阅读说明：本技术 一种基于新型容错开关表的五相永磁同步电机容错直接转矩控制方法 (A kind of fault-tolerant Direct Torque Control of five-phase PMSM based on New Fault-tolerant switch list ) 是由 刘国海 曹彦琳 周华伟 高猛虎 于 2019-07-24 设计创作，主要内容包括：本发明公开了一种基于新型容错开关表的五相永磁同步电机容错直接转矩控制方法,首先建立故障状态下的电机数学模型,通过修正的磁链方程和转矩方程计算电机的定子磁链ψ<Sub>s</Sub>和转矩T<Sub>e</Sub>的估测值,将其与给定的定子磁链ψ<Sub>s</Sub><Sup>*</Sup>和转矩T<Sub>e</Sub><Sup>*</Sup>作差,结合定子磁链矢量所在扇区,根据控制要求选取容错开关表内相应的空间电压矢量实现对电机转矩和定子磁链的直接控制。再将容错开关表应用于无故障情况下的五相永磁同步电机,得到与无故障电机使用传统开关表时相同的动态和稳态性能。本发明保证电机在使用同一开关表的条件下,单相开路故障前后电机输出转矩和动态性能保持一致,且能有效抑制电机转矩脉动,大大简化了开关表的设计。(The invention discloses a kind of fault-tolerant Direct Torque Controls of the five-phase PMSM based on New Fault-tolerant switch list, initially set up the motor mathematical model under malfunction, and the stator magnetic linkage ψ of motor is calculated by modified flux linkage equations and torque equation s With torque T e Estimated value, by itself and given stator magnetic linkage ψ s * With torque T e * It is poor to make, the sector in conjunction with where stator magnetic linkage vector, requires to choose corresponding space voltage vector realization in fault-tolerant switch list according to control and directly controls to motor torque and stator magnetic linkage.Fault-tolerant switch list is applied to the five-phase PMSM under non-failure conditions again, identical dynamic and steady-state performance when obtaining with fault-free motor using traditional switch table.The present invention guarantees motor under conditions of using same switch list, and motor output torque and dynamic property are consistent before and after single-phase open-circuit fault, and can effectively inhibit motor torque ripple, enormously simplifies the design of switch list.)

1. a kind of fault-tolerant Direct Torque Control of five-phase PMSM based on New Fault-tolerant switch list, feature exist In, comprising the following steps:

Step 1, the mathematical model under the single-phase open circuit of five-phase PMSM is established, flux linkage equations and the torque side of motor are obtained Journey；

Step 2, by revised flux linkage equations and torque equation, stator magnetic linkage ψ is calculated_sWith torque T_eReal-time estimation value, will Given torque T_e ^*With estimation torque T_eΔ T is obtained as difference_e, by given magnetic linkage ψ_s ^*With estimation magnetic linkage ψ_sΔ ψ is obtained as difference_s, by stagnant Ring controller obtains respective symbol function；

Step 3, by α β plane and z₁z₂Plane is divided into ten sectors, is boundary with the center line of two neighboring big vector Line, 36 ° divide a sector into, and carry out label, stator magnetic linkage vector ψ to sector_sIn α β plane, triple harmonic current error delta i_z In z₁z₂Plane, each sector correspond to corresponding space voltage vector；

Step 4, according to torque transient deviation Δ T_eWith stator magnetic linkage transient deviation Δ ψ_s, in conjunction with triple harmonic current error delta i_z Control sector where with stator magnetic linkage vector, choose corresponding space voltage vector in fault-tolerant switch list realize to motor torque with Stator magnetic linkage directly controls；

Step 5, fault-tolerant switch list is applied in normal five-phase PMSM system, is realized to torque and stator magnetic linkage Directly control.

2. the fault-tolerant Direct Torque of a kind of five-phase PMSM based on New Fault-tolerant switch list according to claim 1 Control method, which is characterized in that in the step 1, mathematical model is as follows when five-phase PMSM A phase open-circuit fault:

Flux linkage equations:

Torque equation:

In formula: i_α、i_β、ψ_α、ψ_βThe respectively component of electric current and stator magnetic linkage in α β plane, L_smFor magnetizing inductance, ψ_fFor permanent magnetism Body magnetic linkage amplitude, θ are rotor position angle, and p is number of pole-pairs.

3. the fault-tolerant Direct Torque of a kind of five-phase PMSM based on New Fault-tolerant switch list according to claim 2 Control method, which is characterized in that in the step 2, revised flux linkage equations are as follows:

Revised torque equation:

By stator magnetic linkage under open-circuit fault α axis component amplitude increase to motor operate normally when ψ_αAmplitude is identical, β axis stator Magnetic linkage remains unchanged, then the electric current before and after failure on α β coordinate system is identical, and torque equation is constant, i.e., stator magnetomotive force track is not Become, so as to realize the unperturbed fault-tolerant operation of motor.

4. the fault-tolerant Direct Torque of a kind of five-phase PMSM based on New Fault-tolerant switch list according to claim 1 Control method, which is characterized in that in the step 3, ignore the leakage inductance of motor, the expression formula of triple harmonic current error are as follows:

In formula: u_z、i_zRespectively third harmonic voltage vector and current phasor, u^* _z、i^* _zRespectively given third harmonic voltage arrow Amount and its corresponding current phasor, Δ i_z=i^* _z-i_zFor triple harmonic current error vector；R_sFor phase winding resistance；

Five-phase PMSM is under single-phase open-circuit fault, the corresponding space electricity in each sector in the one-dimensional space and three-dimensional space Pressure vector may be expressed as:

In formula: V_s ¹、V_s ³Respectively indicate the space voltage vector in the one-dimensional space and three-dimensional space；U_dcIt is expressed as contravarianter voltage The voltage in source；S_i(i=B, C, D, E) respectively indicates the switch state of the every phase bridge arm of inverter, S_iWhen=1, corresponding bridge arm is indicated Upper tube is open-minded, down tube shutdown, S_iWhen=0, indicate that the down tube of corresponding bridge arm is open-minded, upper tube shutdown.

5. the fault-tolerant Direct Torque of a kind of five-phase PMSM based on New Fault-tolerant switch list according to claim 1 Control method, which is characterized in that in the step 3, when motor A phase is opened a way, in order to realize virtual stator magnetic linkage, electromagnetism simultaneously The specific choice method of torque and triple harmonic current control errors, space voltage vector is as follows:

1) according to z₁z₂Triple harmonic current error vector Δ i in plane_zLocating sector determines that can be allowed to a reduced sky Between voltage vector；

2) judge virtual stator magnetic linkage vector ψ_sLocating sector, and acted on according to each voltage vector in this analysis 1), that is, cause virtual Stator magnetic linkage amplitude and the effect of electromagnetic torque variation, select relevant voltage vector；

3) according to analysis 2) as a result, list obtains the switching vector selector table for inhibiting triple-frequency harmonics, according to the virtual stator of table realization Magnetic linkage amplitude and electromagnetic torque track its given value, while by triple harmonic current error vector Δ i_zControl is zero；

As triple harmonic current error vector Δ i_zWhen positioned at sector 1., Δ i can be made_zReduced voltage vector has: space voltage arrow Measure V13, space voltage vector V1, space voltage vector V9, space voltage vector V15, space voltage vector V11, space voltage Vector V8, if stator magnetic linkage vector ψ at this time_sPositioned at sector 1. in, while increase magnetic linkage amplitude, then Δ ψ_s=1, electromagnetism turns Square improves, then Δ T_e=1, meeting conditions above voltage vector has: space voltage vector V8, space voltage vector V13；Due to In α β plane, space voltage vector V8 is better than space voltage vector V13 to the control effect of torque and magnetic linkage, therefore selects empty Between voltage vector be V8；If stator magnetic linkage vector ψ at this time_sPositioned at sector 10. in, while reduce magnetic linkage amplitude, then Δ ψ_s=- 1, electromagnetic torque reduces, then Δ T_e=-1 can make Δ i_zReduced voltage vector only has V15, works as ψ_sWith this when positioned at other sectors Analogize.

6. the fault-tolerant Direct Torque of a kind of five-phase PMSM based on New Fault-tolerant switch list according to claim 1 Control method, which is characterized in that in the step 5, fault-tolerant switch list is realized under five-phase PMSM A phase open-circuit fault To after the directly controlling of motor torque and stator magnetic linkage, which can be used to control five-phase PMSM fault-free fortune Row inhibits triple harmonic current；

When motor A phase is opened a way, S is used_B—S_ETetrad is numbered as voltage vector；When motor operates normally, make Use S_A—S_EFive bits as voltage vector number, binary number is converted into decimal number, then voltage vector V27, V25, V31 respectively correspond space voltage vector V11, V9, V15；

As triple harmonic current error vector Δ i_zWhen positioned at sector 1., Δ i can be made_zReduced voltage vector has: space voltage arrow Measure V13, space voltage vector V1, space voltage vector V12, space voltage vector V9, space voltage vector V15, space voltage Vector V25, space voltage vector V11, space voltage vector V8, space voltage vector V3, if stator magnetic linkage vector ψ at this time_sPosition In sector 10. in, while increase magnetic linkage amplitude, then Δ ψ_s=1, electromagnetic torque improves, then Δ T_e=1, meet conditions above Voltage vector has: space voltage vector V9, space voltage vector V25, and due in α β plane, space voltage vector V25 is to turning The control effect of square and magnetic linkage is better than space voltage vector V9, therefore selects space voltage vector for V25, works as ψ_sPositioned at other When sector and so on.

Technical field

The present invention relates to a kind of fault-tolerant Direct Torque Controls of motor open-circuit fault, especially five-phase PMSM Fault-tolerant Direct Torque Control.The field having higher requirements suitable for the reliability to motor such as aerospace, electric car It closes.

Background technique

After motor driven systems break down, there is obvious pulsation in motor asymmetric operating, output torque, and noise obviously increases Add, systematic entirety can deteriorate, or even can not work, and seriously endanger production safety, therefore fault-tolerant energy when motor system fault Power is extremely important.

Direct Torque Control (DTC) technology is the control mode that a kind of structure is simple, parameter relies on less, torque response is fast. Existing DTC strategy can not inhibit motor system fault to the influence of motor output torque performance, significantly reduce five phase permanent magnetism The performance of synchronous motor DTC system.Therefore, the excellent torque performance of DTC can be played and improve the fault-tolerant of system reliability Strategy becomes one of high reliability area research hot spot.

Currently, the fault-tolerant Strategy of Direct Torque Control research for permanent magnet synchronous motor focuses mostly in open-circuit fault, In " the single-phase fault-tolerant Study on direct torque control technology of open circuit of five-phase induction motor " (the Open phase fault- delivered on IEEE tolerant direct torque control technique for five-phase induction motor Drives the fault-tolerant Strategy of Direct Torque Control based on Virtual Space voltage vector table, but the single-phase open-circuit fault of motor) are proposed Selectable Virtual Space voltage vector is reduced afterwards, is caused the magnetic linkage of motor to be pulsed and is increased, and output torque is greater than normal operation Situation.

Summary of the invention

Directly turn the object of the present invention is to provide a kind of five-phase PMSM based on New Fault-tolerant switch list is fault-tolerant Square control method, to solve that five-phase PMSM torque pulsation in single-phase open-circuit fault is big and bad dynamic performance is asked Topic.

The invention proposes a kind of New Fault-tolerant switch lists based on Virtual Space voltage vector, make motor normal and single It can be operated normally under phase open-circuit fault, ensure the fault-tolerance and reliability of electric system.The technical solution adopted by the present invention It is: when single-phase open-circuit fault occurs for five-phase PMSM, selects suitable Virtual Space voltage vector composition is fault-tolerant to open Table is closed, so that motor is operated with failure, the Virtual Space voltage vector in simultaneous failure tolerance switch list also can control five phase permanent-magnet synchronous Motor failure-free operation.The present invention makes motor still keep good output torque and dynamic response performance under single-phase open-circuit fault Under conditions of, without repeating the judgement of sector and the selection of Virtual Space vector.

A kind of fault-tolerant Direct Torque Control of five-phase PMSM based on New Fault-tolerant switch list, including it is following Step:

Step 1, the mathematical model under the single-phase open circuit of five-phase PMSM is established, the flux linkage equations of motor are obtained and is turned Moment equation；

Step 2, by revised flux linkage equations and torque equation, stator magnetic linkage ψ is calculated_sWith torque T_eReal-time estimation Value, by given torque T_e ^*With estimation torque T_eΔ T is obtained as difference_e, by given magnetic linkage ψ_s ^*With estimation magnetic linkage ψ_sΔ ψ is obtained as difference_s, Respective symbol function is obtained by hystersis controller；

Step 3, by α β plane and z₁z₂Plane is divided into ten sectors, and the center line with two neighboring big vector is Line of demarcation, 36 ° divide a sector into, and carry out label, stator magnetic linkage vector ψ to sector_sIn α β plane, triple harmonic current error Δi_zIn z₁z₂Plane, each sector correspond to corresponding space voltage vector；

Step 4, according to torque transient deviation Δ T_eWith stator magnetic linkage transient deviation Δ ψ_s, in conjunction with triple harmonic current error Δi_zControl and sector where stator magnetic linkage vector are chosen corresponding space voltage vector in fault-tolerant switch list and are realized to motor turn Square and stator magnetic linkage directly control；

Step 5, fault-tolerant switch list is applied in normal five-phase PMSM system, is realized to torque and stator Magnetic linkage directly controls.

Further, in the step 1, mathematical model is as follows when five-phase PMSM A phase open-circuit fault:

Flux linkage equations:

Torque equation:

In formula: i_α、i_β、ψ_α、ψ_βThe respectively component of electric current and stator magnetic linkage in α β plane, L_smFor magnetizing inductance, ψ_fFor Permanent magnet flux linkage amplitude, θ are rotor position angle, and p is number of pole-pairs.

Further, in the step 2, revised flux linkage equations are as follows:

Revised torque equation:

By stator magnetic linkage under open-circuit fault α axis component amplitude increase to motor operate normally when ψ_αAmplitude is identical, β axis Stator magnetic linkage remains unchanged, then the electric current before and after failure on α β coordinate system is identical, and torque equation is constant, i.e. stator magnetomotive force track It is constant, so as to realize the unperturbed fault-tolerant operation of motor.

Further, in the step 3, ignore the leakage inductance of motor, the expression formula of triple harmonic current error are as follows:

In formula: u_z、i_zRespectively third harmonic voltage vector and current phasor, u^* _z、i^* _zRespectively given triple-frequency harmonics electricity Press vector and its corresponding current phasor, Δ i_z=i^* _z-i_zFor triple harmonic current error vector；R_sFor phase winding resistance；

Five-phase PMSM is under single-phase open-circuit fault, the corresponding sky in each sector in the one-dimensional space and three-dimensional space Between voltage vector may be expressed as:

In formula: V_s ¹、V_s ³Respectively indicate the space voltage vector in the one-dimensional space and three-dimensional space；U_dcIt is expressed as inverter The voltage of voltage source；S_i(i=B, C, D, E) respectively indicates the switch state of the every phase bridge arm of inverter, S_iWhen=1, corresponding bridge is indicated The upper tube of arm is open-minded, down tube shutdown, S_iWhen=0, indicate that the down tube of corresponding bridge arm is open-minded, upper tube shutdown.

Further, in the step 3, when motor A phase is opened a way, in order to realize virtual stator magnetic linkage, electromagnetic torque simultaneously And triple harmonic current control errors, the specific choice method of space voltage vector are as follows:

1) according to z₁z₂Triple harmonic current error vector Δ i in plane_zLocating sector determines that one group can be allowed to reduce Space voltage vector；

2) judge virtual stator magnetic linkage vector ψ_sLocating sector, and acted on according to each voltage vector in this analysis 1), that is, draw The effect for playing virtual stator magnetic linkage amplitude and electromagnetic torque variation, selects relevant voltage vector；

3) according to analysis 2) as a result, list obtains the switching vector selector table for inhibiting triple-frequency harmonics, virtually according to table realization Stator magnetic linkage amplitude and electromagnetic torque track its given value, while by triple harmonic current error vector Δ i_zControl is zero；

As triple harmonic current error vector Δ i_zWhen positioned at sector 1., Δ i can be made_zReduced voltage vector has: space electricity Press vector V13, space voltage vector V1, space voltage vector V9, space voltage vector V15, space voltage vector V11, space Voltage vector V8, if stator magnetic linkage vector ψ at this time_sPositioned at sector 1. in, while increase magnetic linkage amplitude, then Δ ψ_s=1, electricity Magnetic torque improves, then Δ T_e=1, meeting conditions above voltage vector has: space voltage vector V8, space voltage vector V13；By In in α β plane, space voltage vector V8 is better than space voltage vector V13 to the control effect of torque and magnetic linkage, therefore selects Selecting space voltage vector is V8；If stator magnetic linkage vector ψ at this time_sPositioned at sector 10. in, while reduce magnetic linkage amplitude, then Δ ψ_s=-1, electromagnetic torque reduce, then Δ T_e=-1 can make Δ i_zReduced voltage vector only has V15, works as ψ_sPositioned at other sectors When and so on.

Further, in the step 5, fault-tolerant switch list is realized under five-phase PMSM A phase open-circuit fault to electricity After the directly controlling of machine torque and stator magnetic linkage, which can be used to control five-phase PMSM failure-free operation, Inhibit triple harmonic current；

When motor A phase is opened a way, S is used_B—S_ETetrad is numbered as voltage vector；When motor operates normally When, use S_A—S_EFive bits are numbered as voltage vector, binary number are converted into decimal number, then voltage vector V27, V25, V31 respectively correspond space voltage vector V11, V9, V15；

As triple harmonic current error vector Δ i_zWhen positioned at sector 1., Δ i can be made_zReduced voltage vector has: space electricity Press vector V13, space voltage vector V1, space voltage vector V12, space voltage vector V9, space voltage vector V15, space Voltage vector V25, space voltage vector V11, space voltage vector V8, space voltage vector V3, if stator magnetic linkage vector at this time ψ_sPositioned at sector 10. in, while increase magnetic linkage amplitude, then Δ ψ_s=1, electromagnetic torque improves, then Δ T_e=1, it is more than satisfaction Condition voltage vector has: space voltage vector V9, space voltage vector V25, due in α β plane, space voltage vector V25 Space voltage vector V9 is better than to the control effect of torque and magnetic linkage, therefore selects space voltage vector for V25, works as ψ_sIt is located at When other sectors and so on.

Fault-tolerant switch list proposed by the invention can be not only used for the fault-tolerant of the single-phase open-circuit fault of electric system and directly turn Square control, can be also used for the Direct Torque Control of fault-free motor, without repartitioning sector and selection Virtual Space voltage Vector enormously simplifies the design of switch list.

The invention has the following advantages:

1, it using the New Fault-tolerant switch list in the present invention, can be realized simultaneously to the single-phase open circuit of five-phase PMSM The even running of failure and non-failure conditions controls, and avoids the second selecting of sector repartitioned with space voltage vector, Greatly simplify the design of switch list.

2, the fault-tolerant Strategy of Direct Torque Control based on fault-tolerant switch list in the present invention, it is electric when guaranteeing single-phase open-circuit fault Under the premise of machine output torque is consistent under normal condition, torque ripple after capable of obviously inhibiting the single-phase open-circuit fault of motor makes Motor has the dynamic property as before failure, therefore motor still has excellent dynamic property under open fault condition And steady-state performance.

3, compared to traditional switch table, the New Fault-tolerant switch list in the present invention can effectively inhibit triple-frequency harmonics, reduce electricity The fluctuation of stream and torque, the performance of lifting system.

Detailed description of the invention

Fig. 1 is the fault-tolerant direct Torque Control block diagram under the single-phase open-circuit fault of five-phase PMSM；

Fig. 2 is distribution of the five-phase PMSM non-failure conditions down space voltage vector in a peacekeeping three-dimensional space Figure；It (a) is alpha-beta fundamental wave subspace；(b)z₁-z₂Subspace；

Fig. 3 is distribution of the five-phase PMSM A phase open circuit situation down space voltage vector in a peacekeeping three-dimensional space Figure；It (a) is alpha-beta fundamental wave subspace；(b)z₁-z₂Subspace；

Fig. 4 is the electric current and torque profile figure under motor failure-free operation, and (a) is that current waveform (b) is torque profile；

Fig. 5 be motor A phase open-circuit fault without fault-tolerant operation when electric current and torque profile figure, (a) is that current waveform (b) is Torque profile；

Fig. 6 be motor A phase open-circuit fault when using in the present invention based on the fault-tolerant Direct torque of New Fault-tolerant switch list Electric current and torque profile when system strategy operation, (a) is that current waveform (b) is torque profile；

Fig. 7 is the electric current and torque profile figure when being run under motor failure-free operation using fault-tolerant switch list of the invention, (a) It is torque profile for current waveform (b).

Specific embodiment

Below in conjunction with the attached drawing in the present invention, a specific embodiment of the invention is fully described by.Pass through ginseng The embodiment for examining attached drawing description is exemplary, and for explaining only the invention, and is not considered as limiting the invention.

A kind of fault-tolerant direct Torque Control block diagram under five-phase PMSM open-circuit fault is as shown in Figure 1, root According to magnetomotive force principle of invariance before and after failure, establish the mathematical model of motor under malfunction, by revised flux linkage equations and The stator magnetic linkage ψ of torque equation calculating motor_sWith torque T_eReal-time estimation value, the given torque T obtained after PI is adjusted_e ^*With Estimate torque T_eΔ T is obtained as difference_e, by given magnetic linkage ψ_s ^*With estimation magnetic linkage ψ_sΔ ψ is obtained as difference_s, according to torque transient deviation Δ T_eWith stator magnetic linkage transient deviation Δ ψ_s, corresponding space electricity in fault-tolerant switch list is chosen in the sector in conjunction with where stator magnetic linkage vector Vector is pressed, realization directly controls motor torque and stator magnetic linkage.