CN102611383B - Stator resistance on-line identification method and device - Google Patents

Abstract

The embodiment of the invention discloses a kind of stator resistance on-line identification method, comprise and judge whether motor is in stable state, if so, then obtain threephase stator electric current I _{s_abc}with threephase stator voltage U _{s_abc}; By described I _{s_abc}be oriented in the d direction of synchronous rotary dq coordinate system, calculate the component I in described d direction _{s_d}, or by described I _{s_abc}be oriented in synchronous rotary dq coordinate system q direction, calculate the component I in described q direction _{s_q}; Calculate lock phase angle theta _i, synchronous speed ω _s; According to described θ _icalculate described U _{s_abc}at the component U in described d direction _{s_d}with the component U in described q direction _{s_q}; Obtain stator magnetic linkage ψ _s, and calculate described ψ _sat the component ψ in described q direction _sq, or the component ψ in described d direction _sd; Stator resistance value R is calculated according to stator resistance computing formula _s.The invention solves the problem that existing discrimination method complexity is high.The embodiment of the invention also discloses a kind of stator resistance on-line identification device.

Description

Stator resistance on-line identification method and device

Technical field

The present invention relates to drive system of electric automobile control technology field, more particularly to a kind of stator resistance on-line identification method and device.

Background technology

, it is necessary to grasp accurate magnetic linkage information in the control process of drive system of electric automobile, it is therefore desirable to carry out flux linkage estimation.In the stator flux estimation chinese based on voltage model, the parameter of electric machine being related to only has stator resistance, therefore accurately on-line identification stator resistance, can improve the precision of flux linkage estimation.

Existing stator resistance on-line identification method mainly includes the discrimination method based on motor steady-state model and the discrimination method based on adaptation theory.

Discrimination method based on motor steady-state model, stator current and stator voltage according to detecting calculate the reactive power of motor, stator magnetic linkage, rotor flux, electromagnetic torque successively, and stator resistance is calculated according to above-mentioned result of calculation and the Stator resistance identification expression formula being derived by advance.Obviously, the method amount of calculation is very big.

The key point of Stator resistance identification method based on adaptation theory is adjusted by experiment repeatedly, it is determined that the suitable margin of error, error, the error based on active power or reactive power and the stator current of rotor flux d axis components such as based on voltage model and current model are in the error of the d durection components of synchronous rotary dq coordinate systems, and its process is very complicated.

Therefore, the complexity of stator resistance on-line identification how is reduced, the problem of as this area urgent need to resolve.

The content of the invention

In view of this, the invention provides a kind of stator resistance on-line identification method and device, to solve the problem of existing on-line identification method complexity is high.

To achieve the above object, the present invention provides following technical scheme：

A kind of stator resistance on-line identification method, including：

Judge whether motor is in stable state, if it is, obtaining threephase stator electric current I_{s_abc}With threephase stator voltage U_{s_abc}；

By the I_{s_abc}The d directions of synchronous rotary dq coordinate systems are oriented in, the component I in the d directions is calculated_{s_d}, or, by the I_{s_abc}Synchronous rotary dq coordinate system q directions are oriented in, the component I in the q directions is calculated_{s_q}；

Calculate lock phase angle theta_i, synchronous rotational speed ω_s；

According to the θ_iCalculate the U_{s_abc}Component U in the d directions_{s_d}With the component U in the q directions_{s_q}；

Obtain stator magnetic linkage ψ_s, and as the I_{s_abc}When being oriented in the d directions, the ψ is calculated_sComponent ψ in the q directions_sq, as the I_{s_abc}When being oriented in the q directions, the ψ is calculated_sComponent ψ in the d directions_sd；

Stator resistance value R is calculated according to stator resistance calculation formula_s；Wherein,

As the I_{s_abc}When being oriented in the d directions, the stator resistance calculation formula is $R_s=\frac{U_{s\_d}+{\mathrm{\ω}}_s{\mathrm{\ψ}}_{\mathrm{sq}}}{I_{s\_d}};$

As the I_{s_abc}When being oriented in the q directions, the stator resistance calculation formula is $R_s=\frac{U_{s\_q}-{\mathrm{\ω}}_s{\mathrm{\ψ}}_{\mathrm{sd}}}{I_{s\_q}}.$

Preferably, the acquisition ψ_sSpecially：Obtain magnetic linkage control ring set-point ψ_{s_ref}It is used as the ψ_sAmplitude | ψ_s|；

Calculate the ψ_sComponent ψ in the q directions_sqSpecially：Utilize formula ${\mathrm{\ψ}}_{\mathrm{sq}}=\sqrt{{{\mathrm{\ψ}}_{s\_\mathrm{ref}}}^2-{\left(\frac{U_{s\_q}}{{\mathrm{\ω}}_s}\right)}^2}$ Calculate the ψ_sq；

Calculate the ψ_sComponent ψ in the d directions_sdSpecially：Utilize formula ${\mathrm{\ψ}}_{\mathrm{sd}}=\sqrt{{{\mathrm{\ψ}}_{s\_\mathrm{ref}}}^2-{\left(\frac{U_{s\_d}}{{\mathrm{\ω}}_s}\right)}^2}$ Calculate the ψ_sd。

Preferably, it is described to judge whether motor specifically includes in stable state：

Calculate variation delta ω of the rotor speed of the motor in default time interval Δ T_r；

Judge the Δ ω_rWhether in default scope, if it is, the motor is in stable state.

Preferably, the Δ T is set as the time constant T of motor_r10 times.

Preferably, it is described to judge the Δ ω_rWhether include in default scope：Judge the Δ ω using hysteresis comparator_rWhether in default scope；

The default scope is interval [negative ring width, positive ring width].

A kind of stator resistance on-line identification device, including temporary stable state discriminator, sampling unit, stator current phaselocked loop, stator voltage coordinate transformation unit, stator magnetic linkage computing unit and stator resistance on-line identification unit；Wherein,

The temporary stable state discriminator, for judging whether motor is in stable state, if it is, triggering the sampling unit and described and stator magnetic linkage computing unit；

The sampling unit, for obtaining threephase stator electric current I_{s_abc}With threephase stator voltage U_{s_abc}；

The stator current phaselocked loop, for by the I_{s_abc}Synchronous rotary dq coordinate system d directions are oriented in, the component I in d directions is calculated_{s_d}, or, by the I_{s_abc}Synchronous rotary dq coordinate system q directions are oriented in, the component I in q directions is calculated_{s_q}, and calculate lock phase angle theta_iWith synchronous rotational speed ω_s；

The stator voltage coordinate transformation unit, for calculating obtained θ according to the stator current phaselocked loop_iCalculate the U_{s_abc}Component U in the d directions_{s_d}With the component U in the q directions_{s_q}；

The stator magnetic linkage computing unit, for obtaining stator magnetic linkage ψ_s, and as the I_{s_abc}When being oriented in the d directions, the ψ is calculated_sComponent ψ in the q directions_sq, as the I_{s_abc}When being oriented in the q directions, the ψ is calculated_sComponent ψ in the d directions_sd；

The stator resistance on-line identification unit, for calculating stator resistance value R according to stator resistance calculation formula_s；Wherein,

As the I_{s_abc}When being oriented in the d directions, the stator resistance calculation formula is $R_s=\frac{U_{s\_d}+{\mathrm{\ω}}_s{\mathrm{\ψ}}_{\mathrm{sq}}}{I_{s\_d}};$

As the I_{s_abc}When being oriented in the q directions, the stator resistance calculation formula is $R_s=\frac{U_{s\_q}-{\mathrm{\ω}}_s{\mathrm{\ψ}}_{\mathrm{sd}}}{I_{s\_q}}.$

Preferably, the stator magnetic linkage computing unit includes：

Magnetic linkage control ring set-point acquiring unit, for obtaining magnetic linkage control ring set-point ψ_{s_ref}And as the ψ_sAmplitude | ψ_s|；

Magnetic linkage component calculation unit, for utilizing formula ${\mathrm{\ψ}}_{\mathrm{sq}}=\sqrt{{{\mathrm{\ψ}}_{s\_\mathrm{ref}}}^2-{\left(\frac{U_{s\_q}}{{\mathrm{\ω}}_s}\right)}^2}$ Calculate the ψ_sq, utilize formula ${\mathrm{\ψ}}_{\mathrm{sd}}=\sqrt{{{\mathrm{\ψ}}_{s\_\mathrm{ref}}}^2-{\left(\frac{U_{s\_d}}{{\mathrm{\ω}}_s}\right)}^2}$ Calculate the ψ_sd。

Preferably, the temporary stable state discriminator includes：

Speed variable calculator, for calculating variation delta ω of the rotor speed of the motor in default time interval Δ T_r；

Hysteresis comparator, for judging the Δ ω_rWhether in default scope, if it is, the motor is in stable state, the sampling unit and the stator magnetic linkage computing unit are triggered.

Preferably, the default Δ T of the speed variable calculator is the time constant T of motor_r10 times.

Preferably, the default scope of the hysteresis comparator is interval [negative ring width, positive ring width].

It can be seen from above-mentioned technical scheme that, the present invention is by obtaining threephase stator electric current I during motor steady-state operation_{s_abc}, threephase stator voltage U_{s_abc}And stator magnetic linkage ψ_sEtc. parameter, by data processings such as Coordinate Conversions, obtain calculating the parameter value U needed for stator voltage_{s_d}、I_{s_d}、ω_sAnd ψ_sq, or, U_{s_q}、I_{s_q}、ω_sAnd ψ_sd, carry it into stator resistance calculation formula, you can obtain the numerical value of stator resistance.The calculating process of the embodiment of the present invention is only simple proportional integration, coordinate transform etc., and process is simple, and each parameter is obtained by accurately calculating, it is not necessary to the value of some parameter is determined by repetition test.Accordingly, with respect to existing stator resistance on-line identification method, on-line identification method provided in an embodiment of the present invention greatly reduces the complexity of identification process, improves identification efficiency.

Brief description of the drawings

Fig. 1 is the flow chart of stator resistance on-line identification method provided in an embodiment of the present invention；

Fig. 2 is the block diagram of electric current phaselocked loop in stator resistance on-line identification method provided in an embodiment of the present invention；

Fig. 3 is another flow chart of stator resistance on-line identification method provided in an embodiment of the present invention；

Fig. 4 is another block diagram of electric current phaselocked loop in stator resistance on-line identification method provided in an embodiment of the present invention；

Fig. 5 be stator resistance on-line identification method provided in an embodiment of the present invention in judge motor whether in stable state method flow diagram；

Fig. 6 is the structure chart of stator resistance on-line identification device provided in an embodiment of the present invention.

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, it is clear that described embodiment is only a part of embodiment of the invention, rather than whole embodiments.Based on the embodiment in the present invention, the every other embodiment that those of ordinary skill in the art are obtained under the premise of creative work is not made belongs to the scope of protection of the invention.

The embodiments of the invention provide a kind of stator resistance on-line identification method and device, to solve the problem of identification precision of the prior art is low, identification process is complicated.

Reference picture 1, stator resistance on-line identification method provided in an embodiment of the present invention, when stator current orientation is in synchronous rotary dq coordinate system d directions, including step：

S100：Judge whether motor is in stable state, if it is, performing step S101, otherwise perform step S100；

S101：Obtain threephase stator electric current I_{s_abc}With threephase stator voltage U_{s_abc}；

S102：By above-mentioned I_{s_abc}Synchronous rotary dq coordinate system d directions are oriented in, the component I in d directions is calculated_{s_d}；

I is obtained specifically, being calculated using equation below_{s_d}：

S103：Calculate lock phase angle theta_iWith synchronous rotational speed ω_s；

Step S102 and S103 can be realized by phaselocked loop.Fig. 2 shows a kind of block diagram of the phaselocked loop：

By I_{s_abc}It is oriented in by coordinate converter (abc/dq) 201 on d axles, that is, calculates I_{s_q}I when being zero_{s_d}Value；I_{s_d}Passing ratio integral controller (PI) 202 obtains ω_s；And then ω_sCalculated by integrator (1/s) 203 and obtain θ_i。

S104：According to above-mentioned θ_iCalculate U_{s_abc}Component U in synchronous rotary dq coordinate system d directions_{s_d}With the component U in q directions_{s_q}；

U is obtained specifically, being calculated using equation below_{s_d}And U_{s_q}：

S105：Obtain stator magnetic linkage ψ_s, calculate the ψ_sComponent ψ in the q directions_sq；

S106：According to stator resistance calculation formulaCalculate stator resistance value R_s。

The I that will be obtained in step S102~S105_{s_d}、U_{s_d}、ω_sAnd ψ_sqSubstitution above-mentioned formula $R_s=\frac{U_{s\_d}+{\mathrm{\ω}}_s{\mathrm{\ψ}}_{\mathrm{sq}}}{I_{s\_d}}$ In i.e. obtain stator resistance R_s。

The derivation of said stator resistance calculations formula is as follows.

General equation of the stator voltage of motor under rest frame be：

$u_s=i_s{R}_s+\frac{{\mathrm{d\ψ}}_s}{\mathrm{dt}}$ (formula 1)

In formula, u_sIt is stator voltage, i_sIt is stator current, R_sIt is stator resistance, ψ_sIt is stator magnetic linkage.

General equation of the stator voltage of motor under synchronous rotary dq coordinate systems be：

$\left\{\begin{array}{c}{u}_{\mathrm{sd}}=i_{\mathrm{sd}}{R}_s+\frac{d{\mathrm{\ψ}}_{\mathrm{sd}}}{\mathrm{dt}}-{\mathrm{\ω}}_s{\mathrm{\ψ}}_{\mathrm{sq}}\\ u_{\mathrm{sq}}=i_{\mathrm{sq}}{R}_s+\frac{{\mathrm{d\ψ}}_{\mathrm{sq}}}{\mathrm{dt}}+{\mathrm{\ω}}_s{\mathrm{\ψ}}_{\mathrm{sd}}\end{array}\right.$ (formula 2)

In formula, u_sd、u_sqFor generally stator voltage u_sThe component in d, q direction under synchronous rotary dq coordinate systems；i_sd、i_sqFor generally stator current i_sThe component in d, q direction under synchronous rotating frame；ψ_sd、ψ_sqFor stator magnetic linkage ψ_sThe component in d, q direction under synchronous rotating frame.

Work as I_{s_abc}When being oriented in the d directions of synchronous rotary dq coordinate systems, I_{s_q}=0.

On the premise of motor is in stable state, it can obtain by formula 2：

$\left\{\begin{array}{c}{u}_{\mathrm{sd}}=i_{\mathrm{sd}}{R}_s-{\mathrm{\ω}}_s{\mathrm{\ψ}}_{\mathrm{sq}}\\ u_{\mathrm{sq}}=i_{\mathrm{sq}}{R}_s+{\mathrm{\ω}}_s{\mathrm{\ψ}}_{\mathrm{sd}}\end{array}\right.$ (formula 3)

$\left\{\begin{array}{c}{i}_{\mathrm{sd}}=I_{s\_d}\\ i_{\mathrm{sq}}=I_{s\_q}=0\end{array}\right.$ (formula 4)

$\left\{\begin{array}{c}{u}_{\mathrm{sd}}=U_{s\_d}\\ u_{\mathrm{sq}}=U_{s\_q}\end{array}\right.$ (formula 5)

It can be derived from by formula 3~5：

${\mathrm{\ψ}}_{\mathrm{sd}}=\frac{U_{s\_q}}{{\mathrm{\ω}}_s}$ (formula 6)

And stator resistance calculation formula：

$R_s=\frac{U_{s\_d}+{\mathrm{\ω}}_s{\mathrm{\ψ}}_{\mathrm{sq}}}{I_{s\_d}}$ (formula 7).

Similarly, reference picture 3~4, when stator current orientation is in synchronous rotary dq coordinate system q directions, methods described of the embodiment of the present invention includes step：

S300：Judge whether motor is in stable state, if it is, performing step S301, otherwise re-execute step S300；

S301：Obtain threephase stator electric current I_{s_abc}With threephase stator voltage U_{s_abc}；

S302：By I_{s_abc}Synchronous rotary dq coordinate system q directions are oriented in, the component I in q directions is calculated_{s_q}；

S303：Calculate lock phase angle theta_iWith synchronous rotational speed ω_s；

S304：According to above-mentioned θ_iCalculate U_{s_abc}Component U in synchronous rotary dq coordinate system d directions_{s_d}With the component in q directions；

S305：Obtain stator magnetic linkage ψ_s, and calculate the ψ_sComponent ψ in the d directions_sd；

S306：According to stator resistance calculation formulaCalculate stator resistance value R_s。

In Fig. 4,401 be coordinate converter (abc/dq), and 402 be proportional and integral controller (PI), and 403 be integrator (1/s).

Above-mentioned calculating and derivation and stator current orientation are similar at d directions, will not be repeated here.

It can be seen from above-mentioned technical scheme that, the embodiment of the present invention is by obtaining threephase stator electric current I during motor steady-state operation_{s_abc}, threephase stator voltage U_{s_abc}And stator magnetic linkage ψ_sEtc. parameter, by data processings such as Coordinate Conversions, obtain calculating the parameter value U needed for stator voltage_{s_d}、I_{s_d}、ω_sAnd ψ_sq, or, U_{s_q}、I_{s_q}、ω_sAnd ψ_sd, substituted into stator resistance calculation formula, you can obtain the numerical value of stator resistance.The calculating process of the embodiment of the present invention is only simple proportional integration, coordinate transform etc., and process is simple, and each parameter is obtained by accurately calculating, it is not necessary to the value of some parameter is determined by repetition test.Accordingly, with respect to existing stator resistance on-line identification method, on-line identification method provided in an embodiment of the present invention greatly reduces the complexity of identification process, improves identification efficiency.

In other embodiments of the invention, the acquisition stator magnetic linkage ψ in above-described embodiment step S105 and S305_sAnd calculate respective component specific method include the following two kinds.

Method one：The estimation technique, i.e., estimate stator magnetic linkage ψ by its dependent variable (such as voltage, electric current)_sValue.Specifically, the embodiment of the present invention can use voltage model method.

The expression formula of voltage model is： $\left\{\begin{array}{c}{\mathrm{\ψ}}_{\mathrm{s\α}}=\∫(u_{\mathrm{s\α}}+i_{\mathrm{s\α}}{R}_s)\mathrm{dt}\\ {\mathrm{\ψ}}_{\mathrm{s\β}}=\∫(u_{\mathrm{s\β}}+i_{\mathrm{s\β}}{R}_s)\mathrm{dt}\end{array}\right.,$

ψ_sα、u_sα、i_sαRespectively ψ_s、u_s、i_sComponent in the orthogonal α β coordinate systems α directions of two-phase, ψ_sβ、u_sβ、i_sβRespectively ψ_s、u_s、i_sComponent in the orthogonal α β coordinate systems β directions of two-phase；

And then the direct two component ψ obtained by following changes in coordinates formula in synchronous rotary dq coordinate systems_sqAnd ψ_sd： $\left(\begin{array}{c}{\mathrm{\ψ}}_{\mathrm{sd}}\\ {\mathrm{\ψ}}_{\mathrm{sq}}\end{array}\right)=\left(\begin{array}{cc}{\cos \mathrm{\θ}}_r& {\sin \mathrm{\θ}}_r\\ {-\sin \mathrm{\θ}}_r& {\cos \mathrm{\θ}}_r\end{array}\right)\left(\begin{array}{c}{\mathrm{\ψ}}_{\mathrm{s\α}}\\ {\mathrm{\ψ}}_{\mathrm{s\β}}\end{array}\right).$

Method two：Fixed value method is taken, that is, obtains magnetic linkage control ring set-point ψ_{s_ref}Value be used as ψ_sAmplitude | ψ_s|。

The pace of change of stator magnetic linkage is much smaller than because the time constant of temperature change is much larger than the time constant that stator magnetic linkage changes, the i.e. pace of change of stator resistance, thus at a time, it is believed that stator magnetic linkage amplitude | ψ_s| it is constant, and in the calculating process of stator resistance, what is applied to is stator magnetic linkage amplitude | ψ_s|, therefore stator magnetic linkage amplitude | ψ_s| can value be magnetic linkage control ring flux linkage set value ψ_{s_ref}, i.e.,：|ψ_s|=ψ_{s_ref}。

Due to, $\left|{\mathrm{\ψ}}_s\right|=\sqrt{{{\mathrm{\ψ}}_{\mathrm{sd}}}^2+{{\mathrm{\ψ}}_{\mathrm{sq}}}^2},$ It therefore, it can obtain：

${\mathrm{\ψ}}_{\mathrm{sq}}=\sqrt{{{\mathrm{\ψ}}^2}_{s\_\mathrm{ref}}-{{\mathrm{\ψ}}^2}_{\mathrm{sd}}}$ (formula 8)

With reference to formula 6 and 8, obtain calculating ψ_sqFormula：

${\mathrm{\ψ}}_{\mathrm{sq}}=\sqrt{{{\mathrm{\ψ}}_{s\_\mathrm{ref}}}^2-{\left(\frac{U_{s\_q}}{{\mathrm{\ω}}_s}\right)}^2}$ (formula 9)

Formula 7 can further be derived by formula 9：

$R_s=\frac{U_{s\_d}+{\mathrm{\ω}}_s{\mathrm{\ψ}}_{\mathrm{sq}}}{I_{s\_d}}=\frac{U_{s\_d}+{\mathrm{\ω}}_s\sqrt{{{\mathrm{\ψ}}_{s\_\mathrm{ref}}}^2-{\left(\frac{U_{s\_q}}{{\mathrm{\ω}}_s}\right)}^2}}{I_{s\_d}}.$

Equally, ψ is calculated_sdSpecially：Utilize formulaCalculate ψ_sd, formula $R_s=\frac{U_{s\_q}-{\mathrm{\ω}}_s{\mathrm{\ψ}}_{\mathrm{sd}}}{I_{s\_q}}$ Can further it be derived as：

$R_s=\frac{U_{s\_q}-{\mathrm{\ω}}_s{\mathrm{\ψ}}_{\mathrm{sd}}}{I_{s\_q}}=\frac{U_{s\_q}-{\mathrm{\ω}}_s\sqrt{{{\mathrm{\ψ}}_{s\_\mathrm{ref}}}^2-{\left(\frac{U_{s\_d}}{{\mathrm{\ω}}_s}\right)}^2}}{I_{s\_q}}.$

Relative to prior art, the above embodiment of the present invention is by taking fixed value method directly to take the flux linkage set value ψ of magnetic linkage control ring_{s_ref}For the amplitude of stator magnetic linkage | ψ_s|, and then obtain ψ_sdAnd ψ_sq, the estimation to stator magnetic linkage, rotor flux is eliminated, the complexity of identification process is reduce further, the accuracy of identification is improved.

In other embodiments of the invention, the acquisition threephase stator electric current I in above-described embodiment_{s_abc}, threephase stator voltage U_{s_abc}Embodiment include：

Obtain the output valve I of the current sensor matched with the rated current of motor_{s_abc}；

Obtain the output valve U of the voltage sensor matched with the rated voltage of motor_{s_abc}。

Above-mentioned current sensor and voltage sensor ensure that I_{s_abc}And U_{s_abc}Possesses higher accuracy.

In addition, stator voltage can also be obtained by way of voltage reconstruction.

In other embodiments of the invention, whether the embodiment in stable state includes the motor that judges in above-described embodiment step S100 and S300：

Calculate total variation Δ ω of the rotor speed of motor in default time interval Δ T_r；

Judge Δ ω_rWhether in default scope, if it is, motor is in stable state.

Where it is assumed that the time constant of motor is T_r, then above-mentioned default time interval Δ T can use 10T_r。

Theoretically, when motor is in stable state, there should be Δ ω_r=0；But in practical application, above-mentioned stable state is extremely difficult to, therefore it need to only work as Δ ω_rWhen in a certain minimum scope, i.e., default scope, you can think that motor is in stable state.Specifically, can select hysteresis comparator judges Δ ω_rWhether in default scope, now, above-mentioned default scope is desirable interval [negative ring width, positive ring width], as Δ ω_rOutside the interval, i.e. Δ ω_rAbsolute value be more than hysteresis comparator ring width when, motor be in unstable state；As Δ ω_rWithin the interval, i.e. Δ ω_rAbsolute value be less than ring width when, motor be in stable state.

The ring width of hysteresis comparator can weigh selection according to the rotary inertia of motor, and such as ring width elects 5 as, then above-mentioned default scope is [- 5 ,+5].

Fig. 5 shows that the above embodiment of the present invention judges whether motor is in a kind of embodiment of stable state.

S501：Timer is reset, and current time is designated as T (k₁), rotor speed is ω_r(k₁) start timing；

S502：Current time is designated as T (k₂), rotor speed is ω_r(k₂), calculate Δ T=T (k₂)-T(k₁), Δ ω_r=ω_r(k₂)-ω_r(k₁)；

S503：Judge whether Δ T is equal to 10T_r, if it is, into step S504, otherwise return to step S502；

S504：Judge Δ ω_rWhether meet | Δ ω_r|≤5, if it is, motor, which is in stable state, enters step S101 or S301, otherwise return to step S502.

Reference picture 6, the embodiment of the present invention additionally provides a kind of stator resistance on-line identification device, including：Stable state discriminator 601, sampling unit 602, stator current phaselocked loop 603, stator voltage coordinate transformation unit 604, stator magnetic linkage computing unit 605 and stator resistance on-line identification unit 606；Wherein,

Temporary stable state discriminator 601, for judging whether motor is in stable state, if it is, triggering the sampling unit 602 and stator magnetic linkage computing unit 605；

Sampling unit 602, for obtaining threephase stator electric current I_{s_abc}With threephase stator voltage U_{s_abc}；

Stator current phaselocked loop 603, for by above-mentioned I_{s_abc}Synchronous rotary dq coordinate system d directions are oriented in, the component I in q directions is calculated_{s_q}, or, by above-mentioned I_{s_abc}Synchronous rotary dq coordinate system q directions are oriented in, the component I in d directions is calculated_{s_d}, and calculate lock phase angle theta_iWith synchronous rotational speed ω_s；

Stator voltage coordinate transformation unit 604, for according to above-mentioned θ_iCalculate U_{s_abc}Component U in rotating coordinate system d directions_{s_d}With the component U in q directions_{s_q}；

Stator magnetic linkage computing unit 605, for obtaining stator magnetic linkage ψ_s, and work as I_{s_abc}When being oriented in d directions, ψ is calculated_sComponent ψ in q directions_sq, work as I_{s_abc}When being oriented in q directions, ψ is calculated_sComponent ψ in d directions_sd；

Stator resistance on-line identification unit 606, stator resistance value R is calculated according to stator resistance calculation formula_s；Wherein, I is worked as_{s_abc}When being oriented in synchronous rotary dq coordinate system d directions, said stator resistance calculations formula isWork as I_{s_abc}When being oriented in synchronous rotary dq coordinate system q directions, said stator resistance

Calculation formula is $R_s=\frac{U_{s\_q}-{\mathrm{\ω}}_s{\mathrm{\ψ}}_{\mathrm{sd}}}{I_{s\_q}}.$

Specifically, sampling unit 602 includes：

Voltage sampling unit, the output valve U for obtaining the voltage sensor matched with the rated voltage of motor_{s_abc}；

Current sampling unit, the output valve I for obtaining the current sensor matched with the rated current of motor_{s_abc}。

Further, the stator magnetic linkage computing unit 605 in above-described embodiment includes：

Magnetic linkage control ring set-point acquiring unit, for obtaining magnetic linkage control ring set-point ψ_{s_ref}And as the ψ_sAmplitude | ψ_s|；

Magnetic linkage component calculation unit, for utilizing formulaCalculate ψ_sq, utilize formula ${\mathrm{\ψ}}_{\mathrm{sd}}=\sqrt{{{\mathrm{\ψ}}_{s\_\mathrm{ref}}}^2-{\left(\frac{U_{s\_d}}{{\mathrm{\ω}}_s}\right)}^2}$ Calculate ψ_sd。

Further, the temporary stable state discriminator 601 in above-described embodiment includes：

Speed variable calculator, for calculating variation delta ω of the rotor speed of the motor in default time interval Δ T_r

Hysteresis comparator, for judging the Δ ω_rWhether in default scope, if it is, motor be in stable state, triggering sampling unit 602 and with stator magnetic linkage computing unit 605.

Wherein, it is above-mentioned default to may range from interval [negative ring width, positive ring width].

The foregoing description of the disclosed embodiments, enables professional and technical personnel in the field to realize or using the present invention.A variety of modifications to these embodiments be will be apparent for those skilled in the art, and generic principles defined herein can be realized in other embodiments without departing from the spirit or scope of the present invention.Therefore, the present invention is not intended to be limited to the embodiments shown herein, and is to fit to the most wide scope consistent with features of novelty with principles disclosed herein.

Claims (8)

1. a kind of stator resistance on-line identification method, it is characterised in that including：

Judge whether motor is in stable state, if it is, obtaining threephase stator electric current I_{s_abc}With threephase stator voltage U_{s_abc}；

By the I_{s_abc}The d directions of synchronous rotary dq coordinate systems are oriented in, the component I in the d directions is calculated_{s_d}, or, by the I_{s_abc}Synchronous rotary dq coordinate system q directions are oriented in, the component I in the q directions is calculated_{s_q}；

Calculate lock phase angle theta_i, synchronous rotational speed ω_s；

According to the θ_iCalculate the U_{s_abc}Component U in the d directions_{s_d}With the component U in the q directions_{s_q}；

Obtain stator magnetic linkage ψ_s, and as the I_{s_abc}When being oriented in the d directions, the ψ is calculated_sComponent ψ in the q directions_sq, as the I_{s_abc}When being oriented in the q directions, the ψ is calculated_sComponent ψ in the d directions_sd；

Stator resistance value R is calculated according to stator resistance calculation formula_s；Wherein,

As the I_{s_abc}When being oriented in the d directions, the stator resistance calculation formula is

As the I_{s_abc}When being oriented in the q directions, the stator resistance calculation formula is

Wherein,

By I_{s_abc}It is oriented in by coordinate converter abc/dq on d axles, that is, calculates I_{s_q}I when being zero_{s_d}Value, or, by I_{s_abc}It is oriented in by coordinate converter abc/dq on q axles, that is, calculates I_{s_d}I when being zero_{s_q}Value；

I_{s_d}Or I_{s_q}Passing ratio integral controller (PI) obtains ω_s；

By ω_sCalculated by integrator (1/s) and obtain θ_i；

The acquisition stator magnetic linkage includes：

Component ψ of the stator magnetic linkage in orthogonal α β coordinate systems α, β directions of two-phase is calculated respectively_sα、ψ_sβ, the formula specifically used for,ψ_sα、u_sα、i_sαRespectively ψ_s、u_s、i_sComponent in the orthogonal α β coordinate systems α directions of two-phase, ψ_sβ、u_sβ、i_sβRespectively ψ_s、u_s、i_sComponent in the orthogonal α β coordinate systems β directions of two-phase；u_sIt is stator voltage, i_sIt is stator current；

Two component ψ in synchronous rotary dq coordinate systems are obtained by changes in coordinates formula_sqAnd ψ_sd, the formula specifically used for

2. according to the method described in claim 1, it is characterised in that described to judge whether motor specifically includes in stable state：

Calculate variation delta ω of the rotor speed of the motor in default time interval Δ T_r；

Judge the Δ ω_rWhether in default scope, if it is, the motor is in stable state.

3. method according to claim 2, it is characterised in that the Δ T is set as the time constant T of motor_r10 times.

4. method according to claim 2, it is characterised in that the judgement Δ ω_rWhether include in default scope：Judge the Δ ω using hysteresis comparator_rWhether in default scope；

The default scope is interval [negative ring width, positive ring width].

5. a kind of stator resistance on-line identification device, it is characterised in that including temporary stable state discriminator, sampling unit, stator current phaselocked loop, stator voltage coordinate transformation unit, stator magnetic linkage computing unit and stator resistance on-line identification unit；Wherein,

The temporary stable state discriminator, for judging whether motor is in stable state, if it is, triggering the sampling unit and the stator magnetic linkage computing unit；

The sampling unit, for obtaining threephase stator electric current I_{s_abc}With threephase stator voltage U_{s_abc}；

The stator current phaselocked loop, for by the I_{s_abc}Synchronous rotary dq coordinate system d directions are oriented in, the component I in d directions is calculated_{s_d}, or, by the I_{s_abc}Synchronous rotary dq coordinate system q directions are oriented in, the component I in q directions is calculated_{s_q}, and calculate lock phase angle theta_iWith synchronous rotational speed ω_s；

The stator voltage coordinate transformation unit, for calculating obtained θ according to the stator current phaselocked loop_iCalculate the U_{s_abc}Component U in the d directions_{s_d}With the component U in the q directions_{s_q}；

The stator magnetic linkage computing unit, for obtaining stator magnetic linkage ψ_s, and as the I_{s_abc}When being oriented in the d directions, the ψ is calculated_sComponent ψ in the q directions_sq, as the I_{s_abc}When being oriented in the q directions, the ψ is calculated_sComponent ψ in the d directions_sd；

The stator resistance on-line identification unit, for calculating stator resistance value R according to stator resistance calculation formula_s；Wherein,

As the I_{s_abc}When being oriented in the d directions, the stator resistance calculation formula is

As the I_{s_abc}When being oriented in the q directions, the stator resistance calculation formula is

Wherein,

By I_{s_abc}It is oriented in by coordinate converter abc/dq on d axles, that is, calculates I_{s_q}I when being zero_{s_d}Value, or, by I_{s_abc}It is oriented in by coordinate converter abc/dq on q axles, that is, calculates I_{s_d}I when being zero_{s_q}Value；

I_{s_d}Or I_{s_q}Passing ratio integral controller (PI) obtains ω_s；

By ω_sCalculated by integrator (1/s) and obtain θ_i；

The acquisition stator magnetic linkage includes：

Component ψ of the stator magnetic linkage in orthogonal α β coordinate systems α, β directions of two-phase is calculated respectively_sα、ψ_sβ, the formula specifically used for,ψ_sα、u_sα、i_sαRespectively ψ_s、u_s、i_sComponent in the orthogonal α β coordinate systems α directions of two-phase, ψ_sβ、u_sβ、i_sβRespectively ψ_s、u_s、i_sComponent in the orthogonal α β coordinate systems β directions of two-phase；u_sIt is stator voltage, i_sIt is stator current；

Two component ψ in synchronous rotary dq coordinate systems are obtained by changes in coordinates formula_sqAnd ψ_sd, the formula specifically used for

6. device according to claim 5, it is characterised in that the temporary stable state discriminator includes：

Speed variable calculator, for calculating variation delta ω of the rotor speed of the motor in default time interval Δ T_r；

Hysteresis comparator, for judging the Δ ω_rWhether in default scope, if it is, the motor is in stable state, the sampling unit and the stator magnetic linkage computing unit are triggered.

7. device according to claim 6, it is characterised in that the default Δ T of speed variable calculator is the time constant T of motor_r10 times.

8. device according to claim 6, it is characterised in that the default scope of hysteresis comparator is interval [negative ring width, positive ring width].