CN104836507A - Permanent magnet synchronous motor d-axis and q-axis induction parameter off-line identification method and system - Google Patents

Abstract

The invention discloses a permanent magnet synchronous motor d-axis and q-axis induction parameter off-line identification method and a system. The method comprises controlling a permanent magnet synchronous motor to be still and a winding current of the permanent magnet synchronous motor to be zero, respectively loading a first voltage vector V-<arrow>(100), a second voltage vector V<rightarrow>(010) and a third voltage vector V<rightarrow>(001), sampling currents of the permanent magnet synchronous motor respectively under the actions of the first voltage vector V<rightarrow>(100), the second voltage vector V<rightarrow>(010) and the third voltage vector V<rightarrow>(001), calculating to obtain a first current variable I<1> and a second current variable I<2>, and calculating to obtain a q-axis induction parameter L<q> and a d-axis induction parameter L<d> of the permanent magnet synchronous motor according to a DC bus voltage u<dc>, the first current variable I<1> and a second current variable I<2>. The calculated amount of the method is small, and the problem of the large calculated amount in existing permanent magnet synchronous motor parameter off-line identification and the problem of difficult implementation are effectively solved.

Description

Permagnetic synchronous motor cross, straight axle inductance parameters offline identification method and system

Technical field

The present invention relates to machine field, particularly relate to a kind of permagnetic synchronous motor cross, straight axle inductance parameters offline identification method and system.

Background technology

Permagnetic synchronous motor (Permanent Magnet Synchronous Motor, PMSM), so that its structure is simple, reliable, volume is little, loss is low, efficiency advantages of higher, is used widely in Digit Control Machine Tool, electric field.Permagnetic synchronous motor parameter has important impact for its application.The off-line identification of permagnetic synchronous motor parameter is mainly by before permagnetic synchronous motor operation, control inverter applies multi-form voltage to permagnetic synchronous motor winding, current excitation, detect the electric current and voltage exciter response of permagnetic synchronous motor, and according to the relation between exciter response and the parameter of electric machine, calculate corresponding permagnetic synchronous motor parameter, or adopt certain fitting algorithm identification permagnetic synchronous motor parameter: adopt pulse voltage ballistic method to need the method by applying direct current to obtain the d axle (rotor magnetic pole axle) of permagnetic synchronous motor, if the axle of permagnetic synchronous motor cannot rotate, such as be with band-type brake machinery, then cannot obtain the d axle of permagnetic synchronous motor, and the high frequency voltage of one group of three-phase equilibrium or current signal are applied on permagnetic synchronous motor by employing, the feedback high-frequency current of sampling permagnetic synchronous motor or voltage, calculate the quadrature axis inductance parameters L of permagnetic synchronous motor according to the amplitude of the curtage of feedback _q, and the d-axis inductance parameters L of permagnetic synchronous motor _d, amount of calculation is large, not easily realizes.

Summary of the invention

Based on this, be necessary for the amount of calculation in the off-line identification of existing permagnetic synchronous motor parameter large, the problem not easily realized, provides a kind of permagnetic synchronous motor cross, straight axle inductance parameters offline identification method and system.

A kind of permagnetic synchronous motor cross, straight axle inductance parameters offline identification method, comprises the steps:

Controlling permagnetic synchronous motor winding current that is static and described permagnetic synchronous motor is zero, and in conduction inverter, the lower brachium pontis of brachium pontis, V phase and W phase in U phase, disconnects U phase in described inverter lower brachium pontis, V phase and brachium pontis in W phase, at α _uβ _uunder coordinate system, it is the first preset time t that the winding to described permagnetic synchronous motor loads duration ₁the first voltage vector

The lower brachium pontis of brachium pontis, U phase and W phase in V phase in inverter described in conducting, disconnects V phase in described inverter lower brachium pontis, U phase and brachium pontis in W phase, at α _vβ _vunder coordinate system, it is the second preset time t that the winding to described permagnetic synchronous motor loads duration ₂the second voltage vector

The lower brachium pontis of brachium pontis, U phase and V phase in W phase in inverter described in conducting, disconnects W phase in described inverter lower brachium pontis, U phase and brachium pontis in V phase, at α _wβ _wunder coordinate system, it is the 3rd preset time t that the winding to described permagnetic synchronous motor loads duration ₃tertiary voltage vector

Detect DC bus-bar voltage u _dc, and sample described permagnetic synchronous motor respectively at described first voltage vector described second voltage vector with described tertiary voltage vector electric current under effect, and calculate the first current variable I ₁with the second current variable I ₂;

According to described DC bus-bar voltage u _dc, described first current variable I ₁with described second current variable I ₂, calculate the quadrature axis inductance parameters L of described permagnetic synchronous motor _q, and the d-axis inductance parameters L of described permagnetic synchronous motor _d;

Wherein, described first preset time t ₁, described second preset time t ₂with described 3rd preset time t ₃all be less than d axle time constant and be less than q axle time constant r _sfor the phase resistance parameter of described permagnetic synchronous motor.

What deserves to be explained is, described second voltage vector direction is described first voltage vector in advance 120 °, direction, described tertiary voltage vector direction is described second voltage vector in advance 120 °, direction;

α _uaxle is described permagnetic synchronous motor U phase direction, β _uaxle is the advanced U phase of described permagnetic synchronous motor 90 ° of directions; α _vaxle is described permagnetic synchronous motor V phase direction, β _vaxle is the advanced V phase of described permagnetic synchronous motor 90 ° of directions; α _waxle is described permagnetic synchronous motor W phase direction, β _wthe advanced W phase of permagnetic synchronous motor described in axle 90 ° of directions.

Preferably, described first preset time t ₁, described second preset time t ₂with described 3rd preset time t ₃equal, and value is t.

As a kind of embodiment, the described permagnetic synchronous motor of described sampling is respectively at described first voltage vector described second voltage vector with described tertiary voltage vector electric current under effect, and calculate the first current variable I ₁with the second current variable I ₂, comprise the steps:

Sample described permagnetic synchronous motor respectively at described second voltage vector with described tertiary voltage vector under effect, the first current i of generation _v(t) and the second current i _w(t);

To described first current i _v(t) and described second current i _wt () carries out Clarke conversion respectively, obtain described first current i _vt () is at described α _vβ _vexpression i under coordinate system _v(t)=[i _{α v}(t), i _{β v}(t)] ^t, and described second current i _wt () is at described α _wβ _wexpression i under coordinate system _w(t)=[i _{α w}(t), i _{β w}(t)] ^t;

Respectively to described first current i _vt () is at described α _vβ _vexpression i under coordinate system _v(t)=[i _{α v}(t), i _{β v}(t)] ^t, and described second current i _wt () is at described α _wβ _wexpression i under coordinate system _w(t)=[i _{α w}(t), i _{β w}(t)] ^tcarry out current transformation, obtain

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;v}}\left(t\right)\\ i_{\mathrm{\&beta;v}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2({\mathrm{\&theta;}}_r-\frac{2}{3}\mathrm{\&pi;})\\ I_2\sin 2({\mathrm{\&theta;}}_r-\frac{2}{3}\mathrm{\&pi;})\end{array}\right];$

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;w}}\left(t\right)\\ i_{\mathrm{\&beta;w}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2({\mathrm{\&theta;}}_r+\frac{2}{3}\mathrm{\&pi;})\\ I_2\sin 2({\mathrm{\&theta;}}_r+\frac{2}{3}\mathrm{\&pi;})\end{array}\right].$

As a kind of embodiment, described according to described DC bus-bar voltage u _dc, described first current variable I ₁with described second current variable I ₂, calculate the quadrature axis inductance parameters L of described permagnetic synchronous motor _q, and the d-axis inductance parameters L of described permagnetic synchronous motor _d, comprise the steps:

According to formula:

$\left\{\begin{array}{c}{L}_d=\frac{2}{3}\frac{u_{\mathrm{dc}}t}{I_1+I_2}\\ L_q=\frac{2}{3}\frac{u_{\mathrm{dc}}t}{I_1-I_2}\end{array}\right.$

Calculate the quadrature axis inductance parameters L of described permagnetic synchronous motor _q, and the d-axis inductance parameters L of described permagnetic synchronous motor _d.

Accordingly, for realizing above-mentioned permagnetic synchronous motor cross, straight axle inductance parameters offline identification method, present invention also offers a kind of permagnetic synchronous motor cross, straight axle inductance parameters off-line identification system, comprise pulse signal generator, inverter, Clarke converter unit, current transformation unit, control unit and inductance computing unit, wherein:

The output of described pulse signal generator is connected with the input of described inverter, and the output of described inverter is connected with the input of permagnetic synchronous motor;

Described control unit comprises the first control subelement, second and controls subelement, the 3rd control subelement and the first detection sub-unit, wherein:

Described first controls subelement, be zero for controlling described permagnetic synchronous motor winding current that is static and described permagnetic synchronous motor, the lower brachium pontis of brachium pontis, V phase and W phase in U phase in conduction inverter, disconnects U phase in described inverter lower brachium pontis, V phase and brachium pontis in W phase, at α _uβ _uunder coordinate system, control winding from described pulse signal generator to described permagnetic synchronous motor load duration be the first preset time t ₁the first voltage vector

Described second controls subelement, for the lower brachium pontis of brachium pontis, U phase and W phase in V phase in inverter described in conducting, disconnects V phase in described inverter lower brachium pontis, U phase and brachium pontis in W phase, at α _vβ _vunder coordinate system, control winding from described pulse signal generator to described permagnetic synchronous motor load duration be the second preset time t ₂the second voltage vector

Described 3rd controls subelement, for the lower brachium pontis of brachium pontis, U phase and V phase in W phase in inverter described in conducting, disconnects W phase in described inverter lower brachium pontis, U phase and brachium pontis in V phase, at α _wβ _wunder coordinate system, control winding from described pulse signal generator to described permagnetic synchronous motor load duration be the 3rd preset time t ₃tertiary voltage vector

Described first detection sub-unit, for detecting DC bus-bar voltage u _dc;

Described Clarke converter unit, for sampling described permagnetic synchronous motor respectively at described first voltage vector described second voltage vector with described tertiary voltage vector electric current under effect, and carry out Clarke conversion;

Described current transformation unit, carries out the described permagnetic synchronous motor after described Clarke conversion at described first voltage vector for basis described second voltage vector with described tertiary voltage vector electric current under effect, calculates the first current variable I ₁with the second current variable I ₂;

Described inductance computing unit, for according to described DC bus-bar voltage u _dc, described first current variable I ₁with described second current variable I ₂, calculate the quadrature axis inductance parameters L of described permagnetic synchronous motor _q, and the d-axis inductance parameters L of described permagnetic synchronous motor _d;

Wherein, described first preset time t ₁, described second preset time t ₂with described 3rd preset time t ₃all be less than d axle time constant and be less than q axle time constant r _sfor the phase resistance parameter of described permagnetic synchronous motor.

What deserves to be explained is, described second voltage vector direction is described first voltage vector in advance 120 °, direction, described tertiary voltage vector direction is described second voltage vector in advance 120 °, direction;

α _uaxle is described permagnetic synchronous motor U phase direction, β _uaxle is the advanced U phase of described permagnetic synchronous motor 90 ° of directions; α _vaxle is described permagnetic synchronous motor V phase direction, β _vaxle is the advanced V phase of described permagnetic synchronous motor 90 ° of directions; α _waxle is described permagnetic synchronous motor W phase direction, β _waxle is the advanced W phase of described permagnetic synchronous motor 90 ° of directions.

Preferably, described first preset time t ₁, described second preset time t ₂with described 3rd preset time t ₃equal, and value is t.

Preferably, described Clarke converter unit comprises the first sampling subelement and the first varitron unit, and described current transformation unit comprises the second varitron unit and the 3rd varitron unit, wherein:

Described first sampling subelement, for sampling described permagnetic synchronous motor respectively at described second voltage vector with described tertiary voltage vector under effect, the first current i of generation _v(t) and the second current i _w(t);

Described first varitron unit, for described first current i _v(t) and described second current i _wt () carries out Clarke conversion respectively, obtain described first current i _vt () is at described α _vβ _vexpression i under coordinate system _v(t)=[i _{α v}(t), i _{β v}(t)] ^t, and described second current i _wt () is at described α _wβ _wexpression i under coordinate system _w(t)=[i _{α w}(t), i _{β w}(t)] ^t;

Described second varitron unit, for described first current i _vt () is at described α _vβ _vexpression i under coordinate system _v(t)=[i _{α v}(t), i _{β v}(t)] ^tcarry out current transformation, obtain:

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;v}}\left(t\right)\\ i_{\mathrm{\&beta;v}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2({\mathrm{\&theta;}}_r-\frac{2}{3}\mathrm{\&pi;})\\ I_2\sin 2({\mathrm{\&theta;}}_r-\frac{2}{3}\mathrm{\&pi;})\end{array}\right];$

Described 3rd varitron unit, for described second current i _wt () is at described α _wβ _wexpression i under coordinate system _w(t)=[i _{α w}(t), i _{β w}(t)] ^tcarry out current transformation, obtain:

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;w}}\left(t\right)\\ i_{\mathrm{\&beta;w}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2({\mathrm{\&theta;}}_r+\frac{2}{3}\mathrm{\&pi;})\\ I_2\sin 2({\mathrm{\&theta;}}_r+\frac{2}{3}\mathrm{\&pi;})\end{array}\right].$

As a kind of embodiment, described inductance computing unit, for according to formula:

$\left\{\begin{array}{c}{L}_d=\frac{2}{3}\frac{u_{\mathrm{dc}}t}{I_1+I_2}\\ L_q=\frac{2}{3}\frac{u_{\mathrm{dc}}t}{I_1-I_2}\end{array}\right.$

Calculate the quadrature axis inductance parameters L of described permagnetic synchronous motor _q, and the d-axis inductance parameters L of described permagnetic synchronous motor _d.

A kind of permagnetic synchronous motor cross, straight axle inductance parameters offline identification method provided by the invention and system, by applying different voltage vectors to permagnetic synchronous motor, by detecting the electric current of permagnetic synchronous motor under different voltage vector effects, and the electric current of permagnetic synchronous motor under different voltage vector effects is converted, obtain for calculating permagnetic synchronous motor quadrature axis inductance parameters L _qwith d-axis inductance parameters L _dthe first current variable I ₁with the second current variable I ₂, and according to the first current variable I ₁with the second current variable I ₂calculate the quadrature axis inductance parameters L of permagnetic synchronous motor _qwith d-axis inductance parameters L _d, it fixes the rotating shaft of permagnetic synchronous motor without the need to external equipment, is easy to realize, and amount of calculation is little, and accuracy is high, and the amount of calculation effectively solved in the off-line identification of existing permagnetic synchronous motor parameter is large, the problem not easily realized.

Accompanying drawing explanation

Fig. 1 is permagnetic synchronous motor cross, straight axle inductance parameters offline identification method one specific embodiment flow chart;

Fig. 2 is permagnetic synchronous motor cross, straight axle inductance parameters off-line identification system one specific embodiment schematic diagram;

Fig. 3 is the another specific embodiment schematic diagram of permagnetic synchronous motor cross, straight axle inductance parameters off-line identification system.

Embodiment

For making technical solution of the present invention clearly, below in conjunction with drawings and the specific embodiments, the present invention is described in further details.

See Fig. 1, as a specific embodiment of permagnetic synchronous motor of the present invention cross, straight axle inductance parameters offline identification method, comprise the steps:

S100, controlling permagnetic synchronous motor winding current that is static and permagnetic synchronous motor is zero, and in conduction inverter, the lower brachium pontis of brachium pontis, V phase and W phase in U phase, disconnects U phase in inverter lower brachium pontis, V phase and brachium pontis in W phase, at α _uβ _uunder coordinate system, it is the first preset time t that the winding to permagnetic synchronous motor loads duration ₁the first voltage vector , detect and obtain DC bus-bar voltage u _dc;

S200, the lower brachium pontis of brachium pontis, U phase and W phase in V phase in conduction inverter, disconnects V phase in inverter lower brachium pontis, U phase and brachium pontis in W phase, at α _vβ _vunder coordinate system, it is the second preset time t that the winding to permagnetic synchronous motor loads duration ₂the second voltage vector

S300, the lower brachium pontis of brachium pontis, U phase and V phase in W phase in conduction inverter, disconnects W phase in inverter lower brachium pontis, U phase and brachium pontis in V phase, at α _wβ _wunder coordinate system, it is the 3rd preset time t that the winding to permagnetic synchronous motor loads duration ₃tertiary voltage vector

S400, sampling permagnetic synchronous motor is respectively at the first voltage vector second voltage vector with tertiary voltage vector electric current under effect, and calculate the first current variable I ₁with the second current variable I ₂;

S500, according to DC bus-bar voltage u _dc, the first current variable I ₁with the second current variable I ₂, calculate the quadrature axis inductance parameters L of permagnetic synchronous motor _q, and the d-axis inductance parameters L of permagnetic synchronous motor _d;

Wherein, the first preset time t ₁, the second preset time t ₂with the 3rd preset time t ₃all be less than d axle time constant and be less than q axle time constant r _sfor the phase resistance parameter of permagnetic synchronous motor.

One specific embodiment of permagnetic synchronous motor provided by the invention cross, straight axle inductance parameters offline identification method, first at α _uβ _uunder coordinate system, loading duration to permagnetic synchronous motor is the first preset time t ₁the first voltage vector detection obtains DC bus-bar voltage u _dc; And control permagnetic synchronous motor continue winding current that is static and permagnetic synchronous motor be zero, at α _vβ _vloading duration to permagnetic synchronous motor under coordinate system is the second preset time t ₂the second voltage vector at α _wβ _wloading duration to permagnetic synchronous motor under coordinate system is the 3rd preset time t ₃tertiary voltage vector sampling permagnetic synchronous motor is respectively at the first voltage vector second voltage vector with tertiary voltage vector electric current under effect, and calculate the first current variable I ₁with the second current variable I ₂; According to DC bus-bar voltage u _dc, the first current variable I ₁with the second current variable I ₂, calculate the quadrature axis inductance parameters L of permagnetic synchronous motor _q, and the d-axis inductance parameters L of permagnetic synchronous motor _d; Its rotating shaft not needing external equipment to fix permagnetic synchronous motor can realize the quadrature axis inductance parameters L of permagnetic synchronous motor _q, and d-axis inductance parameters L _didentification, method is easy, is easy to realize, and amount of calculation is little, and the amount of calculation effectively solved in the off-line identification of existing permagnetic synchronous motor parameter is large, the problem not easily realized.

At this, it should be noted that, in permagnetic synchronous motor provided by the invention cross, straight axle inductance parameters offline identification method, the first voltage vector that the winding respectively to permagnetic synchronous motor loads second voltage vector with tertiary voltage vector sequencing can mutually exchange, as long as the voltage vector loaded to permagnetic synchronous motor is corresponding with coordinate system, time simultaneously to each phase on-load voltage vector of permagnetic synchronous motor, the upper brachium pontis of corresponding each phase of permagnetic synchronous motor in control inverter and lower brachium pontis is all needed to carry out identical switch process.

In addition, the first preset time t ₁, the second preset time t ₂with the 3rd preset time t ₃value can be identical, also can be different, as long as it is all less than d axle time constant and be less than q axle time constant , preferably, the first preset time t in the specific embodiment of permagnetic synchronous motor provided by the invention cross, straight axle inductance parameters offline identification method ₁, the second preset time t ₂with the 3rd preset time t ₃equal, and value is t.

Wherein, the second voltage vector advanced first voltage vector in direction 120 °, direction, tertiary voltage vector advanced second voltage vector in direction 120 °, direction;

α _uaxle is permagnetic synchronous motor U phase direction, β _uaxle is the advanced U phase of permagnetic synchronous motor 90 ° of directions; α _vaxle is permagnetic synchronous motor V phase direction, β _vaxle is the advanced V phase of permagnetic synchronous motor 90 ° of directions; α _waxle is permagnetic synchronous motor W phase direction, β _waxle is the advanced W phase of permagnetic synchronous motor 90 ° of directions.

In the cross, straight axle inductance parameters test of permagnetic synchronous motor, need to apply pulsed voltage excitation to permagnetic synchronous motor, the current response produced under pulsed voltage excitation by detecting permagnetic synchronous motor calculates the cross, straight axle inductance parameters of permagnetic synchronous motor.Applying to permagnetic synchronous motor in the process of pulsed voltage excitation, controlling permagnetic synchronous motor and remain static, therefore, the now angular rate ω of permagnetic synchronous motor _r=p θ _r=0, as a kind of embodiment, brachium pontis in U phase, the lower brachium pontis of V phase and the lower equal conducting of brachium pontis of W phase in control inverter, in control inverter, in the lower brachium pontis of U phase, the upper brachium pontis of V phase and W phase, brachium pontis all disconnects simultaneously, thus realization is at α _uβ _uunder coordinate system, apply the first voltage vector to permagnetic synchronous motor , now detect and obtain permagnetic synchronous motor at the first voltage vector voltage drive response under effect is $\left[\begin{array}{c}{u}_{\mathrm{\&alpha;u}}\\ u_{\mathrm{\&beta;u}}\end{array}\right]=\frac{2}{3}\left[\begin{array}{c}{u}_{\mathrm{dc}}\\ 0\end{array}\right],$ Wherein, u _dcfor DC bus-bar voltage; Vow owing to applying the first voltage to permagnetic synchronous motor duration be the first preset time t ₁, and, the first preset time t ₁be less than d axle time constant and be less than q axle time constant therefore, when the cross, straight axle inductance parameters of identification permagnetic synchronous motor, the phase resistance parameter R of permagnetic synchronous motor can be ignored _simpact, thus, permagnetic synchronous motor is at α _uβ _umathematical Modeling (i.e. voltage equation) under coordinate system can be changed into:

$\begin{array}{c}P\left[\begin{array}{c}{i}_{\mathrm{\&alpha;u}}\\ i_{\mathrm{\&beta;u}}\end{array}\right]={\left[\begin{array}{cc}{L}_0+L_1\cos 2{\mathrm{\&theta;}}_r& L_1\sin 2{\mathrm{\&theta;}}_r\\ L_1\sin 2{\mathrm{\&theta;}}_r& L_0-L_1\cos 2{\mathrm{\&theta;}}_r\end{array}\right]}^{-1}\left[\begin{array}{c}{u}_{\mathrm{\&alpha;u}}\\ u_{\mathrm{\&beta;u}}\end{array}\right]\\ =\frac{1}{L_d{L}_q}\left[\begin{array}{cc}{L}_0-L_1\cos 2{\mathrm{\&theta;}}_r& -L_1\sin 2{\mathrm{\&theta;}}_r\\ -L_1\sin 2{\mathrm{\&theta;}}_r& L_0+L_1\cos 2{\mathrm{\&theta;}}_r\end{array}\right]\left[\begin{array}{c}{u}_{\mathrm{\&alpha;u}}\\ u_{\mathrm{\&beta;u}}\end{array}\right]\end{array}$

Therefore, can obtain:

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;u}}\left(t\right)\\ i_{\mathrm{\&beta;u}}\left(t\right)\end{array}\right]=\frac{t}{L_d{L}_q}\left[\begin{array}{cc}{L}_0-L_1\cos 2{\mathrm{\&theta;}}_r& -L_1\sin 2{\mathrm{\&theta;}}_r\\ -L_1\sin 2{\mathrm{\&theta;}}_r& L_0+L_1\cos 2{\mathrm{\&theta;}}_r\end{array}\right]\left[\begin{array}{c}{u}_{\mathrm{\&alpha;u}}\\ u_{\mathrm{\&beta;u}}\end{array}\right]$

Again due to $\left[\begin{array}{c}{u}_{\mathrm{\&alpha;u}}\\ u_{\mathrm{\&beta;u}}\end{array}\right]=\frac{2}{3}\left[\begin{array}{c}{u}_{\mathrm{dc}}\\ 0\end{array}\right],$ Therefore,

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;u}}\left(t\right)\\ i_{\mathrm{\&beta;u}}\left(t\right)\end{array}\right]=\frac{2}{3}\frac{t}{L_d{L}_q}\left[\begin{array}{cc}{L}_0-L_1\cos 2{\mathrm{\&theta;}}_r& -L_1\sin 2{\mathrm{\&theta;}}_r\\ -L_1\sin 2{\mathrm{\&theta;}}_r& L_0+L_1\cos 2{\mathrm{\&theta;}}_r\end{array}\right]\left[\begin{array}{c}{u}_{\mathrm{dc}}\\ 0\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2{\mathrm{\&theta;}}_r\\ I_2\sin 2{\mathrm{\&theta;}}_r\end{array}\right]$

Wherein, $I_1=\frac{1}{3}\frac{L_q+L_d}{L_d{L}_q}{u}_{\mathrm{dc}}t,I_2=\frac{1}{3}\frac{L_q-L_d}{L_d{L}_q}{u}_{\mathrm{dc}}t,$ This shows, I ₁, I ₂with the rotor-position of permagnetic synchronous motor and rotating speed all irrelevant, only with the quadrature axis inductance parameters L of permagnetic synchronous motor _q, d-axis inductance parameters L _d, apply the first voltage vector the first preset time t ₁value t and DC bus-bar voltage u _dcrelevant; Pass through $I_1=\frac{1}{3}\frac{L_q+L_d}{L_d{L}_q}{u}_{\mathrm{dc}}t,I_2=\frac{1}{3}\frac{L_q-L_d}{L_d{L}_q}{u}_{\mathrm{dc}}t$ Quadrature axis inductance parameters L can be drawn _q, and d-axis inductance parameters L _d.

Preferably, permagnetic synchronous motor is sampled respectively at the first voltage vector second voltage vector with tertiary voltage vector electric current under effect, and calculate the first current variable I ₁with the second current variable I ₂, comprise the steps:

S420, sampling permagnetic synchronous motor is respectively at the second voltage vector with tertiary voltage vector under effect, the first current i of generation _v(t) and the second current i _w(t);

S430, to the first current i _v(t) and the second current i _wt () carries out Clarke conversion respectively, obtain the first current i _vt () is at α _vβ _vexpression i under coordinate system _v(t)=[i _{α v}(t), i _{β v}(t)] ^t, and the second current i _wt () is at α _wβ _wexpression i under coordinate system _w(t)=[i _{α w}(t), i _{β w}(t)] ^t;

S440, respectively to the first current i _vt () is at α _vβ _vexpression i under coordinate system _v(t)=[i _{α v}(t), i _{β v}(t)] ^t, and the second current i _wt () is at α _wβ _wexpression i under coordinate system _w(t)=[i _{α w}(t), i _{β w}(t)] ^tcarry out current transformation, obtain

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;v}}\left(t\right)\\ i_{\mathrm{\&beta;v}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2({\mathrm{\&theta;}}_r-\frac{2}{3}\mathrm{\&pi;})\\ I_2\sin 2({\mathrm{\&theta;}}_r-\frac{2}{3}\mathrm{\&pi;})\end{array}\right];$

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;w}}\left(t\right)\\ i_{\mathrm{\&beta;w}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2({\mathrm{\&theta;}}_r+\frac{2}{3}\mathrm{\&pi;})\\ I_2\sin 2({\mathrm{\&theta;}}_r+\frac{2}{3}\mathrm{\&pi;})\end{array}\right].$

When applying second voltage vector time, definition permagnetic synchronous motor V phase direction is α _vaxle, 90 ° of directions, advanced V phase direction are β _vaxle, permagnetic synchronous motor is at the second voltage vector lower generation first electric current of effect is i _vt (), by i _vt () is sampled, and carry out Clarke conversion, obtains i _v(t)=[i _{α v}(t), i _{β v}(t)] ^t;

When applying tertiary voltage vector time, definition permagnetic synchronous motor W phase direction is α _waxle, 90 ° of directions, advanced V phase direction are β _waxle, permagnetic synchronous motor is at tertiary voltage vector lower generation second electric current of effect is i _wt (), by i _wt () is sampled, and carry out Clarke conversion, obtains i _w(t)=[i _{α w}(t), i _{β w}(t)] ^t;

By to i _v(t)=[i _{α v}(t), i _{β v}(t)] ^tand i _w(t)=[i _{α w}(t), i _{β w}(t)] ^tcarry out current transformation, obtain:

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;v}}\left(t\right)\\ i_{\mathrm{\&beta;v}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2({\mathrm{\&theta;}}_r-\frac{2}{3}\mathrm{\&pi;})\\ I_2\sin 2({\mathrm{\&theta;}}_r-\frac{2}{3}\mathrm{\&pi;})\end{array}\right];$

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;w}}\left(t\right)\\ i_{\mathrm{\&beta;w}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2({\mathrm{\&theta;}}_r+\frac{2}{3}\mathrm{\&pi;})\\ I_2\sin 2({\mathrm{\&theta;}}_r+\frac{2}{3}\mathrm{\&pi;})\end{array}\right].$

By above-mentioned two formulas and $\left[\begin{array}{c}{i}_{\mathrm{\&alpha;u}}\left(t\right)\\ i_{\mathrm{\&beta;u}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2{\mathrm{\&theta;}}_r\\ I_2\sin 2{\mathrm{\&theta;}}_r\end{array}\right],$ Calculate:

$I_1=\frac{(i_{\mathrm{\&alpha;u}}\left(t\right)+i_{\mathrm{\&alpha;v}}\left(t\right)+i_{\mathrm{\&alpha;w}}\left(t\right))}{3};$

$I_2=\sqrt{\frac{2}{3}(i_{\mathrm{\&beta;u}}^2\left(t\right)+i_{\mathrm{\&beta;v}}^2\left(t\right)+i_{\mathrm{\&beta;w}}^2\left(t\right))};$

$I_2=\sqrt{\frac{2}{3}({(i_{\mathrm{\&alpha;u}}\left(t\right)-I_1)}^2+{(i_{\mathrm{\&alpha;v}}\left(t\right)-I_1)}^2+{(i_{\mathrm{\&alpha;w}}\left(t\right)-I_1)}^2)};$

The first current variable I1 and the second current variable I is obtained according to above-mentioned formula ₂, the winding loading duration simultaneously to permagnetic synchronous motor is the first preset time t ₁the first voltage vector time the DC bus-bar voltage u that detects _dcfor $\left[\begin{array}{c}{u}_{\mathrm{\&alpha;u}}\\ u_{\mathrm{\&beta;u}}\end{array}\right]=\frac{2}{3}\left[\begin{array}{c}{u}_{\mathrm{dc}}\\ 0\end{array}\right],$ Therefore, as a kind of embodiment, according to DC bus-bar voltage u _dc, the first current variable I ₁with the second current variable I ₂, calculate the quadrature axis inductance parameters L of permagnetic synchronous motor _q, and the d-axis inductance parameters L of permagnetic synchronous motor _d, comprise the steps:

According to formula:

$\left\{\begin{array}{c}{L}_d=\frac{2}{3}\frac{u_{\mathrm{dc}}t}{I_1+I_2}\\ L_q=\frac{2}{3}\frac{u_{\mathrm{dc}}t}{I_1-I_2}\end{array}\right.$

The quadrature axis inductance parameters L of permagnetic synchronous motor can be calculated _q, and the d-axis inductance parameters L of permagnetic synchronous motor _d.

Accordingly, based on same inventive concept, present invention also offers permagnetic synchronous motor cross, straight axle inductance parameters off-line identification system, because permagnetic synchronous motor cross, straight axle inductance parameters off-line identification system principle is substantially identical with permagnetic synchronous motor cross, straight axle inductance parameters offline identification method principle, therefore, repeat part to repeat no more.

See Fig. 2 and Fig. 3, a kind of permagnetic synchronous motor cross, straight axle inductance parameters off-line identification system 200, comprise pulse signal generator 210, inverter 220, control unit 230, Clarke converter unit 240, current transformation unit 250 and inductance computing unit 260, wherein:

The output of pulse signal generator 210 is connected with the input of inverter 220, and the output of inverter 220 is connected with the input of permagnetic synchronous motor 270;

Control unit 230 comprises the first control subelement 231, second and controls subelement 232, the 3rd control subelement 233 and the first detection sub-unit 234, wherein:

First controls subelement 231, be zero for controlling permagnetic synchronous motor 270 winding current that is static and permagnetic synchronous motor 270, the lower brachium pontis of brachium pontis, V phase and W phase in U phase in conduction inverter 220, disconnects U phase in inverter 220 lower brachium pontis, V phase and brachium pontis in W phase, at α _uβ _uunder coordinate system, control wave generator 210 is the first preset time t to the winding loading duration of permagnetic synchronous motor 270 ₁the first voltage vector

Second controls subelement 232, for the lower brachium pontis of brachium pontis, U phase and W phase in V phase in conduction inverter 220, disconnects V phase in inverter 220 lower brachium pontis, U phase and brachium pontis in W phase, at α _vβ _vunder coordinate system, control wave generator 210 is the second preset time t to the winding loading duration of permagnetic synchronous motor 270 ₂the second voltage vector

3rd controls subelement 233, for the lower brachium pontis of brachium pontis, U phase and V phase in W phase in conduction inverter 220, disconnects W phase in inverter 220 lower brachium pontis, U phase and brachium pontis in V phase, at α _wβ _wunder coordinate system, control wave generator 210 is the 3rd preset time t to the winding loading duration of permagnetic synchronous motor 270 ₃tertiary voltage vector

First detection sub-unit 234, for detecting DC bus-bar voltage u _dc;

Clarke converter unit 240, for sampling permagnetic synchronous motor 270 respectively at the first voltage vector second voltage vector with tertiary voltage vector electric current under effect, and carry out Clarke conversion;

Current transformation unit 250, carries out the permagnetic synchronous motor 270 after Clarke conversion at the first voltage vector for basis second voltage vector with tertiary voltage vector electric current under effect, calculates the first current variable I ₁with the second current variable I ₂;

Inductance computing unit 260, for according to DC bus-bar voltage u _dc, the first current variable I ₁with the second current variable I ₂, calculate the quadrature axis inductance parameters L of permagnetic synchronous motor 270 _q, and the d-axis inductance parameters L of permagnetic synchronous motor 270 _d;

Wherein, the first preset time t ₁, the second preset time t ₂with the 3rd preset time t ₃all be less than d axle time constant and be less than q axle time constant r _sfor the phase resistance parameter of permagnetic synchronous motor.

What deserves to be explained is, the second voltage vector advanced first voltage vector in direction 120 °, direction, tertiary voltage vector advanced second voltage vector in direction 120 °, direction;

α _uaxle is permagnetic synchronous motor U phase direction, β _uaxle is the advanced U phase of permagnetic synchronous motor 90 ° of directions; α _vaxle is permagnetic synchronous motor V phase direction, β _vaxle is the advanced V phase of permagnetic synchronous motor 90 ° of directions; α _waxle is permagnetic synchronous motor W phase direction, β _waxle is the advanced W phase of permagnetic synchronous motor 90 ° of directions.

Preferably, the first preset time t ₁, the second preset time t ₂with the 3rd preset time t ₃equal, and value is t.

Preferably, Clarke converter unit 240 comprises the first sampling subelement and the first varitron unit, and current transformation unit comprises the second varitron unit and the 3rd varitron unit, wherein:

First sampling subelement, for sampling permagnetic synchronous motor respectively at the second voltage vector with tertiary voltage vector under effect, the first current i of generation _v(t) and the second current i _w(t);

First varitron unit, for the first current i _v(t) and the second current i _wt () carries out Clarke conversion respectively, obtain the first current i _vt () is at α _vβ _vexpression i under coordinate system _v(t)=[i _{α v}(t), i _{β v}(t)] ^t, and the second current i _wt () is at described α _wβ _wexpression i under coordinate system _w(t)=[i _{α w}(t), i _{β w}(t)] ^t;

Second varitron unit, for the first current i _vt () is at α _vβ _vexpression i under coordinate system _v(t)=[i _{α v}(t), i _{β v}(t)] ^tcarry out current transformation, obtain:

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;v}}\left(t\right)\\ i_{\mathrm{\&beta;v}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2({\mathrm{\&theta;}}_r-\frac{2}{3}\mathrm{\&pi;})\\ I_2\sin 2({\mathrm{\&theta;}}_r-\frac{2}{3}\mathrm{\&pi;})\end{array}\right];$

3rd varitron unit, for the second current i _wt () is at α _wβ _wexpression i under coordinate system _w(t)=[i _{α w}(t), i _{β w}(t)] ^tcarry out current transformation, obtain:

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;w}}\left(t\right)\\ i_{\mathrm{\&beta;w}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2({\mathrm{\&theta;}}_r+\frac{2}{3}\mathrm{\&pi;})\\ I_2\sin 2({\mathrm{\&theta;}}_r+\frac{2}{3}\mathrm{\&pi;})\end{array}\right].$

As a kind of embodiment, inductance computing unit 260, for according to formula:

$\left\{\begin{array}{c}{L}_d=\frac{2}{3}\frac{u_{\mathrm{dc}}t}{I_1+I_2}\\ L_q=\frac{2}{3}\frac{u_{\mathrm{dc}}t}{I_1-I_2}\end{array}\right.$

Calculate the quadrature axis inductance parameters L of permagnetic synchronous motor _q, and the d-axis inductance parameters L of permagnetic synchronous motor _d.

The above embodiment only have expressed several execution mode of the present invention, and it describes comparatively concrete and detailed, but therefore can not be interpreted as the restriction to the scope of the claims of the present invention.It should be pointed out that for the person of ordinary skill of the art, without departing from the inventive concept of the premise, can also make some distortion and improvement, these all belong to protection scope of the present invention.Therefore, the protection range of patent of the present invention should be as the criterion with claims.

Claims (10)

1. a permagnetic synchronous motor cross, straight axle inductance parameters offline identification method, is characterized in that, comprise the steps:

Controlling permagnetic synchronous motor winding current that is static and described permagnetic synchronous motor is zero, and in conduction inverter, the lower brachium pontis of brachium pontis, V phase and W phase in U phase, disconnects U phase in described inverter lower brachium pontis, V phase and brachium pontis in W phase, at α _uβ _uunder coordinate system, it is the first preset time t that the winding to described permagnetic synchronous motor loads duration ₁the first voltage vector

The lower brachium pontis of brachium pontis, U phase and W phase in V phase in inverter described in conducting, disconnects V phase in described inverter lower brachium pontis, U phase and brachium pontis in W phase, at α _vβ _vunder coordinate system, it is the second preset time t that the winding to described permagnetic synchronous motor loads duration ₂the second voltage vector

The lower brachium pontis of brachium pontis, U phase and V phase in W phase in inverter described in conducting, disconnects W phase in described inverter lower brachium pontis, U phase and brachium pontis in V phase, at α _wβ _wunder coordinate system, it is the 3rd preset time t that the winding to described permagnetic synchronous motor loads duration ₃tertiary voltage vector

Detect DC bus-bar voltage u _dc, and sample described permagnetic synchronous motor respectively at described first voltage vector described second voltage vector with described tertiary voltage vector electric current under effect, and calculate the first current variable I ₁with the second current variable I2;

According to described DC bus-bar voltage u _dc, described first current variable I ₁with described second current variable I ₂, calculate the quadrature axis inductance parameters L of described permagnetic synchronous motor _q, and the d-axis inductance parameters L of described permagnetic synchronous motor _d;

Wherein, described first preset time t ₁, described second preset time t ₂with described 3rd preset time t ₃all be less than d axle time constant and be less than q axle time constant r _sfor the phase resistance parameter of described permagnetic synchronous motor.

2. permagnetic synchronous motor according to claim 1 cross, straight axle inductance parameters offline identification method, is characterized in that, described second voltage vector direction is described first voltage vector in advance 120 °, direction, described tertiary voltage vector direction is described second voltage vector in advance 120 °, direction;

α _uaxle is described permagnetic synchronous motor U phase direction, β _uaxle is the advanced U phase of described permagnetic synchronous motor 90 ° of directions; α _vaxle is described permagnetic synchronous motor V phase direction, β _vaxle is the advanced V phase of described permagnetic synchronous motor 90 ° of directions; α _waxle is described permagnetic synchronous motor W phase direction, β _wthe advanced W phase of permagnetic synchronous motor described in axle 90 ° of directions.

3. permagnetic synchronous motor according to claim 2 cross, straight axle inductance parameters offline identification method, is characterized in that, described first preset time t ₁, described second preset time t ₂with described 3rd preset time t ₃equal, and value is t.

4. permagnetic synchronous motor according to claim 3 cross, straight axle inductance parameters offline identification method, is characterized in that, the described permagnetic synchronous motor of described sampling is respectively at described first voltage vector described second voltage vector with described tertiary voltage vector electric current under effect, and calculate the first current variable I ₁with the second current variable I ₂, comprise the steps:

Sample described permagnetic synchronous motor respectively at described second voltage vector with described tertiary voltage vector under effect, the first current i of generation _v(t) and the second current i _w(t);

To described first current i _v(t) and described second current i _wt () carries out Clarke conversion respectively, obtain described first current i _vt () is at described α _vβ _vexpression iv under coordinate system ₍t)=[i _{α v}(t), i _{β v}(t)] ^t, and described second current i _wt () is at described α _wβ _wexpression i under coordinate system _w(t)=[i _{α w}(t), i _{β w}(t)] ^t;

Respectively to described first current i _vt () is at described α _vβ _vexpression i under coordinate system _v(t)=[i _{α v}(t), i _{β v}(t)] ^t, and described second current i _wt () is at described α _wβ _wexpression i under coordinate system _w(t)=[i _{α w}(t), i _{β w}(t)] ^tcarry out current transformation, obtain

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;v}}\left(t\right)\\ i_{\mathrm{\&beta;v}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2({\mathrm{\&theta;}}_r-\frac{2}{3}\mathrm{\&pi;})\\ I_2\sin 2({\mathrm{\&theta;}}_r-\frac{2}{3}\mathrm{\&pi;})\end{array}\right];$

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;w}}\left(t\right)\\ i_{\mathrm{\&beta;w}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2({\mathrm{\&theta;}}_r+\frac{2}{3}\mathrm{\&pi;})\\ I_2\sin 2({\mathrm{\&theta;}}_r+\frac{2}{3}\mathrm{\&pi;})\end{array}\right].$

5. permagnetic synchronous motor according to claim 4 cross, straight axle inductance parameters offline identification method, is characterized in that, described according to described DC bus-bar voltage u _dc, described first current variable I ₁with described second current variable I ₂, calculate the quadrature axis inductance parameters L of described permagnetic synchronous motor _q, and the d-axis inductance parameters L of described permagnetic synchronous motor _d, comprise the steps:

According to formula:

$\left\{\begin{array}{c}{L}_d=\frac{2}{3}\frac{u_{\mathrm{dc}}t}{I_1+I_2}\\ L_q=\frac{2}{3}\frac{u_{\mathrm{dc}}t}{I_1-I_2}\end{array}\right.$

Calculate the quadrature axis inductance parameters L of described permagnetic synchronous motor _q, and the d-axis inductance parameters L of described permagnetic synchronous motor _d.

6. a permagnetic synchronous motor cross, straight axle inductance parameters off-line identification system, is characterized in that, comprises pulse signal generator, inverter, Clarke converter unit, current transformation unit, control unit and inductance computing unit, wherein:

The output of described pulse signal generator is connected with the input of described inverter, and the output of described inverter is connected with the input of permagnetic synchronous motor;

Described control unit comprises the first control subelement, second and controls subelement, the 3rd control subelement and the first detection sub-unit, wherein:

Described first controls subelement, be zero for controlling described permagnetic synchronous motor winding current that is static and described permagnetic synchronous motor, the lower brachium pontis of brachium pontis, V phase and W phase in U phase in conduction inverter, disconnects U phase in described inverter lower brachium pontis, V phase and brachium pontis in W phase, at α _uβ _uunder coordinate system, control winding from described pulse signal generator to described permagnetic synchronous motor load duration be the first preset time t ₁the first voltage vector

Described second controls subelement, for the lower brachium pontis of brachium pontis, U phase and W phase in V phase in inverter described in conducting, disconnects V phase in described inverter lower brachium pontis, U phase and brachium pontis in W phase, at α _vβ _vunder coordinate system, control winding from described pulse signal generator to described permagnetic synchronous motor load duration be the second preset time t ₂the second voltage vector

Described 3rd controls subelement, for the lower brachium pontis of brachium pontis, U phase and V phase in W phase in inverter described in conducting, disconnects W phase in described inverter lower brachium pontis, U phase and brachium pontis in V phase, at α _wβ _wunder coordinate system, control winding from described pulse signal generator to described permagnetic synchronous motor load duration be the 3rd preset time t ₃tertiary voltage vector

Described first detection sub-unit, for detecting DC bus-bar voltage u _dc;

Described Clarke converter unit, for sampling described permagnetic synchronous motor respectively at described first voltage vector described second voltage vector with described tertiary voltage vector electric current under effect, and carry out Clarke conversion;

Described current transformation unit, carries out the described permagnetic synchronous motor after described Clarke conversion at described first voltage vector for basis described second voltage vector with described tertiary voltage vector electric current under effect, calculates the first current variable I ₁with the second current variable I ₂;

Described inductance computing unit, for according to described DC bus-bar voltage u _dc, described first current variable I ₁with described second current variable I ₂, calculate the quadrature axis inductance parameters L of described permagnetic synchronous motor _q, and the d-axis inductance parameters L of described permagnetic synchronous motor _d;

Wherein, described first preset time t ₁, described second preset time t ₂with described 3rd preset time t ₃all be less than d axle time constant and be less than q axle time constant r _sfor the phase resistance parameter of described permagnetic synchronous motor.

7. permagnetic synchronous motor according to claim 6 cross, straight axle inductance parameters off-line identification system, is characterized in that, described second voltage vector direction is described first voltage vector in advance 120 °, direction, described tertiary voltage vector direction is described second voltage vector in advance 120 °, direction;

α _uaxle is described permagnetic synchronous motor U phase direction, β _uaxle is the advanced U phase of described permagnetic synchronous motor 90 ° of directions; α _vaxle is described permagnetic synchronous motor V phase direction, β _vaxle is the advanced V phase of described permagnetic synchronous motor 90 ° of directions; α _waxle is described permagnetic synchronous motor W phase direction, β _waxle is the advanced W phase of described permagnetic synchronous motor 90 ° of directions.

8. permagnetic synchronous motor according to claim 7 cross, straight axle inductance parameters off-line identification system, is characterized in that, described first preset time t ₁, described second preset time t ₂with described 3rd preset time t ₃equal, and value is t.

9. permagnetic synchronous motor according to claim 8 cross, straight axle inductance parameters off-line identification system, it is characterized in that, described Clarke converter unit comprises the first sampling subelement and the first varitron unit, described current transformation unit comprises the second varitron unit and the 3rd varitron unit, wherein:

Described first sampling subelement, for sampling described permagnetic synchronous motor respectively at described second voltage vector with described tertiary voltage vector under effect, the first current i of generation _v(t) and the second current i _w(t);

Described first varitron unit, for described first current i _v(t) and described second current i _wt () carries out Clarke conversion respectively, obtain described first current i _vt () is at described α _vβ _vexpression i under coordinate system _v(t)=[i _{α v}(t), i _{β v}(t)] ^t, and described second current i _wt () is at described α _wβ _wexpression i under coordinate system _w(t)=[i _{α w}(t), i _{β w}(t)] ^t;

Described second varitron unit, for described first current i _vt () is at described α _vβ _vexpression i under coordinate system _v(t)=[i _{α v}(t), i _{β v}(t)] ^tcarry out current transformation, obtain:

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;v}}\left(t\right)\\ i_{\mathrm{\&beta;v}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2({\mathrm{\&theta;}}_r-\frac{2}{3}\mathrm{\&pi;})\\ I_2\sin 2({\mathrm{\&theta;}}_r-\frac{2}{3}\mathrm{\&pi;})\end{array}\right];$

Described 3rd varitron unit, for described second current i _wt () is at described α _wβ _wexpression i under coordinate system _w(t)=[i _{α w}(t), i _{β w}(t)] ^tcarry out current transformation, obtain:

$\left[\begin{array}{c}{i}_{\mathrm{\&alpha;w}}\left(t\right)\\ i_{\mathrm{\&beta;w}}\left(t\right)\end{array}\right]=\left[\begin{array}{c}{I}_1+I_2\cos 2({\mathrm{\&theta;}}_r+\frac{2}{3}\mathrm{\&pi;})\\ I_2\sin 2({\mathrm{\&theta;}}_r+\frac{2}{3}\mathrm{\&pi;})\end{array}\right].$

10. permagnetic synchronous motor according to claim 9 cross, straight axle inductance parameters off-line identification system, is characterized in that, described inductance computing unit, for according to formula:

$\left\{\begin{array}{c}{L}_d=\frac{2}{3}\frac{u_{\mathrm{dc}}t}{I_1+I_2}\\ L_q=\frac{2}{3}\frac{u_{\mathrm{dc}}t}{I_1-I_2}\end{array}\right.$

Calculate the quadrature axis inductance parameters L of described permagnetic synchronous motor _q, and the d-axis inductance parameters L of described permagnetic synchronous motor _d.