CN103684179B - Compensation device and compensation method of current filtering and dead zone of permanent magnet synchronous motor - Google Patents

Abstract

The invention relates to a compensation device and a compensation method of current filtering and the dead zone of a permanent magnet synchronous motor. The input end of a position sensor is connected with the output end of the permanent magnet synchronous motor, and the output end of the position sensor is connected with a rotating speed calculation module, a coordinate transformation module and a current inverse transformation module respectively. The output value of the rotating speed calculation module is used as the input of a speed ring PI adjuster. A current sensor inputs the detected two-phase current of the permanent magnet synchronous motor to the coordinate transformation module through a summation module, meanwhile the two-phase current is input into the coordinate transformation module, the coordinate transformation module transforms the coordinate of three-phase currents and then inputs the currents to an incremental kalman filter, and the output end of the incremental kalman filter is connected with the current inverse transformation module, a q-axis current ring and a d-axis current ring. The output end of a first current ring PI adjuster and the output end of a second current ring PI adjuster are connected with an inverter through a voltage inverse transformation module, the output end of the current inverse transformation module is connected with the input end of a dead zone compensation module, the output end of the dead zone compensation module is connected with the input end of the inverter, and the output end of the inverter is connected with the input end of the permanent magnet synchronous motor.

Description

A kind of permagnetic synchronous motor current filtering and dead area compensation device and compensation method

Technical field

The present invention relates to a kind of current of electric filtering and dead area compensation device and compensation method, especially with regard to a kind of permanent magnetism Synchronous motor current filtering and dead area compensation device and compensation method.

Background technology

Permagnetic synchronous motor has the advantages that high efficiency, high power density, non-carbonate, obtains in servo occasion and extensively should With.Actual system typically all includes a certain degree of noise, and the current noise source of PMSM Servo System can To be divided into two kinds, a kind of is the white noise being caused due to non-ideal factors such as interference, sampling errors, and this is unavoidable.Separately A kind of is because system is in the state of closed-loop control, original white noise is adjusted as error originated from input, causes system Export frequent disturbance, thus causing bigger noise.For the noise of this type, rational filtering method can be taken, System white noise is filtered by feedback channel to greatest extent, it is to avoid cause the unnecessary disturbance of system output, thus reaching weakening The purpose of noise.

Low pass filter is a kind of conventional filtering method, and it has the characteristics that, and structure is simple, calculated load is little.Slide flat All filtering is exactly substantially a kind of easy low pass filter, and in servo field, it is widely used in filtering electric current, rotating speed etc. High-frequency random noises in signal.But, all there is time delay to all frequency contents in signal in principle of lowpass filter, this The time delay of sample can weaken the dynamic property of system.

Kalman filtering is a kind of modern times filtering method growing up the sixties in last century, and it is a kind of minimum variance meaning Optimum linearity method of estimation in justice.Different from principle of lowpass filter, Kalman filter has used system mathematic model, Be equivalent to and obtain more system informations, the filtering to system state amount or estimation can be realized based on Mathematical Modeling, but generation Valency is that calculated load significantly increases.PMSM Servo System typically adopts three-phase pwm voltage source inverter to drive.For Avoid two switches on same brachium pontis to simultaneously turn on, typically take the mode of insertion Dead Time to ensure to switch at one Before conducting, another switch has been switched off.The insertion in dead band is equivalent to the interference voltage being superimposed a cycle pulsation, this Interference voltage can cause phase current distortion and then cause motor to export the pulsation of electromagnetic torque.

In order to obtain the more preferable phase current waveform of sine degree, the shadow of deadband eliminating effect typically by way of dead area compensation Ring.Because the interference voltage that dead band causes has close ties with the polarity of phase current, phase current polarity judges that error leads to Mistake compensation can cause electric current that bigger distortion, the therefore detection that it is critical only that phase current zero crossing of dead area compensation occur.Directly Connect and judge that phase current polarity is easily affected by sampling noiset according to the detected value that a/d is converted to, the several of compensation by mistake occur Rate is than larger.Conventional method is according to the position judgment phase current polarity of output voltage vector, it is to avoid current sample noise brings Adverse effect, the strategy that only wherein one phase output voltage need to be compensated is proposed in specific currents region simultaneously, but Steady-state process is only applicable to the computational methods of " angle between voltage vector and induced electromotive force ", for rotating speed and electric current etc. Operating mode is in the servo-drive system of frequent fluctuation inapplicable.

During using digital control approach, there is a delayed time delay of bat in the applying of controlled quentity controlled variable.In this case, if still to work as The current status in front cycle are as the foundation judging phase current polarity, then the compensation to dead band also can postpone a bat.If In current period, current polarity has occurred and that change, and because digital control one claps delayed impact, offset voltage is in current period Interior can not be made an immediate response, just can must make adjustment when next cycle the soonest.In this case, dead in current period Area compensates and is equivalent to compensate by mistake.For bat lag issues of dead area compensation, research is less at present.

Content of the invention

For the problems referred to above, it is an object of the invention to provide a kind of effective electricity weakening current noise and suppressing dead band to cause The permagnetic synchronous motor current filtering of magnetic torque pulsation and dead area compensation device and compensation method.

For achieving the above object, the present invention takes technical scheme below: a kind of permagnetic synchronous motor current filtering and dead band Compensation device it is characterised in that: it include position sensor, permagnetic synchronous motor, rotating speed computing module, coordinate transformation module, Electric current inverse transform block, speed ring pi adjuster, current sensor, summation module, increment type Kalman filter, the first electric current Ring pi adjuster 1, voltage inverse transform block, the second electric current loop pi adjuster, inverter and dead area compensation module；Described coordinate becomes Die change block, increment type Kalman filter and the first electric current loop pi adjuster constitute q shaft current ring；Described coordinate transformation module, Increment type Kalman filter and the second electric current loop pi adjuster constitute d shaft current ring, described q shaft current ring and d shaft current ring Constitute electric current loop；The input of described position sensor connects the output end of described permagnetic synchronous motor, described position sensor Output end connect described rotating speed computing module, described coordinate die change block and electric current inverse transform block respectively, by the electricity collecting Angle, θ transmits to described rotating speed computing module, described coordinate die change block and electric current inverse transform block；Described rotating speed computing module is defeated The rotational speed omega going out as negative-feedback, and with given rotating speed command value ω^*After taking difference, defeated as described speed ring pi adjuster Enter；Described current sensor connects the stator of described permagnetic synchronous motor, by the three-phase of the permanent-magnetic synchronous motor stator detecting Biphase current in electric current takes through the summation of described summation module after bearing and inputs described coordinate transformation module；Described current sensor is same When also described biphase current is inputted described coordinate transformation module, described three-phase current carries out dq seat by described coordinate transformation module Described increment type Kalman filter, q shaft current detected value i is inputted after mark conversion_qWith d shaft current detected value i_dThrough described increment After formula Kalman filter is processed, by q shaft current predictive filtering value i_{q_pre}Input described q shaft current ring and electric current inverse transformation respectively Module, by described d shaft current predictive filtering value i_{d_pre}Input described d shaft current ring and electric current inverse transform block respectively；Described q axle Current forecasting filter value i_{q_}As q shaft current ring negative-feedback, the output with described speed ring pi adjuster is compared, and fiducial value inputs Obtain q shaft voltage to described first electric current loop pi adjuster, q shaft voltageTransmit to described voltage inverse transform block；Described d Shaft current detected value i_{d_}As d shaft current ring negative-feedback and previously given electric currentRelatively, fiducial value is input to described second Electric current loop pi adjuster obtains d shaft voltage, d shaft voltageTransmit to described voltage inverse transform block；Described voltage inverse transformation The output end of module connects the input of described inverter；The output end of described electric current inverse transform block connects described dead area compensation The input of module, the output end of described dead area compensation module connects the input of described inverter, the output of described inverter End connects the input of described permagnetic synchronous motor.

Permagnetic synchronous motor current filtering based on a kind of permagnetic synchronous motor current filtering and dead area compensation device and dead Area's compensation method, comprises the following steps: 1) current sensor is by the permagnetic synchronous motor detecting threephase stator electric current i_a、i_bWith i_cInput to coordinate transformation module, the coordinate transform of abc/ α β is carried out to it, the electric current obtaining under two-phase rest frame divides Amount i_α、i_β:

$\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_{\mathrm{\β}}\end{array}\right]=\sqrt{\frac{2}{3}}\left[\begin{array}{ccc}1& -\frac{1}{2}& -\frac{1}{2}\\ 0& \frac{\sqrt{3}}{2}& \frac{\sqrt{3}}{2}\end{array}\right]\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_b\\ i_c\end{array}\right],$ In formula, i_cFor i_a、i_bThe negative value of sum；

2) in coordinate transformation module, electrical angle θ that the permanent-magnetic synchronous motor rotor according to receiving rotates through, to two-phase Current component i under rest frame_α、i_βCarry out α β/dq coordinate transform again, obtain the electricity under two-phase synchronous rotary dq coordinate system Stream detected value i_d、i_q:

$\left[\begin{array}{c}{i}_d\\ i_q\end{array}\right]=\left[\begin{array}{cc}\cos \mathrm{\θ}& \sin \mathrm{\θ}\\ -\sin \mathrm{\θ}& \cos \mathrm{\θ}\end{array}\right]\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_{\mathrm{\β}}\end{array}\right],$ In formula, the electrical angle that θ rotates through for permanent-magnetic synchronous motor rotor, passed by position Sensor obtains；

3) electrical angle θ that permanent-magnetic synchronous motor rotor rotates through inputs to rotating speed computing module, electrical angle θ is carried out micro- Point, obtain speed feedback value ω；Speed feedback value ω and previously given rotational speed command value ω^*As speed ring pi adjuster Input, obtains current instruction value through calculation process；4) current detection value i_q、i_dIt is input in increment type Kalman filter, D shaft current predictive filtering value i is exported by increment type Kalman filter_{d_pre}With q shaft current predictive filtering value i_{q_pre}；5) electric current Command valuePreviously given electric currentRespectively with d shaft current predictive filtering value i_{d_pre}With q shaft current predictive filtering value i_{q_pre}Than Relatively, fiducial value, respectively as the input of the first electric current loop pi adjuster, the second electric current loop pi adjuster, is distinguished through calculation process Obtain the first electric current loop pi adjuster, the reference voltage of the second electric current loop adjuster output；6) d shaft current predictive filtering Value i_{d_pre}, q shaft current predictive filtering value i_{q_pre}The electrical angle rotating through with the permanent-magnetic synchronous motor rotor of position sensor output θ is separately input to electric current inverse transform block, exports three-phase predicted current i by electric current inverse transform block_{a_pre}、i_{b_pre}And i_{c_pre}；7) Three-phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}Input dead area compensation module, dead area compensation module is according to three-phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}Polarity export corresponding offset voltage；8) reference voltageInput voltage inverse transform block, Voltage inverse transform block exports three-phase voltage u_a, u_b, u_c, with three-phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}Corresponding compensation Voltage respectively with three-phase voltage u_a, u_b, u_cInverter is inputted, inverter exports corresponding three-phase voltage to permanent-magnet synchronous after superposition Motor, drives permagnetic synchronous motor work.

In described step 4), increment type Kalman filter is to current detection value i_d、i_qProcess comprise the following steps:

(1) under synchronous rotating frame, the stator d axle of permagnetic synchronous motor, q shaft voltage equation are:

u_d=ri_d+l_ddi_d/dt-ωl_qi_q, u_q=ri_q+l_qdi_q/dt+ωl_di_d+ωψ_f, wherein u_d、u_qIt is respectively stator d, q Shaft voltage, i_d、i_qIt is respectively stator d, q shaft current, r is stator resistance, l_d、l_qIt is respectively stator d, q axle inductance, ψ_fFor permanent magnet Magnetic linkage, ω is rotor speed；(2) according to the stator q shaft voltage equation in step (1), in current period (k) t_sWith a upper cycle (k-1)t_sInside set up the discrete voltage equation of permagnetic synchronous motor respectively:

u_q(k)=r_e(i_q(k)+i_{q_pre}(k+1))/2+l_e(i_{q_pre}(k+1)-i_q(k))/t_s+ω(l_di_d+ψ_f),

u_q(k-1)=r(i_q(k)+i_q(k-1))/2+l_q(i_q(k)-i_q(k-1))/t_s ⁺ω(l_di_d+ψ_f),

Wherein i_{q_pre}(k+1) it is the predicted value to next start time in cycle q shaft current in current period, abbreviation electric current is pre- Measured value, i_qK () is the current detection value of current period, i_q(k-1) a upper periodic permanent magnet synchronous motor stator q shaft current detected value, t_sFor controlling cycle, u_qK () is current period stator q shaft voltage, u_q(k-1) it is a upper cycle stator q shaft voltage, r_e、l_eRespectively It is to permanent-magnetic synchronous motor stator resistance r, stator q axle inductance l_qEstimate；(3) ignore the change of the voltage term related to rotating speed Change, two formula in step (2) are subtracted each other, obtains the simplification current increment formula of permagnetic synchronous motor, because r_eIt is much smaller than l_e/t_s, therefore ignore the impact of r, obtain predicted value i to next start time in cycle d shaft current in current period_{d_pre}(k+ 1), and by current increment formula change into matrix form:

$x_k=\left[\begin{array}{c}{i}_q\left(k\right)\\ i_q(k-1)\end{array}\right],x_{k-1}=\left[\begin{array}{c}{i}_q(k-1)\\ i_q(k-2)\end{array}\right],f_{k-1}=\begin{array}{c}\left[\begin{array}{cc}2& -1\\ 1& 0\end{array}\right]\end{array}\begin{array}{c},b_{k-1}=\left[\begin{array}{c}{t}_s/l_q\\ 0\end{array}\right],c={\left[\begin{array}{c}1\\ 0\end{array}\right]}^t\end{array};$

(4) Mathematical Modeling of increment type Kalman filter is set up according to the current increment formula of step (3) matrix form For:

$\left\{\begin{array}{c}{x}_k=f_{k-1}{x}_{k-1}+b_{k-1}{u}_{k-1}+w\\ y_k=c{x}_k+v\end{array}\right.,$

Wherein, w is input noise vector, and v is output noise vector；x_k、x_k-1For system mode vector, y_kFor system output Vector, u_k-1For dominant vector；f_k-1、b_k-1, c be coefficient matrix；

(5) Mathematical Modeling according to increment type Kalman filter, is iterated to its correlated variables, obtains optimal estimation Value

In described step (5), described optimal estimation valueComputational methods comprise the following steps:

1. calculate prior estimate vector valueWith corresponding error matrix

${\hat{x}}_k^{-}=f_{k-1}{\hat{x}}_{k-1}{b}_{k-1}{u}_{k-1},p_k^{-}=f_{k-1}{p}_{k-1}{p}_{k-1}^t+q_{k-1},$

Wherein, q_k-1For noise matrix q_k-1,Optimal estimation vector value for system state variablesIn (k-1) week The state vector of phase,For kth cycle prior estimate vector, it is an intermediate variable,For kth cycle prior estimate error square Battle array, also for intermediate variable matrix, p_k-1For system (k-1) cycle error matrix；

2. calculate gain matrix k_k: $k_k=p_k^{-}{c}^t{(c{p}_k^{-}{c}^t+r_{k-1})}^{-1};$

3. computing system is in the optimal estimation value of kth periodic system state variable

Wherein ${\hat{x}}_k=\left[\begin{array}{c}{i}_{q\_}\left(k\right)\\ i_{q\_}(k-1)\end{array}\right],$ i_{q_}(k-1) it is permanent-magnetic synchronous motor rotor (k-1) current detection value i_qOptimum Estimate, i_{q_}K () is permanent-magnetic synchronous motor rotor in kth periodic current detected value i_qOptimal estimation value；

4. calculate the error matrix p in kth cycle_kOptimal estimation value:, wherein, q_k-1, r is respectively The covariance matrix of noise w, v, error matrix p_kFor the error matrix of the optimal estimation value in estimation process, changed by multiple Generation, error matrix p_kEventually converge to null matrix.

In described step 6), in described electric current inverse transform block, processing procedure comprises the following steps:

1. predict next periodic permanent magnet synchronous electric motor rotor coordinate transform angle, θ_pre, due to permagnetic synchronous motor machinery Time constant is much larger than the state of electrical time constant operation then it is assumed that motor remains a constant speed at short notice, i.e. permanent-magnet synchronous The angle, θ that rotor turned within next cycle with current period is consistent；

2. combine the predictive filtering value of dq shaft current, by coordinate transform, obtain the prediction of the three-phase current in next cycle Value i_{a_pre}、i_{b_pre}And i_{c_pre}For:

$\left[\begin{array}{c}{i}_{a\_\mathrm{pre}}\\ i_{b\_\mathrm{pre}}\\ i_{c\_\mathrm{pre}}\end{array}\right]=\begin{array}{c}\left[\begin{array}{cc}\cos {\mathrm{\θ}}_{\mathrm{pre}}& -\sin {\mathrm{\θ}}_{\mathrm{pre}}\\ \cos ({\mathrm{\θ}}_{\mathrm{pre}}-\frac{2\mathrm{\π}}{3})& -\sin ({\mathrm{\θ}}_{\mathrm{pre}}-\frac{2\mathrm{\π}}{3})\\ \mathrm{ocs}({\mathrm{\θ}}_{\mathrm{pre}}+\frac{2\mathrm{\π}}{3})& -\sin ({\mathrm{\θ}}_{\mathrm{pre}}+\frac{2\mathrm{\π}}{3})\end{array}\right]\end{array}\left[\begin{array}{c}{i}_{d\_\mathrm{pre}}\\ i_{q\_\mathrm{pre}}\end{array}\right],$

And predicted value i of next cycle three-phase current is calculated according to above formula_{a_pre}、i_{b_pre}And i_{c_pre}.

In described step 7), described dead area compensation comprises the following steps:

1. dead area compensation module is according to next cycle three-phase predicted current i receiving_{a_pre}、i_{b_pre}And i_{c_pre}, under obtaining Relevant voltage error delta u that one cycle three-phase predicted current produces respectively_a、δu_bWith δ u_c:

${\mathrm{\δu}}_a=\frac{t_d+t_{\mathrm{on}}-t_{\mathrm{off}}}{t_s}{v}_{\mathrm{dc}}\mathrm{sign}\left(i_{a\_\mathrm{pre}}\right),{\mathrm{\δu}}_b=\frac{t_d+t_{\mathrm{on}}-t_{\mathrm{off}}}{t_s}{v}_{\mathrm{dc}}\mathrm{sign}\left(i_{b\_\mathrm{pre}}\right),{\mathrm{\δu}}_c=\frac{t_d+t_{\mathrm{on}}-t_{\mathrm{off}}}{t_s}{v}_{\mathrm{dc}}\mathrm{sign}\left(i_{c\_pre}\right),$

Sign () be predicted current polarity, predicted current value > 0 when, sign () value be 1, otherwise for -1；

2. by three-phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}The voltage error δ u producing_a、δu_bWith δ u_cTake negative respectively Value, obtains and three-phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}Corresponding offset voltage.

Due to taking above technical scheme, it has the advantage that the 1, present invention adopts increment type Kalman to filter to the present invention The dq shaft current filtering method of ripple device, replaces the current detection value of reality defeated as the feedback of electric current loop adjuster with filter value Enter, the interference of sampling noiset can be eliminated.2nd, the system based on the current filtering method of increment type Kalman filter for the present invention State equation order is only second order, and calculated load substantially reduces, and avoids the estimation to the voltage term relevant with rotating speed simultaneously, is System complexity and sensitivity to parameter substantially reduce.3rd, the present invention is by the voltage error causing with dead band in the superposition of inverter link The voltage of contrast, being capable of effectively deadband eliminating interference.4th, the present invention can be in current period using incremental forecasting method Calculate next cycle dq shaft current in advance, therefore, it is possible to eliminate a delayed time delay of bat of digital control approach.5th, the present invention will Dq shaft current filter value makees closed-loop control, can reduce noise, reduce the pulsation of dq shaft voltage；With obtain with prediction after filtering Phase current predicted value makees dead area compensation, advantageously reduces and compensates because of the mistake that phase current polarity erroneous judgement leads to, eliminates a bat simultaneously The impact of delayed time delay.The present invention is applied to permagnetic synchronous motor SERVO CONTROL field.

Brief description

Fig. 1 is the PMSM Servo System overall structure diagram that the present invention adopts；

Fig. 2 is current sample time diagram of the present invention；

Fig. 3 is the impact schematic diagram to stator phase voltage for the prior art dead band；

Fig. 4 is the relation schematic diagram of prior art permagnetic synchronous motor dq shaft voltage error and rotor electrical angle；

Fig. 5 is current filtering of the present invention and dead-zone compensation method schematic diagram；

Fig. 6 is the filter effect contrast schematic diagram using distinct methods to q shaft current, and Fig. 6 (a) is using moving average filter The filter effect schematic diagram to q shaft current for the ripple device, Fig. 6 (b) is to q shaft current using increment type Kalman filter of the present invention Filter effect schematic diagram；

Fig. 7 be using prior art with using current filtering of the present invention stable state when dq shaft voltage and dq shaft current ripple Shape contrast schematic diagram, wherein, Fig. 7 (a) is using prior art and the dq shaft voltage waveform during stable state being filtered using the present invention Contrast schematic diagram, Fig. 7 (b) is to be shown using the comparison of wave shape of prior art and the dq shaft current during stable state being filtered using the present invention It is intended to；

Fig. 8 is using stator phase currents i during current filtering of the present invention_a、i_bPredicted value and detected value schematic diagram；

Fig. 9 is using the present invention and the stator phase currents i being provided without during the present invention under three kinds of rotating speeds_a、i_b, q shaft current i_q, q shaft voltage u_qComparison of wave shape schematic diagram, wherein Fig. 9 (a) are using this during 1000rpm for permanent-magnetic synchronous motor rotor rotating speed Invent and using stator phase currents i during prior art_a、i_b, q shaft current i_q, q shaft voltage u_qComparison of wave shape schematic diagram, Fig. 9 (b) is Permanent-magnetic synchronous motor rotor rotating speed is for employing present invention during 200rpm with using stator phase currents i during prior art_a、i_b, q axle Electric current i_q, q shaft voltage u_qComparison of wave shape schematic diagram, Fig. 9 (c) is using this during 50rpm for permanent-magnetic synchronous motor rotor rotating speed Bright and using prior art when stator phase currents i_a、i_b, q shaft current i_q, q shaft voltage u_qComparison of wave shape schematic diagram；

Figure 10 is that permanent-magnetic synchronous motor rotor rotating speed is provided without the present invention and using dq shaft current during the present invention for 1200rpm With the Steady Experimental comparison of wave shape schematic diagram of dq shaft voltage, Figure 10 (a) is dq shaft current and dq shaft voltage when being provided without the present invention Steady Experimental waveform diagram, Figure 10 (b) is to be shown using the Steady Experimental waveform of dq shaft current during the present invention and dq shaft voltage It is intended to；

Figure 11 be permagnetic synchronous motor rotating speed for 1200rpm when be provided without the present invention and using the present invention when permanent magnet synchronous electric Machine stator monophase current experimental waveform contrast schematic diagram, Figure 11 (a) is permanent-magnet synchronous when being provided without dead-zone compensation method of the present invention Motor stator monophase current waveform diagram, Figure 11 (b) is using permanent-magnetic synchronous motor stator during dead-zone compensation method of the present invention Monophase current waveform diagram；

Figure 12 be permanent-magnetic synchronous motor rotor rotating speed for 500rpm when be provided without the present invention with using the present invention dq axle electricity Stream and the Steady Experimental comparison of wave shape schematic diagram of dq shaft voltage, Figure 12 (a) is dq shaft current and dq axle electricity when being provided without the present invention The Steady Experimental waveform diagram of pressure, Figure 12 (b) is the Steady Experimental waveform using dq shaft current during the present invention and dq shaft voltage Schematic diagram；

Figure 13 be permagnetic synchronous motor rotating speed for 500rpm when be provided without dead-zone compensation method of the present invention and adopt the present invention Permanent-magnetic synchronous motor stator monophase current experimental waveform contrast schematic diagram during dead-zone compensation method；

Figure 14 is determining when permagnetic synchronous motor rotating speed is provided without dead-zone compensation method of the present invention in two kinds of low speed respectively Sub- monophase current experimental waveform schematic diagram, Figure 14 (a) is that permagnetic synchronous motor rotating speed is during 170rpm and to be provided without the present invention dead Stator monophase current experimental waveform schematic diagram during area's compensation method, Figure 14 (b) be permagnetic synchronous motor rotating speed be 80rpm when and It is provided without stator monophase current experimental waveform schematic diagram during dead-zone compensation method of the present invention；

Specific embodiment

With reference to the accompanying drawings and examples the present invention is described in detail.

As shown in figure 1, the present invention includes position sensor 1, permanent magnet synchronous electric taking PMSM Servo System as a example Machine (pmsm) 2, rotating speed computing module 3, coordinate transformation module 4, electric current inverse transform block 5, speed ring pi adjuster 6, electric current pass Sensor 7, summation module 8, increment type Kalman filter 9, the first electric current loop pi adjuster 10, voltage inverse transform block 11, Two electric current loop pi adjusters 12, inverter 13 and dead area compensation module 14.Wherein coordinate transformation module 4, increment type Kalman filter Ripple device 9 and the first electric current loop pi adjuster 10 constitute q shaft current ring；Coordinate transformation module 4, increment type Kalman filter 9 and Second electric current loop pi adjuster 12 constitutes d shaft current ring, and q shaft current ring and d shaft current ring constitute electric current loop.

The input of position sensor 1 connects the output end of permagnetic synchronous motor 2, and the output end of position sensor 1 is respectively Connect rotating speed computing module 3, coordinate die change block 4 and electric current inverse transform block 5, electrical angle θ collecting is transmitted to tachometer Calculate module 3, coordinate die change block 4 and electric current inverse transform block 5.Rotating speed computing module 3 output rotational speed omega as negative-feedback, and with Given rotating speed command value ω^*After taking difference, as the input of speed ring pi adjuster 6.Current sensor 7 connects permanent magnet synchronous electric The stator of machine 2, for detecting the biphase current i in the three-phase current of permagnetic synchronous motor 2 stator_aAnd i_b, then by biphase current i_aAnd i_bInput summation module 8, summation module 8 is to biphase current i_aWith i_bAnd take and obtain third phase electric current i after negative value_c, and will Third phase electric current i_cInput coordinate conversion module 4.Current sensor 7 is simultaneously also by biphase current i_aAnd i_bInput coordinate becomes die change Block 4, coordinate transformation module 4 is according to electrical angle θ receiving by three-phase current i_a、i_bAnd i_cCarry out output q axle electricity after coordinate transform Stream detected value i_qWith d shaft current detected value i_d, and through increment type Kalman filter 9 by q shaft current detected value i_qWith d shaft current Detected value i_dAfter predictive filtering is processed, by q shaft current predictive filtering value i_{q_pre}Input q shaft current ring and electric current contravariant die change respectively Block 5, by d shaft current predictive filtering value i_{d_pre}Input d shaft current ring and electric current inverse transform block 5 respectively.Q shaft current predictive filtering Value i_{q_}As q shaft current ring negative-feedback, the output with speed ring pi adjuster 6 is current-orderCompare, fiducial value inputs Obtain q shaft voltage to the first electric current loop pi adjuster 10, the first electric current loop pi adjuster 10 is by q shaft voltageTransmit to voltage Inverse transform block 11；D shaft current detected value i_{d_}As d shaft current ring negative-feedback and previously given electric currentCompare, compare Value is input to the second electric current loop pi adjuster 12 and obtains d shaft voltage, the second electric current loop pi adjuster 12 is by d shaft voltageTransmission To voltage inverse transform block 11.The output end of voltage inverse transform block 11 connects the input of inverter 13；Electric current contravariant die change The output end of block 5 connects the input of dead area compensation module 14, and the output end of dead area compensation module 14 connects the defeated of inverter 13 Enter end, the output end of inverter 13 connects the input of permagnetic synchronous motor 2.

The permagnetic synchronous motor current filtering of the present invention and dead-zone compensation method comprise the following steps:

1) as shown in figure 1, current sensor 7 is by the permagnetic synchronous motor detecting 2 threephase stator electric current i_a、i_bAnd i_cDefeated Enter to coordinate transformation module 4, it is carried out with three-phase/two-phase coordinate transform, that is, the coordinate transform of abc/ α β, obtains two-phase static Current component i under coordinate system_α、i_β:

$\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_{\mathrm{\β}}\end{array}\right]=\sqrt{\frac{2}{3}}\left[\begin{array}{ccc}1& -\frac{1}{2}& -\frac{1}{2}\\ 0& \frac{\sqrt{3}}{2}& \frac{\sqrt{3}}{2}\end{array}\right]\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_b\\ i_c\end{array}\right],$

In formula, i_cFor i_a、i_bThe negative value of sum.

2) in coordinate transformation module 4, electrical angle θ that permagnetic synchronous motor 2 rotor according to receiving rotates through, to two Current component i under phase rest frame_α、i_βCarry out static-rotating coordinate transformation again, that is, α β/dq coordinate transform, obtains two-phase Current detection value i under synchronous rotary dq coordinate system_d、i_q:

$\left[\begin{array}{c}{i}_d\\ i_q\end{array}\right]=\left[\begin{array}{cc}\cos \mathrm{\θ}& \sin \mathrm{\θ}\\ -\sin \mathrm{\θ}& \cos \mathrm{\θ}\end{array}\right]\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_{\mathrm{\β}}\end{array}\right],$

In formula, the electrical angle that θ rotates through for permagnetic synchronous motor 2 rotor, obtained by position sensor 1.

3) electrical angle θ that permagnetic synchronous motor 2 rotor rotates through inputs to rotating speed computing module 3, and electrical angle θ is carried out Differential, obtains speed feedback value ω；Speed feedback value ω and previously given rotational speed command value ω^*As speed ring pi adjuster 6 input, obtains current instruction value through calculation process

4) current detection value i_q、i_dIt is input in increment type Kalman filter 9, exported by increment type Kalman filter 9 D shaft current predictive filtering value i_{d_pre}With q shaft current predictive filtering value i_{q_pre}；

5) current instruction valuePreviously given electric currentRespectively with d shaft current predictive filtering value i_{d_pre}Pre- with q shaft current Survey filter value i_{q_pre}Relatively, fiducial value respectively as the first electric current loop pi adjuster 10, the second electric current loop pi adjuster 12 defeated Enter, respectively obtain the output of the first electric current loop pi adjuster 10, the second electric current loop pi adjuster 12, i.e. reference through calculation process Voltage

6) d shaft current predictive filtering value i_{d_pre}, q shaft current predictive filtering value i_{q_pre}Permanent magnetism with position sensor 1 output Electrical angle θ that synchronous motor 2 rotor rotates through is separately input to electric current inverse transform block 5, exports three by electric current inverse transform block 5 Phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}；

7) three-phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}Input dead area compensation module 14, dead area compensation module 14 is according to three Phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}Polarity export corresponding offset voltage；

8) reference voltageInput voltage inverse transform block 11, voltage inverse transform block 11 exports three-phase voltage u_a, u_b, u_c, with three-phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}Corresponding offset voltage respectively with three-phase voltage u_a, u_b, u_cSuperposition Input inverter 13 afterwards, inverter 13 exports corresponding three-phase voltage to permagnetic synchronous motor 2, drives permagnetic synchronous motor 2 work Make.

In above-mentioned steps 4) in, increment type Kalman filter 9 is to current detection value i_d、i_qProcess comprise the following steps:

(1) under synchronous rotating frame, the stator d axle of permagnetic synchronous motor 2, q shaft voltage equation are:

u_d=ri_d+l_ddi_d/dt-ωl_qi_q, (1)

u_q=ri_q+l_qdi_q/dt+ωl_di_d+ωψ_f, (2)

Wherein u_d、u_qIt is respectively stator d, q shaft voltage, i_d、i_qIt is respectively stator d, q shaft current, r is stator resistance, l_d、l_q It is respectively stator d, q axle inductance, ψ_fFor permanent magnet flux linkage, ω is rotor speed.

(2) according to the stator q shaft voltage equation in step (1), in current period kt_sWith a upper cycle (k-1) t_sInterior difference Set up the discrete voltage equation of permagnetic synchronous motor 2:

u_q(k)=r_e(i_q(k)+i_{q_pre}(k+1))/2+l_e(i_{q_pre}(k+1)-i_q(k))/t_s+ω(l_di_d+ψ_f), (3)

u_q(k-1)=r(i_q(k)+i_q(k-1))/2+l_q(i_q(k)-i_q(k-1))/t_s+ω(l_di_d+ψ_f), (4)

Wherein i_{q_pre}(k+1) it is the predicted value to next start time in cycle q shaft current in current period, abbreviation electric current is pre- Measured value, i_qK () is the current detection value of current period, i_q(k-1) a upper periodic permanent magnet synchronous motor stator q shaft current detected value, t_sFor controlling cycle, u_qK () is current period stator q shaft voltage, u_q(k-1) it is a upper cycle stator q shaft voltage, r_e、l_eRespectively It is to permanent-magnetic synchronous motor stator resistance r, stator q axle inductance l_qEstimate, current sample sequential is as shown in Figure 2.

(3) ignore the change of the voltage term related to rotating speed, formula (3) is subtracted each other with formula (4), obtains permanent magnet synchronous electric The current increment formula of machine 2:

$i_{q\_\mathrm{pre}}(k+1)=\frac{u_q\left(k\right)-u_q(k-1)+\frac{l_e}{t_s}({2i}_q\left(k\right)-i_q(k-1))+\frac{r_e}{2}{i}_q(k-1)}{\frac{r_e}{2}+\frac{l_e}{t_s}},---\left(5\right)$

Because r_eMuch smaller than l_e/t_s, therefore can ignore the impact of r, after simplified style (5), obtain the q of permagnetic synchronous motor 1 Shaft current predicted value is:

$i_{q\_\mathrm{pre}}(k+1)=\frac{t_s}{l_e}(u_q\left(k\right)-u_q(k-1))+({2i}_q\left(k\right)-i_q(k-1)),---\left(6\right)$

Predicted value i to next start time in cycle d shaft current in current period can be drawn in the same manner_{d_pre}, formula (6) is write Coefficient matrix is become to be followed successively by,

$x_k=\left[\begin{array}{c}{i}_q\left(k\right)\\ i_q(k-1)\end{array}\right],$

$x_{k-1}=\left[\begin{array}{c}{i}_q(k-1)\\ i_q(k-2)\end{array}\right],$

$f_{k-1}=\left[\begin{array}{cc}2& -1\\ 1& 0\end{array}\right],$

$b_{k-1}=\left[\begin{array}{c}{t}_s/l_q\\ 0\end{array}\right],$

$c={\left[\begin{array}{c}1\\ 0\end{array}\right]}^t;$

(4) Mathematical Modeling of increment type Kalman filter 9 is set up according to the current increment formula of step (3) matrix form For:

$\left\{\begin{array}{c}{x}_k=f_{k-1}{x}_{k-1}+b_{k-1}{u}_{k-1}+w\\ y_k=c{x}_k+v\end{array}\right.,---\left(9\right)$

Wherein: w is input noise (system noise) vector, v is output noise (measurement noise) vector；x_k、x_k-1For system State vector, y_kFor system output vector, u_k-1For dominant vector；f_k-1、b_k-1, c be coefficient matrix, and x_k、x_k-1、u_k-1、f_k-1、 b_k-1, c take from the value in step (3).

(5) Mathematical Modeling according to increment type Kalman filter 9, is iterated to its correlated variables, obtains optimum and estimates EvaluationIt comprises the steps:

1. calculate prior estimate vector valueWith corresponding error matrix

${\hat{x}}_k^{-}=f_{k-1}{\hat{x}}_{k-1}{b}_{k-1}{u}_{k-1},---\left(10\right)$

$p_k^{-}=f_{k-1}{p}_{k-1}{f}_{k-1}^t+q_{k-1},---\left(11\right)$

Wherein, noise matrix q_k-1Choose relevant with site environment, its selection does not typically interfere with final effect, only meeting The speed of impact convergence,Optimal estimation vector value for system state variablesIn the state vector in (k-1) cycle, and Optimal estimation vector valueInitial value can randomly select, its initial value choose do not interfere with final optimal estimation value,For Kth cycle prior estimate vector, is an intermediate variable,For kth cycle prior estimate error matrix, also for intermediate variable square Battle array, p_k-1For system (k-1) cycle error matrix.

2. calculate gain matrix k_k:

$k_k=p_k^{-}{c}^t{({\mathrm{cp}}_k^{-}{c}^t+r_{k-1})}^{-1},---\left(12\right)$

3. computing system is in the optimal estimation value of kth periodic system state variable

${\hat{x}}_k={\hat{x}}_k^{-}+k_k(y_k-c{\hat{x}}_k^{-}),---\left(13\right)$

Wherein ${\hat{x}}_k=\left[\begin{array}{c}{i}_{q\_}\left(k\right)\\ i_{q\_}(k-1)\end{array}\right],$ i_{q_}(k-1) it is permagnetic synchronous motor 2 rotor (k-1) current detection value i_qOptimum Estimate, i_{q_}K () is permagnetic synchronous motor 2 rotor in kth periodic current detected value i_qOptimal estimation value；

4. calculate the error matrix p in kth cycle_kOptimal estimation value:

$p_k=p_k^{-}-k_{k}c{p}_k^{-},---\left(14\right)$

Wherein, q_k-1, r be respectively noise w, v covariance matrix, error matrix p_kFor the optimal estimation in estimation process The error matrix of value, by successive ignition, error matrix p_kEventually converge to null matrix.

In above-mentioned steps 6) in, in electric current inverse transform block 5, processing procedure comprises the steps:

1. predict next periodic permanent magnet synchronous electric motor rotor coordinate transform angle, θ_pre, due to permagnetic synchronous motor machinery Time constant is much larger than the state of electrical time constant operation it is believed that motor remains a constant speed at short notice, and that is, permanent magnetism is same The angle, θ that step rotor turned within next cycle with current period is consistent；

2. combine the predictive filtering value of dq shaft current, by coordinate transform, obtain the prediction of the three-phase current in next cycle Value i_{a_pre}、i_{b_pre}And i_{c_pre}, as shown in formula (19):

$\left[\begin{array}{c}{i}_{a\_\mathrm{pre}}\\ i_{b\_\mathrm{pre}}\\ i_{c\_\mathrm{pre}}\end{array}\right]=\begin{array}{c}\left[\begin{array}{cc}\cos {\mathrm{\θ}}_{\mathrm{pre}}& -\sin {\mathrm{\θ}}_{\mathrm{pre}}\\ \cos ({\mathrm{\θ}}_{\mathrm{pre}}-\frac{2\mathrm{\π}}{3})& -\sin ({\mathrm{\θ}}_{\mathrm{pre}}-\frac{2\mathrm{\π}}{3})\\ \mathrm{ocs}({\mathrm{\θ}}_{\mathrm{pre}}+\frac{2\mathrm{\π}}{3})& -\sin ({\mathrm{\θ}}_{\mathrm{pre}}+\frac{2\mathrm{\π}}{3})\end{array}\right]\end{array}\left[\begin{array}{c}{i}_{d\_\mathrm{pre}}\\ i_{q\_\mathrm{pre}}\end{array}\right],---\left(19\right)$

Calculate predicted value i of next cycle three-phase current according to formula (19)_{a_pre}、i_{b_pre}And i_{c_pre}.

In above-mentioned steps 7) in, dead area compensation comprises the following steps:

1. dead area compensation module 14 is according to next cycle three-phase predicted current i receiving_{a_pre}、i_{b_pre}And i_{c_pre}, obtain Relevant voltage error delta u that next cycle three-phase predicted current produces respectively_a、δu_bWith δ u_c, δ u_aFor predicted current i_{a_pre}Produce Raw voltage error, sign (i_{a_pre}) it is predicted current i_{a_pre}Polarity, i_{a_pre}> 0 when, sign (i_{a_pre}) value be 1, otherwise For -1.

${\mathrm{\δu}}_a=\frac{t_d+t_{\mathrm{on}}-t_{\mathrm{off}}}{t_s}{v}_{\mathrm{dc}}\mathrm{sign}\left(i_{a\_\mathrm{pre}}\right),---\left(20\right)$

Predicted current i can be obtained in the same manner_{b_pre}And i_{c_pre}The voltage error δ u producing_bWith δ u_c；

${\mathrm{\δu}}_b=\frac{t_d+t_{\mathrm{on}}-t_{\mathrm{off}}}{t_s}{v}_{\mathrm{dc}}\mathrm{sign}\left(i_{b\_\mathrm{pre}}\right),---\left(21\right)$

${\mathrm{\δu}}_c=\frac{t_d+t_{\mathrm{on}}-t_{\mathrm{off}}}{t_s}{v}_{\mathrm{dc}}\mathrm{sign}\left(i_{c\_\mathrm{pre}}\right),---\left(22\right)$

2. by three-phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}The voltage error δ u producing_a、δu_bWith δ u_cTake negative respectively Value, obtains and three-phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}Corresponding offset voltage.

As shown in figure 3, the insertion in dead band make inverter 13 export virtual voltage have differences with desired voltage, electric current from Inverter 13 flows to the positive direction that permagnetic synchronous motor 2 is electric current, as a phase current i_aThe error delta producing for timing, phase voltage u_a-For:

${\mathrm{\δu}}_a=\frac{t_d+t_{\mathrm{on}}-t_{\mathrm{off}}}{t_s}{v}_{\mathrm{dc}}---\left(23\right)$

Wherein, t_dFor the Dead Time of setting, t_on、t_offIt is respectively break-over of device time and turn-off time, t_sFor controlling week Phase, v_dcFor DC bus-bar voltage.

In the same manner, electric current i_aDuring for bearing, phase voltage error delta u_a-For:

$\mathrm{\δ}{u}_{a-}=-\frac{t_d+t_{\mathrm{on}}-t_{\mathrm{off}}}{t_s}{v}_{\mathrm{dc}}---\left(24\right)$

Therefore, the phase voltage error that dead band is caused is:

$\mathrm{\δ}{u}_a=\frac{t_d+t_{\mathrm{on}}-t_{\mathrm{off}}}{t_s}{v}_{\mathrm{dc}}\mathrm{sign}\left(i_a\right)---\left(25\right)$

In formula, sign (i_a) it is phase current i_aPolarity, i_a> 0 when, sign (i_a) value be 1, otherwise for -1.

For two electric currents of b, c, obtain corresponding phase voltage error.By coordinate transform, can arrive what dead band caused Dq shaft voltage error, as follows:

$\left[\begin{array}{c}\mathrm{\δ}{u}_d\\ \mathrm{\δ}{u}_q\end{array}\right]=\left[\begin{array}{ccc}\cos \mathrm{\θ}& \cos (\mathrm{\θ}-\frac{2\mathrm{\π}}{3})& \cos (\mathrm{\θ}+\frac{2\mathrm{\π}}{3})\\ -\sin \mathrm{\θ}& -\sin (\mathrm{\θ}-\frac{2\mathrm{\π}}{3})& -\sin (\mathrm{\θ}+\frac{2\mathrm{\π}}{3})\end{array}\right]\·\left[\begin{array}{c}\mathrm{sign}\left(i_a\right)\\ \mathrm{sign}\left(i_b\right)\\ \mathrm{sign}\left(i_c\right)\end{array}\right]\frac{t_d+t_{\mathrm{on}}-t_{\mathrm{off}}}{t_s}{v}_{\mathrm{dc}}---\left(26\right)$

Dead time effect causes to be superimposed a cycle pulsation interference in contravarianter voltage instruction, and then causes inverter defeated Go out the distortion of voltage.Therefore, remedial measure is pulsating volage in contrast in the superposition of inverter link, thus offsetting dead band effect The impact answered.

As shown in figure 4, wherein, busbar voltage v_dc=310v, t_d=125 μ s, t_on=t_off.Can the dq shaft voltage that causes of dead band by mistake Difference presents the pulsation of 6 times of fundamental frequencies, wherein, q shaft voltage error delta u_qLess but exist larger straight for pulsation amplitude The steamed bun ripple of stream biasing, d shaft voltage error delta u_dSawtooth waveforms for amplitude about 10v.

During permagnetic synchronous motor low cruise, when that is, permanent-magnetic synchronous motor rotor rotating speed is less than 300rpm, dead band leads to Dq shaft voltage error delta u_d、δu_qRipple frequency is relatively low, and the simple adjustment effect relying on electric current loop itself is it is possible in certain journey Return in time by adjustment for the current distortion that the dq shaft voltage error that dead band is led to by degree causes.Additionally, during low cruise, phase current exists The near zero-crossing point time is longer, and phase current polarity judges that mistake leads to the possibility by mistake compensating bigger, and compensates possibility by mistake Bring the phenomenons such as zero crossing clamper, cause the distortion that electric current is bigger.Therefore, above-mentioned two aspect factors, motor low speed are considered The impact of the adjustment effect deadband eliminating effect of electric current loop itself during operation, can be relied on, thus not carrying out extra compensation It is feasible.

During permagnetic synchronous motor high-speed cruising, that is, in more than 300rpm, dead band leads to permanent-magnetic synchronous motor rotor rotating speed Dq shaft voltage error delta u_d、δu_qRipple frequency is higher.In general, electric current loop bandwidth is limited, and usually 1khz is left Right.When the operation of power frequency 50hz pressed by one four motor to pole, then phase current fundamental frequency is 200hz, the dq axle electricity that dead band leads to Pressure error delta u_d、δu_qRipple frequency is 1.2khz, basically reaches even more than electric current loop bandwidth.Therefore, under high frequency situations, by Suitable with electric current loop bandwidth in the ripple frequency of error voltage, the simple adjustment effect relying on electric current loop itself has been difficult to eliminate The impact of dead time effect.Additionally, during high-speed cruising, because phase current zero passage required time is shorter, being occurred by noise jamming The possibility by mistake compensating is relatively low.Therefore, contrary with situation during low cruise, during permagnetic synchronous motor high-speed cruising, can To take dead area compensation measure, the voltage of the voltage error contrast causing with dead band in the superposition of inverter link, reach and disappear Except interference obtains the purpose of the more preferable current waveform of sine degree.

As shown in figure 5, output current i_{q_}、i_{d_}Permagnetic synchronous motor 2 rotor exporting with position sensor 1 rotates through Electrical angle θ is separately input to electric current inverse transform block 5, and electric current inverse transform block 5 exports three-phase predicted current i_{a_pre}、i_{b_pre}With i_{c_pre}, according to three-phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}Polarity judge export corresponding offset voltage；Reference voltage Input voltage inverse transform block 11, voltage inverse transform block 11 exports three-phase voltage u_a, u_b, u_c, dead area compensation module 14 exports Offset voltage respectively with three-phase voltage u_a、u_bAnd u_cSuperposition.

As shown in fig. 6, permagnetic synchronous motor first passes through after velocity close-loop control reaches certain rotating speed (230rpm) switching to Current loop control mode, q shaft current instructsIt is set to the AC signal of direct current biasing 1.75a, frequency 100hz, amplitude 0.2a, Current detection value i_qFeed back input as electric current loop adjuster.Electric motor load torque constant for 2n m.Threephase stator electric current i_a、 i_bAnd i_cEach superposition amplitude is about the noise of 0.06a.Inverter adopts perfect switch device, as shown in Figure 6 (a), flat using sliding All wave filters are to current detection value i_qProcessed, sliding window length be set to 8 it can be observed that, current detection value i_qWith filter There is obvious delayed phase or time delay in wave number, its difference is rendered as just (remaining) string waveform it was demonstrated that the presence of time delay.As Fig. 6 Shown in (b), using increment type Kalman filter to current detection value i_qIt is filtered, detected value is presented with the difference of filter value Be the burr near zero, occur significantly fluctuating, increment type kalman filter method do not bring extra time delay or Delayed phase.

As shown in fig. 7, permagnetic synchronous motor first passes through velocity close-loop control and reaching certain rotating speed (about 230rpm) and switches afterwards To current loop control mode, q shaft current instructsIt is set to the exchange letter of direct current biasing 1.75a, frequency 100hz, amplitude 0.2a Number, current detection value i_qFeed back input as electric current loop adjuster.Electric motor load torque constant for 2n m.Threephase stator electricity Stream i_a、i_bAnd i_cEach superposition amplitude is about the noise of 0.06a.Inverter adopts perfect switch device, before the 0.065s moment, Containing noisy current detection value i_qDo not make any feed back input processing directly as current regulator 9；After this moment, inspection Measured value is input to current regulator after the filtering of increment type Kalman filter again.After processing after filtering, such as Fig. 7 (a) Shown, dq shaft current noise amplitude decreases, and as shown in Figure 7 (b) shows, dq shaft voltage noise amplitude is obviously reduced, and the present invention increases Amount formula Kalman filter can effectively reduce system noise.

As shown in figure 8, wherein, inverter 14 adopts perfect switch, phase current i_a、i_bEach superposition amplitude is about making an uproar of 0.06a Sound.Electric motor load torque 1.5n m, rotary speed instruction is set to constant 1000rpm, and in Fig. 8, solid line represents phase current sensing value； Dq shaft current detected value calculates predicted value through the filtering of increment type Kalman filter with incremental forecasting method, then passes through contravariant Get the predicted value of phase current in return, in such as Fig. 8, the predicted value of phase current is represented by dashed line.Due to have passed through filtering and prediction loop Section, the predicted value of phase current smooths than detected value, and this advantageously reduces the current polarity that noise causes and judges that error leads to Compensate by mistake；Meanwhile, in sequential, the predicted value of phase current carries the previous sampling period than detected value, can eliminate a digital control bat stagnant The impact of time delay afterwards, can reduce system noise, reduce the pulsation of dq shaft voltage；Drawn accordingly according to filtered prediction phase current Offset voltage, advantageously reduce the mistake leading to because of phase current polarity erroneous judgement and compensate.

As shown in figure 9, sampling period t_s=125 μ s, voltage dead band set of time is 6 μ s, permagnetic synchronous motor load torque It is set to constant 1.5n m.First stage, using increment type Kalman filter 9 to current detection value i_d、i_qIt is filtered so Input the first electric current loop pi adjuster 10 and the second electric current loop pi adjuster 12 afterwards respectively, the dead-zone compensation method of the present invention acts as With；Second stage, the first electric current loop pi adjuster 10 and the second electric current loop pi adjuster 12 feed back input switch to current detecting Value i_d、i_q, simultaneously dead-zone compensation method of the present invention no longer work.In Fig. 9 (a), permanent-magnetic synchronous motor rotor is at a high speed (1000rpm) when, during using current filtering proposed by the present invention and dead-zone compensation method, phase current i_a、i_bAnd q shaft current i_q、 Q shaft voltage u_qIn waveform, noise content is fewer, and phase current is smoother in zero crossing annex；After stopping adopting the present invention, phase Electric current i_a、i_bAnd q shaft current i_q, q shaft voltage u_qAll containing obvious noise, and phase current i_a、i_bExist in zero crossing annex Significantly distort, current filtering of the present invention and the validity of voltage dead band compensation method are able to demonstrate that by above contrast.

As Fig. 9 (b) -9(c) shown in, during permanent-magnetic synchronous motor rotor low speed.Compared to the high-speed case shown in Fig. 9 a, to the greatest extent Pipe q shaft voltage u_qWaveform still has notable difference before and after institute of the present invention extracting method works, but phase current i_a、i_bAnd q axle Electric current i_qThere is not significant difference in waveform.The voltage cycle that during permanent-magnetic synchronous motor rotor low speed, voltage dead band effect causes Interfering frequency ratio is relatively low, and electric current loop has enough regulating powers to the curent change that it causes, even if in this case not taking Dead area compensation measure, also can obtain the reasonable current waveform of sine degree.

As shown in Figure 10, q shaft current instruction is set to constant 0.5a, makes motor by adjusting dynamometer machine output torque Stabilization of speed is in 1200rpm.When not taking voltage dead band indemnifying measure, as shown in Figure 10 (a) shows, dq shaft current is equal with voltage Occur in that regular dither, wherein pulsation of current amplitude has reached positive and negative 0.1a；And the current filtering of the present invention with After dead-zone compensation method works, such as shown in Figure 10 (b), pulsation of current frequency substantially slows down, and mains ripple amplitude is notable simultaneously Reduce the validity it was demonstrated that current filtering of the present invention and dead-zone compensation method.

As shown in figure 11, the experiment condition of Figure 11 with Figure 10 is identical, contrasts it is obvious that as shown in Figure 11 (a) shows, not Very big distortion is had using the current filtering of the present invention and the phase current waveform of dead-zone compensation method, and adopts the electric current of the present invention After filtering and dead-zone compensation method, shown in such as Figure 11 (b), phase current waveform becomes to smooth very much, distortion significantly reduce it was demonstrated that Effectiveness of the invention.

Shown in Figure 12, the instruction of q shaft current is set to constant 0.5a, makes permanent magnetism same by adjusting dynamometer machine output torque Step motor 2 stabilization of speed is in 500rpm.Contrast Figure 10 and Figure 12, due to the reduction of rotating speed, in Figure 12 (a) and Figure 12 (b), dq Shaft current is reduced with voltage ripple frequency, even if on the premise of not taking dead area compensation measure, pulsation amplitude also has obvious fall Low.With the reduction of frequency, the ability of electric current loop anti-dead time effect impact is strengthened.

As shown in figure 13, the experiment condition of Figure 13 with Figure 12 is identical, because rotating speed is relatively low, even if not taking dead area compensation to arrange Apply, the pulsation amplitude of stator phase currents also has obvious reduction, with the reduction of frequency, the ability of electric current loop anti-dead time effect impact Strengthened.

As shown in figure 14, in Figure 14 (a) and Figure 14 (b), the instruction of q shaft current is set to constant 0.5a, by adjusting Dynamometer machine output torque makes permagnetic synchronous motor 2 rotating speed stablize in 170rpm and 170rpm respectively.With permagnetic synchronous motor The reduction further of rotating speed, even if not taking dead area compensation measure, stator monophase current can obtain the reasonable waveform of sine degree, Because the simple stator relying on the electric current loop adjuster adjustment effect of itself can obtain relatively sine is mutually electric during low speed Stream waveform, then it is inconspicuous to compensate meaning to dead band.Meanwhile, the when anaplasia that during low speed, phase current is detained in zero point annex Long, the judgement to current polarity is affected be more susceptible to noise, and the possibility occurring by mistake compensating is bigger.Therefore, can during low speed Relied on not taking indemnifying measure current regulator itself adjustment effect can deadband eliminating effect impact.

The various embodiments described above are merely to illustrate the present invention, and the structure of wherein each part, connected mode and manufacture craft etc. are all Can be varied from, every equivalents carrying out on the basis of technical solution of the present invention and improvement, all should not exclude Outside protection scope of the present invention.

Claims (4)

1. a kind of permagnetic synchronous motor current filtering and dead area compensation device compensation method it is characterised in that: described compensate dress Put including position sensor, permagnetic synchronous motor, rotating speed computing module, coordinate transformation module, electric current inverse transform block, speed ring Pi adjuster, current sensor, summation module, increment type Kalman filter, the first electric current loop pi adjuster, voltage inverse transformation Module, the second electric current loop pi adjuster, inverter and dead area compensation module；Described coordinate transformation module, increment type Kalman filter Ripple device and the first electric current loop pi adjuster constitute q shaft current ring；Described coordinate transformation module, increment type Kalman filter and Two electric current loop pi adjusters constitute d shaft current ring, and described q shaft current ring and d shaft current ring constitute electric current loop；

The input of described position sensor connects the output end of described permagnetic synchronous motor, the output end of described position sensor Connect described rotating speed computing module, described coordinate die change block and electric current inverse transform block respectively, electrical angle θ collecting is transmitted To described rotating speed computing module, described coordinate die change block and electric current inverse transform block；The rotating speed of described rotating speed computing module output ω as negative-feedback, and with given rotating speed command value ω^*After taking difference, as the input of described speed ring pi adjuster；Described Current sensor connects the stator of described permagnetic synchronous motor, by the three-phase current of the permanent-magnetic synchronous motor stator detecting Biphase current takes through the summation of described summation module after bearing and inputs described coordinate transformation module；Described current sensor is simultaneously also by institute State biphase current and input described coordinate transformation module, described coordinate transformation module carries out described three-phase current after dq coordinate transform Input described increment type Kalman filter, q shaft current detected value i_qWith d shaft current detected value i_dThrough described increment type Kalman After filter process, by q shaft current predictive filtering value i_{q_pre}Input described q shaft current ring and electric current inverse transform block respectively, will Described d shaft current predictive filtering value i_{d_pre}Input described d shaft current ring and electric current inverse transform block respectively；Described q shaft current is pre- Survey filter value i_{q_pre}As q shaft current ring negative-feedback, the output with described speed ring pi adjuster is compared, and fiducial value is input to institute State the first electric current loop pi adjuster and obtain q shaft voltageQ shaft voltageTransmit to described voltage inverse transform block；Described d axle electricity Stream detected value i_{d_pre}As d shaft current ring negative-feedback and previously given electric currentRelatively, fiducial value is input to described second electricity Stream ring pi adjuster obtains d shaft voltageD shaft voltageTransmit to described voltage inverse transform block；Described voltage contravariant die change The output end of block connects the input of described inverter；The output end of described electric current inverse transform block connects described dead area compensation mould The input of block, the output end of described dead area compensation module connects the input of described inverter, the output end of described inverter Connect the input of described permagnetic synchronous motor；

Described compensation method comprises the following steps:

1) current sensor is by the permagnetic synchronous motor detecting threephase stator electric current i_a、i_bAnd i_cInput to coordinate transformation module Interior, the coordinate transform of abc/ α β is carried out to it, obtains the current component i under two-phase rest frame_α、i_β:

$\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_{\mathrm{\β}}\end{array}\right]=\sqrt{\frac{2}{3}}\left[\begin{array}{ccc}1& -\frac{1}{2}& -\frac{1}{2}\\ 0& \frac{\sqrt{3}}{2}& \frac{\sqrt{3}}{2}\end{array}\right]\left[\begin{array}{c}{i}_a\\ i_b\\ i_c\end{array}\right],$

In formula, i_cFor i_a、i_bThe negative value of sum；

2) in coordinate transformation module, electrical angle θ that the permanent-magnetic synchronous motor rotor according to receiving rotates through, static to two-phase Current component i under coordinate system_α、i_βCarry out α β/dq coordinate transform again, obtain the electric current inspection under two-phase synchronous rotary dq coordinate system Measured value i_d、i_q:

$\left[\begin{array}{c}{i}_d\\ i_q\end{array}\right]=\left[\begin{array}{cc}cos\mathrm{\θ}& sin\mathrm{\θ}\\ -sin\mathrm{\θ}& \cos \mathrm{\θ}\end{array}\right]\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_{\mathrm{\β}}\end{array}\right],$

In formula, the electrical angle that θ rotates through for permanent-magnetic synchronous motor rotor, obtained by position sensor；

3) electrical angle θ that permanent-magnetic synchronous motor rotor rotates through inputs to rotating speed computing module, carries out differential to electrical angle θ, Obtain speed feedback value ω；Speed feedback value ω and previously given rotational speed command value ω^*Defeated as speed ring pi adjuster Enter, obtain current instruction value through calculation process

4) current detection value i_q、i_dIt is input in increment type Kalman filter, by increment type Kalman filter output d axle electricity Stream predictive filtering value i_{d_pre}With q shaft current predictive filtering value i_{q_pre}；

5) current instruction valuePreviously given electric currentRespectively with d shaft current predictive filtering value i_{d_pre}Predict filter with q shaft current Wave number i_{q_pre}Relatively, fiducial value is respectively as the input of the first electric current loop pi adjuster, the second electric current loop pi adjuster, Jing Guoyun Calculation processes and respectively obtains the first electric current loop pi adjuster, the reference voltage of the second electric current loop adjuster output

6) d shaft current predictive filtering value i_{d_pre}, q shaft current predictive filtering value i_{q_pre}Permanent magnet synchronous electric with position sensor output Electrical angle θ that machine rotor rotates through is separately input to electric current inverse transform block, by electric current inverse transform block output three-phase prediction electricity Stream i_{a_pre}、i_{b_pre}And i_{c_pre}；

7) three-phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}Input dead area compensation module, dead area compensation module predicts electricity according to three-phase Stream i_{a_pre}、i_{b_pre}And i_{c_pre}Polarity export corresponding offset voltage；Described dead area compensation comprises the following steps:

1. dead area compensation module is according to next cycle three-phase predicted current i receiving_{a_pre}、i_{b_pre}And i_{c_pre}, obtain next week Relevant voltage error delta u that phase three-phase predicted current produces respectively_a、δu_bWith δ u_c:

${\mathrm{\δu}}_a=\frac{t_d+t_{on}-t_{off}}{t_s}{v}_{dc}sign\left(i_{a\_pre}\right),$

${\mathrm{\δu}}_b=\frac{t_d+t_{on}-t_{off}}{t_s}{v}_{dc}sign\left(i_{b\_pre}\right),$

${\mathrm{\δu}}_c=\frac{t_d+t_{on}-t_{off}}{t_s}{v}_{dc}sign\left(i_{c\_pre}\right),$

Sign () be predicted current polarity, predicted current value > 0 when, sign () value be 1, otherwise for -1；t_dDead for setting Area's time, t_on、t_offIt is respectively break-over of device time and turn-off time, t_sFor controlling cycle, v_dcFor DC bus-bar voltage；

2. by three-phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}The voltage error δ u producing_a、δu_bWith δ u_cTake negative value respectively, obtain Arrive and three-phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}Corresponding offset voltage；

8) reference voltageInput voltage inverse transform block, voltage inverse transform block exports three-phase voltage u_a, u_b, u_c, with three Phase predicted current i_{a_pre}、i_{b_pre}And i_{c_pre}Corresponding offset voltage respectively with three-phase voltage u_a, u_b, u_cInversion is inputted after superposition Device, inverter exports corresponding three-phase voltage to permagnetic synchronous motor, drives permagnetic synchronous motor work.

2. as claimed in claim 1 a kind of permagnetic synchronous motor current filtering and dead-zone compensation method it is characterised in that: described Step 4) in, increment type Kalman filter is to current detection value i_d、i_qProcess comprise the following steps:

(1) under synchronous rotating frame, the stator d axle of permagnetic synchronous motor, q shaft voltage equation are:

u_d=ri_d+l_ddi_d/dt-ωl_qi_q,

u_q=ri_q+l_qdi_q/dt+ωl_di_d+ωψ_f,

Wherein u_d、u_qIt is respectively stator d, q shaft voltage, i_d、i_qIt is respectively stator d, q shaft current, r is stator resistance, l_d、l_qRespectively For stator d, q axle inductance, ψ_fFor permanent magnet flux linkage, ω is rotor speed；

(2) according to the stator q shaft voltage equation in step (1), in current period (k) t_sWith a upper cycle (k-1) t_sInside build respectively The discrete voltage equation of vertical permagnetic synchronous motor:

u_q(k)=r_e(i_q(k)+i_{q_pre}(k+1))/2+l_e(i_{q_pre}(k+1)-i_q(k))/t_s+ω(l_di_d+ψ_f),

u_q(k-1)=r (i_q(k)+i_q(k-1))/2+l_q(i_q(k)-i_q(k-1))/t_s+ω(l_di_d+ψ_f),

Wherein i_{q_pre}(k+1) it is the predicted value to next start time in cycle q shaft current, abbreviation current forecasting in current period Value, i_qK () is the current detection value of current period, i_q(k-1) a upper periodic permanent magnet synchronous motor stator q shaft current detected value, t_s For controlling cycle, u_qK () is current period stator q shaft voltage, u_q(k-1) it is a upper cycle stator q shaft voltage, r_e、l_eIt is respectively To permanent-magnetic synchronous motor stator resistance r, stator q axle inductance l_qEstimate；

(3) ignore the change of the voltage term related to rotating speed, two formula in step (2) are subtracted each other, obtains permanent magnet synchronous electric The simplification current increment formula of machine, because r_eMuch smaller than l_e/t_s, therefore ignore the impact of r, obtain in current period to next week Predicted value i of start time phase d shaft current_{d_pre}(k+1), and by current increment formula change into matrix form:

$x_k=\left[\begin{array}{c}{i}_q\left(k\right)\\ i_q(k-1)\end{array}\right],$

$x_{k-1}=\left[\begin{array}{c}{i}_q(k-1)\\ i_q(k-2)\end{array}\right],$

$f_{k-1}=\left[\begin{array}{cc}2& -1\\ 1& 0\end{array}\right],$

$b_{k-1}=\left[\begin{array}{c}{t}_s/l_q\\ 0\end{array}\right],$

$c={\left[\begin{array}{c}1\\ 0\end{array}\right]}^t;$

(4) according to the Mathematical Modeling that the current increment formula of step (3) matrix form sets up increment type Kalman filter it is:

$\left\{\begin{array}{c}{x}_k=f_{k-1}{x}_{k-1}+b_{k-1}{u}_{k-1}+w\\ y_k={\mathrm{cx}}_k+v\end{array}\right.,$

Wherein, w is input noise vector, and v is output noise vector；x_k、x_k-1For system mode vector, y_kFor system export to Amount, u_k-1For dominant vector；f_k-1、b_k-1, c be coefficient matrix；

(5) Mathematical Modeling according to increment type Kalman filter, is iterated to its correlated variables, obtains optimal estimation value

3. as claimed in claim 2 a kind of permagnetic synchronous motor current filtering and dead-zone compensation method it is characterised in that: described In step (5), described optimal estimation valueComputational methods comprise the following steps:

1. calculate prior estimate vector valueWith corresponding error matrix

${\hat{x}}_k^{-}=f_{k-1}{\hat{x}}_{k-1}+b_{k-1}{u}_{k-1},$

$p_k^{-}=f_{k-1}{p}_{k-1}{f}_{k-1}^t+q_{k-1},$

Wherein, q_k-1For noise matrix q_k-1,Optimal estimation vector value for system state variablesIn (k-1) cycle State vector,For kth cycle prior estimate vector, it is an intermediate variable,For kth cycle prior estimate error matrix, For intermediate variable matrix, p_k-1For system (k-1) cycle error matrix；

2. calculate gain matrix k_k:

$k_k=p_k^{-}{c}^t{({\mathrm{cp}}_k^{-}{c}^t+r_{k-1})}^{-1};$

3. computing system is in the optimal estimation value of kth periodic system state variable

${\hat{x}}_k={\hat{x}}_k^{-}+k_k(y_k-c{\hat{x}}_k^{-}),$

Whereini_{q_}(k-1) it is permanent-magnetic synchronous motor rotor (k-1) current detection value i_qOptimal estimation Value, i_{q_}K () is permanent-magnetic synchronous motor rotor in kth periodic current detected value i_qOptimal estimation value；

4. calculate the error matrix p in kth cycle_kOptimal estimation value:

$p_k=p_k^{-}-k_k{\mathrm{cp}}_k^{-},$

Wherein, q_k-1、r_k-1It is respectively the covariance matrix of noise w, v, error matrix p_kFor the optimal estimation value in estimation process Error matrix, by successive ignition, error matrix p_kEventually converge to null matrix.

4. as claimed in claim 1 a kind of permagnetic synchronous motor current filtering and dead-zone compensation method it is characterised in that: described Step 6) in, in described electric current inverse transform block, processing procedure comprises the following steps:

1. predict next periodic permanent magnet synchronous electric motor rotor coordinate transform angle, θ_pre, due to permagnetic synchronous motor mechanical time Constant is much larger than the state of electrical time constant operation then it is assumed that motor remains a constant speed at short notice, i.e. permagnetic synchronous motor The angle, θ that rotor turned within next cycle with current period is consistent；

2. combine the predictive filtering value of dq shaft current, by coordinate transform, obtain the predicted value of the three-phase current in next cycle i_{a_pre}、i_{b_pre}And i_{c_pre}For:

$\left[\begin{array}{c}{i}_{a\_pre}\\ i_{b\_pre}\\ i_{c\_pre}\end{array}\right]=\left[\begin{array}{cc}{\mathrm{cos\θ}}_{pre}& -{\mathrm{sin\θ}}_{pre}\\ \cos ({\mathrm{\θ}}_{pre}-\frac{2\mathrm{\π}}{3})& -\sin ({\mathrm{\θ}}_{pre}-\frac{2\mathrm{\π}}{3})\\ \cos ({\mathrm{\θ}}_{pre}+\frac{2\mathrm{\π}}{3})& -\sin ({\mathrm{\θ}}_{pre}+\frac{2\mathrm{\π}}{3})\end{array}\right]\left[\begin{array}{c}{i}_{d\_pre}\\ i_{q\_pre}\end{array}\right],$

And predicted value i of next cycle three-phase current is calculated according to above formula_{a_pre}、i_{b_pre}And i_{c_pre}.