the other hand, the rotor 6 has a rotor core 7 fitted and fixed to the rotary shaft 9, and eight permanent magnets 8 (8a and 8b in the figure) made of neodymium are inserted and fixed to the rotor core 7 in the axial direction. A storage part is formed. As shown in the figure, the permanent magnets 8 are arranged so that adjacent ones have opposite polarities, and the rotor core 7 is configured by laminating a plurality of silicon steel plates.
[0020]
At this time, as the permanent magnet 8, in the circumferential cross section, an angle formed by the side on the stator side, that is, the outer peripheral surface width, is θ, and the side on the anti-stator side, that is, the inner peripheral surface width, is the axis. A shape having a shape such that θ is smaller than φ where φ is φ is used.
[0021]
It should be noted that θ and φ can be defined similarly when the permanent magnet 8 is not in the trapezoidal shape as shown in FIG. For example, in the case of an arch shape, θ and φ indicate the angle formed by the end point and the other end point of the stator side arch with respect to the axis, and the angle formed by the end point and the other end point of the anti-stator side arch with respect to the axis. .
[0022]
In this case, when the magnitude of θ is changed, the waveform of the induced voltage generated when the rotor is rotated by an external force changes. Further, when the magnitude of φ is changed, φ defines the circumferential maximum width of the permanent magnet 8, and thus the magnitude of the driving torque of the rotating electrical machine changes.
[0023]
Here, θ (degrees) can take a value in the range of 0 <θ <45 because the number of poles of the permanent magnet is 8, but when θ is close to 45 degrees, the circumferential width of the auxiliary salient pole Is extremely small, it becomes difficult to obtain reluctance torque. On the other hand, when it is close to 0, the waveform of the induced voltage depends on φ instead of θ, but there is no value of φ that achieves both the realization of the ideal waveform described later and the maximization of the driving torque at the same time. .
[0024]
Therefore, when θ is sampled, the induced voltage waveforms at the maximum rotational speed when θ is set to 24, 26, and 28 degrees, and when set to 32, 34, and 36 degrees are as shown in FIGS. 3 and 4, respectively.
[0025]
As can be seen from the diagram, the induced voltage waveform includes a convex waveform in which five peaks are superimposed on a sine wave, a waveform that has relatively little unevenness and approximates a sine wave, and a concave waveform in which five valleys are superimposed. It turns out that it appears with sex.
[0026]
That is, a concave waveform appears when θ is in the range of 18.75 <θ <26.25 and 33.75 <θ <41.25, and θ is in the range of 26.25 <θ <33.75. Sometimes a convex waveform appears. When θ is approximately 26.25 degrees and 33.75 degrees, a waveform that has relatively little unevenness and approximates a sine wave appears.
[0027]
More detailed analysis shows that θ is {(2n−1) +0.5} × τs <θ <(2n + 0.5) × τs, where τs is the slot pitch of the stator and n is a natural number.
A convex waveform appears, and θ is (n + 0.5) × τs.
, The unevenness is reduced, and θ is (2n + 0.5) × τs <θ <{(2n + 1) +0.5} × τs.
It can be seen that a concave waveform appears when within the range of.
[0028]
The peak value of these waveforms is the value of the peak of the convex part with an electrical angle of 90 degrees when it is a convex waveform, and the value of the peak of two convex parts sandwiching the concave part with an electrical angle of 90 degrees when it is a concave waveform. Therefore, the peak value is minimized when a waveform having no irregularities, that is, a waveform approximated to a sine wave appears.
[0029]
In this embodiment, it can be seen from the figure that the induced voltage waveform is closest to the sine wave when θ is about 26 degrees or about 34 degrees.
[0030]
Next, in order to quantitatively evaluate how close the actual induced voltage waveform is to a sine wave, a waveform error rate is defined, and the waveform error rate due to θ is shown as a graph in FIG.
[0031]
Here, the waveform error rate is
[0032]
[Expression 1]

[0033]
It is defined as This equation is based on the fact that if the induced voltage waveform is a sine wave, the voltage at the electrical angle of 90 degrees is √2 times the effective value. That is, when this value is greater than 1, it is a convex waveform, and when it is less than 1, it is a concave waveform.
[0034]
This graph also shows that the induced voltage waveform approximates a sine wave when θ is around 26 and 34 degrees.
[0035]
By the way, when this angle is compared with 26.25 degrees and 33.75 degrees which are n + 0.5 times (n is a natural number) of slot pitch τs = 7.5 degrees, at least an error is found in FIGS. It agrees within the range of ± 1 degree.
[0036]
That is, θ (degree) is θ≈ (n + 0.5) × τs (n is a natural number)
When the value is represented by the following formula, the waveform of the induced voltage approximates a sine wave.
[0037]
Further, FIG. 6 shows the peak value and effective value of the induced voltage when θ is changed.
[0038]
In FIG. 6, the effective value increases as θ increases. This is because the permanent magnet increases as θ increases, and the main magnetic flux naturally increases.
[0039]
On the other hand, it can be seen that the peak value shows a step-like change as θ increases. That is, when θ is smaller than 26 degrees, it decreases slightly as θ increases, and when it exceeds 26 degrees, it increases rapidly. Furthermore, it turns out that it descends gently again at about 32 degrees.
[0040]
In general, the larger the effective value, the larger the main magnetic flux, and the more driving torque can be obtained. On the other hand, the peak value is preferably as close to √2 times the effective value as possible because the control circuit and the like are designed according to the effective value unique to the permanent magnet rotating electrical machine.
[0041]
Therefore, it is considered that θ is most excellent around 26 degrees from the viewpoint that the peak value is close to √2 times the effective value and the effective value is large in FIG.
[0042]
Next, φ is changed while θ is fixed at 26 degrees, and the amount φ of the magnetic flux is corrected to obtain an angle φ that maximizes the sum of the torque due to the main magnetic flux and the reluctance torque.
[0043]
The driving torque T of the rotating electrical machine is expressed as follows: magnetic flux by a permanent magnet is ψ, q-axis inductance is Lq, d-axis inductance is Ld, q-axis winding current is Iq, and d-axis winding current is Id.
T = ψIq + (Lq−Ld) Iq × Id
It is represented by
[0044]
In this equation, the first term on the right side is the torque due to the main magnetic flux of the permanent magnet, and the second term is the reluctance torque due to the rotor member between adjacent permanent magnets, that is, the auxiliary salient poles. Since these two values depend on the circumferential angle of the rotor formed by the permanent magnet and the auxiliary salient pole, respectively, the circumferential angle of the permanent magnet that maximizes the driving torque is uniquely determined for each rotor. Determined.
[0045]
FIG. 7 shows the relationship between φ and the weighted average efficiency (including inverter loss) (considering the motor usage frequency). It can be seen from the figure that φ is the largest at 36 degrees.
[0046]
Therefore, in the case of the present embodiment, if a permanent magnet having θ of 26 degrees and φ of 36 degrees is used, the waveform of the induced voltage approximates a sine wave, and the maximum driving torque is reduced while suppressing the peak value of the induced voltage. Design of a permanent magnet rotating electrical machine that can be obtained is possible.
[0047]
Furthermore, in order to confirm the versatility of the shape of the permanent magnet according to the angles of θ and φ described above, FIG. 8 shows a magnetic flux density distribution and FIG. 9 shows an induced voltage waveform obtained by examining rotating electric machines having different radii, stack thicknesses, and outputs. FIG. 10 shows the relationship between φ and the weighted average efficiency (including inverter loss). Also in this embodiment, it can be seen from FIG. 9 that the induced voltage waveform is close to a sine wave when θ is 26 degrees, and from FIG. 10 that the driving torque is maximized when φ is 36 degrees.
[0048]
Furthermore, when the angle α formed by the commonly used stator tooth portion and the angle β formed by the stator slot portion are substantially equal, the above θ is excellent when the slot pitch τs is n + 0.5 times (n is a natural number). However, when α and β are greatly different, n is a natural number,
θ ≒ n × τs + α
Or θ≈n × τs + β
The induced voltage waveform becomes closer to a sine wave. In particular, the latter is closer to a sine wave.
[0049]
Furthermore, when the angle β forming the stator slot and the angle γ forming the stator opening are greatly different, that is, when the teeth protrusion is large,
θ ≒ n × τs + γ
The induced voltage waveform becomes closer to a sine wave.
[0050]
Here, when the radial length of the protrusion is small, the magnetic flux of the protrusion is saturated, and γ hardly affects θ. Therefore, the degree of influence of γ on θ is expressed by coefficient A (0 <A ≦ 1)
Then,
θ≈n × τs + γ × A
Can be expressed as
[0051]
Further, the permanent magnet 8 may be other than a neodymium magnet. For example, FIG. 11 shows a case where the waveform deviation rate in FIG.
[0052]
Compared with Fig. 5 studied using a neodymium magnet, θ is about 2 degrees smaller in mechanical angle. This is because the strength of the ferrite magnet is about 1/3 that of the neodymium magnet. This is because the protrusion of the child slot cannot be sufficiently saturated. Therefore, when a ferrite magnet is used, θ that approximates the induced voltage waveform to a sine wave is θ≈n × τs + γ (n is a natural number)
It becomes.
[0053]
In the present invention, the angle θ that approximates the induced voltage waveform to a sine wave does not depend on the magnet shape. FIG. 12 shows the magnetic flux density distribution when the magnet shape is a rectangle as another embodiment, FIG. 13 shows the induced voltage waveform in the embodiment of FIG. 12, and FIG. 14 shows the case where the magnet shape is an arc shape as another embodiment. FIG. 15 shows the induced voltage waveform in FIG. 14, FIG. 16 shows the magnetic flux density distribution in the case of a trapezoid having a circular arc as another embodiment, FIG. 17 shows the induced voltage waveform in FIG. 18 shows the magnetic flux density distribution when the magnet shape is V-shaped as another embodiment, FIG. 19 shows the induced voltage waveform in FIG. 18, and FIG. 20 shows the magnetic flux density when the magnet shape is U-shaped as another embodiment. The distribution is shown in FIG. 21 and the induced voltage waveform in FIG. In either case, it can be seen that the induced voltage waveform approximates a sine wave at θ = 26 degrees as shown in the figure.
[0054]
On the other hand, when the permanent magnet is partially embedded in the rotor, the density of the magnetic flux between the permanent magnet part and the iron part increases.
θ ≒ n × τs + γ (n is a natural number)
In this case, the induced voltage waveform can be approximated to a sine wave. In this case, θ is an angle formed by a portion where the permanent magnet 8 is exposed on the surface of the rotor core 7 in the circumferential direction of the rotor.
[0055]
FIG. 22 shows the magnetic flux density distribution when the magnet is partially arc-embedded as another embodiment of the present invention, FIG. 23 shows the induced voltage waveform in FIG. 22, and FIG. 24 shows the magnet as another embodiment. The magnetic flux density distribution when the shape is partially embedded in an arcuate trapezoid, FIG. 25 shows the induced voltage waveform in FIG. 24, and FIG. 26 shows another embodiment in which the magnet shape is partially trapped in a trapezoidal shape. FIG. 27 shows the induced voltage waveform in FIG. In either case, it can be seen that the induced voltage waveform can be approximated to a sine wave at θ = 24 degrees as shown.
[0056]
In order to reduce the cogging torque and noise while suppressing the peak value of the induced voltage, it is effective to provide magnetic gaps as shown in FIG. 28 at both ends of the magnet. Here, the magnetic gap may be a space where no object is present, or may be a non-magnetic substance inserted or filled and fixed with a varnish or an adhesive.
[0057]
Furthermore, the permanent magnet rotating electrical machine according to the present invention is effective when used as a drive motor for an electric vehicle.
[0058]
During braking operation or downhill of an electric vehicle using a permanent magnet rotating electric machine as a drive motor, the rotating electric machine operates as a generator, and an induced voltage is generated in the control circuit. Normally, the control circuit is designed in accordance with the effective value of the induced voltage of the rotating electrical machine, so that the induced voltage does not greatly exceed √2 times the effective value due to the peak value of the waveform as in the present invention. An electric vehicle with higher safety can be obtained by approximating the waveform to a sine wave and suppressing the peak value.
[0059]
In the present invention, the number of permanent magnets (number of poles) may be other than eight, and the number of stator slots may be other than 48. Furthermore, the permanent magnet 8 may be other than a neodymium magnet, and it goes without saying that the angle constituting the permanent magnet has a width within the range of manufacturing errors. In addition, those in which the waveform improvement is effective can be applied to linear motors and the like as well as rotary electric machines such as an inner rotation type and an outer rotation type.
[0060]
【The invention's effect】
According to the present invention, since the waveform of the induced voltage approximates a sine wave, the peak value of the induced voltage can be suppressed from the effective value.
[0061]
According to the present invention, the circumferential length of the surface of the permanent magnet on the stator side is set so that the waveform of the induced voltage approximates a sine wave. A driving torque can be obtained.
[0062]
In addition, according to the present invention, by approximating the waveform of the induced voltage to a sine wave, the peak value of the induced voltage generated by the permanent magnet rotating electric machine during braking or downhill of the vehicle is suppressed, and a safer electric vehicle can be obtained. Obtainable.
[Brief description of the drawings]
FIG. 1 shows a part of a circumferential sectional view of a permanent magnet rotating electrical machine that constitutes an embodiment of the present invention.
2 shows a magnetic flux density distribution diagram of FIG.
FIG. 3 shows an induced voltage waveform at the maximum number of revolutions when θ in FIG. 1 is 24, 26, and 28 degrees.
4 shows an induced voltage waveform at the maximum number of rotations when θ in FIG. 1 is 32, 34, and 36 degrees.
5 shows a relationship diagram between θ in FIG. 1 and a waveform error rate. FIG.
6 shows a relationship diagram between θ of FIG. 1, an induced voltage peak value, and an effective value. FIG.
FIG. 7 is a graph showing the relationship between φ in FIG. 1 and weighted average efficiency (including inverter loss) (considering the frequency of use of the motor).
FIG. 8 shows a magnetic flux density distribution diagram when θ and φ in FIG. 1 are applied to other embodiments having different radii, stack thicknesses, outputs, and the like.
9 shows an induced voltage waveform in FIG.
10 shows a relationship diagram between φ in FIG. 8 and weighted average efficiency (including inverter loss).
FIG. 11 is a diagram showing the relationship between θ and the waveform error rate of a permanent magnet rotating electrical machine that uses another ferrite magnet according to another embodiment of the present invention.
FIG. 12 is a magnetic flux density distribution diagram of a permanent magnet rotating electric machine that constitutes another embodiment of the present invention.
13 shows the induced voltage waveform of FIG.
FIG. 14 is a magnetic flux density distribution diagram of a permanent magnet rotating electric machine that constitutes another embodiment of the present invention.
15 shows the induced voltage waveform of FIG.
FIG. 16 shows a magnetic flux density distribution diagram of a permanent magnet rotating electric machine that constitutes another embodiment of the present invention.
17 shows the induced voltage waveform of FIG.
FIG. 18 is a magnetic flux density distribution diagram of a permanent magnet rotating electric machine that constitutes another embodiment of the present invention.
FIG. 19 shows the induced voltage waveform of FIG.
FIG. 20 is a magnetic flux density distribution diagram of a permanent magnet rotating electric machine that constitutes another embodiment of the present invention.
21 shows the induced voltage waveform of FIG.
FIG. 22 is a magnetic flux density distribution diagram of a permanent magnet rotating electric machine that constitutes another embodiment of the present invention.
FIG. 23 shows the induced voltage waveform of FIG.
FIG. 24 is a magnetic flux density distribution diagram of a permanent magnet rotating electric machine that constitutes another embodiment of the present invention.
25 shows the induced voltage waveform of FIG.
FIG. 26 is a magnetic flux density distribution diagram of a permanent magnet rotating electric machine that constitutes another embodiment of the present invention.
FIG. 27 shows an induced voltage waveform of FIG.
FIG. 28 is a circumferential cross-sectional view of a permanent magnet rotating electric machine that constitutes another embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Stator, 2 ... Stator iron core, 3 ... Slot, 4 ... Opening part, 5 ... Rotation space | gap, 6 ... Rotor, 7 ... Rotor iron core, 8a, 8b ... Permanent magnet, 9 ... Rotating shaft, 10 ... Voids.

Claims (24)

A stator,
A rotor arranged rotatably on the stator via a gap;
The stator is
A stator core formed with a plurality of slots ;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase ;
The rotor is
The rotor core,
A plurality of magnetic poles that are embedded in the rotor core and that are adjacent to each other in the circumferential direction are arranged circumferentially with respect to the rotor core so as to form a plurality of magnetic poles. Ri you and a permanent magnet,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
Between the permanent magnets of the rotor core, Ri Contact is formed auxiliary salient pole for generating a reluctance torque,
Wherein the plurality of permanent magnets, are respectively the waveform of the induced voltage generated by rotation of the rotor so as to approximate to a sine wave, the length in the circumferential direction of the side surface of the stator is set A permanent magnet rotating electrical machine. A stator,
A rotor arranged rotatably on the stator via a gap;
The stator is
A stator core formed with a plurality of slots ;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase ;
The rotor is
The rotor core,
A plurality of magnetic poles that are embedded in the rotor core and that are adjacent to each other in the circumferential direction are arranged circumferentially with respect to the rotor core so as to form a plurality of magnetic poles. Ri you and a permanent magnet,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
Between the permanent magnets of the rotor core, Ri Contact is formed auxiliary salient pole for generating a reluctance torque,
When the pitch of the slot and .tau.s (degrees), and the angular width in the circumferential direction of the side surface of the stator of the permanent magnet with respect to the axis of the rotor and theta (degrees),
θ≈ (n + 0.5) × τs (n is a natural number)
A permanent magnet rotating electric machine characterized by the above. A stator,
A rotor arranged rotatably on the stator via a gap;
The stator is
A stator core formed with a plurality of slots ;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase ;
The rotor is
The rotor core,
A plurality of magnetic poles that are embedded in the rotor core and that are adjacent to each other in the circumferential direction are arranged circumferentially with respect to the rotor core so as to form a plurality of magnetic poles. Ri you and a permanent magnet,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
Between the permanent magnets of the rotor core, Ri Contact is formed auxiliary salient pole for generating a reluctance torque,
The pitch of the slot and .tau.s (degrees), the angle at which the circumferential width of the side surface of the stator of the permanent magnet with respect to the axis of the rotor and theta (degrees), the teeth in the stator The angle that the section forms with respect to the rotor axis is α (degrees), the angle that the slot forms with respect to the rotor axis is β (degrees), and the opening of the slot is the axis of the rotor When the angle formed with respect to is γ (degrees),
θ ≒ n × τs + α (n is a natural number)
Or θ ≒ n × τs + β (n is a natural number)
Or θ ≒ n × τs + γ (n is a natural number)
A permanent magnet rotating electric machine characterized by being one of the following. A stator,
A rotor arranged rotatably on the stator via a gap;
The stator is
A stator core formed with a plurality of slots ;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase ;
The rotor is
The rotor core,
A plurality of magnetic poles that are embedded in the rotor core and that are adjacent to each other in the circumferential direction are arranged circumferentially with respect to the rotor core so as to form a plurality of magnetic poles. Ri you and a permanent magnet,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
Between the permanent magnets of the rotor core, Ri Contact is formed auxiliary salient pole for generating a reluctance torque,
The number of slots is 48;
The number of the permanent magnets is 8,
The permanent magnet rotating electric machine, wherein the width of the circumferential direction of the side surface of the stator of the permanent magnet the angle formed with respect to the axis of the rotor is within the range of 26 ± 1 °. In the permanent magnet rotating electric machine according to any one of claims 1 to 4,
A permanent magnet rotating electrical machine, wherein magnetic gaps are formed at both ends of the permanent magnet. In the permanent magnet rotating electric machine according to any one of claims 1 to 4,
The permanent magnet rotating electric machine is characterized in that a cross-sectional shape of the permanent magnet is any one of a rectangular shape, a trapezoidal shape, an arch shape, an arc shape, a V shape, and a U shape. A permanent magnet rotating electrical machine,
A vehicle equipped with a control circuit for controlling the permanent magnet rotating electric machine ,
The permanent magnet rotating electric machine is
It outputs the sum of the torque from the magnet and the reluctance torque,
A stator,
Have a rotor that is rotatably disposed with a gap to the stator,
The stator is
A stator core formed with a plurality of slots ;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase ;
The rotor is
The rotor core,
For outputting torque by the magnet , the rotor core is circumferentially arranged so that the ones embedded in the rotor core and adjacent in the circumferential direction have opposite polarities. disposed Jo, Ri Contact and a plurality of permanent magnets that constitute a plurality of magnetic poles,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
Wherein Between the permanent magnets of the rotor core, Ri auxiliary salient poles are formed contact for generating the reluctance torque,
Wherein the plurality of permanent magnets, respectively are, as the waveform of the induced voltage generated by rotation of the rotor is approximated to a sine wave, the length in the circumferential direction of the surface on the side of the stator is set ,
Wherein the control circuit, at the time of or during downhill vehicles brakes, electric vehicle, characterized in that the current due to the induced voltage generated in the permanent magnet rotating electric machine by the rotation of the rotor flow. A permanent magnet rotating electrical machine,
A vehicle equipped with a control circuit for controlling the permanent magnet rotating electric machine ,
The permanent magnet rotating electric machine is
It outputs the sum of the torque from the magnet and the reluctance torque,
A stator,
Have a rotor that is rotatably disposed with a gap to the stator,
The stator is
A stator core formed with a plurality of slots ;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase ;
The rotor is
The rotor core,
For outputting torque by the magnet , the rotor core is circumferentially arranged so that the ones embedded in the rotor core and adjacent in the circumferential direction have opposite polarities. disposed Jo, Ri Contact and a plurality of permanent magnets that constitute a plurality of magnetic poles,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
Wherein Between the permanent magnets of the rotor core, Ri auxiliary salient poles are formed contact for generating the reluctance torque,
When the pitch of the slot and .tau.s (degrees), and the angular width in the circumferential direction of the side surface of the stator of the permanent magnet with respect to the axis of the rotor and theta (degrees),
θ≈ (n + 0.5) × τs (n is a natural number)
And
Wherein the control circuit, at the time of or during downhill vehicles brakes, electric vehicle, characterized in that the current due to the induced voltage generated in the permanent magnet rotating electric machine by the rotation of the rotor flow. A permanent magnet rotating electrical machine,
A vehicle equipped with a control circuit for controlling the permanent magnet rotating electric machine ,
The permanent magnet rotating electric machine is
It outputs the sum of the torque from the magnet and the reluctance torque,
A stator,
Have a rotor that is rotatably disposed with a gap to the stator,
The stator is
A stator core formed with a plurality of slots ;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase ;
The rotor is
The rotor core,
For outputting torque by the magnet , the rotor core is circumferentially arranged so that the ones embedded in the rotor core and adjacent in the circumferential direction have opposite polarities. disposed Jo, Ri Contact and a plurality of permanent magnets that constitute a plurality of magnetic poles,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
Wherein Between the permanent magnets of the rotor core, Ri auxiliary salient poles are formed contact for generating the reluctance torque,
And τs pitch of said slot (degrees), the angle at which the circumferential width of the side surface of the stator of the permanent magnet with respect to the axis of the rotor and theta (degrees), the teeth in the stator The angle that the section forms with respect to the rotor axis is α (degrees), the angle that the slot forms with respect to the rotor axis is β (degrees), and the opening of the slot is the axis of the rotor When the angle formed with respect to is γ (degrees),
θ ≒ n × τs + α (n is a natural number)
Or θ ≒ n × τs + β (n is a natural number)
Or θ ≒ n × τs + γ (n is a natural number)
Either
Wherein the control circuit, at the time of or during downhill vehicles brakes, electric vehicle, characterized in that the current due to the induced voltage generated in the permanent magnet rotating electric machine by the rotation of the rotor flow. A permanent magnet rotating electrical machine,
A vehicle equipped with a control circuit for controlling the permanent magnet rotating electric machine ,
The permanent magnet rotating electric machine is
It outputs the sum of the torque from the magnet and the reluctance torque,
A stator,
Have a rotor that is rotatably disposed with a gap to the stator,
The stator is
A stator core formed with a plurality of slots ;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase ;
The rotor is
The rotor core,
For outputting torque by the magnet , the rotor core is circumferentially arranged so that the ones embedded in the rotor core and adjacent in the circumferential direction have opposite polarities. disposed Jo, Ri Contact and a plurality of permanent magnets that constitute a plurality of magnetic poles,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
Wherein Between the permanent magnets of the rotor core, Ri auxiliary salient poles are formed contact for generating the reluctance torque,
The number of slots is 48;
The number of the permanent magnets is 8,
The angle at which the circumferential width with respect to the axis of the rotor on the side surface of the stator of the permanent magnet is in the range of 26 ± 1 °,
Wherein the control circuit, at the time of or during downhill vehicles brakes, electric vehicle, characterized in that the current due to the induced voltage generated in the permanent magnet rotating electric machine by the rotation of the rotor flow. The electric vehicle according to any one of claims 7 to 10,
An electric vehicle characterized in that magnetic gaps are formed at both ends of the permanent magnet. The electric vehicle according to any one of claims 7 to 10,
A cross-sectional shape of the permanent magnet is any one of a rectangular shape, a trapezoidal shape, an arch shape, an arc shape, a V shape, and a U shape. A stator,
A rotor arranged rotatably on the stator via a gap;
The stator is
A stator core formed with a plurality of slots;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase;
The rotor is
The rotor core,
A plurality of permanent magnets embedded in the rotor core and arranged circumferentially with respect to the rotor core;
A plurality of auxiliary salient poles for generating reluctance torque are formed inside the rotor core,
The plurality of permanent magnets are:
Constituting a plurality of magnetic poles of the rotor,
Provided with respect to the rotor core so that those adjacent to each other in the circumferential direction across the auxiliary salient pole have opposite polarities,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
The permanent magnet in each of the plurality of magnetic poles has a circumferential end on the stator side and the auxiliary salient pole side so that a waveform of an induced voltage generated by rotation of the rotor approximates a sine wave. A permanent magnet rotating electrical machine characterized in that the length between the parts is set. A stator,
A rotor arranged rotatably on the stator via a gap;
The stator is
A stator core formed with a plurality of slots;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase;
The rotor is
The rotor core,
A plurality of permanent magnets embedded in the rotor core and arranged circumferentially with respect to the rotor core;
A plurality of auxiliary salient poles for generating reluctance torque are formed inside the rotor core,
The plurality of permanent magnets are:
Constituting a plurality of magnetic poles of the rotor,
Provided with respect to the rotor core so that those adjacent to each other in the circumferential direction across the auxiliary salient pole have opposite polarities,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
The slot pitch is τs (degrees), and the width between circumferential ends of the plurality of magnetic poles on the stator side of the permanent magnet and on the auxiliary salient pole side is the axis of the rotor. When the angle made with respect to θ is (degrees),
θ≈ (n + 0.5) × τs (n is a natural number)
A permanent magnet rotating electric machine characterized by the above. A stator,
A rotor arranged rotatably on the stator via a gap;
The stator is
A stator core formed with a plurality of slots;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase;
The rotor is
The rotor core,
A plurality of permanent magnets embedded in the rotor core and arranged circumferentially with respect to the rotor core;
A plurality of auxiliary salient poles for generating reluctance torque are formed inside the rotor core,
The plurality of permanent magnets are:
Constituting a plurality of magnetic poles of the rotor,
Provided with respect to the rotor core so that those adjacent to each other in the circumferential direction across the auxiliary salient pole have opposite polarities,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
The slot pitch is τs (degrees), and the width between circumferential ends of the plurality of magnetic poles on the stator side of the permanent magnet and on the auxiliary salient pole side is the axis of the rotor. The angle formed with respect to the rotor is θ (degrees), the angle formed by the teeth of the stator with respect to the rotor axis is α (degrees), and the angle between the slot and the rotor axis is β. (Degrees), and when the angle formed by the opening of the slot with respect to the axis of the rotor is γ (degrees),
θ ≒ n × τs + α (n is a natural number)
Or θ ≒ n × τs + β (n is a natural number)
Or θ ≒ n × τs + γ (n is a natural number)
A permanent magnet rotating electric machine characterized by being one of the following. A stator,
A rotor arranged rotatably on the stator via a gap;
The stator is
A stator core formed with a plurality of slots;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase;
The rotor is
The rotor core,
A plurality of permanent magnets embedded in the rotor core and arranged circumferentially with respect to the rotor core;
A plurality of auxiliary salient poles for generating reluctance torque are formed inside the rotor core,
The plurality of permanent magnets are:
Constituting a plurality of magnetic poles of the rotor,
Provided with respect to the rotor core so that those adjacent to each other in the circumferential direction across the auxiliary salient pole have opposite polarities,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
The number of slots is 48;
The number of the magnetic poles is 8,
An angle formed by a width between circumferential ends of the permanent magnets on the stator side and the auxiliary salient pole side of each of the plurality of magnetic poles with respect to the axis of the rotor is in a range of 26 ± 1 degree. A permanent magnet rotating electrical machine characterized by being in the interior. The permanent magnet rotating electric machine according to any one of claims 13 to 16,
A permanent magnet rotating electrical machine, wherein a magnetic gap is formed at a circumferential end of each of the magnetic poles on the auxiliary salient pole side of the permanent magnet. The permanent magnet rotating electric machine according to any one of claims 13 to 16,
The permanent magnet rotating electric machine is characterized in that a cross-sectional shape of the permanent magnet is any one of a rectangular shape, a trapezoidal shape, an arch shape, an arc shape, a V shape, and a U shape. A permanent magnet rotating electrical machine,
A vehicle equipped with a control circuit for controlling the permanent magnet rotating electric machine,
The permanent magnet rotating electric machine is
It outputs the sum of the torque from the magnet and the reluctance torque,
A stator,
A rotor arranged rotatably on the stator via a gap;
The stator is
A stator core formed with a plurality of slots;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase;
The rotor is
The rotor core,
For generating torque by the magnet, comprising a plurality of permanent magnets embedded in the rotor core and arranged circumferentially with respect to the rotor core;
A plurality of auxiliary salient poles for generating the reluctance torque are formed inside the rotor core,
The plurality of permanent magnets are:
Constituting a plurality of magnetic poles of the rotor,
Provided with respect to the rotor core so that those adjacent to each other in the circumferential direction across the auxiliary salient pole have opposite polarities,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
The permanent magnet in each of the plurality of magnetic poles has a circumferential end on the stator side and the auxiliary salient pole side so that a waveform of an induced voltage generated by rotation of the rotor approximates a sine wave. The length between the parts is set,
An electric vehicle characterized in that the control circuit causes a current due to an induced voltage generated in the permanent magnet rotating electric machine to flow due to rotation of the rotor when the vehicle is braked or downhill. A permanent magnet rotating electrical machine,
A vehicle equipped with a control circuit for controlling the permanent magnet rotating electric machine,
The permanent magnet rotating electric machine is
It outputs the sum of the torque from the magnet and the reluctance torque,
A stator,
A rotor arranged rotatably on the stator via a gap;
The stator is
A stator core formed with a plurality of slots;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase;
The rotor is
The rotor core,
For generating torque by the magnet, comprising a plurality of permanent magnets embedded in the rotor core and arranged circumferentially with respect to the rotor core;
A plurality of auxiliary salient poles for generating the reluctance torque are formed inside the rotor core,
The plurality of permanent magnets are:
Constituting a plurality of magnetic poles of the rotor,
Provided with respect to the rotor core so that those adjacent to each other in the circumferential direction across the auxiliary salient pole have opposite polarities,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
The slot pitch is τs (degrees), and the width between circumferential ends of the plurality of magnetic poles on the stator side of the permanent magnet and on the auxiliary salient pole side is the axis of the rotor. When the angle made with respect to θ is (degrees),
θ≈ (n + 0.5) × τs (n is a natural number)
And
An electric vehicle characterized in that the control circuit causes a current due to an induced voltage generated in the permanent magnet rotating electric machine to flow due to rotation of the rotor when the vehicle is braked or downhill. A permanent magnet rotating electrical machine,
A vehicle equipped with a control circuit for controlling the permanent magnet rotating electric machine,
The permanent magnet rotating electric machine is
It outputs the sum of the torque from the magnet and the reluctance torque,
A stator,
A rotor arranged rotatably on the stator via a gap;
The stator is
A stator core formed with a plurality of slots;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase;
The rotor is
The rotor core,
For generating torque by the magnet, comprising a plurality of permanent magnets embedded in the rotor core and arranged circumferentially with respect to the rotor core;
A plurality of auxiliary salient poles for generating the reluctance torque are formed inside the rotor core,
The plurality of permanent magnets are:
Constituting a plurality of magnetic poles of the rotor,
Provided with respect to the rotor core so that those adjacent to each other in the circumferential direction across the auxiliary salient pole have opposite polarities,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
The slot pitch is τs (degrees), and the width between circumferential ends of the plurality of magnetic poles on the stator side of the permanent magnet and on the auxiliary salient pole side is the axis of the rotor. The angle formed with respect to the rotor is θ (degrees), the angle formed by the teeth of the stator with respect to the rotor axis is α (degrees), and the angle between the slot and the rotor axis is β. (Degrees), and when the angle formed by the opening of the slot with respect to the axis of the rotor is γ (degrees),
θ ≒ n × τs + α (n is a natural number)
Or θ ≒ n × τs + β (n is a natural number)
Or θ ≒ n × τs + γ (n is a natural number)
Either
An electric vehicle characterized in that the control circuit causes a current due to an induced voltage generated in the permanent magnet rotating electric machine to flow due to rotation of the rotor when the vehicle is braked or downhill. A permanent magnet rotating electrical machine,
A vehicle equipped with a control circuit for controlling the permanent magnet rotating electric machine,
The permanent magnet rotating electric machine is
It outputs the sum of the torque from the magnet and the reluctance torque,
A stator,
A rotor arranged rotatably on the stator via a gap;
The stator is
A stator core formed with a plurality of slots;
A stator winding housed in the plurality of slots and configured of three phases of a U phase, a V phase, and a W phase;
The rotor is
The rotor core,
For generating torque by the magnet, comprising a plurality of permanent magnets embedded in the rotor core and arranged circumferentially with respect to the rotor core;
A plurality of auxiliary salient poles for generating the reluctance torque are formed inside the rotor core,
The plurality of permanent magnets are:
Constituting a plurality of magnetic poles of the rotor,
Provided with respect to the rotor core so that those adjacent to each other in the circumferential direction across the auxiliary salient pole have opposite polarities,
The slots corresponding to the U-phase, V-phase, and W-phase of the stator winding are arranged so as to face the magnetic poles, respectively.
The number of slots is 48;
The number of the magnetic poles is 8,
An angle formed by a width between circumferential ends of the permanent magnets on the stator side and the auxiliary salient pole side of each of the plurality of magnetic poles with respect to the axis of the rotor is in a range of 26 ± 1 degree. In
An electric vehicle characterized in that the control circuit causes a current due to an induced voltage generated in the permanent magnet rotating electric machine to flow due to rotation of the rotor when the vehicle is braked or downhill. The electric vehicle according to any one of claims 19 to 22,
An electric vehicle characterized in that a magnetic gap is formed at a circumferential end of each of the magnetic poles on the auxiliary salient pole side of the permanent magnet. The electric vehicle according to any one of claims 19 to 22,
A cross-sectional shape of the permanent magnet is any one of a rectangular shape, a trapezoidal shape, an arch shape, an arc shape, a V shape, and a U shape.

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