CN103929112A - Linear motor mutual induction measuring method and system - Google Patents

Abstract

The invention discloses a linear motor mutual induction measuring method. Due to the fact that under the state that a linear motor train operates at a fixed speed, the slip frequency electric angle speed omega s given to the linear motor is zero, and therefore the measurement is equal to a no-load test in a test room; a certain calculation relation exists between the mutual inductance value Lm of the linear motor and the per unit value |Psi| of the given amplitude of a magnetic field, and when the per unit value |Psi| of the given amplitude of the magnetic field varies within a value range, the mutual inductance value Lm of the linear motor in the whole magnetic field range can be obtained. In addition, the linear motor mutual measuring method is used for performing measurement on the spot, the measurement accuracy and precision are ensured, and the linear motor mutual induction measuring method is suitable for high-performance control of the linear motor.

Description

A kind of linear electric motors measurement of mutual inductance method and system

Technical field

The present invention relates to electric machines control technology field, relate in particular to a kind of linear electric motors measurement of mutual inductance method and system.

Background technology

Linear induction motor system has that power performance is good, climbing capacity is strong, noise is little, it is little to vibrate and the feature such as project cost is low, becomes track drawing systems technology of new generation.The High Performance Control Strategies of linear electric motors depends on the parameter of electric machine accurately, and linear electric motors mutual inductance is as linear electric motors key parameter, and the accuracy of its value will directly affect the control performance of linear electric motors.

In prior art, method of measurement for described linear electric motors mutual inductance mainly contains two kinds: in laboratory, carry out no-load test, data by no-load test are calculated mutual inductance value, but this method is mainly for the measurement of mutual inductance of asynchronous machine, and the linear electric motors secondary forms of short elementary length that adopt for current track traction more, it is secondary is the tablet of laying in orbit, make linear electric motors not possess the condition of carrying out parameter measurement in laboratory, the method can only be measured the mutual inductance value in the situation of specified magnetic field simultaneously, can not react the mutual inductance value in other magnetic field situations; Another adopts the parameter measurement based on step response, utilize the parameter of the step response estimation motor of voltage or electric current, these class methods are a kind of static tests, are applicable to carrying out the occasion of no-load test, but its certainty of measurement, accuracy and comprehensive all inadequate.

Therefore lack at present a kind of measurement of mutual inductance method of applicable railway traffic linear motor, can react the situation of mutual inductance under different magnetic field intensity, can meet certain required precision again.

Summary of the invention

In view of this, the invention provides a kind of linear electric motors measurement of mutual inductance method and system, to solve in prior art, can not realize the measurement of mutual inductance under different magnetic field intensity, and the low problem of precision.

To achieve these goals, the existing scheme proposing is as follows:

A linear electric motors measurement of mutual inductance method, is applied to, in the controller in linear electric motors train one joint compartment, comprising:

Under state at described linear electric motors train with fixed speed operation, the slip frequency electric angle speed omega of given linear electric motors _sbe zero;

According to $\left\{\begin{array}{c}{i}_{\mathrm{sd}}=\left|\mathrm{\ψ}\right|\×i_f\\ i_{\mathrm{sq}}=0\end{array}\right.$ Generate and export given exciting current i _sdwith torque current i _sq; Wherein, | ψ | be the perunit value of the given amplitude in magnetic field, i _ffor rated exciting current value;

Gather the A phase current of described linear electric motors, and described A phase current is carried out to fast Fourier transform, generate the also effective value I of the fundametal compoment of output current _base;

Gather the exciting voltage value U in static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}, and in conjunction with the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}, calculate and export the first-harmonic effective value U of phase voltage _base;

Gather stator frequency electrical degree ω ₁and the effective value I of the fundametal compoment of described electric current _base, and according to L _m=U _base(I _base* ω ₁) calculate linear electric motors mutual inductance value L _m.

Preferably, the first-harmonic effective value U of described phase voltage _baseby following account form, obtain:

$U_{\mathrm{base}}=\sqrt{{U_{\mathrm{a\α}}}^2+{U_{\mathrm{s\β}}}^2}/\sqrt{2}.$

Preferably, at described collection stator frequency electrical degree ω ₁step before also comprise:

Obtain the rotor speed of described linear electric motors, generate and export mechanical angle speed omega _m;

Gather described mechanical angle speed omega _mand described slip frequency electric angle speed omega _s, and according to ω ₁=ω _m* P _n+ ω _scalculate and export described stator frequency electrical degree ω ₁; Wherein, P _nfor number of pole-pairs.

Preferably, the exciting voltage value U in the static two phase coordinate system alpha-beta reference axis of described collection _{s α}with torque magnitude of voltage U _{s β}also comprise before:

Gather described stator frequency electrical degree ω ₁, and to described stator frequency electrical degree ω ₁carry out integration, generate and output rotor flux linkage space position angle θ ₁;

Gather the stator current detected value of described linear electric motors, and described rotor flux locus angle θ ₁, and according to described rotor flux locus angle θ ₁the stator current detected value of described linear electric motors is decomposed into exciting current detected value i _sd-actwith torque current detected value i _sq-act;

With described given exciting current i _sddeduct described exciting current detected value i _sd-act, obtain the first difference; With described given torque current i _sqdeduct described torque current detected value i _sq-act, obtain the second difference;

Respectively described the first difference and the second difference are carried out to PI adjusting, generate and export exciting voltage U _smwith torque voltage U _st;

According to described rotor flux locus angle θ ₁, by described exciting voltage U _smwith torque voltage U _stbe converted to respectively the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}.

Preferably, the perunit value of the given amplitude in described magnetic field | ψ | value is between 1.1～0.3.

A linear electric motors measurement of mutual inductance system, is applied to, in the controller in linear electric motors train one joint compartment, comprising:

Slip frequency electric angle speed preset unit, under the state with fixed speed operation at described linear electric motors train, the slip frequency electric angle speed omega of given linear electric motors _sbe zero;

Given value of current unit, for basis $\left\{\begin{array}{c}{i}_{\mathrm{sd}}=\left|\mathrm{\ψ}\right|\×i_f\\ i_{\mathrm{sq}}=0\end{array}\right.$ Generate and export given exciting current i _sdwith torque current i _sq; Wherein, | ψ | be the perunit value of the given amplitude in magnetic field, i _ffor rated exciting current value;

The fast Fourier transform unit that input is connected with linear electric motors, for gathering the A phase current of described linear electric motors, and carries out fast Fourier transform to described A phase current, generates the also effective value I of the fundametal compoment of output current _base;

The mutual inductance identification unit that input is connected with the output of described fast Fourier transform unit, for gathering the exciting voltage value U in static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}, and in conjunction with the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}, calculate and export the first-harmonic effective value U of phase voltage _base; Gather stator frequency electrical degree ω ₁and the effective value I of the fundametal compoment of described electric current _base, and according to L _m=U _base(I _base* ω ₁) calculate linear electric motors mutual inductance value L _m.

Preferably, the first-harmonic effective value U of described phase voltage _baseby following account form, obtain:

$U_{\mathrm{base}}=\sqrt{{U_{\mathrm{a\α}}}^2+{U_{\mathrm{s\β}}}^2}/\sqrt{2}.$

Preferably, also comprise:

The mechanical angle speed acquiring unit that input is connected with described linear electric motors, for obtaining the rotor speed of described linear electric motors, generates and exports mechanical angle speed omega _m;

The stator frequency electrical degree acquiring unit that input is connected with the output of described slip frequency electric angle speed preset unit and the output of described mechanical angle speed acquiring unit respectively, for gathering described mechanical angle speed omega _mand described slip frequency electric angle speed omega _s, according to ω ₁=ω _m* P _n+ ω _scalculate and export described stator frequency electrical degree ω ₁; Wherein, P _nfor number of pole-pairs.

Preferably, also comprise:

The rotor flux locus angle acquiring unit that input is connected with the output of described stator frequency electrical degree acquiring unit, for gathering described stator frequency electrical degree ω ₁, and to described stator frequency electrical degree ω ₁carry out integration, generate and output rotor flux linkage space position angle θ ₁;

The detection electric current acquiring unit that input is connected with output and the described linear electric motors of described rotor flux locus angle acquiring unit respectively, for gathering the stator current detected value of described linear electric motors, and described rotor flux locus angle θ ₁, and according to described rotor flux locus angle θ ₁the stator current detected value of described linear electric motors is decomposed into exciting current detected value i _sd-actwith torque current detected value i _sq-act;

The first subtrator that input is connected with the output of described given electric current acquiring unit and the output of described detection electric current acquiring unit respectively, for deducting described exciting current detected value i by described given exciting current isd _sd-act, obtain the first difference;

The second subtrator that input is connected with the output of described given electric current acquiring unit and the output of described detection electric current acquiring unit respectively, for by described given torque current i _sqdeduct described torque current detected value i _sq-act, obtain the second difference;

The PI regulon that input is connected with the output of described the first subtrator and the output of described the second subtrator respectively, for respectively described the first difference and the second difference being carried out to PI adjusting, generates and exports exciting voltage U _smwith torque voltage U _st;

The voltage coordinate converter unit that input is connected with the output of described PI regulon and the output of described rotor flux locus angle acquiring unit respectively, for according to described rotor flux locus angle θ ₁, by described exciting voltage U _smwith torque voltage U _stbe converted to respectively the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}.

Preferably, also comprise:

The PWM modulating unit that input is connected with the output of described voltage coordinate converter unit, for the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}and the direct voltage of power source bus output carries out pwm pulse modulation, generate and export modulating pulse;

Be connected in the output of described PWM modulating unit and the inversion unit between described linear electric motors, for according to described modulating pulse, the direct voltage of described power source bus output be converted to alternating current, supply with described linear electric motors.

From above-mentioned technical scheme, can find out, linear electric motors measurement of mutual inductance method disclosed by the invention, under the state with fixed speed operation at described linear electric motors train, the slip frequency electric angle speed omega of given linear electric motors _sbe zero, make this measurement be equal to the no-load test in laboratory; Basis again $\left\{\begin{array}{c}{i}_{\mathrm{sd}}=\left|\mathrm{\ψ}\right|\×i_f\\ i_{\mathrm{sq}}=0\end{array}\right.$ Generate and export given exciting current i _sdwith torque current i _sq; Then the A phase current of linear electric motors is carried out to fast Fourier transform, generate the also effective value I of the fundametal compoment of output current _base; Again in conjunction with the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}, calculate and export the first-harmonic effective value U of phase voltage _base; Finally gather stator frequency electrical degree ω ₁and the effective value I of the fundametal compoment of described electric current _base, and according to L _m=U _base(I _base* ω ₁) calculate linear electric motors mutual inductance value L _m; From said process, described linear electric motors mutual inductance value L _mand the perunit value of the given amplitude in magnetic field | ψ | between there is certain calculated relationship, when the perunit value of the given amplitude in described magnetic field | ψ | while changing, can obtain the linear electric motors mutual inductance value L within the scope of full field in its span _m; And the measurement of described linear electric motors measurement of mutual inductance method for carrying out at the scene, has guaranteed accuracy and the precision measured, is applicable to the high performance control of described direct current machine.

Accompanying drawing explanation

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

Fig. 1 is the disclosed linear electric motors measurement of mutual inductance of embodiment of the present invention method flow diagram;

Fig. 2 is the disclosed linear electric motors measurement of mutual inductance of another embodiment of the present invention method flow diagram;

Fig. 3 is the disclosed linear electric motors measurement of mutual inductance of another embodiment of the present invention method flow diagram;

Fig. 4 is the disclosed linear electric motors measurement of mutual inductance of another embodiment of the present invention system construction drawing.

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is only the present invention's part embodiment, rather than whole embodiment.Embodiment based in the present invention, those of ordinary skills, not making the every other embodiment obtaining under creative work prerequisite, belong to the scope of protection of the invention.

The invention provides a kind of linear electric motors measurement of mutual inductance method, to solve in prior art, can not realize the measurement of mutual inductance under different magnetic field intensity, and the low problem of precision.

Concrete, described linear electric motors measurement of mutual inductance method, is applied to, in the controller in linear electric motors train one joint compartment, as shown in Figure 1, comprising:

Under S101, the state at described linear electric motors train with fixed speed operation, the slip frequency electric angle speed omega of given linear electric motors _sbe zero;

First control described linear electric motors train and move with fixed speed, facilitate the follow-up current detecting to its linear electric motors; Meanwhile, the slip frequency electric angle speed omega of given linear electric motors _sbe zero, make this measurement be equal to the no-load test in laboratory.

S102, basis $\left\{\begin{array}{c}{i}_{\mathrm{sd}}=\left|\mathrm{\ψ}\right|\×i_f\\ i_{\mathrm{sq}}=0\end{array}\right.$ Generate and export given exciting current i _sdwith torque current i _sq; Wherein, | ψ | be the perunit value of the given amplitude in magnetic field, i _ffor rated exciting current value;

Perunit value about the given amplitude in described magnetic field | ψ | problem, because the mutual inductance size of described linear electric motors is determined by two factors mainly: size of gaps and magnetic field are strong and weak.Suppose that size of gaps is consistent, the size of mutual inductance mainly determines by magnetic field is strong and weak so.Therefore need to be fixed in each magnetic field, be measured the size of mutual inductance value.At the perunit value of the given amplitude in magnetic field | ψ | give and fix between 1.1～0.3 (concrete size determine according to different motors) equidistantly value, thereby obtain the mutual inductance value within the scope of full field, react the truth of mutual inductance value comprehensively, guarantee the accuracy of mutual inductance value, can be used in the high performance control of linear electric motors.

In addition, when the perunit value of the given amplitude in described magnetic field | ψ | while being 1, illustrate that magnetic field is now specified magnetic field.

Simultaneously fixed magnetic field is given, by measure mutual inductance value completely can also judge with analysis circuit on the situation of air gap, for detection of circuit air gap situation.

S103, gather the A phase current of described linear electric motors, and described A phase current is carried out to fast Fourier transform, generate and the effective value I of the fundametal compoment of output current _base;

When the stable operation of described linear electric motors train is after a speed point, can gather A phase current and carry out F fast Fourier transform, for follow-up calculating provides numerical value.

S104, gather the exciting voltage value U in static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}, and in conjunction with the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}, calculate and export the first-harmonic effective value U of phase voltage _base;

Preferably, the first-harmonic effective value U of described phase voltage _basecomputing formula be: $U_{\mathrm{base}}=\sqrt{{U_{\mathrm{a\α}}}^2+{U_{\mathrm{s\β}}}^2}/\sqrt{2}.$

S105, collection stator frequency electrical degree ω ₁and the effective value I of the fundametal compoment of described electric current _base, and according to L _m=U _base(I _base* ω ₁) calculate linear electric motors mutual inductance value L _m.

The disclosed linear electric motors measurement of mutual inductance of the present embodiment method, by said process, when the perunit value of the given amplitude in described magnetic field | ψ | while changing, can obtain the linear electric motors mutual inductance value L within the scope of full field in its span _m; And the measurement of described linear electric motors measurement of mutual inductance method for carrying out at the scene, has guaranteed accuracy and the precision measured, is applicable to the high performance control of described direct current machine.

Preferably, as shown in Figure 2, before step S105, described linear electric motors measurement of mutual inductance method also comprises:

S201, obtain the rotor speed of described linear electric motors, generate and export mechanical angle speed omega _m;

S202, gather described mechanical angle speed omega _mand described slip frequency electric angle speed omega _s, according to ω ₁=ω _m* P _n+ ω _scalculate and export described stator frequency electrical degree ω ₁; Wherein, P _nfor number of pole-pairs;

Above-mentioned two steps are stator frequency electrical degree ω ₁source mode set forth, be follow-up linear electric motors mutual inductance value L _mcalculating Data Source is provided.

What deserves to be explained is, step S201 and S202 can carry out the optional position before step S105, as long as guarantee described stator frequency electrical degree ω ₁collection, Fig. 2 is a kind of example, herein and be not specifically limited.

Preferably, as shown in Figure 3, before step S104, described linear electric motors measurement of mutual inductance method also comprises:

S301, gather described stator frequency electrical degree ω ₁, and to described stator frequency electrical degree ω ₁carry out integration, generate and output rotor flux linkage space position angle θ ₁;

S302, gather the stator current detected value of described linear electric motors and described rotor flux locus angle θ ₁, and according to described rotor flux locus angle θ ₁the stator current detected value of described linear electric motors is decomposed into exciting current detected value i _sd-actwith torque current detected value i _sq-act;

S303, with described given exciting current i _sddeduct described exciting current detected value i _sd-act, obtain the first difference; With described given torque current i _sqdeduct described torque current detected value i _sq-act, obtain the second difference;

S304, respectively described the first difference and the second difference are carried out to PI adjusting, generate and export exciting voltage U _smwith torque voltage U _st;

S305, according to described rotor flux locus angle θ ₁, by described exciting voltage U _smwith torque voltage U _stbe converted to respectively the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}.

Above-mentioned steps is the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}source mode set forth, be the first-harmonic effective value U of follow-up phase voltage _basecalculating Data Source is provided.

What deserves to be explained is, the step S301 in the present embodiment need to gather described stator frequency electrical degree ω ₁so, after should being listed in step S201 and S202, require before step S201 and S202 be listed in step S104; But the order of step S201 and S202 and step S103 is without restriction, and Fig. 3 is only a kind of example.

Another embodiment of the present invention also provides a kind of linear electric motors measurement of mutual inductance system, is applied to, in the controller in linear electric motors train one joint compartment, as shown in Figure 4, comprising:

Slip frequency electric angle speed preset unit 101;

Given value of current unit 102;

The fast Fourier transform unit 103 that input is connected with linear electric motors M;

The mutual inductance identification unit 104 that input is connected with the output of fast Fourier transform unit 103.

Concrete operation principle is:

Under the state that slip frequency electric angle speed preset unit 101 moves with fixed speed at described linear electric motors train, the slip frequency electric angle speed omega of given linear electric motors _sbe zero; Given value of current unit 102 bases $\left\{\begin{array}{c}{i}_{\mathrm{sd}}=\left|\mathrm{\ψ}\right|\×i_f\\ i_{\mathrm{sq}}=0\end{array}\right.$ Generate and export given exciting current i _sdwith torque current i _sq; Wherein, | ψ | be the perunit value of the given amplitude in magnetic field, i _ffor rated exciting current value; Fast Fourier transform unit 103 gathers the A phase current of described linear electric motors, and described A phase current is carried out to fast Fourier transform, generates the also effective value I of the fundametal compoment of output current _base; The exciting voltage value U that mutual inductance identification unit 104 gathers in static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}, and in conjunction with the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}, calculate and export the first-harmonic effective value U of phase voltage _base; Gather stator frequency electrical degree ω ₁and the effective value I of the fundametal compoment of described electric current _base, and according to L _m=U _base(I _base* ω 1) calculate linear electric motors mutual inductance value L _m.

The disclosed linear electric motors measurement of mutual inductance of the present embodiment system, when the perunit value of the given amplitude in described magnetic field | ψ | while changing, can obtain the linear electric motors mutual inductance value L within the scope of full field in its span _m; And described linear electric motors measurement of mutual inductance system applies, in in-site measurement, has guaranteed accuracy and the precision measured, is applicable to the high performance control of described direct current machine.

Preferably, the first-harmonic effective value U of described phase voltage _baseby following account form, obtain:

$U_{\mathrm{base}}=\sqrt{{U_{\mathrm{a\α}}}^2+{U_{\mathrm{s\β}}}^2}/\sqrt{2}.$

Preferably, as shown in Figure 4, described linear electric motors measurement of mutual inductance system also comprises:

The mechanical angle speed acquiring unit 105 that input is connected with linear electric motors M;

The stator frequency electrical degree acquiring unit 106 that input is connected with the output of slip frequency electric angle speed preset unit 101 and the output of mechanical angle speed acquiring unit 105 respectively.

Wherein, mechanical angle speed acquiring unit 105 obtains the rotor speed of described linear electric motors, generates and export mechanical angle speed omega _m; Stator frequency electrical degree acquiring unit 106 gathers described mechanical angle speed omega _mand described slip frequency electric angle speed omega _s, and according to ω ₁=ω _m* P _n+ ω _scalculate and export described stator frequency electrical degree ω ₁; Wherein, P _nfor number of pole-pairs.

Preferably, as shown in Figure 4, described linear electric motors measurement of mutual inductance system also comprises:

The rotor flux locus angle acquiring unit 107 that input is connected with the output of stator frequency electrical degree acquiring unit 106;

The detection electric current acquiring unit 108 that input is connected with output and the linear electric motors M of rotor flux locus angle acquiring unit 107 respectively;

The first subtrator 109 and the second subtrator 110 that input is connected with the output of given electric current acquiring unit 102 and the output of detection electric current acquiring unit 108 respectively;

The PI regulon 111 that input is connected with the output of the first subtrator 109 and the output of the second subtrator 110 respectively;

The voltage coordinate converter unit 112 that input is connected with the output of PI regulon 111 and the output of rotor flux locus angle acquiring unit 107 respectively.

Concrete operation principle is:

Rotor flux locus angle acquiring unit 107 gathers described stator frequency electrical degree ω ₁, and to described stator frequency electrical degree ω ₁carry out integration, generate and output rotor flux linkage space position angle θ ₁; Detect the stator current detected value that electric current acquiring unit 108 gathers described linear electric motors, and described rotor flux locus angle θ ₁, and according to described rotor flux locus angle θ ₁the stator current detected value of described linear electric motors is decomposed into exciting current detected value i _sd-actwith torque current detected value i _sq-act; The first subtrator 109 is by described given exciting current i _sddeduct described exciting current detected value i _sd-act, obtain the first difference; The second subtrator 110 is by described given torque current i _sqdeduct described torque current detected value i _sq-act, obtain the second difference; PI regulon 111 carries out PI adjusting to described the first difference and the second difference respectively, generates and export exciting voltage U _smwith torque voltage U _st; Voltage coordinate converter unit 112 is according to described rotor flux locus angle θ ₁, by described exciting voltage U _smwith torque voltage U _stbe converted to respectively the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}.

Preferably, as shown in Figure 4, described linear electric motors measurement of mutual inductance system also comprises:

The PWM modulating unit 113 that input is connected with the output of voltage coordinate converter unit 112;

Be connected in the output of PWM modulating unit 113 and the inversion unit 114 between linear electric motors M.

Wherein, the exciting voltage value U in 113 pairs of described static two phase coordinate system alpha-beta reference axis of PWM modulating unit _{s α}with torque magnitude of voltage U _{s β}and the direct voltage of power source bus output carries out pwm pulse modulation, generate and export modulating pulse; Inversion unit 114, according to described modulating pulse, is converted to alternating current by the direct voltage of described power source bus output, supplies with linear electric motors M.

In this specification, each embodiment adopts the mode of going forward one by one to describe, and each embodiment stresses is the difference with other embodiment, between each embodiment identical similar part mutually referring to.

Above-mentioned explanation to the disclosed embodiments, makes professional and technical personnel in the field can realize or use the present invention.To the multiple modification of these embodiment, will be apparent for those skilled in the art, General Principle as defined herein can, in the situation that not departing from the spirit or scope of the present invention, realize in other embodiments.Therefore, the present invention will can not be restricted to these embodiment shown in this article, but will meet the widest scope consistent with principle disclosed herein and features of novelty.

Claims (10)

1. a linear electric motors measurement of mutual inductance method, is applied to, in the controller in linear electric motors train one joint compartment, it is characterized in that, comprising:

Under state at described linear electric motors train with fixed speed operation, the slip frequency electric angle speed omega of given linear electric motors _sbe zero;

According to $\left\{\begin{array}{c}{i}_{\mathrm{sd}}=\left|\mathrm{\ψ}\right|\×i_f\\ i_{\mathrm{sq}}=0\end{array}\right.$ Generate and export given exciting current i _sdwith torque current i _sq; Wherein, | ψ | be the perunit value of the given amplitude in magnetic field, i _ffor rated exciting current value;

Gather the A phase current of described linear electric motors, and described A phase current is carried out to fast Fourier transform, generate the also effective value I of the fundametal compoment of output current _base;

Gather the exciting voltage value U in static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}, and in conjunction with the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}, calculate and export the first-harmonic effective value U of phase voltage _base;

Gather stator frequency electrical degree ω ₁and the effective value I of the fundametal compoment of described electric current _base, and according to L _m=U _base(I _base* ω ₁) calculate linear electric motors mutual inductance value L _m.

2. linear electric motors measurement of mutual inductance method according to claim 1, is characterized in that, the first-harmonic effective value U of described phase voltage _baseby following account form, obtain:

$U_{\mathrm{base}}=\sqrt{{U_{\mathrm{a\α}}}^2+{U_{\mathrm{s\β}}}^2}/\sqrt{2}.$

3. linear electric motors measurement of mutual inductance method according to claim 1, is characterized in that, at described collection stator frequency electrical degree ω ₁step before also comprise:

Obtain the rotor speed of described linear electric motors, generate and export mechanical angle speed omega _m;

Gather described mechanical angle speed omega _mand described slip frequency electric angle speed omega _s, and according to ω ₁=ω _m* P _n+ ω _scalculate and export described stator frequency electrical degree ω ₁; Wherein, P _nfor number of pole-pairs.

4. linear electric motors measurement of mutual inductance method according to claim 3, is characterized in that, the exciting voltage value U in the static two phase coordinate system alpha-beta reference axis of described collection _{s α}with torque magnitude of voltage U _{s β}also comprise before:

Gather described stator frequency electrical degree ω ₁, and to described stator frequency electrical degree ω ₁carry out integration, generate and output rotor flux linkage space position angle θ ₁;

Gather the stator current detected value of described linear electric motors, and described rotor flux locus angle θ ₁, and according to described rotor flux locus angle θ ₁the stator current detected value of described linear electric motors is decomposed into exciting current detected value i _sd-actwith torque current detected value i _sq-act;

With described given exciting current i _sddeduct described exciting current detected value i _sd-act, obtain the first difference; With described given torque current i _sqdeduct described torque current detected value i _sq-act, obtain the second difference;

Respectively described the first difference and the second difference are carried out to PI adjusting, generate and export exciting voltage U _smwith torque voltage U _st;

According to described rotor flux locus angle θ ₁, by described exciting voltage U _smwith torque voltage U _stbe converted to respectively the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}.

5. linear electric motors measurement of mutual inductance method according to claim 1, is characterized in that, the perunit value of the given amplitude in described magnetic field | ψ | and value is between 1.1～0.3.

6. a linear electric motors measurement of mutual inductance system, is applied to, in the controller in linear electric motors train one joint compartment, it is characterized in that, comprising:

Slip frequency electric angle speed preset unit, under the state with fixed speed operation at described linear electric motors train, the slip frequency electric angle speed omega of given linear electric motors _sbe zero;

Given value of current unit, for basis $\left\{\begin{array}{c}{i}_{\mathrm{sd}}=\left|\mathrm{\ψ}\right|\×i_f\\ i_{\mathrm{sq}}=0\end{array}\right.$ Generate and export given exciting current i _sdwith torque current i _sq; Wherein, | ψ | be the perunit value of the given amplitude in magnetic field, i _ffor rated exciting current value;

The fast Fourier transform unit that input is connected with linear electric motors, for gathering the A phase current of described linear electric motors, and carries out fast Fourier transform to described A phase current, generates the also effective value I of the fundametal compoment of output current _base;

The mutual inductance identification unit that input is connected with the output of described fast Fourier transform unit, for gathering the exciting voltage value U in static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}, and in conjunction with the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}, calculate and export the first-harmonic effective value U of phase voltage _base; Gather stator frequency electrical degree ω ₁and the effective value I of the fundametal compoment of described electric current _base, and according to L _m=U _base(I _base* ω ₁) calculate linear electric motors mutual inductance value L _m.

7. linear electric motors measurement of mutual inductance system according to claim 6, is characterized in that, the first-harmonic effective value U of described phase voltage _baseby following account form, obtain:

$U_{\mathrm{base}}=\sqrt{{U_{\mathrm{a\α}}}^2+{U_{\mathrm{s\β}}}^2}/\sqrt{2}.$

8. linear electric motors measurement of mutual inductance system according to claim 6, is characterized in that, also comprises:

The mechanical angle speed acquiring unit that input is connected with described linear electric motors, for obtaining the rotor speed of described linear electric motors, generates and exports mechanical angle speed omega _m;

The stator frequency electrical degree acquiring unit that input is connected with the output of described slip frequency electric angle speed preset unit and the output of described mechanical angle speed acquiring unit respectively, for gathering described mechanical angle speed omega _mand described slip frequency electric angle speed omega _s, according to ω ₁=ω _m* P _n+ ω _scalculate and export described stator frequency electrical degree ω ₁; Wherein, P _nfor number of pole-pairs.

9. linear electric motors measurement of mutual inductance system according to claim 8, is characterized in that, also comprises:

The rotor flux locus angle acquiring unit that input is connected with the output of described stator frequency electrical degree acquiring unit, for gathering described stator frequency electrical degree ω ₁, and to described stator frequency electrical degree ω ₁carry out integration, generate and output rotor flux linkage space position angle θ ₁;

The detection electric current acquiring unit that input is connected with output and the described linear electric motors of described rotor flux locus angle acquiring unit respectively, for gathering the stator current detected value of described linear electric motors, and described rotor flux locus angle θ ₁, and according to described rotor flux locus angle θ ₁the stator current detected value of described linear electric motors is decomposed into exciting current detected value i _sd-actwith torque current detected value i _sq-act;

The first subtrator that input is connected with the output of described given electric current acquiring unit and the output of described detection electric current acquiring unit respectively, for by described given exciting current i _sddeduct described exciting current detected value i _sd-act, obtain the first difference;

The second subtrator that input is connected with the output of described given electric current acquiring unit and the output of described detection electric current acquiring unit respectively, for by described given torque current i _sqdeduct described torque current detected value i _sq-act, obtain the second difference;

The PI regulon that input is connected with the output of described the first subtrator and the output of described the second subtrator respectively, for respectively described the first difference and the second difference being carried out to PI adjusting, generates and exports exciting voltage U _smwith torque voltage U _st;

The voltage coordinate converter unit that input is connected with the output of described PI regulon and the output of described rotor flux locus angle acquiring unit respectively, for according to described rotor flux locus angle θ ₁, by described exciting voltage U _smwith torque voltage U _stbe converted to respectively the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}.

10. linear electric motors measurement of mutual inductance system according to claim 8, is characterized in that, also comprises:

The PWM modulating unit that input is connected with the output of described voltage coordinate converter unit, for the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque magnitude of voltage U _{s β}and the direct voltage of power source bus output carries out pwm pulse modulation, generate and export modulating pulse;

Be connected in the output of described PWM modulating unit and the inversion unit between described linear electric motors, for according to described modulating pulse, the direct voltage of described power source bus output be converted to alternating current, supply with described linear electric motors.