CN104362923B - Decoupling SVPWM (space vector pulse width modulation) based fault tolerance control method for open-winding PMSM (permanent magnet synchronous motor) driving system - Google Patents

Abstract

The invention provides a decoupling SVPWM (space vector pulse width modulation) based fault tolerance control method for an open-winding PMSM (permanent magnet synchronous motor) driving system. The method includes when a bridge arm of double inverters has an open-circuit fault, switching on a bidirectional thyristor between a motor phase endpoint, connected with the faulted bridge arm, and a direct-current-side filter capacitor midpoint to realize reconstruction of a topological structure; performing fault tolerance control on the reconstructed topological structure on the basis of decoupling SVPWM, performing SVPWM control on the inverter on the faulted side on the basis of a 90-degree coordinate system, and performing SVPWM control on the inverter on the normal side on the basis of a three-phase coordinate system with a, b and c phases. Compared with the prior art, the decoupling SVPWM based fault tolerance control method has the advantages that procedures after fault tolerance are simplified greatly, reference voltage vectors are proportionally distributed according to effective sectors of maximum output voltages of the inverters on the normal side and on the faulted side, and the utilization ratio of direct-current-side voltages of the inverters is maximized.

Description

A kind of based on decoupling svpwm open winding pmsm drive system fault tolerant control method

Technical field

The present invention relates to a kind of three-phase opens the faults-tolerant control after winding pmsm twin inverter drive system list brachium pontis open circuit, belong to Control field in permagnetic synchronous motor.

Background technology

In recent years, twin inverter topological structure Successful utilization is in the high-power driving system such as space flight, electric automobile, for Drive system, the switching tube fault in inverter occupies significant portion in institute is faulty, therefore twin inverter topological structure Reliability and stability concern the reliable and stable of whole drive system, thus the necessary appearance to twin inverter topological structure Wrong control is studied.

There is document that the pmsm drive system faults-tolerant control based on twin inverter topological structure is studied, these Document is mainly for the fault-tolerance study of single tube open fault, single brachium pontis open fault, open-phase fault etc..When Single switch pipe fault Afterwards, by control realization itself Real-time Reconstruction of switch tube drive signal, and then on this basis control algolithm is changed Become, reach fault-tolerant purpose, but half when now the maximum active voltage vector of twin inverter is normal, and this can make pmsm Under rated current service condition, maximal rate does not reach normal speed it has to pass through to improve twin inverter DC voltage Grade is compensating the magnitude of voltage reducing because of reconstruct.For single brachium pontis open fault, by changing the power supply of twin inverter Mode, is switched over to single supply power supply mode by dual power supply mode, realizes the biphase fault-tolerant operation of motor, but this It is nominal torque that sample can make output torque under rated current operation for the pmsmTimes, so can reduce the band of pmsm Loading capability, reduces electric efficiency.

Three-phase under accidental conditions open winding pmsm drive system be based on overall svpwm control, by based on a, The svpwm control of b, c tri- phase coordinate system enormously simplify overall control program.Then 90 degree are based on for the svpwm after fault-tolerant Coordinate system, zonal control, modulator approach and traditional svpwm control on the whole reaches unanimity, but due to opening up after failure reconfiguration Flutter the particularity of structure, whole fault-tolerant control system program is complicated.

Winding pmsm drive system is opened for three-phase, after single brachium pontis open fault occurs, the output torque of pmsm need to be kept Ability, the rotating speed fan-out capability after maximization raising is fault-tolerant, the svpwm based on a, b, c tri- phase coordinate system under accidental conditions Control the control being not applied for fault side inverter.Because the effective vector of the voltage of latter two inverter of failure reconfiguration exports energy Power is not reciprocity, and therefore maximally utilizing twin inverter DC voltage becomes the emphasis of fault-tolerant operation.

Content of the invention

Goal of the invention: for the problems referred to above, the present invention seeks to proposition is a kind of being driven based on the winding pmsm that opens of decoupling svpwm Dynamic System Fault Tolerance control method is so that twin inverter drive system output voltage capability after fault-tolerant is big, the letter of faults-tolerant control program Change, also will take into account twin inverter drive system simultaneously and maximally utilize.

Technical scheme: for achieving the above object, the present invention adopts the following technical scheme that

A kind of based on decoupling svpwm open winding pmsm drive system fault tolerant control method, comprising:

After there is open fault in a certain brachium pontis of twin inverter, motor phase end points and DC side that conducting failure brachium pontis connects Bidirectional thyristor between filter capacitor midpoint, realizes the reconstruct of topological structure；

Decoupling svpwm is based on to the topological structure after reconstruct and carries out faults-tolerant control, fault side inverter is based on 90 degree of seats Mark system carries out svpwm control, carries out svpwm control to normal side inverter based on a, b, c tri- phase coordinate system.

Described topological structure after reconstruct is included based on the decoupling concrete steps that are controlled of svpwm:

(1) three-phase current that pmsm exports is carried out clark and park coordinate transform, so that three-phase static coordinate system is converted into Two-phase rotating coordinate system, obtains electric current id and iq；

(2) given rotating speed is adjusted through der Geschwindigkeitkreis pi with motor speed feedback and obtains q axle reference current；

(3) q axle reference current and iq feedback adjusts through q shaft current ring pi and obtains q axle reference voltage, 0 reference current with Id feed back into d shaft current ring pi adjust obtain d axle reference voltage, d shaft voltage and q shaft voltage are obtained through park inverse transformation Reference voltage v_ref；

(4) by v_refVoltage output ability ratio according to two inverters is allocated, and obtains fault side inverter reference voltage v_ref1With normal side inverter reference voltage v_ref2；

(5) according to v_ref1Based on 90 degree of coordinate systems, svpwm control is carried out to fault side inverter and obtains non-faulty inverter Switching signal, according to v_ref2Based on a, b, c tri- phase coordinate system, svpwm control is carried out to normal side inverter and obtains healthy inverter Switching signal.

Beneficial effect: compared with prior art, the present invention has the advantage that 1) when brachium pontis generation a certain in twin inverter After open fault, by corresponding Continuity signal is applied to two-way controlled thyristor accordingly, it is capable of single brachium pontis open circuit event Barrier topology reconstruction.2) 0.75 times when the effective vector of the maximum output voltage of the drive system after failure reconfiguration is normal.3) event Fault-tolerant control algorithm after barrier judges without sector, simple.4) the faults-tolerant control program after fault can realize double inversions Device DC voltage utilization rate maximizes.

Brief description

Fig. 1 be the dual power supply in the inventive method open winding three-phase pmsm driving system structure figure；

Fig. 2 be dual power supply open winding three-phase pmsm drive system voltage vector-diagram；

Fig. 3 be dual power supply open winding three-phase pmsm drive system single armed failure reconfiguration figure；

Fig. 4 is the output voltage vector figure after winding three-phase pmsm drive system single armed failure reconfiguration of opening of dual power supply:

(a) fault side inverter voltage vector-diagram, (b) normal side contravarianter voltage vectogram；

Fig. 5 be based on decoupling svpwm open winding pmsm drive system faults-tolerant control structure chart；

Fig. 6 is the structural representation of decoupling svpwm.

Specific embodiment

With reference to specific embodiment, it is further elucidated with the present invention it should be understood that these embodiments are merely to illustrate the present invention Rather than restriction the scope of the present invention, after having read the present invention, the various equivalences to the present invention for the those skilled in the art The modification of form all falls within the application claims limited range.

For ease of understanding technical scheme, introduce three-phase first and open winding pmsm twin inverter drive system The normal active voltage vector running output.Fig. 1 be dual power supply open winding three-phase pmsm driving system structure figure, double inverse Supply voltage dc1, dc2 of becoming device are into e.

There are two kinds of on off states, when upper brachium pontis switching tube turns on, on off state in every phase brachium pontis of twin inverter system It is designated as " 1 "；During brachium pontis switching tube conducting instantly, on off state is designated as " 0 ", thus, the on off state s of twin inverter system_kCan It is expressed as:

(formula 1)

Wherein, k is a₁、b₁、c₁、a₂、b₂、c₂.

The voltage vector v that twin inverter system produces_rTwo two-level inverter independent role gained voltages can be regarded as The superposition of space vector, that is, meet v_r=v_s1-v_s2, wherein v_s1、v_s2For the corresponding space vector of voltage of each inverter.Often Individual inverter has eight kinds of spatialities, is followed successively by 1,2,3,4,5,6,7,8, corresponding switch combination be [100], [110], [010], [011], [001], [101], [000] and [111].Output effective maximum voltage vector of each inverter is 2e/3, Output effective maximum voltage vector of twin inverter is 4e/3, as shown in Figure 2.

Disclosed in the embodiment of the present invention a kind of based on decoupling svpwm open winding pmsm drive system fault tolerant control method, Including the topological structure reconstruct after twin inverter one brachium pontis open fault, and faults-tolerant control is carried out based on decoupling svpwm.

As shown in figure 1, the present invention based on pmsm drive system relatively open winding drive system with traditional dual power supply, increase Add 6 bidirectional thyristors, be located at respectively between inverter every phase brachium pontis midpoint and the power supply midpoint of corresponding inverter, when After the switching tube generation open fault of arbitrary brachium pontis is detected, allow corresponding two-way controlled thyristor to turn on, realize the weight of topology Structure.Taking a phase brachium pontis of inverter 1 as a example, three-phase open winding pmsm twin inverter drive system list brachium pontis open circuit after reconstruct image such as Shown in Fig. 3, for inverter 1, the midpoint of the fault brachium pontis voltage with respect to 1 point is the half of DC voltage, now synthesizes Space vector of voltage as shown in figure 4, corresponding voltage vector is respectively v_1-1、v_1-2、v_1-3、v_1-4, amplitude respectively e/3,e/3、The active voltage vector v of normal side inverter output_2-1、v_2-2、v_2-3、v_2-4、v_2-5、v_2-6, amplitude For 2e/3.The radius of active voltage vector circle of fault side inverter output and normal side inverter output as can be seen from Figure 4 Active voltage vector garden radius value than for 0.5, be designated as p.

Fig. 5-6 is to open winding pmsm drive system faults-tolerant control structural representation based on decoupling svpwm, and the present invention applies Mainly comprised the steps that based on the winding pmsm drive system fault tolerant control method of opening of decoupling svpwm in this control structure

Step (1): three traditional phase coordinate systems are carried out clark coordinate transform, makes three-phase static coordinate system be converted into two Cordic phase rotator system.

Step (2): given rotating speed forms speed closed loop with motor speed feedback.

Step (3): electric current loop adopts id=0 control mode, der Geschwindigkeitkreis are electric with the iq after coordinate transform after pi regulation Stream forms current closed-loop, and given id forms current closed-loop with the id electric current after coordinate transform, and both form d axle after pi regulation Voltage ud and q shaft voltage uq.According to d shaft voltage ud and q shaft voltage uq, form reference voltage v through park inverse transformation_ref.

Step (4): by v_refVoltage output ability ratio according to two inverters is allocated, and obtains fault side inverter ginseng Examine voltage v_ref1With normal side inverter reference voltage v_ref2.

Specifically, the present invention pass through decoupling svpwm faults-tolerant control it may be assumed that

v_ref=v_ref1—v_ref2(formula 2)

Wherein v_refThe reference voltage of input, v_ref1、v_ref2It is respectively the reference of fault side inverter and normal side inverter Voltage vector.

We understand v_refMould must be less than or equal to v_ref1、v_ref2Modulus value sum, therefore to allow two inverters output bigger Active voltage vector circle, we can be v_refIt is decomposed into the voltage vector of two angle mutual deviation 180 degrees, realize uneoupled control. Additionally, the voltage vector-diagram with reference to two inverters in Fig. 4 we can see that only v_1-1、v_2-1, v_1-3、v_2-4These two pair electricity The angle of pressure vector is equal, therefore must be less than by the global voltage vector radius of graph that the voltage vector of two inverter outputs forms The voltage vector radius of circle sum of two inverter outputs.Therefore according to uneoupled control, the voltage vector that two inverters obtain The radius value of circle is more than value during overall vector controlled.

Therefore v_refVoltage output ability ratio according to two inverters is allocated, fault side inverter and normal side inverter Output reference voltage than for p, i.e. v_ref1For v_ref/ 3, v_ref2For -2v_ref/3.

Step (5): according to v_ref1Based on 90 degree of coordinate systems, svpwm control is carried out to fault side inverter and obtains fault inversion The switching signal of device, according to v_ref2To normal side inverter based on a, b, c tri- phase coordinate system carry out svpwm control obtain normally inverse Become the switching signal of device.

Drive system twin inverter fault side inverter after reconstruct is using the svpwm vector controlled based on 90 degree of coordinate systems Modulation strategy is as follows:

As shown in Figure 4, the output voltage vector figure of fault side inverter is divided into 4 intervals, is designated as 1-1,1-2,1-3,1- 4,90 degree of adjacent sectors mutual deviation.

1. fault side synthesized voltage vector is calculated action time

Work as v_ref1When falling into 1-1 interval, by v_1-1、v_1-2Synthesis, is respectively t action time_1-1、t_1-2, t_sFor switching tube conducting Cycle.According to volt-second characteristic, can draw:

v_1-1×t_1-1+v_1-2×t_1-2=v_ref1×t_s(formula 3)

v_ref1=v_α1+jv_β1(formula 4)

Wherein v_α1With v_β1For v_ref1Projection components under α, β coordinate system.

Make m=3v_α1×t_s/ e, $n=\sqrt{3}{v}_{\mathrm{\β}1}\×t_s/e$

Can obtain the ON time of the every phase of inverter:

$\left\{\begin{array}{c}\mathrm{tsb}1=0.5\×(t_s+n-m)\\ \mathrm{tsc}1=0.5\×(t_s-n-m)\end{array}\right.$ (formula 5)

Wherein tsb1, tsc1 are the biphase ON time of switching tube b, c.

According to the computational methods of 1-1 sector, but the ON time of its excess-three sector two switching tube same.By calculating, The ON time of the switching tube of four sectors is all formula 5.

2. fault side synthesized voltage vector open sequence

In order to reduce the open and close times of switching tube, the change of each on off sequence only changes conducting and the pass of a switching tube Disconnected.Because switch combination now does not have zero vector, therefore pass through v_1-2, v_1-4Action time equal, synthesize zero vector.Therefore s_b1s_c1Open mode be five segment encodes, that is, open sequence be 00-10-11-10-00.

The inverter of the drive system twin inverter normal side after reconstruct is using the svpwm based on a, b, c tri- phase coordinate system Vector controlled modulation strategy is as follows:

As shown in Figure 4, the output voltage vector figure of this inverter is divided into 6 intervals, is designated as 2-1,2-2,2-3,2-4,2- 5th, 2-6,60 degree of adjacent sectors mutual deviation.

1. normal side synthesized voltage vector is calculated action time

Work as v_ref2When falling into 2-1 interval, by v_2-1、v_2-2Synthesis, according to volt-second characteristic, can draw:

v_ref2×t_s=v_2-1×t_2-1+v_2-2×t_2-2(formula 6)

According to formula 5, the projection expansih under α, β coordinate system can be obtained and can obtain v₂-₁、v₂-₂T action time_2-1、t_2-2:

$\left\{\begin{array}{c}{t}_{2-1}=(\frac{3}{2}{v}_{\mathrm{\α}2}-\frac{\sqrt{3}}{2}{v}_{\mathrm{\β}2})\×t_s/e\\ t_{2-2}=\frac{\sqrt{3}}{2}{v}_{\mathrm{\β}2}\×t_s/e\end{array}\right.$ (formula 7)

Wherein v_α2With v_β2For v_ref2Projection components under α, β coordinate system.

According to coordinate transform:

$\left[\begin{array}{c}{v}_a\\ v_b\\ v_c\end{array}\right]=\sqrt{2/3}\left[\begin{array}{ccc}1& 0& 1/\sqrt{2}\\ -0.5& \sqrt{3}/2& 1/\sqrt{2}\\ -0.5& -\sqrt{3}/2& 1/\sqrt{2}\end{array}\right]\left[\begin{array}{c}{v}_{\mathrm{\α}2}\\ v_{\mathrm{\β}2}\end{array}\right]$ (formula 8)

Can obtain:

$\left\{\begin{array}{c}{t}_{2-1}=(v_a-v_b)\×t_s/e\\ t_{2-2}=(v_b-v_c)t_s/e\end{array}\right.$ (formula 9)

$\left\{\begin{array}{c}a=v_a\×t_s/e\\ b=v_b\×t_s/e\\ c=v_c\×t_s/e\end{array}\right.$ (formula 10)

Can obtain the ON time of the every phase of inverter:

$\left\{\begin{array}{c}\mathrm{tsa}2=a+\frac{t_s}{2}-\frac{1}{2}(a+c)\\ \mathrm{tsb}2=b+\frac{t_s}{2}-\frac{1}{2}(a+c)\\ \mathrm{tsc}2=c+\frac{t_s}{2}-\frac{1}{2}(a+c)\end{array}\right.$ (formula 11)

Wherein tsa2, tsb2, tsc2 are the ON time of switching tube a, b, c three-phase.

If the maximum in a, b, c is x, minima is y

In the first sector, the maximum of a, b, c is a, and minima is c, so substitute into formula 10 can obtain

$\left\{\begin{array}{c}\mathrm{tsa}2=a+\frac{t_s}{2}-\frac{1}{2}(x+y)\\ \mathrm{tsb}2=b+\frac{t_s}{2}-\frac{1}{2}(x+y)\\ \mathrm{tsc}2=c+\frac{t_s}{2}-\frac{1}{2}(x+y)\end{array}\right.$ (formula 12)

Calculate the ON time of remaining each switching tube in 5 sectors in the same way, and respectively mutually switch in each interval Pipe ON time is described in formula 11.

2. normal side synthesized voltage vector open sequence

In order to reduce the open and close times of switching tube, the change of each on off sequence only changes conducting and the pass of a switching tube Disconnected.s_a2s_b2s_c2Open mode be five segment encodes, that is, open sequence be 000-100-110-111-110-100-000.

Claims (4)

1. a kind of based on decoupling svpwm open winding pmsm drive system fault tolerant control method it is characterised in that include:

After a certain brachium pontis of twin inverter occurs open fault, motor phase end points and DC side that conducting failure brachium pontis connects filter Bidirectional thyristor between electric capacity midpoint, realizes the reconstruct of topological structure；

Decoupling svpwm is based on to the topological structure after reconstruct and carries out faults-tolerant control, 90 degree of coordinate systems are based on to fault side inverter Carry out svpwm control, based on a, b, c tri- phase coordinate system, svpwm control is carried out to normal side inverter；

Described topological structure after reconstruct is included based on the decoupling concrete steps that are controlled of svpwm:

(1) three-phase current that pmsm exports is carried out clark and park coordinate transform, so that three-phase static coordinate system is converted into biphase Rotating coordinate system, obtains electric current id and iq；

(2) given rotating speed is adjusted through der Geschwindigkeitkreis pi with motor speed feedback and obtains q axle reference current；

(3) q axle reference current is adjusted through q shaft current ring pi with iq feedback and obtains q axle reference voltage, and 0 reference current is anti-with id Feed is crossed d shaft current ring pi and is adjusted and obtains d axle reference voltage, and d shaft voltage and q shaft voltage are obtained reference through park inverse transformation Voltage v_ref；

(4) by v_refVoltage output ability ratio according to two inverters is allocated, and obtains fault side inverter reference voltage v_ref1 For v_ref/ 3 and normal side inverter reference voltage v_ref2For -2v_ref/3；

(5) according to v_ref1Based on 90 degree of coordinate systems, svpwm is carried out to fault side inverter and controls the switch letter obtaining non-faulty inverter Number, according to v_ref2Based on a, b, c tri- phase coordinate system, svpwm is carried out to normal side inverter and controls the switch obtaining healthy inverter Signal；

Carried out when svpwm controls to fault side synthesized voltage vector action time based on 90 degree of coordinate systems in described step (5) Computing formula is:

$\left\{\begin{array}{c}tsb1=0.5\×(t_s+n-m)\\ tsc1=0.5\×(t_s-n-m)\end{array}\right.$

Wherein, if a phase open circuit, tsb1, tsc1 are the biphase ON time of switching tube b, c, m=3v_α1×t_s/ e,t_sFor switching tube turn-on cycle, v_α1With v_β1For v_ref1Projection components under α, β coordinate system, e is inversion The supply voltage of device.

2. according to claim 1 based on decoupling svpwm open winding pmsm drive system fault tolerant control method, its feature It is, in described step (5), carry out the s of fault side synthesized voltage vector when svpwm controls based on 90 degree of coordinate systems_b1s_c1Open Logical mode is five segment encodes, that is, opening sequence is 00-10-11-10-00, and 1 represents brachium pontis conducting in every phase, and 0 represents brachium pontis under every phase Conducting.

3. according to claim 1 based on decoupling svpwm open winding pmsm drive system fault tolerant control method, its feature It is, carry out when svpwm controls, normal side synthesized voltage vector being acted on based on a, b, c tri- phase coordinate system in described step (5) The computing formula of time is:

$\left\{\begin{array}{c}tsa2=a+\frac{t_s}{2}-\frac{1}{2}(x+y)\\ tsb2=b+\frac{t_s}{2}-\frac{1}{2}(x+y)\\ tsc2=c+\frac{t_s}{2}-\frac{1}{2}(x+y)\end{array}\right.$

Wherein,

$\left[\begin{array}{c}{v}_a\\ v_b\\ v_c\end{array}\right]=\sqrt{2/3}\left[\begin{array}{ccc}1& 0& 1/\sqrt{2}\\ -0.5& \sqrt{3}/2& 1/\sqrt{2}\\ -0.5& -\sqrt{3}/2& 1/\sqrt{2}\end{array}\right]\left[\begin{array}{c}{v}_{\mathrm{\α}2}\\ v_{\mathrm{\β}2}\end{array}\right]$

Wherein tsa2, tsb2, tsc2 are the biphase ON time of switching tube a, b, c, and x is the maximum in a, b, c, and y is a, b, c In minima, t_sFor switching tube turn-on cycle, v_α2With v_β2For v_ref2Projection components under α, β coordinate system, e is inverter Supply voltage.

4. according to claim 1 based on decoupling svpwm open winding pmsm drive system fault tolerant control method, its feature It is, in described step (5), normal side synthesized voltage vector when svpwm controls is carried out based on a, b, c tri- phase coordinate system s_a2s_b2s_c2Open mode be seven segment code, that is, open sequence be 000-100-110-111-110-100-000,1 represent every phase on Brachium pontis turns on, and 0 represents brachium pontis conducting under every phase.