CN103929112B - A kind of linear electric motors measurement of mutual inductance method and system - Google Patents

Abstract

The invention discloses a kind of linear electric motors measurement of mutual inductance method and system, under the method passes through the state run with fixed speed in described linear motor train, the slip frequency angular rate ω of given linear electric motors _sbe zero, make this measurement be equal to no-load test in laboratory; And 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 | when changing in its span, the linear electric motors mutual inductance value L within the scope of full field can be obtained _m; And described linear electric motors measurement of mutual inductance method is the measurement carried out at the scene, ensure that accuracy and the precision of measurement, is applicable to the high performance control of direct current machine.

Description

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

Technical field

The present invention relates to motor control technology field, particularly relate 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 the track drawing systems technology of a 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: carry out no-load test in laboratory, mutual inductance value is calculated by the data of no-load test, but this method is mainly for the measurement of mutual inductance of asynchronous machine, and the form that the short elementary length of the many employings of current track traction linear electric motors is secondary, its secondary tablet for laying in orbit, linear electric motors are made not possess the condition of carrying out parameter measurement in laboratory, simultaneously the method can only measure the mutual inductance value under specified magnetic field conditions, can not react the mutual inductance value under other magnetic field conditions; 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 a kind of measurement of mutual inductance method of applicable railway traffic linear motor at present, the situation of mutual inductance under different magnetic field intensity can be reacted, certain required precision can be met 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 the measurement of mutual inductance that can not realize under different magnetic field intensity, and the problem that precision is low.

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

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

Under the state that described linear motor train is run with fixed speed, the slip frequency angular rate ω 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 fast Fourier transform is carried out to described A phase current, generate and the 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 voltage magnitudes 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 voltage magnitudes 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 _baseobtain by following account form:

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

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 angular rate ω _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 voltage magnitudes 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 PI adjustment is carried out to described first difference and the second difference, 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 the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis respectively _{s α}with torque voltage magnitudes U _{s β}.

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

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

Slip frequency angular rate to cell, under the state run with fixed speed in described linear motor train, the slip frequency angular rate ω 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 and the 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 voltage magnitudes 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 voltage magnitudes 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 _baseobtain by following account form:

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

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, generating and exporting mechanical angle speed omega _m;

The stator frequency electrical degree acquiring unit that input is connected to the output of the output of cell and described mechanical angle speed acquiring unit with described slip frequency angular rate respectively, for gathering described mechanical angle speed omega _mand described slip frequency angular rate ω _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 first subtrator and the output of described second subtrator respectively, for carrying out PI adjustment to described first difference and the second difference respectively, generating and exporting 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 the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis respectively _{s α}with torque voltage magnitudes U _{s β}.

Preferably, also comprise:

The PWM 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 voltage magnitudes U _{s β}and the direct voltage that power source bus exports carries out pwm pulse modulation, generates and exports modulating pulse;

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

As can be seen from above-mentioned technical scheme, linear electric motors measurement of mutual inductance method disclosed by the invention, by under the state run with fixed speed in described linear motor train, the slip frequency angular rate ω of given linear electric motors _sbe zero, make this measurement be equal to 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 fast Fourier transform is carried out to the A phase current of linear electric motors, generate and the 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 voltage magnitudes 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 | when changing in its span, the linear electric motors mutual inductance value L within the scope of full field can be obtained _m; And described linear electric motors measurement of mutual inductance method is the measurement carried out at the scene, ensure that accuracy and the precision of measurement, 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, 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 only 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 linear electric motors measurement of mutual inductance method flow diagram disclosed in the embodiment of the present invention;

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

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

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

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present invention, be clearly and completely described the technical scheme in the embodiment of the present invention, obviously, described embodiment is only 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.

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

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

Under S101, the state run with fixed speed in described linear motor train, the slip frequency angular rate ω of given linear electric motors _sbe zero;

First control described linear motor train to run with fixed speed, facilitate the follow-up current detecting to its linear electric motors; Meanwhile, the slip frequency angular rate ω of given linear electric motors _sbe zero, make this measurement be equal to 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;

About the perunit value of the given amplitude in described magnetic field | ψ | problem, because the mutual inductance size of described linear electric motors mainly determines by two factors: size of gaps and magnetic field are strong and weak.Suppose that size of gaps is consistent, the size of so mutual inductance determines primarily of magnetic field power.Therefore needing in each magnetic field to fixing, measuring the size of mutual inductance value.The i.e. perunit value of given amplitude in magnetic field | ψ | to fixing on (concrete size is determined according to different motor) between 1.1 ~ 0.3 equidistant value, thus the mutual inductance value obtained within the scope of full field, the truth of comprehensive reaction mutual inductance value, ensure that 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 | when being 1, illustrate that magnetic field is now specified magnetic field.

Fixed magnetic field is given simultaneously, can also judge the situation with air gap in analysis circuit, for detection line air gap situation by measuring mutual inductance value completely.

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

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

S104, the exciting voltage value U gathered in static two phase coordinate system alpha-beta reference axis _{s α}with torque voltage magnitudes 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 voltage magnitudes 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.

Linear electric motors measurement of mutual inductance method disclosed in the present embodiment, by said process, when the perunit value of the given amplitude in described magnetic field | ψ | when changing in its span, the linear electric motors mutual inductance value L within the scope of full field can be obtained _m; And described linear electric motors measurement of mutual inductance method is the measurement carried out at the scene, ensure that accuracy and the precision of measurement, 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 angular rate ω _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 subsequent line motor mutual inductance value L _mcalculating provide Data Source.

What deserves to be explained is, step S201 and S202 can carry out the optional position before step S105, as long as ensure 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 PI adjustment is carried out to described first difference and the second difference, 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 the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis respectively _{s α}with torque voltage magnitudes 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 voltage magnitudes U _{s β}source mode set forth, be the first-harmonic effective value U of follow-up phase voltage _basecalculating provide Data Source.

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

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

Slip frequency angular rate is to cell 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 angular rate runs with fixed speed in described linear motor train to cell 101, the slip frequency angular rate ω of given linear electric motors _sbe zero; Given value of current unit 102 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; Fast Fourier transform unit 103 gathers the A phase current of described linear electric motors, and carries out fast Fourier transform to described A phase current, generates and the effective value I of the fundametal compoment of output current _base; Mutual inductance identification unit 104 gathers the exciting voltage value U in static two phase coordinate system alpha-beta reference axis _{s α}with torque voltage magnitudes 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 voltage magnitudes 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.

Linear electric motors measurement of mutual inductance system disclosed in the present embodiment, when the perunit value of the given amplitude in described magnetic field | ψ | when changing in its span, the linear electric motors mutual inductance value L within the scope of full field can be obtained _m; And described linear electric motors measurement of mutual inductance system is applied to in-site measurement, ensure that accuracy and the precision of measurement, is applicable to the high performance control of described direct current machine.

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

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

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 to the output of the output of cell 101 and mechanical angle speed acquiring unit 105 with slip frequency angular rate respectively.

Wherein, mechanical angle speed acquiring unit 105 obtains the rotor speed of described linear electric motors, generates and exports mechanical angle speed omega _m; Stator frequency electrical degree acquiring unit 106 gathers described mechanical angle speed omega _mand described slip frequency angular rate ω _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 that detects 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; First subtrator 109 is by described given exciting current i _sddeduct described exciting current detected value i _sd-act, obtain the first difference; 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 adjustment to described first difference and the second difference respectively, generates and exports 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 the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis respectively _{s α}with torque voltage magnitudes U _{s β}.

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

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

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

Wherein, PWM unit 113 is to the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis _{s α}with torque voltage magnitudes U _{s β}and the direct voltage that power source bus exports carries out pwm pulse modulation, generates and exports modulating pulse; The direct voltage that described power source bus exports, according to described modulating pulse, is converted to alternating current by inversion unit 114, supply linear electric motors M.

In this specification, each embodiment adopts the mode of going forward one by one to describe, and what each embodiment stressed is the difference with other embodiments, between each embodiment identical similar portion mutually see.

To the above-mentioned explanation of the disclosed embodiments, professional and technical personnel in the field are realized or uses the present invention.To be apparent for those skilled in the art to the multiple amendment of these embodiments, General Principle as defined herein can without departing from the spirit or scope of the present invention, realize in other embodiments.Therefore, the present invention can not be restricted to these embodiments shown in this article, but will meet the widest scope consistent with principle disclosed herein and features of novelty.

Claims (8)

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

Under the state that described linear motor train is run with fixed speed, the slip frequency angular rate ω 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 fast Fourier transform is carried out to described A phase current, generate and the 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 voltage magnitudes 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 voltage magnitudes 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 first-harmonic effective value U of described phase voltage _baseobtain by following account form:

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

2. 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 angular rate ω _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.

3. linear electric motors measurement of mutual inductance method according to claim 2, 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 voltage magnitudes 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 PI adjustment is carried out to described first difference and the second difference, 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 the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis respectively _{s α}with torque voltage magnitudes U _{s β}.

4. 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.

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

Slip frequency angular rate to cell, under the state run with fixed speed in described linear motor train, the slip frequency angular rate ω 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 and the 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 voltage magnitudes 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 voltage magnitudes 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 first-harmonic effective value U of described phase voltage _baseobtain by following account form:

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

6. linear electric motors measurement of mutual inductance system according to claim 5, is characterized in that, 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, generating and exporting mechanical angle speed omega _m;

The stator frequency electrical degree acquiring unit that input is connected to the output of the output of cell and described mechanical angle speed acquiring unit with described slip frequency angular rate respectively, for gathering described mechanical angle speed omega _mand described slip frequency angular rate ω _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.

7. linear electric motors measurement of mutual inductance system according to claim 6, is characterized in that, 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 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 first subtrator and the output of described second subtrator respectively, for carrying out PI adjustment to described first difference and the second difference respectively, generating and exporting 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 the exciting voltage value U in described static two phase coordinate system alpha-beta reference axis respectively _{s α}with torque voltage magnitudes U _{s β}.

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

The PWM 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 voltage magnitudes U _{s β}and the direct voltage that power source bus exports carries out pwm pulse modulation, generates and exports modulating pulse;

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