CN101442245A - Self-wind cooled rotor low torque ripple magneto resistance genus motor - Google Patents

Abstract

The invention relates to a low-torque ripple reluctance motor with a self air-cooled rotor, and belongs to a reluctance motor. The motor comprises a rotor and a stator, a salient-pole tooth of the rotor is an oblique tooth in a structural shape of an axial-flow fan blade and is decided by an air intake angle, an air outlet angle and rotor length, and the structure of a salient-pole tooth of the stator keeps electrical property of the motor consistent with the prior double-salient-pole motor with an oblique rotor tooth. When the rotor of the motor rotates, the salient-pole tooth of the rotor generates an air suction force to introduce the air inside the motor to be exhausted by an air outlet, so as to take away heat of the rotor of the motor and achieve the aim of self air cooling. The low-torque ripple reluctance motor is suitable for the reluctance motors with various structures, which comprise a double-salient-pole motor, a switched reluctance motor, an inductor motor, and the like. The low-torque ripple reluctance motor can automatically dissipate heat of the rotor of the reluctance motor, reduce volume and weight of the motor, and optimize the size of the motor.

Description

Self-wind cooled rotor low torque ripple magneto resistance genus motor

Technical field

The present invention is a kind of self-wind cooled rotor low torque ripple magneto resistance genus motor, comprises switched reluctance machines, double salient-pole electric machine, inductor machine etc., belongs to technical field of motors.

Background technology

Magnetic resistance class motor is the conversion that realizes electromechanical energy by the variation of magnetic resistance.Such motor mainly comprises switched reluctance machines, double salient-pole electric machine, inductor machine etc.With the double salient-pole electric machine is example, and rotor adopts punching silicon-steel to be overrided to form, and salient-pole structure is arranged on the rotor, no winding, and brushless, thereby this type motor has simple in structure, reliable outstanding advantage, is particularly suitable for high-speed cruising.In addition, electric excitation biconvex electrode electric machine also has the relatively low advantage of its exciting power, so double salient-pole electric machine has wide practical use in the dynamical system and the power-supply system of every field such as Aero-Space, naval vessel, green energy resource.

But also there is the higher relatively shortcoming of torque pulsation in such motor, has a strong impact on normal operation when rotating speed is low.Studies show that and to reduce torque pulsation by adopting rotor helical teeth structure that be called traditional rotor helical teeth magnetic resistance class motor at this, this structure can not provide from the air cooling function.Simultaneously, because such motor is conversion, the especially double salient-pole electric machine of realizing electromechanical energy by the variation of magnetic resistance, the magnetic flux of its stator, rotor all is an alternation, so there is tangible eddy current loss in it, and efficient is relatively low, and stator, rotor temperature rise are obvious.Gently so then can influence life of winding, heavy then can damage winding.Usual way is to reduce winding current density to choose, reduce magnetic conductor work magnetic flux density and choose, increase method such as outside area of dissipation and reduce temperature rise, but this can increase the volume weight of motor, causes waste.This has just limited the range of application of such motor, especially the application of large-power occasions.

Summary of the invention

The present invention is on the basis of traditional rotor helical teeth magnetic resistance class motor, utilize the design feature of rotor with salient pole tooth, propose a kind of have axial flow blower blade structure shape from air cooling function rotor, can effectively loose and remove the novel magnetic resistance class motor of rotor heat, low torque ripple.The rotor with salient pole tooth root of this motor makes it to have from the air cooling function according to the design of axial flow blower planform, and the stator salient poles tooth root makes it to produce the function that reduces torque pulsation according to the design of rotor with salient pole odontoid.

Utilize the present invention can when design of electrical motor, improve winding current density and choose, improve magnetic conductor work magnetic flux density and choose, reduce outside area of dissipation, reduce to greatest extent motor volume weight, optimize the size of motor, save resource, reduce consuming.Be particularly suitable for the slow-speed of revolution, powerful application scenario.

Self-wind cooled rotor low torque ripple magneto resistance genus motor of the present invention, comprise switched reluctance machines, double salient-pole electric machine, inductor machine etc., be applicable to the 6n/4n utmost point or the 8n/6n utmost point or 10n/8n electrode structure, n is a positive integer, or other various basic structures, what so-called herein various structure titles were described is the number of salient pole tooth on stator and the rotor, for example: so-called 6/4 utmost point is meant that stator has 6 salient pole teeth, rotor has 4 salient pole teeth, or the like; Be applicable to various excitation modes simultaneously, comprise electric excitation, permanent magnet excitation and composite excitation and various working method, comprise electronic work and generating work; Be applicable to various helical teeth structures simultaneously.

With 6/4 electrode structure double salient-pole electric machine is example.The design of the magnetic resistance class motor of other structure is identical therewith, different only be that the number of salient pole tooth on rotor and the stator is different.

This invention motor is except having axial flow blower blade structure shape from air cooling function rotor, on (other) electrical property, be consistent with conventional rotors helical teeth structure biconvex pole electromotor, from each cross section of motor cross section all is consistent, and consistent with the cross section of conventional rotors helical teeth structure biconvex pole electromotor.

But the salient pole tooth of this invention rotor is the inclined teeth of axial flow blower blade structure shape: the rotor with salient pole tooth press the axial flow blower flabellum rotate in air-breathing principle design, with rotor with salient pole tooth depth center and rotor center axis apart from r ₂(mean value of rotor outer radius and rotor inside radius) is radius, is the face of cylinder that the center work equates with rotor length with the rotor center axis, and this face of cylinder and salient pole flank form the space intersection.This face of cylinder is launched to become the plane, space intersection generate flat circle arcuation curve, inside and outside two flat circle arcuation curves are formed circular-arc blade, have so promptly constituted plane cascade.Circular-arc blade center circle camber line is called for short mean camber line, and the angle between its air inlet place tangent line and the rotor center parallel axes line is called the air inlet angle beta, and the angle between its gas outlet place's tangent line and the rotor center parallel axes line is called the gas outlet angle [alpha] ₂Described circular-arc curve is by entrance angle β and exit angle α ₂And the rotor length decision, $\mathrm{\β}={\tan }^{-1}\frac{C}{U},$ ${\mathrm{\α}}_2={\tan }^{-1}\frac{C}{U-C_{2u}},$ $C_{2u}=\frac{L_u}{U},$ C in the formula is the air inlet absolute velocity, and U is a rim speed, L _uBe the wheel rim merit.

When rotor rotation, salient pole produces the suction force to gas, gas is introduced motor internal discharged by outlet.In the motor inlet end velocity triangle of plane cascade and correspondence, according to the cooling gas flow requirement, determine air inlet absolute velocity C, calculate rim speed U according to tachometer, determine relative velocity direction α by velocity triangle.Make rotor with salient pole blade inlet angle β=α, avoid air inlet to produce separation losses.Circular-arc mean camber line blade outlet angle α ₂To determine that length is determined according to rotor length through pneumatic design.

On the air inlet salient pole, install a radome fairing additional, reduce intake resistance.

In order to keep motor (other) electrical property consistent with traditional rotor helical teeth double salient-pole electric machine, be example with the oblique tooth of traditional rotor, other helical teeth mode is consistent therewith: the rotor with salient pole flank is with rotor outer radius r ₁For forming curve L on the cylinder tangent plane plane outspread drawing of radius _A, the width of expanded view is 2 π r ₁The stator salient poles flank is with stator inside radius r ₄For forming curve L on the cylinder tangent plane plane outspread drawing of radius _B, the width of expanded view is 2 π r ₄, this expanded view to be dwindled, reduced width is to 2 π r ₁, points all on the then former expanded view all change the curve L on the former expanded view in proportion _BBecome the curve L that dwindles on the expanded view _CCurve L _AWith curve L _CMeet: with curve L _AWith curve L _CThe end points on the left side coincides together to converge and make a horizontal line, the lateral vertical of this horizontal line and expanded view on a figure and at this some place.Cross curve L _AOn every bit can make this horizontal vertical line, this vertical line and curve L _A, curve L _CTwo intersection points that intersect form one-to-one relationship, with curve L _AOn every bit to the distance on expanded view base with its at curve L _COn corresponding points subtract each other to the distance on base, obtain difference, make a point with this difference for arriving horizontal distance, these all points are coupled together form a curve, this curve is a straight line, with the rotor tooth side of traditional rotor helical teeth structure biconvex pole electromotor be that the curve that forms on the cylinder tangent plane plane outspread drawing of radius is in full accord with the rotor outer radius.

Satisfying under the above-mentioned condition, can accomplish optimization to design of electrical motor, both can as often as possible take away the heat that rotor produces, can accomplish again owing to the energy that air flows is lost reaches minimum; Electric machine structure is changed little, unobvious its complexity that increases simultaneously.

Description of drawings

Fig. 1: 6/4 electrode structure is from air cooling rotor double salient-pole electric machine rotor structure schematic diagram

Fig. 2: 6/4 electrode structure is from air cooling rotor double salient-pole electric machine rotor structure schematic diagram

Fig. 3: 6/4 electrode structure is from air cooling rotor double salient-pole electric machine stator structure schematic diagram

Fig. 4: rotor is with salient pole tooth depth centre-height r ₂(mean value of rotor outer radius and rotor inside radius) is the cylindrical section plane outspread drawing of radius

Fig. 5: motor inlet end velocity triangle schematic diagram

Fig. 6: radius r beyond the rotor ₁Cylinder tangent plane plane outspread drawing for radius

Fig. 7: stator is with inside radius r ₄Cylinder tangent plane plane outspread drawing for radius

Fig. 8: stator is with inside radius r ₄Being reduced into width for the cylinder tangent plane plane outspread drawing of radius is 2 π r ₁Dwindle figure

Fig. 9: curve L _A, L _CBetween concern schematic diagram

Number in the figure and symbol description: 1, double salient-pole electric machine rotor; 2, rotor with salient pole tooth; 3, rotor center axis; 4, rotor outer radius r ₁5, rotor inside radius r ₃6, rotor with salient pole tooth depth centre-height r ₂(mean value of rotor outer radius and rotor inside radius); 7, with rotor with salient pole tooth depth centre-height r ₂The face of cylinder for radius; 8, with rotor outer radius r ₁The face of cylinder for radius; 9, stator inside radius r ₄10, with stator inside radius r ₄The face of cylinder for radius; 11, the space intersection of the face of cylinder 7 and salient pole flank formation; 12, space intersection 11 is at the plane curve that launches on the plane; 13, the air inlet angle beta of circular-arc mean camber line 20; 14, air inlet absolute velocity C; 15, rim speed U; 16, relative velocity direction α; 17, relative velocity W; 18, the rotor with salient pole flank is with rotor outer radius r ₁The curve L that forms on the cylinder tangent plane plane outspread drawing for radius _A19, the stator salient poles flank is with stator inside radius r ₄The curve L that forms on the cylinder tangent plane plane outspread drawing for radius _B20, circular-arc mean camber line; 21, circular-arc mean camber line air inlet place tangent line; 22, rotor center installing hole; 23, rotor location notch; 24, double salient-pole electric machine stator; 25, stator center axis; 26, radome fairing cross section; 27, stator location notch; 28, place, circular-arc mean camber line gas outlet tangent line; 29, rotor center parallel axes line; 30, the gas outlet angle [alpha] of circular-arc mean camber line 20 ₂31, rotor center parallel axes line; 32, L _BThe curve L that shortens into _C33, horizontal line; 34, L _AWith L _CThe straight line that forms to the difference of the distance on base of corresponding points.

Specific embodiments

With the double salient-pole electric machine is example, owing to have only salient pole tooth and teeth groove on the rotor of double salient-pole electric machine, there is not winding, the present invention proposes to utilize salient pole tooth and this design feature of teeth groove, double salient-pole electric machine rotor with salient pole tooth is designed to the blade structure shape of axial flow blower, can aspirate rotor one end (inlet end) ambient air when making rotor rotation and enter the rotor teeth groove, go out from the rotor other end (outlet side) again, thereby directly take away the heat cooling motor that rotor produces.In order to reach this purpose, can design the shape of rotor with salient pole tooth according to the operation principle of axial flow blower flabellum.

Fig. 1 and Fig. 2 are that 6/4 electrode structure is from air cooling rotor double salient-pole electric machine rotor structure schematic diagram, Fig. 3 is that 6/4 electrode structure is from air cooling rotor double salient-pole electric machine stator structure schematic diagram, label title among the figure: 1, double salient-pole electric machine rotor, 2, rotor with salient pole tooth, 3, rotor center axis, 4, rotor outer radius r ₁, 5, rotor inside radius r ₃, 6, rotor with salient pole tooth depth centre-height r ₂(mean value of rotor outer radius and rotor inside radius), 7, with salient pole tooth depth centre-height r ₂Be the face of cylinder of radius, 8, with rotor outer radius r ₁Be the face of cylinder of radius, 11, the space intersection that forms of the face of cylinder 7 and salient pole flank, 18, the rotor with salient pole flank is with rotor outer radius r ₁The curve L that forms on the cylinder tangent plane plane outspread drawing for radius _A, 22, the rotor center installing hole, 23, the rotor location notch, 9, stator inside radius r ₄, 10, with stator inside radius r ₄Be the face of cylinder of radius, 24, the double salient-pole electric machine stator, 25, the stator center axis, 27, the stator location notch.Wherein salient pole tooth 2 tilts, the inclination situation meets: Fig. 4 is the plane graph that the face of cylinder shown in Figure 27 is launched into, and the flat circle arcuation curve 12 among Fig. 4 is circular curves that the face of cylinder 7 and rotor with salient pole flank form the planar development of space intersection 11 among Fig. 2.Inside and outside two flat circle arcuation curves constitute flat circle arcuation blade, the air inlet place tangent line 21 of the center circular curve 20 of flat circle arcuation blade and the angle between the rotor center parallel axes line 29 are air inlet angle beta 13, and gas outlet place's tangent line 28 of the center circular curve 20 of flat circle arcuation blade and the angle between the rotor center parallel axes line 31 are the bicker α that gives vent to anger ₂30, the label 26 among the figure is the radome fairing cross section.Fig. 5 is a motor inlet end velocity triangle schematic diagram, the label title among the figure: 14, air inlet absolute velocity C, 15, rim speed U, 16, relative velocity direction α, 17, relative velocity W; Fig. 6 is with rotor outer radius r among Fig. 2 ₁Plane outspread drawing for the cylinder tangent plane 8 of radius.Label 18 among the figure is rotor with salient pole flanks with rotor outer radius r ₁The curve L that forms on the cylinder tangent plane plane outspread drawing for radius _A, Fig. 7 is with stator inside radius r among Fig. 3 ₄Be the plane outspread drawing of the cylinder tangent plane 10 of radius, the label 19 among the figure is stator salient poles flanks with stator inside radius r ₄The curve L that forms on the plane outspread drawing for the cylinder tangent plane 10 of radius _BThe rotor with salient pole flank is with rotor outer radius r ₁For the width of the cylinder tangent plane plane outspread drawing of radius is 2 π r ₁The stator salient poles flank is with stator inside radius r ₄For the width of the cylinder tangent plane plane outspread drawing of radius is 2 π r ₄, this expanded view is dwindled, Fig. 8 is that stator is with inside radius r ₄Being reduced into width for the cylinder tangent plane plane outspread drawing of radius is 2 π r ₁Dwindle figure, the label 32 among the figure is L _BThe curve L that shortens into _CL _AWith L _CMeet: Fig. 9 is curve L _A, L _CBetween concern schematic diagram, with L _AAnd L _CThe end points on the left side coincides together and converges on a figure, and makes a horizontal line, the lateral vertical of this horizontal line and expanded view at this some place.Cross L _AOn every bit can make this horizontal vertical line, this vertical line and L _A, L _CTwo intersection points that intersect form one-to-one relationship, with L _AOn every bit to the distance on expanded view base with its at L _COn corresponding points subtract each other to the distance on base, obtain difference,, these all points are coupled together form a curve for making a point with this difference to horizontal distance, this curve is a straight line.Label among the figure: 18, the rotor with salient pole flank is with rotor outer radius r ₁The curve L that forms on the cylinder tangent plane plane outspread drawing for radius _A, 32, L _BThe curve L that shortens into _C33, horizontal line; 34, L _AWith L _CThe straight line that forms to the difference of the distance on base of corresponding points.

The present invention is applicable to the magnetic resistance class motor of various structures.Carrying out energy converting between mechanical calculating, identical when loss is calculated, please refer to the design of electrical motor handbook for such motor with the traditional calculations process.Only provide the design and calculation method of rotor cooling at this.

At first determine the loss P of rotor according to the design of electrical motor handbook.Determine cooling gas flow Q according to this loss then:

$Q=\frac{P}{c_a\·{\mathrm{\Δ\τ}}_a}---\left(1\right)$

Wherein, c _aBe the air ratio thermal capacitance, Δ τ _aFor air by the temperature rise behind the motor.

In the motor inlet end velocity triangle of plane cascade and correspondence, as shown in Figure 5,, determine air inlet absolute velocity C14 by formula (2) according to the requirement of the cooling gas flow Q that determines by formula (1).

$C=\frac{Q}{\mathrm{\ρ}\·A}---\left(2\right)$

Wherein, ρ is a charge air flow density, and A is long-pending for the inlet end cross section of fluid channel.

According to rotating speed, calculate rim speed U15 by (3) formula.

U＝r ₂·ω (3)

Wherein, r ₂Be rotor with salient pole tooth depth centre-height (mean value of rotor outer radius and rotor inside radius) that ω is a rotor angular speed.Determine relative velocity direction α 16 by velocity triangle again, that is:

$\mathrm{\α}={\tan }^{-1}\frac{C}{U}---\left(4\right)$

Make rotor with salient pole blade inlet angle β=α, avoid air inlet to produce separation losses.

Determine wheel rim merit L according to the kinetic energy increment that is produced _u,

That is: $L_u=\frac{1}{2}{\mathrm{\ρC}}^2---\left(5\right)$

Further by L _u=UC _2u: $C_{2u}=\frac{L_u}{U}---\left(6\right)$

And: ${\mathrm{\α}}_2={\tan }^{-1}\frac{C}{U-C_{2u}}---\left(7\right)$

Calculate the gas port angle [alpha] ₂

Determined air inlet angle and gas outlet angle,, just determined the shape of circular-arc blade mean camber line in the plane cascade again in conjunction with the length of rotor.According to the length of the shape of circular-arc blade mean camber line and thickness of silicon steel sheet (comprising insulating varnish) and rotor, calculate the deflection angle of every silicon steel sheet of rotor.Calculate the shape of stator salient poles tooth according to the shape of rotor with salient pole tooth, calculate the deflection angle of every silicon steel sheet of stator, when punching out stator, rotor, go out the location notch of every silicon steel sheet simultaneously, stator, rotor pack formula with each sheet silicon steel sheet according to location notch fixedly compaction moulding get final product.

In order to reduce vapour lock, install a radome fairing at the inlet end place additional, radome fairing can be semi-circular, half elliptic, arcuation curve or other smooth curve.

Claims (1)

1, a kind of self-wind cooled rotor low torque ripple magneto resistance genus motor, comprise rotor and stator, it is characterized in that: described rotor with salient pole tooth is the inclined teeth of axial flow blower blade structure shape, concrete shape is: the distance with rotor with salient pole tooth depth center and rotor center axis is a radius, with the rotor center axis is the face of cylinder and the salient pole flank formation space intersection at center, the curve of this intersection generate on the plane graph of this face of cylinder expansion is circular-arc curve, inside and outside two circular-arc curves are formed circular-arc blade, and the center circle camber line of circular-arc blade is by air inlet angle beta and gas outlet angle [alpha] ₂Decision; Described air inlet angle beta is meant: with the rotor center axis is the center, with rotor with salient pole tooth depth center and rotor center axis apart from r ₂Be radius, the face of cylinder (7) that work equates with rotor length, this face of cylinder (7) forms space intersection (11) with the salient pole flank, and this face of cylinder (7) launched to become the plane, then space intersection (11) generate is a flat circle arcuation curve (12), inside and outside two flat circle arcuation curves are formed circular-arc blade, so promptly constituted plane cascade, the air inlet place tangent line (21) of circular-arc blade center circle camber line (20) and the angle between the rotor center parallel axes line (29) are called the air inlet angle beta; Described gas outlet angle [alpha] ₂Be meant: gas outlet place's tangent line (28) of flat circle arcuation blade center circle camber line (20) and the angle between the rotor center parallel axes line (31) are called the gas outlet angle [alpha] ₂The air inlet angle $\mathrm{\β}={\tan }^{-1}\frac{C}{U},$ The gas outlet angle ${\mathrm{\α}}_2={\tan }^{-1}\frac{C}{U-C_{2u}},$ $C_{2u}=\frac{L_u}{U},$ C in the formula is the air inlet absolute velocity, and U is a rim speed, L _uBe the wheel rim merit; The shape of described stator salient poles tooth should keep the motor electrical property consistent with traditional rotor helical teeth double salient-pole electric machine, and the rotor with salient pole flank is with rotor outer radius r ₁For forming curve L on the cylinder tangent plane plane outspread drawing of radius _A, the width of expanded view is 2 π r ₁The stator salient poles flank is with stator inside radius r ₄For forming curve L on the cylinder tangent plane plane outspread drawing of radius _B, the width of expanded view is 2 π r ₄, this expanded view to be dwindled, reduced width is to 2 π r ₁, points all on the then former expanded view all change the curve L on the former expanded view in proportion _BBecome the curve L that dwindles on the expanded view _CCurve L _AWith curve L _CMeet: with curve L _AWith curve L _CThe end points on the left side coincides together to converge and make a horizontal line, the lateral vertical of this horizontal line and expanded view on a figure and at this some place.Cross curve L _AOn every bit can make this horizontal vertical line, this vertical line and curve L _A, curve L _CTwo intersection points that intersect form one-to-one relationship, with curve L _AOn every bit to the distance on expanded view base with its at curve L _COn corresponding points subtract each other to the distance on base, obtain difference, make a point with this difference for arriving horizontal distance, these all points are coupled together form a curve, this curve is a straight line, with the rotor tooth side of traditional rotor helical teeth structure biconvex pole electromotor be that the curve that forms on the cylinder tangent plane plane outspread drawing of radius is in full accord with the rotor outer radius.

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