CN103715962B - The permagnetic synchronous motor sliding-mode speed observer that dual stage matrix converter drives - Google Patents

Abstract

The permasyn morot sliding-mode speed observer that dual stage matrix converter drives, including motor model based on sliding mode observer, S type switch function, angle calculation module and angle rotating speed computing module；Stator voltage u under the biphase rest frame of permagnetic synchronous motor_αAnd u_βObtained and S type switch function output by voltage reconstructionWithInput as motor model based on sliding mode observer, motor model output stator current observation based on sliding mode observerSubtract stator actual current value i_α、i_β, differenceAs the input of S type switch function, after being processed, export the back-emf estimated value under biphase rest frameWithRotor-position is obtained again through angle calculation moduleAngular velocity is obtained through angular speed calculation module derivation

Description

The permagnetic synchronous motor sliding-mode speed observer that dual stage matrix converter drives

Technical field

The invention belongs to magneto control field, the permagnetic synchronous motor relating to the driving of a kind of dual stage matrix converter is sliding Mould speed observer.

Background technology

Along with expanding economy, power electronic equipment is widely used in the industry, but is creating huge warp Also huge harmonic wave is brought to electrical network while Ji benefit.Therefore, exploitation environmental protection, compact conformation efficient Novel electric again Power electronic installation has just become a kind of development trend.Dual stage matrix converter (Two-stage Matrix Converter, TSMC) It is a kind of new A C/AC " green " power converter that gets up of developed recently, has that Harmonics of Input content is few, power density High, input power factor is controlled, energy capable of bidirectional flowing, DC side be without advantages such as storage capacitors.

Permagnetic synchronous motor (Permanent Magnet Synchronous Motor, PMSM) is without idle excitation electricity Stream, efficiency is high, and volume is little, is widely used because of advantages such as its high power density, high torque (HT) current ratio again.

In high-performance permanent magnet synchronous motor system, in order to realize high accuracy, the speed of high dynamic performance and position control, Speed is essential with the closed loop of position, it is therefore desirable to install mechanical sensor on armature spindle, to measure rotor speed Degree and position.Mechanical sensor often makes system bulk and weight increase, and therefore cost increase limits permanent magnet synchronous electric Machine is in the application of some special occasions.In order to overcome this defect, permagnetic synchronous motor senseless control technology becomes One study hotspot of Motor Control Field.

For the advantage that TSMC and PMSM and deadlock_free scheduling are each unique, by triplicity, can play each From unique advantage, then TSMC-PMSM Speed Sensorless System becomes a new research direction of Motor Control Field.

Permagnetic synchronous motor senseless control technology estimated speed and the whether accurate of position are successful keys. The method of permagnetic synchronous motor velocity estimation mainly has direct estimation method based on mathematical model, model reference adaptive method at present And evaluation method based on observer etc..Model reference adaptive estimation algorithm is relevant with choosing of reference model itself, and Model reference adaptive estimation algorithm and direct estimation method all rely on the parameter of electric machine, thus have impact on the accuracy of estimation.Utilize The method that rotor-position and angle are estimated by state observer mainly has three kinds: sliding mode observer, Luenberger observe Device and full-order adaptive state observer.

Sliding mode observer is according to predetermined sliding mode orbiting motion according to current state control system, is sliding Cheng Zhong, sliding mode is unrelated with the parameter of object and disturbance, has physics realization simple, and on-line identification, fast response time, to disturbing Dynamic insensitive, the advantage such as strong robustness and be widely used, be above-mentioned three kinds of observers to use at most, the most ripe observation Device, therefore TSMC-PMSM system based on Sliding-mode observer is the position Sensorless Control system of the most most future System.

Existing tradition sliding mode observer theory diagram such as Fig. 2, need using the switching signal of voltage, electric current and estimation as PMSM mode input amount, using sign function sign as switching function, it is thus achieved that switching signal, then is estimated by low pass filter acquisition The back-emf calculated, then relies on trigonometric function to calculate and obtains rotating speed and positional information, and the method is to the parameter of control object and disturbs Dynamic have the strongest robustness.But due to switch time and spatially delayed so that sliding mode observer presents intrinsic shake Phenomenon, estimation electric current is shaken up and down along actual current amplitude, causes the back-emf of estimation to there is also pulsation；Add low-pass filtering The time delay that the use of device causes, need to cause low pass filter delayed compensates, and backoff algorithm to realize quickly responding, It is required for friction speed point and builds table, thus cause tradition sliding mode observer to there is shake, time delay, build table workload greatly, waste The problems such as memory space and algorithm are complicated.

Summary of the invention

It is an object of the invention to provide the permagnetic synchronous motor sliding formwork speed observation that a kind of dual stage matrix converter drives Device, solves sliding mode observer shake, time delay that prior art exists, to build table workload big and waste the problems such as memory space.

The technical solution adopted in the present invention, the permagnetic synchronous motor sliding formwork speed observation that dual stage matrix converter drives Device, including motor model based on sliding mode observer, S type switch function, angle calculation module and angular speed calculation module；Pass through Stator voltage u under the biphase rest frame of permagnetic synchronous motor that voltage reconstruction obtains_αAnd u_βOutput with S type switch function AmountWithAs the input of motor model based on sliding mode observer, motor model output stator based on sliding mode observer electricity Stream observationSubtract stator actual current value i_α、i_β, stator current errorAs the input of S type switch function, The back-emf estimated value under biphase rest frame is exported after being processedWithBack-emf under biphase rest frame is estimated Calculation valueWithFor the output of S type switch function (2), then obtain rotor-position through angle calculation moduleThrough turn meter Calculate module derivation and obtain angular velocity

The feature of the present invention also resides in:

S type switch function expression formula is as follows:

$\left\{\begin{array}{c}H\left({\stackrel{\‾}{i}}_{\mathrm{\α}}\right)=\frac{2}{1+\exp (-a{\stackrel{\‾}{i}}_{\mathrm{\α}})}-1\\ H\left({\stackrel{\‾}{i}}_{\mathrm{\β}}\right)=\frac{2}{1+\exp (-a{\stackrel{\‾}{i}}_{\mathrm{\β}})}-1\end{array}\right.---\left(8\right)$

In formula, a is the constant of the regulation S type switch function gradient, takes positive number；Stator current error

Motor model expression formula is as follows:

$\left\{\begin{array}{c}\frac{d{\stackrel{\‾}{i}}_{\mathrm{\α}}}{dt}=-\frac{R}{L}{\stackrel{\‾}{i}}_{\mathrm{\α}}+\frac{1}{L}{e}_{\mathrm{\α}}-\frac{1}{L}kH\left({\stackrel{\‾}{i}}_{\mathrm{\α}}\right)\\ \frac{d{\stackrel{\‾}{i}}_{\mathrm{\β}}}{dt}=-\frac{R}{L}{\stackrel{\‾}{i}}_{\mathrm{\β}}+\frac{1}{L}{e}_{\mathrm{\β}}-\frac{1}{L}kH\left({\stackrel{\‾}{i}}_{\mathrm{\β}}\right)\end{array}\right.---\left(9\right)$

In formula, k is mould gain coefficient, and R, L are respectively the stator resistance of permagnetic synchronous motor, inductance, e_α、e_βFor static seat Back-emf under mark system.

S type switch function, using stator current error as input, is not reaching to S type switch function at this stator current error The when of upper and lower two diverter surfaces, the switching signal of output be entered as exponential relationship, error reaches output etc. during diverter surface In 1, when reaching lower diverter surface, output is equal to-1；A is the biggest, and S type switch function more levels off to sign function.

There is advantages that

1, the present invention utilizes and coordinates S type switch function formation sliding mode observer novel with the sliding formwork gain coefficient of rotation speed change Switch function thus solve conventional symbols switch function exist shake and latency issue, and obtain save low pass filter and Pang The good result of big angle compensation table, to reach raising system rapidity and to save the purpose of memory space.

2, S type switch function sliding-mode speed observer of the present invention is applied to TSMC-PMSM system, above-mentioned making system have Advantage has more that Harmonics of Input is little, power factor is high simultaneously and DC side is without the advantage of storage capacitor.

3, the present invention utilizes TSMC to drive the scheme of PMSM to reduce Harmonics of Input, improves input power factor and goes Except the purpose of storage capacitor, and one S type switch function is used to replace sign function sign to switch letter as sliding mode observer The problems such as the scheme of number eliminates shake, time delay that tradition sliding mode observer brings, to build table workload big, waste memory space.

4, sliding mode observer of the present invention carries out velocity estimation in TSMC-PMSM Speed Sensorless System, opens by S type Closing function replaces sign function sign as sliding mode observer switch function, solves existing TSMC-PMSM system conventional sliding formwork and sees Survey shake, latency issue that device breaker in middle function brings, and eliminate low pass filter and angle compensation module, eliminate compensation Link builds table workload greatly, the deficiency of waste memory space.

Accompanying drawing explanation

Fig. 1 is that the TSMC-PMSM of sliding-mode speed observer of the present invention is without velocity control system block diagram；

Fig. 2 is traditional sliding mode observer theory diagram based on symbol switch function；

Fig. 3 is sliding-mode speed observer theory diagram of the present invention；

Fig. 4 is S type switch function of the present invention and the design principle of sliding-mode surface x and coefficient selection rule schematic diagram；

Fig. 5 is that (motor is from 480r/min with speed dynamic response curve under tradition sliding mode observer method for the inventive method Prominent speed dynamic response wave shape when accelerating to 960r/min)；

Fig. 6 be motor when 480r/min, the counter electromotive force experiment of tradition sliding mode observer and observer of the present invention estimation Waveform；

Fig. 7 be motor when 960r/min, the counter electromotive force experiment of tradition sliding mode observer and observer of the present invention estimation Waveform；

Fig. 8 be motor when 480r/min, tradition sliding mode observer under actual electrical angle θ, estimation electrical angleAnd electric angle Degree error experiments waveform；

Fig. 9 be motor when 960r/min, tradition sliding mode observer under actual electrical angle θ, estimation electrical angleAnd electric angle Degree error experiments waveform；

Figure 10 be motor when 480r/min, actual electrical angle θ of the inventive method gained, estimation electrical angleAnd electrical angle Error experiments waveform；

Figure 11 be motor when 960r/min, actual electrical angle θ of the inventive method gained, estimation electrical angleAnd electrical angle Error experiments waveform；

In figure, 1. motor model based on sliding mode observer, 2.S type switch function, 3. angle calculation module, 4. angular velocity Computing module.

Detailed description of the invention

With detailed description of the invention, the present invention is elaborated below in conjunction with the accompanying drawings.

The permagnetic synchronous motor sliding-mode speed observer that dual stage matrix converter drives, including electricity based on sliding mode observer Machine model 1, S type switch function 2, angle calculation module 3 and angular speed calculation module 4；The permanent magnetism obtained by voltage reconstruction is same Stator voltage u under the step biphase rest frame of motor_αAnd u_βOutput with S type switch function 2WithAs based on sliding formwork The input of the motor model 1 of observer, motor model 1 output stator current observation based on sliding mode observer Subtract stator actual current value i_α、i_β, stator current errorAs the input of S type switch function 2, after being processed, export two Back-emf estimated value under phase rest frameWithBack-emf estimated value under biphase rest frameWithFor S type The output of switch function (2), then obtain rotor-position through angle calculation module 3Obtain through angular speed calculation module 4 derivation Obtain angular velocity

S type switch function 2 expression formula is as follows:

$\left\{\begin{array}{c}H\left({\stackrel{\‾}{i}}_{\mathrm{\α}}\right)=\frac{2}{1+\exp (-a{\stackrel{\‾}{i}}_{\mathrm{\α}})}-1\\ H\left({\stackrel{\‾}{i}}_{\mathrm{\β}}\right)=\frac{2}{1+\exp (-a{\stackrel{\‾}{i}}_{\mathrm{\β}})}-1\end{array}\right.---\left(8\right)$

In formula, a is the constant of regulation S type switch function 2 gradient, takes positive number；Stator current error

Motor model 1 expression formula based on sliding mode observer is as follows:

$\left\{\begin{array}{c}\frac{d{\stackrel{\‾}{i}}_{\mathrm{\α}}}{dt}=-\frac{R}{L}{\stackrel{\‾}{i}}_{\mathrm{\α}}+\frac{1}{L}{e}_{\mathrm{\α}}-\frac{1}{L}kH\left({\stackrel{\‾}{i}}_{\mathrm{\α}}\right)\\ \frac{d{\stackrel{\‾}{i}}_{\mathrm{\β}}}{dt}=-\frac{R}{L}{\stackrel{\‾}{i}}_{\mathrm{\β}}+\frac{1}{L}{e}_{\mathrm{\β}}-\frac{1}{L}kH\left({\stackrel{\‾}{i}}_{\mathrm{\β}}\right)\end{array}\right.---\left(7\right)$

In formula, k is mould gain coefficient, because: k=k_vaω, e_α=-ψ_fωsinθ,e_β=-ψ_fω cos θ, ensure be System is stable, obtains guaranteeThen take k_va＞ ψ_f；

R, L are respectively the stator resistance of permagnetic synchronous motor, inductance, e_α、e_βFor the back-emf under rest frame.

S type switch function 2, using stator current error as input, is not reaching to S type switch letter at this stator current error The when of number upper and lower two diverter surfaces, the switching signal of output be entered as exponential relationship, output when error reaches diverter surface Equal to 1, when reaching lower diverter surface, output is equal to-1.A is the biggest, and S type switch function 2 more levels off to sign function.

The permagnetic synchronous motor that sliding-mode speed observer of the present invention is applied to dual stage matrix converter driving passes without speed Sensor vector control system carries out velocity estimation.

Sliding mode observer of the present invention is used in TSMC-PMSM Speed Sensorless System carrying out velocity estimation, opens by S type Closing function replaces sign function sign as sliding mode observer switch function, solves existing TSMC-PMSM system conventional sliding formwork and sees Survey shake, latency issue that device breaker in middle function brings, and eliminate low pass filter and angle compensation module, eliminate compensation Link builds table workload greatly, the deficiency of waste memory space.

As it is shown in figure 1, present invention sliding-mode speed observer based on S type switch function is applied in TSMC-PMSM vector control In system processed.TSMC-PMSM vector control system is twin nuclei, is made up of current inner loop and speed outer shroud, uses excitation electricity Stream i_dIt it is the control mode of zero.Line voltage is converted into the input as PMSM of the variable-frequency alternating voltage by TSMC, and PMSM is defeated The electric current gone out is observed as S type sliding formwork as the feedback current of current closed-loop, the output voltage of TSMC and the output electric current of PMSM The input of device, thus obtain motor rotor positionAnd angular velocity informationThe motor rotor position that will obtainBecome as coordinate The angle input quantity changed, it is thus achieved that angular velocityBe converted to rotating speedAs vector controlled velocity feedback quantity, form speed and close Ring.Specifically include:

Step one, variate-value initialize:

The d axle closed loop current of permanent-magnetic synchronous motor stator gives i_drefIn=0, S type switch function: sliding formwork gain coefficient k =k_va·ω_eMiddle k_vaTake the positive number more than rotor flux, here rotor flux ψ_f=0.239 ω b (1.8kw permanent magnet synchronous electric Machine), so taking k_va=0.5；The constant a of the given regulation S type switch function gradient is positive number, and a is the biggest in theory, S type switch letter Several sign function sign that more level off to, take a=10 here.In Fig. 2, in sliding mode observer, the parameter of electric machine is given as (1.8kW permanent magnetism Synchronous motor): resistance R=0.175 Ω, inductance L=8.5mH, the initial input output of sliding mode observer is given is zero: i.e. u_α=0, u_β=0, the electric current of estimationThe back-emf of estimationRotor-position is initial Value is givenEstimated speed initial value gives

Step 2, d axle closed loop current give i_drefSubtract d axle closed loop feedback amount i_dAfter, through the output of electric current pi regulator as closing Loop voltag gives u_dref；After given rotating speed anti-reflection feedback rotating speed (sliding mode observer estimation rotating speed), make through the output of rotating speed pi regulator For q axle closed loop current i_qrefGiven, i_qrefSubtract q axle closed loop feedback amount i_qAfter, export as closed loop voltage through electric current pi regulator u_qrefGiven；Voltage under dq coordinate is given u_dref、u_qrefVoltage Reference amount u being converted under biphase rest frame_αrefWith u_βref, by reference quantity u_αrefAnd u_βrefAs input quantity, utilize space vector width pulse modulation method to generate PWM, and control three contraries Become device output three-phase voltage and drive permagnetic synchronous motor；

The threephase stator electric current i of step 3, permagnetic synchronous motor output_A、i_BAnd i_CIt is converted under biphase rest frame i_α、i_β；Again by i_α、i_βIt is converted into i under biphase rotating coordinate system_d、i_q, i_dAnd i_qAs the current feedback values in step 2；Utilize electricity Ballast structure obtains the input voltage u under the biphase static coordinate of sliding mode observer_α、u_β.Shown in voltage reconstruction mode such as formula (1):

$\left[\begin{array}{c}{u}_A\\ u_B\\ u_C\end{array}\right]=\frac{1}{3}{u}_{dc}\left[\begin{array}{ccc}2& -1& -1\\ -1& 2& -1\\ -1& -1& 2\end{array}\right]\×\left[\begin{array}{c}{t}_a\\ t_b\\ t_c\end{array}\right]---\left(1\right)$

Wherein:,u_imFor input voltage amplitude, cos (θ_i)=max (| cos (θ_a)|,|cos(θ_b)|,| cos(θ_c) |), t_a、t_b、t_cFor the SVPWM on-off action time.Output voltage u will be obtained_A、u_BAnd u_CIt is converted into biphase static coordinate Output voltage u under Xi_α、u_β；

Electric current i under step 4, the biphase rest frame that will obtain in step 3_α、i_βWith output voltage u_α、u_βAs The voltage of sliding mode observer, electric current input quantity；Utilizing zero-order holder by discrete for formula (7), discrete detailed process is as follows:

IfThen:

It is transformed into complex frequency domain,Then its transmission function is:

$G\left(s\right)=\frac{{\hat{i}}_{ss}\left(s\right)}{u_{ss}\left(s\right)-Z\left(s\right)}=\frac{1}{\frac{L}{R}s+1}\·\frac{1}{R}---\left(2\right)$

Utilizing zero-order holder, (2) formula is rewritable is:

$G\left(z\right)=Z\[\frac{1-e^{-Ts}}{s}\·\frac{1}{\frac{L}{R}s+1}\·\frac{1}{R}\]---\left(3\right)$

Because of z=e^Ts, then (3) formula can be written as:

$G\left(z\right)=\frac{(1-e^{-T/\frac{L}{R}})z^{-1}}{R(1-e^{-T/\frac{L}{R}}{z}^{-1})}---\left(4\right)$

And then have

Formula (5) be i.e. discrete after electric current estimation equation, just can obtain current estimation value according to (5) formula

Step 5, the current estimation value utilized in step 4Subtract electric current i in step 3 respectively_α、i_β, it is thus achieved that determine Electron current error is as the input of S type switch function, when this error is not reaching to upper and lower two diverter surfaces of S type switch function Wait, the switching signal of output be entered as exponential relationship, when error reaches diverter surface, output is equal to 1, when reaching lower diverter surface Output is equal to-1.Concrete change trend curve is as shown in Figure 4.

Step 6, utilize the back-emf that step 5 obtainsWithAs input, obtain motor according to formula (11), (12) Rotor-positionAnd angular velocityThen the motor rotor position that will obtainDefeated as step 2, changes in coordinates angle in three Enter amount；The angular velocity that will obtainBe converted to rotating speedAs the velocity feedback quantity in step one, form the PWM arrow that TSMC drives Amount control system.

In order to further illustrate the implementation process of the present invention, theoretical basis is given below:

Permagnetic synchronous motor mathematical model under biphase rest frame alpha-beta is

$\left\{\begin{array}{c}\frac{{\mathrm{di}}_{\mathrm{\α}}}{dt}=-\frac{R}{L}{i}_{\mathrm{\α}}+\frac{1}{L}{u}_{\mathrm{\α}}-\frac{1}{L}{e}_{\mathrm{\α}}\\ \frac{{\mathrm{di}}_{\mathrm{\β}}}{dt}=-\frac{R}{L}{i}_{\mathrm{\β}}+\frac{1}{L}{u}_{\mathrm{\β}}-\frac{1}{L}{e}_{\mathrm{\β}}\\ e_{\mathrm{\α}}=-{\mathrm{\ψ}}_f\mathrm{\ω}\sin \mathrm{\θ}\\ e_{\mathrm{\β}}=-{\mathrm{\ψ}}_f\mathrm{\ω}\cos \mathrm{\θ}\end{array}\right.---\left(6\right)$

I in formula_α、i_β、u_α、u_β、e_α、e_βFor the electric current under rest frame, voltage and back-emf；θ is rotor position angle；R、 L is stator resistance, inductance；ω is rotating speed；ψ_fMagnetic potential for rotor permanent magnet.

According to (6) formula, utilize equivalent control approach method, set up PMSM novel sliding formwork observer model:

$\left\{\begin{array}{c}\frac{d{\hat{i}}_{\mathrm{\α}}}{dt}=-\frac{R}{L}{\hat{i}}_{\mathrm{\α}}+\frac{1}{L}{u}_{\mathrm{\α}}-\frac{1}{L}kH({\hat{i}}_{\mathrm{\α}}-i_{\mathrm{\α}})\\ \frac{d{\hat{i}}_{\mathrm{\β}}}{dt}=-\frac{R}{L}{\hat{i}}_{\mathrm{\β}}+\frac{1}{L}{u}_{\mathrm{\β}}-\frac{1}{L}kH({\hat{i}}_{\mathrm{\β}}-i_{\mathrm{\β}})\end{array}\right.---\left(7\right)$

In formulaIt is respectively i_α、i_βEstimated value；K is sliding formwork gain.Switch functionFor S type Switch function, expression is as follows:

$\left\{\begin{array}{c}H\left({\stackrel{\‾}{i}}_{\mathrm{\α}}\right)=\frac{2}{1+\exp (-a{\stackrel{\‾}{i}}_{\mathrm{\α}})}-1\\ H\left({\stackrel{\‾}{i}}_{\mathrm{\β}}\right)=\frac{2}{1+\exp (-a{\stackrel{\‾}{i}}_{\mathrm{\β}})}-1\end{array}\right.---\left(8\right)$

In formula, a is the constant of the regulation S type switch function gradient, takes positive number；Stator current error

Mathematical model and the sliding mode observer model of motor are done difference, dynamic error estimation equation can be obtained

$\left\{\begin{array}{c}\frac{d{\stackrel{\‾}{i}}_{\mathrm{\α}}}{dt}=-\frac{R}{L}{\stackrel{\‾}{i}}_{\mathrm{\α}}+\frac{1}{L}{e}_{\mathrm{\α}}-\frac{1}{L}kH\left({\stackrel{\‾}{i}}_{\mathrm{\α}}\right)\\ \frac{d{\stackrel{\‾}{i}}_{\mathrm{\β}}}{dt}=-\frac{R}{L}{\stackrel{\‾}{i}}_{\mathrm{\β}}+\frac{1}{L}{e}_{\mathrm{\β}}-\frac{1}{L}kH\left({\stackrel{\‾}{i}}_{\mathrm{\β}}\right)\end{array}\right.---\left(9\right)$

Definition stator current error is as sliding formwork switch planeStructure sliding mode system, when system enters Sliding mode state with certain speed level off to equilibrium point time, i.e. stator current error is zero, can estimate that back-emf is

$e_{\mathrm{\α}}\≈-kH\left({\stackrel{\‾}{i}}_{\mathrm{\α}}\right)={\hat{e}}_{\mathrm{\α}},e_{\mathrm{\β}}\≈kH\left({\stackrel{\‾}{i}}_{\mathrm{\β}}\right)={\hat{e}}_{\mathrm{\β}}---\left(10\right)$

Utilize the back-emf of estimation, ask for rotor-position as follows with rotating speed formula:

$\widehat{\mathrm{\θ}}=-a\tan ({\hat{e}}_{\mathrm{\α}}/{\hat{e}}_{\mathrm{\β}})---\left(11\right)$

$\widehat{\mathrm{\ω}}=\frac{d}{dt}\widehat{\mathrm{\θ}}---\left(12\right)$

The stability analysis of above-mentioned sliding mode observer:

Definition sliding-mode surface is x=[x_α x_β]^T, in formulaWhen system runs to equilibrium point, estimate Calculating error is 0, nowObserver has the strongest robustness to system parameter variations and interference.

Definition Liapunov function

$V=\frac{1}{2}{x}^{T}x---\left(13\right)$

System stability to be ensured, it is necessary to meet

$\stackrel{\&CenterDot;}{V}=x^T\stackrel{\&CenterDot;}{x}<0,V>0---\left(14\right)$

According to (6), (9) Shi Ke get:

$V=\frac{1}{2}({{\stackrel{\&OverBar;}{i}}_{\mathrm{\&alpha;}}}^2+{{\stackrel{\&OverBar;}{i}}_{\mathrm{\&beta;}}}^2)>0---\left(15\right)$

So only needing to ensureAforementioned stable condition can be met, because of:

${\stackrel{\&CenterDot;}{x}}_{\mathrm{\&alpha;}}={\stackrel{\&CenterDot;}{\stackrel{\&OverBar;}{i}}}_{\mathrm{\&alpha;}}={\stackrel{\&CenterDot;}{\hat{i}}}_{\mathrm{\&alpha;}}-{\stackrel{\&CenterDot;}{i}}_{\mathrm{\&alpha;}}=A({\hat{i}}_{\mathrm{\&alpha;}}-i_{\mathrm{\&alpha;}})+\frac{1}{L}{e}_{\mathrm{\&alpha;}}-\frac{1}{L}kH\left({\stackrel{\&OverBar;}{i}}_{\mathrm{\&alpha;}}\right)$

${\stackrel{\&CenterDot;}{x}}_{\mathrm{\&beta;}}={\stackrel{\&CenterDot;}{\stackrel{\&OverBar;}{i}}}_{\mathrm{\&beta;}}={\stackrel{\&CenterDot;}{\hat{i}}}_{\mathrm{\&beta;}}-{\stackrel{\&CenterDot;}{i}}_{\mathrm{\&beta;}}=A({\hat{i}}_{\mathrm{\&beta;}}-i_{\mathrm{\&beta;}})+\frac{1}{L}{e}_{\mathrm{\&beta;}}-\frac{1}{L}kH\left({\stackrel{\&OverBar;}{i}}_{\mathrm{\&beta;}}\right)---\left(16\right)$

In formula: A=-R/L.Have in conjunction with (13), (16) formula:

$\stackrel{\&CenterDot;}{V}=x^T\stackrel{\&CenterDot;}{x}=A({{\stackrel{\&OverBar;}{i}}_{\mathrm{\&alpha;}}}^2+{{\stackrel{\&OverBar;}{i}}_{\mathrm{\&beta;}}}^2)+\frac{1}{L}\{{\stackrel{\&OverBar;}{i}}_{\mathrm{\&alpha;}}\&lsqb;e_a-kH\left({\stackrel{\&OverBar;}{i}}_{\mathrm{\&alpha;}}\right)\&rsqb;+{\stackrel{\&OverBar;}{i}}_{\mathrm{\&beta;}}\&lsqb;e_{\mathrm{\&beta;}}-kH\left({\stackrel{\&OverBar;}{i}}_{\mathrm{\&beta;}}\right)\&rsqb;\}---\left(17\right)$

CauseMake (17) formula less than zero, then k span is:

$k>\max \left(\right|{\hat{e}}_{\mathrm{\&alpha;}}|,|{\hat{e}}_{\mathrm{\&beta;}}\left|\right)---\left(18\right)$

If sliding formwork gain coefficient k is:

K=k_va·ω (19)

In conjunction with (6), (18) (19) formula, k_va>ψ_fJust can ensure that in this programme, sliding mode observer based on S type switch function is Stable.Along with the rising of rotating speed, S type switch function amplitude is the most linearly increasing, as shown in Figure 4.

Experimental waveform below in conjunction with Fig. 5 to Figure 11 verifies the feasibility of the present invention program.

Fig. 5 is the speed responsive contrast waveform of sliding mode observer of the present invention and tradition sliding mode observer, is respectively two in figure Under the scheme of kind, motor accelerates to 960r/min speed waveform from 480r/min, as can be seen from the figure: this programme sliding mode observer Acceleration time t₁=1740ms, the tradition sliding mode observer acceleration time is t₂=1780ms, saves 40ms, and speed responsive improves 2.35%.Being consistent with above-mentioned analysis, this programme sliding mode observer eliminates low pass filter thus has and respond speed faster Degree, solves the latency issue that tradition sliding mode observer brings.

Fig. 6 and Fig. 7 is followed successively by tradition sliding mode observer and is respectively 460r/min and 960r/ with observer rotating speed of the present invention Estimation counter potential waveform during min.Know from waveform: no matter middling speed (Fig. 6) and (Fig. 7) tradition sliding mode observer estimation at a high speed is anti- All there is substantially shake in electromotive force, the sine degree of back electromotive force of sliding mode observer of the present invention estimation is all preferable, eliminates tradition sliding formwork and sees Survey the problem that device exists shake.

Fig. 8 to Figure 11 is followed successively by tradition sliding mode observer and is respectively 460r/min and 960r/ with observer rotating speed of the present invention Electrical angle waveform during min.Known by waveform: the electricity no matter middling speed and high speed sliding mode observer of the present invention (Fig. 9 and Figure 11) are estimated AngleRelatively conventional method (Fig. 8 and Figure 10) is much smaller with the error of actual electrical angle θ；During high speed, this programme achieves zero by mistake Difference, thus demonstrate this programme high precision of electrical angle estimation when high speed.

The present invention utilizes and coordinates S type switch function to solve tradition sliding mode observer with the sliding formwork gain coefficient k of rotation speed change The shake existed and latency issue simultaneously, eliminate original low pass filter and huge angle compensation table, have algorithm letter Single, strong robustness, it is easy to the advantages such as Project Realization, the program be used in TSMC-PMSM more time system there is input unit power Factor, energy capable of bidirectional flowing, input side is without the good characteristic such as storage capacitor and excellent transmission performance.

Claims (1)

1. the permagnetic synchronous motor sliding-mode speed observer that dual stage matrix converter drives, it is characterised in that: include based on sliding formwork The motor model (1) of observer, S type switch function (2), angle calculation module (3) and angular speed calculation module (4)；By electricity Stator voltage u under the biphase rest frame of permagnetic synchronous motor that ballast structure obtains_αAnd u_βOutput with S type switch function (2) AmountWithAs the input of motor model (1) based on sliding mode observer, motor model (1) based on sliding mode observer exports Stator current observation Subtract stator actual current value i_α、i_β, stator current errorAs S type switch function (2) input, exports the back-emf estimated value under biphase rest frame after being processedWithUnder biphase rest frame Back-emf estimated valueWithFor the output of S type switch function (2), then obtain rotor position through angle calculation module (3) PutAngular velocity is obtained through angular speed calculation module (4) derivation

Described S type switch function (2) expression formula is as follows:

$\left\{\begin{array}{c}H\left(\stackrel{\&OverBar;}{i_{\mathrm{\&alpha;}}}\right)=\frac{2}{1+\exp (-a\stackrel{\&OverBar;}{i_{\mathrm{\&alpha;}}})}-1\\ H\left(\stackrel{\&OverBar;}{i_{\mathrm{\&beta;}}}\right)=\frac{2}{1+\exp (-a\stackrel{\&OverBar;}{i_{\mathrm{\&beta;}}})}-1\end{array}\right.---\left(8\right)$

In formula, a is the constant of the regulation S type switch function gradient, takes positive number；Stator current error

Described motor model (1) expression formula based on sliding mode observer is as follows,

$\left\{\begin{array}{c}\frac{d\stackrel{\&OverBar;}{i_{\mathrm{\&alpha;}}}}{dt}=-\frac{R}{L}\stackrel{\&OverBar;}{i_{\mathrm{\&alpha;}}}+\frac{1}{L}{e}_{\mathrm{\&alpha;}}-\frac{1}{L}kH\left(\stackrel{\&OverBar;}{i_{\mathrm{\&alpha;}}}\right)\\ \frac{d\stackrel{\&OverBar;}{i_{\mathrm{\&beta;}}}}{dt}=-\frac{R}{L}\stackrel{\&OverBar;}{i_{\mathrm{\&beta;}}}+\frac{1}{L}{e}_{\mathrm{\&beta;}}-\frac{1}{L}kH\left(\stackrel{\&OverBar;}{i_{\mathrm{\&beta;}}}\right)\end{array}\right.---\left(7\right)$

In formula, k is sliding formwork gain coefficient, and R, L are respectively the stator resistance of permagnetic synchronous motor, inductance, e_α、e_βFor static coordinate Back-emf under Xi；

Described S type switch function (2), using stator current error as input, is not reaching to S type switch at this stator current error The when of function upper and lower two diverter surfaces, the switching signal of output be entered as exponential relationship, error reaches defeated during diverter surface Going out equal to 1, when reaching lower diverter surface, output is equal to-1；A is the biggest, and S type switch function (2) more levels off to sign function.