CN103529387B - A kind of magneto stall method of testing and system - Google Patents

Abstract

The embodiment of the present invention provides a kind of magneto stall method of testing and system, said method comprising the steps of: determine the Space current vector on stall position; Selected limit phase; Calculate the offset angle between Space current vector and limit phase on stall position; Revise Space current vector according to described offset angle, Space current vector and the limit are coincided, the current phasor of limit phase equals limiting current vector; When the current phasor of limit phase equals limiting current vector, the stall carrying out testing magneto heats up.

Description

A kind of magneto stall method of testing and system

Technical field

The present invention relates to technical field of motors, particularly a kind of magneto stall method of testing and system.

Background technology

The stall of motor, refers to the failure condition of still output torque when rotor rotating speed is 0 turn.Time in stall situation, power factor is extremely low, so the electric current of motor internal can rise to the several times of rated current, and can at short notice by burn-down of electric motor.Therefore, stall test is a big event in the generality test of motor.

The content of stall test is exactly the warming law of testing of electric motors in stall situation.But for magneto, owing to there is three-phase current vector (any two alternate angles are 120 °) in magneto, stall position difference then three-phase current vector is also different, and then the ramp case of stall can change along with the change of stall position, is difficult to unified mensuration and measurement.

Summary of the invention

In view of this, the object of the present invention is to provide a kind of magneto stall method of testing and system, by calculating the limit stall position of magneto, and carrying out stall test on limit stall position.

For achieving the above object, the present invention has following technical scheme:

A kind of magneto stall method of testing, said method comprising the steps of:

Determine the Space current vector on stall position; Selected limit phase;

Calculate the offset angle between Space current vector and limit phase on stall position; Revise Space current vector according to described offset angle, Space current vector and the limit are coincided, the current phasor of limit phase equals limiting current vector;

When the current phasor of limit phase equals limiting current vector, the stall carrying out testing magneto heats up.

The described selected limit is specially mutually:

Using with Space current vector angle minimum one as limit phase.

The offset angle calculated on stall position between Space current vector and limit phase is specially:

Initial deflection angle θ between computer memory current phasor and prima facies, obtains described offset angle in the geometric relationship by initial deflection angle and three phase coordinates.

Initial deflection angle θ between described computer memory current phasor and prima facies is specially:

According to torque capacity minimum current control algorithm, Space current vector is decomposed into exciting current i _dwith torque current i _q;

Extract initial offset θ ₁, and according to exciting current i _dwith torque current i _qcomputer memory current phasor and exciting current i _dbetween angle theta ₂;

Then θ=θ ₁+ θ ₂.

Described according to exciting current i _dwith torque current i _qcomputer memory current phasor and exciting current i _dbetween angle theta ₂be specially:

According to formula ${\mathrm{\θ}}_2=\arctan \frac{i_q}{i_d}+\frac{\mathrm{\π}}{2}$ Obtain θ ₂.

Carry out correction according to described offset angle to Space current vector to be specially:

Directly initial offset θ is revised by the control program of magneto ₁, Space current vector and the limit are coincided;

Or pass through the control program correction exciting current i of magneto _dwith torque current i _q, Space current vector and the limit are coincided.

Described correction initial offset θ ₁be specially:

By initial offset θ ₁increasing or reducing α, α is the angle of offset angle.

Described correction exciting current i _dwith torque current i _qbe specially:

According to formula $\left(\begin{array}{c}{i}_d^{\′}\\ i_q^{\′}\end{array}\right)=\left(\begin{array}{cc}\cos \mathrm{\α}& -\sin \mathrm{\α}\\ \sin \mathrm{\α}& \cos \mathrm{\α}\end{array}\right)\left(\begin{array}{c}{i}_d\\ i_q\end{array}\right)$ Revise;

Wherein, i _d' be revised exciting current; i _q' be revised torque current; α is the angle of offset angle.

A kind of magneto stall test macro, described system specifically comprises:

Position module, for determining the Space current vector on stall position; Selected limit phase;

Computing module, for calculating the offset angle on stall position between Space current vector and limit phase;

Control module, for revising Space current vector according to described offset angle, Space current vector and the limit are coincided, the current phasor of limit phase equals limiting current vector;

Test module, for when the current phasor of limit phase equals limiting current vector, the stall carrying out testing magneto heats up.

Described position module is selected the limit and is specially mutually:

Using with Space current vector angle minimum one as limit phase.

As seen through the above technical solutions, the beneficial effect that the present invention exists is: achieve the stall test of magneto in limit stall position, obtain stall warming law unified and representative in magneto.

Accompanying drawing explanation

In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, accompanying drawing in the following describes is some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.

Fig. 1 is magneto three phase coordinates schematic diagram;

Fig. 2 is method flow diagram described in the embodiment of the present invention;

Fig. 3 is stall rear space current phasor and three phase coordinates relation schematic diagram;

Fig. 4 is d-q coordinate system and three phase coordinate system relation schematic diagram;

Fig. 5 is system architecture schematic diagram described in the embodiment of the present invention.

Embodiment

For making the object of the embodiment of the present invention, technical scheme and advantage clearly, below in conjunction with the accompanying drawing in the embodiment of the present invention, technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is the present invention's part embodiment, instead of whole embodiments.Based on the embodiment in the present invention, those of ordinary skill in the art, not making the every other embodiment obtained under creative work prerequisite, belong to the scope of protection of the invention.

In the present invention, the test of the stall of magneto is carried out on limit stall position.So-called limit stall position, namely makes in three-phase current vector any one to reach maximum amplitude mutually, i.e. the stall position of a certain current phasor that reaches capacity mutually.In this case, a phase current copper loss of the current phasor that reaches capacity is maximum, and what heat up and burn is fastest; One burn mutually namely mean magneto entirety damage.Carry out stall test by ultimate limit state as seen, be representative for magneto.

According to the feature of magneto itself, limit stall position is exactly the vector of three-phase current vector, i.e. Space current vector and a certain position when coinciding.Current phasor in the phase overlapped with Space current vector equals limiting current vector, also just represents that this burns with the fastest speed.

Suppose that the three-phase of magneto is respectively with u, v, w representative, u phase is prima facies, and namely u phase positive dirction angle is 0 angle, and as shown in Figure 1, electric current is respectively i to three phase coordinate systems _u, i _v, i _w, Space current vector is i _s, concrete principle is as follows:

i _s=i _u+i _v+i _w；

i _u＝i _mcosθ； $i_v=i_m\cos (\mathrm{\θ}-\frac{2\mathrm{\π}}{3});i_w=i_m\cos (\mathrm{\θ}-\frac{4\mathrm{\π}}{3})$

Wherein, i _mfor the maximum amplitude of each phase current; θ is i _srelative to the deflection angle of u phase, the namely deflection angle of rotor on stall position.

Obviously according to trigonometric function principle, θ=0 or π, i.e. i _swhen overlapping with u phase is positive and negative, i _u=i _m, u phase current vector reaches capacity current phasor.In like manner i _swhen overlapping with v phase is positive and negative, i _v=i _m, v phase current vector reaches capacity current phasor; i _swhen overlapping with w phase is positive and negative, i _w=i _m, w phase current vector reaches capacity current phasor.

This rule is the basis for limit stall position being carried out stall test.But in the middle of stall test, cannot realize making the stall of magneto to occur on extreme position accurately; Namely be difficult to the stall position that reaches capacity physically; So the present invention compensates utilizing the control program of magneto and revises by calculating to each phase current vector on stall position, the stall of magneto is made to be equivalent to occur on limit stall position, and then carry out stall test, understand the warming law of fabricating of magneto.

With reference to shown in Fig. 2, be a specific embodiment of the method for the invention, described in the present embodiment, method specifically comprises the following steps:

Step 201, the Space current vector determined on stall position; Selected limit phase.

Coordinate system as shown in Figure 3, now there is stall in magneto, and stall position is physically fixed, accordingly its Space current vector i _sposition is determined.Next one in three-phase must be selected as limit phase, to make i by controlling correction in subsequent step _scoincide mutually with the limit, make the current phasor of limit phase equal limiting current vector.That is, which is previously selected as the limit mutually actually, to be i _scorrection clear and definite reference object is provided.

Any one can be selected in theory as limit phase.But preferred, when the selected limit is identical, also need to make the current component of limiting current vector negative direction minimum as far as possible, to ensure magneto not loss of excitation.So according to geometric relationship, using with Space current vector angle minimum one as limit phase.Selecting v phase with reference to figure 3 is limit phase.

Offset angle in step 202, calculating stall position between Space current vector and limit phase; Revise Space current vector according to described offset angle, Space current vector and the limit are coincided, the current phasor of limit phase equals limiting current vector.

V phase is limit phase, the α angle marked in described offset angle and Fig. 3, i _sonly need revise α can coincide with v, after the two overlaps, based on the principle of magneto, namely v phase current vector equals limiting current vector.

Revise according to following method according to described offset angle to Space current vector described in the present embodiment:

For the correction of Space current vector, be complete, namely based on motor principle of vector control by the control program of magneto in the present embodiment.Simply, Space current vector i _sthat three-phase current Vector modulation obtains, but for the ease of controlling, again can by i _sbe decomposed into two orthogonal current components.The current component for generation of magnetic field respectively, i.e. exciting current i _d; With the current component for generation of torque, i.e. torque current i _q, two orthogonal electric currents can form a d-q rectangular coordinate system.

In prior art, control program is by generating torque instruction control i _d, i _qand other correlation parameters, with indirectly control i _s, thus reach the object controlling magneto Driving Torque.Same by control program and torque instruction control i in the present embodiment _s, make i _scoincide with the limit.

Based on the i in Fig. 3 _s, according to " torque capacity minimum current control algorithm " usual in prior art, from i _sin decomposite the i of optimum allocation _dwith i _q, and according to i _dwith i _qdirection set up rectangular coordinate system, as shown in Figure 4.I _dwith i _qbe assigned as well known in the art, therefore not to repeat here.

Visible with reference to Fig. 4, i _stwo parts are divided into, i.e. θ=θ relative to the deflection angle θ of u phase ₁+ θ ₂;

According to the geometric relationship of three phase coordinates, obviously

Wherein, θ ₁for d axle and the angle of u phase, in the present embodiment, be referred to as initial offset; Directly can obtain θ in a control program ₁value;

Can calculate according to geometric relationship,

Then have $\mathrm{\θ}={\mathrm{\θ}}_1+{\mathrm{\θ}}_2={\mathrm{\θ}}_1+\arctan \frac{i_q}{i_d}+\frac{\mathrm{\π}}{2};\mathrm{\α}=\mathrm{\θ}-\frac{2\mathrm{\π}}{3}={\mathrm{\θ}}_1+\arctan \frac{i_q}{i_d}-\frac{\mathrm{\π}}{6}.$

In this step, following two kinds of concrete correcting modes can be adopted:

One is directly to θ by the control program of magneto ₁revise, d-q rectangular coordinate system can be made in the present embodiment to turn clockwise α angle, make i _scoincide with v.

Another kind of mode is then the control program correction i by magneto _dand i _qthe size of two current components, reverse to i _shave an impact, make i _scoincide with v;

For i _dand i _qcorrection with reference to once formula:

$\left(\begin{array}{c}{i}_d^{\′}\\ i_q^{\′}\end{array}\right)=\left(\begin{array}{cc}\cos \mathrm{\α}& -\sin \mathrm{\α}\\ \sin \mathrm{\α}& \cos \mathrm{\α}\end{array}\right)\left(\begin{array}{c}{i}_d\\ i_q\end{array}\right)$

Wherein i _d' and i _q' be revised exciting current and torque current.

Step 203, when the current phasor of limit phase equals limiting current vector, carry out test magneto stall heat up.

The stall situation of magneto was both determined, follow-up test can refer to stall of the prior art test and carries out.

As seen through the above technical solutions, the beneficial effect that the present embodiment exists is: achieve the stall test of magneto in limit stall position, obtain stall warming law unified and representative in magneto.

Corresponding described method embodiment illustrated in fig. 2, discloses a kind of magneto stall test macro in the present embodiment further.Described system is for realizing the system needed for said method, and the two technical scheme is consistent in essence, and in previous embodiment, associated description is equally applicable to the present embodiment, and described system specifically comprises:

Position module, for determining the Space current vector on stall position; Selected limit phase.

Described position module is selected the limit and is specially mutually: using with Space current vector angle minimum one as limit phase.

Computing module, for calculating the offset angle on stall position between Space current vector and limit phase.

Control module, for revising Space current vector according to described offset angle, Space current vector and the limit are coincided, the current phasor of limit phase equals limiting current vector.

Test module, for when the current phasor of limit phase equals limiting current vector, the stall carrying out testing magneto heats up.

The beneficial effect that system described in the present embodiment exists is: achieve the stall test of magneto in limit stall position, obtain stall warming law unified and representative in magneto.

The above is only the preferred embodiment of the present invention; it should be pointed out that for those skilled in the art, under the premise without departing from the principles of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (7)

1. a magneto stall method of testing, is characterized in that, said method comprising the steps of:

Determine the Space current vector on stall position; Selected limit phase;

Calculate the offset angle between Space current vector and limit phase on stall position; Revise Space current vector according to described offset angle, Space current vector and the limit are coincided, the current phasor of limit phase equals limiting current vector;

When the current phasor of limit phase equals limiting current vector, the stall carrying out magneto heats up and tests;

The described selected limit is specially mutually:

Using with Space current vector angle minimum one as limit phase;

Offset angle on described calculating stall position between Space current vector and limit phase is specially:

Initial deflection angle θ between computer memory current phasor and prima facies, then obtain described offset angle by the geometric relationship of initial deflection angle and three phase coordinates.

2. method according to claim 1, it is characterized in that, the initial deflection angle θ between described computer memory current phasor and prima facies is specially:

According to torque capacity minimum current control algorithm, Space current vector is decomposed into exciting current i _dwith torque current i _q;

Extract initial offset θ ₁, and according to exciting current i _dwith torque current i _qcomputer memory current phasor and exciting current i _dbetween angle theta ₂;

Then θ=θ ₁+ θ ₂.

3. method according to claim 2, is characterized in that, described according to exciting current i _dwith torque current i _qcomputer memory current phasor and exciting current i _dbetween angle theta ₂be specially:

According to formula ${\mathrm{\θ}}_2=arctan\frac{i_q}{i_d}+\frac{\mathrm{\π}}{2}$ Obtain θ ₂.

4. method according to Claims 2 or 3, is characterized in that, carries out correction be specially according to described offset angle to Space current vector:

Directly initial offset θ is revised by the control program of magneto ₁, Space current vector and the limit are coincided;

Or pass through the control program correction exciting current i of magneto _dwith torque current i _q, Space current vector and the limit are coincided.

5. method according to claim 4, is characterized in that, described correction initial offset θ ₁be specially:

By initial offset θ ₁increasing or reducing α, α is the angle of offset angle.

6. method according to claim 5, is characterized in that, described correction exciting current i _dwith torque current i _qbe specially:

According to formula $\left(\begin{array}{c}{i}_d^{\′}\\ i_q^{\′}\end{array}\right)=\left(\begin{array}{cc}cos\mathrm{\α}& -sin\mathrm{\α}\\ sin\mathrm{\α}& \cos \mathrm{\α}\end{array}\right)\left(\begin{array}{c}{i}_d\\ i_q\end{array}\right)$ Revise;

Wherein, i _d' be revised exciting current; i _q' be revised torque current; α is the angle of offset angle.

7. a magneto stall test macro, is characterized in that, described system specifically comprises:

Position module, for determining the Space current vector on stall position; Selected limit phase;

Computing module, for calculating the offset angle on stall position between Space current vector and limit phase;

Control module, for revising Space current vector according to described offset angle, Space current vector and the limit are coincided, the current phasor of limit phase equals limiting current vector;

Test module, for when the current phasor of limit phase equals limiting current vector, the stall carrying out magneto heats up and tests;

Described position module is selected the limit and is specially mutually:

Using with Space current vector angle minimum one as limit phase;

The offset angle that described computing module calculates on stall position between Space current vector and limit phase is specially:

Initial deflection angle θ between computer memory current phasor and prima facies, then obtain described offset angle by the geometric relationship of initial deflection angle and three phase coordinates.