CN105429560A - Axial magnetic flux switching permanent magnet motor fault tolerance control method - Google Patents

Abstract

The invention discloses an axial magnetic flux switching permanent magnet motor fault tolerance control method. The method is characterized by detecting an actual current of each phase winding of an axial magnetic flux switching permanent magnet motor, determining whether each phase winding has a fault, during normal operation, using an AFFSPM motor vector control system with id=0 so that a stator current and a rotor magnetic field are mutually independent; when there is an open circuit fault, according to a fault switch state, adjusting other normal winding currents under a corresponding fault state; when there is a short circuit fault and a current exceeds a limited current, a short circuit fault phase is disconnected and using a fault tolerance control strategy under an open circuit fault state. In the invention, aiming at a structure characteristic of a motor itself, torque output performance of the motor before and after the different open circuit faults is not changed; a guarantee is provided for fault tolerance operation; and an axial magnetic-field magnetic flux switching motor possesses high reliability and high power density.

Description

A kind of axial magnetic flux switch permanent magnet motor failure tolerant control method

Technical field

The present invention relates to a kind of failure tolerant control method, particularly a kind of axial magnetic flux switch permanent magnet motor failure tolerant control method.

Background technology

Along with the range of application of motor in fields such as aviation, traffic military affairs constantly expands, the integrity problem of motor driven systems obtains association area scholar and pays close attention to more and more widely.Flux switch permanent magnet motor (FSPMM) is a kind of stator permanent magnet brushless electric machine, due to rotor structure simple rigid, has the features such as high power density, high torque density and high efficiency, obtains the extensive research of scholar in recent years.

Southeast China University professor Lin Mingyao proposes a kind of axial magnetic field flux switch permanent magnet motor (AFFSPMM) on this basis, this motor rotor construction is simple, axial dimension is short, and torque density is high, is particularly suitable for the drive motors requirement of straight drive electric automobile.But in order to ensure the safe operation of electric automobile under failure condition, the fault-tolerance of AFFSPM motor is very important.In recent years, by Modular Structure Design, optimize number of pole-pairs, add the modes such as redundancy winding and the fault freedom that magnetic flux switches fault tolerant permanent magnet machine is improved.But be not also suggested about the faults-tolerant control strategy under AFFSPM electrical fault state.

Summary of the invention

Technical problem to be solved by this invention is to provide a kind of axial magnetic flux switch permanent magnet motor failure tolerant control method.

For solving the problems of the technologies described above, the technical solution adopted in the present invention is:

A kind of axial magnetic flux switch permanent magnet motor failure tolerant control method, is characterized in that: detection axis, to each phase winding actual current of flux switch permanent magnet motor, judging every phase winding whether fault, when normally running, adopting i _dthe AFFSPM motor vector control system of=0, make stator current and rotor field separate; When open circuit fault, according to other the normal winding currents under breakdown switch status adjustment corresponding failure state; When short trouble, electric current goes beyond the limit of electric current, disconnects short trouble phase, takes the faults-tolerant control strategy under open circuit fault state.

Further, under described open circuit fault state, regulate the method for the normal winding current of two covers, torque performance when making the output torque performance of motor under malfunction substantially maintain normal operation.

Further, the method that described open circuit fault state lowers current comprises, and obtains actual speed n and the rotor position of three-phase AFFSPM motor _e, by the actual speed n of motor and given rotating speed n ^*compare, and carry out obtaining given torque after PI regulates to comparison signal, obtain armature supply dq axle component set-point i according to given torque _d ^*and i _q ^*, to the direct-axis current set-point i obtained _d ^*with quadrature axis current set-point i _q ^*by obtaining each phase winding given value of current value after Coordinate Conversion;

Under normal condition, the three-phase current equation of AFFSPM motor:

$\left\{\begin{array}{c}{I}_{a1}=I_m\cos \left(\mathrm{\θ}\right)\\ I_{b1}=I_m\cos (\mathrm{\θ}-2\mathrm{\π}/3)\\ I_{c1}=I_m\cos (\mathrm{\θ}+2\mathrm{\π}/3)\\ I_{a2}=I_m\cos \left(\mathrm{\θ}\right)\\ I_{b2}=I_m\cos (\mathrm{\θ}-2\mathrm{\π}/3)\\ I_{c2}=I_m\cos (\mathrm{\θ}+2\mathrm{\π}/3)\end{array}\right.---\left(1\right)$

Whole magnetomotive force (TMMF) expression formula is:

TMMF＝MMF _a+MMF ^b+MMF _c

(2)

＝NI _a1+αNI _b1+α ²NI _c1+NI _a2+αNI _b2+α ²NI _c2

Wherein: θ is electrical degree, I _j1, I _j2(j=a, b, c) represents the phase current in stator 1 and stator 2 respectively, I _mfor the amplitude of three-phase current, α equals 1 ∠ 120 °;

Changed by dq/abc, current equation can be expressed as:

$\left\{\begin{array}{c}{I}_{a1}={I_d}^{*}\cos \left(\mathrm{\θ}\right)-{I_q}^{*}\sin \left(\mathrm{\θ}\right)\\ I_{b1}={I_d}^{*}\cos (\mathrm{\θ}-2\mathrm{\π}/3)-{I_q}^{*}\sin (\mathrm{\θ}-2\mathrm{\π}/3)\\ I_{c1}={I_d}^{*}\cos (\mathrm{\θ}+2\mathrm{\π}/3){I_q}^{*}\sin (\mathrm{\θ}+2\mathrm{\π}/3)\\ I_{a2}={I_d}^{*}\cos \left(\mathrm{\θ}\right)-{I_q}^{*}\sin \left(\mathrm{\θ}\right)\\ I_{b2}={I_d}^{*}\cos (\mathrm{\θ}-2\mathrm{\π}/3)-{I_q}^{*}\sin (\mathrm{\θ}-2\mathrm{\π}/3)\\ I_{c2}={I_d}^{*}\cos (\mathrm{\θ}+2\mathrm{\π}/3){I_q}^{*}\sin (\mathrm{\θ}+2\mathrm{\π}/3)\end{array}\right.---\left(3\right)$

Open circuit fault judges main Types:

(1) when the open circuit of A1 winding, the current amplitude supposing now normally to run phase is I _m', then the expression formula of phase current is:

$\left\{\begin{array}{c}{I}_{a1}=0\\ I_{b1}={I_m}^{\′}\cos (\mathrm{\θ}-2\mathrm{\π}/3+\mathrm{\α})\\ I_{c1}={I_m}^{\′}\cos (\mathrm{\θ}+2\mathrm{\π}/3+\mathrm{\β})\\ I_{a2}=I_m\cos \left(\mathrm{\θ}\right)\\ I_{b2}=I_m\cos (\mathrm{\θ}-2\mathrm{\π}/3)\\ I_{c2}=I_m\cos (\mathrm{\θ}+2\mathrm{\π}/3)\end{array}\right.---\left(4\right)$

Wherein, α, β are the skew electrical degree of B1, C1 phase respectively.Formula (4) is brought in (2), obtains:

$\begin{array}{c}{\mathrm{TMMF}}^{\′}={{\mathrm{TMMF}}_1}^{\′}+{{\mathrm{TMMF}}_2}^{\′}\\ =-{{\mathrm{NI}}_m}^{\′}\cos (\mathrm{\θ}+\frac{\mathrm{\α}+\mathrm{\β}}{2})\[-\frac{1}{2}\cos \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)+\frac{\sqrt{3}}{2}\sin \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)\]+\frac{3}{2}{\mathrm{NI}}_m\cos \left(\mathrm{\θ}\right)\\ -j\sqrt{3}{{\mathrm{NI}}_m}^{\′}\sin (\mathrm{\θ}+\frac{\mathrm{\α}+\mathrm{\β}}{2})\[-\frac{\sqrt{3}}{2}\cos \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)-\frac{1}{2}\sin \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)\]+j\frac{3}{2}{\mathrm{NI}}_m\sin \left(\mathrm{\θ}\right)\end{array}---\left(5\right)$

In order to keep the TMMF before and after fault constant, following condition must be met:

$\left\{\begin{array}{c}-{{\mathrm{NI}}_m}^{\′}\cos (\mathrm{\θ}+\frac{\mathrm{\α}+\mathrm{\β}}{2})\[-\frac{1}{2}\cos \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)+\frac{\sqrt{3}}{2}\sin \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)\]=\frac{3}{2}{\mathrm{NI}}_m\cos \left(\mathrm{\θ}\right)\\ -j\sqrt{3}{{\mathrm{NI}}_m}^{\′}\sin (\mathrm{\θ}+\frac{\mathrm{\α}+\mathrm{\β}}{2})\[-\frac{\sqrt{3}}{2}\cos \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)-\frac{1}{2}\sin \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)\]=j\frac{3}{2}{\mathrm{NI}}_m\sin \left(\mathrm{\θ}\right)\end{array}\right.---\left(6\right)$

Be simplified to:

$\left\{\begin{array}{c}\mathrm{\α}-\mathrm{\β}=-\frac{\mathrm{\π}}{3}\\ \mathrm{\α}+\mathrm{\β}=0\end{array}\right.---\left(7\right)$

Formula (7) is brought in (6), can obtain:

$\{\begin{array}{c}\mathrm{\α}=-\frac{\mathrm{\π}}{6}\\ \mathrm{\β}=\frac{\mathrm{\π}}{6}\\ {I_m}^{\′}=\sqrt{3}{I}_m\end{array}---\left(8\right)$

So when A1 winding generation open circuit fault, formula (4) can formulate (9), as can be seen from formula (9), can guarantee that magnetomotive force is constant by the current amplitude and phase angle changing normal winding;

$\left\{\begin{array}{c}{I}_{a1}=0\\ I_{b1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}-5\mathrm{\π}/6)-{I_q}^{*}\sin (\mathrm{\θ}-5\mathrm{\π}/6)\]\\ I_{c1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}+5\mathrm{\π}/6)-{I_q}^{*}\sin (\mathrm{\θ}+5\mathrm{\π}/6)\]\\ I_{a2}=I_m\[{I_d}^{*}\cos \left(\mathrm{\θ}\right)-{I_q}^{*}\sin \left(\mathrm{\θ}\right)\]\\ I_{b2}=I_m\[{I_d}^{*}\cos (\mathrm{\θ}-\frac{2\mathrm{\π}}{3})-{I_q}^{*}\sin (\mathrm{\θ}-\frac{2\mathrm{\π}}{3})\]\\ I_{c2}=I_m\[{I_d}^{*}\cos (\mathrm{\θ}+\frac{2\mathrm{\π}}{3})-{I_q}^{*}\sin (\mathrm{\θ}+\frac{2\mathrm{\π}}{3})\]\end{array}\right.---\left(9\right)$

If A1 winding normally works, during any winding generation open circuit fault of A2, B1, B2, C1, C2, the similar formula of derivation (4)-(9) of fault-tolerant Current adjustment formula;

(2) when the open circuit of A1 and B2 winding, for keeping electromagnetic torque constant, now the electric current of motor is:

$\{\begin{array}{c}{I}_{a1}=0\\ I_{b1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}-5\mathrm{\π}/6)+{I_q}^{*}\sin (\mathrm{\θ}-5\mathrm{\π}/6)\]\\ I_{c1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}+5\mathrm{\π}/6)-{I_q}^{*}\sin (\mathrm{\θ}+5\mathrm{\π}/6)\]\\ I_{a2}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}+\frac{\mathrm{\π}}{6})-{I_q}^{*}\sin (\mathrm{\θ}+\frac{\mathrm{\π}}{6})\]\\ I_{b2}=0\\ I_{c2}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}+\frac{\mathrm{\π}}{2})-{I_q}^{*}\sin (\mathrm{\θ}+\frac{\mathrm{\π}}{2})\]\end{array}---\left(10\right)$

When disconnecting any one stator winding in A phase, B phase, any 2 phases of C phase, the similar formula of derivation (10) of fault-tolerant Current adjustment formula;

(3) when the open circuit of A1 and A2 winding, for keeping electromagnetic torque constant, now the electric current of motor is:

$\left\{\begin{array}{c}{I}_{a1}=0\\ I_{b1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}-5\mathrm{\π}/6)+{I_q}^{*}\sin (\mathrm{\θ}-5\mathrm{\π}/6)\]\\ I_{c1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}+5\mathrm{\π}/6)-{I_q}^{*}\sin (\mathrm{\θ}+5\mathrm{\π}/6)\]\\ I_{a2}=0\\ I_{b2}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}-5\mathrm{\π}/6)+{I_q}^{*}\sin (\mathrm{\θ}-5\mathrm{\π}/6)\]\\ I_{c2}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}+5\mathrm{\π}/6)-{I_q}^{*}\sin (\mathrm{\θ}+5\mathrm{\π}/6)\]\end{array}\right.---\left(11\right)$

When all there is open circuit fault in B phase, C phase two stator winding, the similar formula of derivation (11) of fault-tolerant Current adjustment formula.

Further, described axial magnetic flux switch permanent magnet motor has 2 groups of armature winding, not only increase the Driving Torque of motor, and when a phase armature winding breaks down, can originally organize normal armature winding and another group armature winding electric current by cooperation control, realize the normal operation under electrical fault.

The present invention compared with prior art, have the following advantages and effect: a kind of axial magnetic flux switch permanent magnet motor failure tolerant control method of the present invention is for this motor own structural characteristics, before and after making the different open circuit fault of motor, torque output performance is substantially constant, for fault-tolerant operation is given security, axial magnetic field flux switch motor is made to have high reliability, high power density.

Accompanying drawing explanation

Fig. 1 is the Systematical control block diagram of a kind of axial magnetic flux switch permanent magnet motor failure tolerant control method of the present invention.

Fig. 2 is the schematic diagram of axial magnetic field flux switch permanent magnet motor.

1-stator 1,2-rotor, 3-rotor pole, 4-stator 2,5-armature winding, 6-center tooth, 7-permanent magnet, 8-" E " iron-core, 9-stator tooth in figure.

Fig. 3 is the winding schematic diagram of axial magnetic field flux switch permanent magnet motor.

Fig. 4 is electric current under axial magnetic field flux switch permanent magnet motor normal operating condition and torque profile figure.

Fig. 5 is the torque profile figure under the different open circuit fault of axial magnetic field flux switch permanent magnet motor.

Fig. 6 electric current that to be axial magnetic field flux switch permanent magnet motor carry out when there is A1 winding open circuit fault after faults-tolerant control and torque profile figure.

Fig. 7 electric current that to be axial magnetic field flux switch permanent magnet motor carry out when there is A1 and B2 winding open circuit fault after faults-tolerant control and torque profile figure.

Fig. 8 electric current that to be axial magnetic field flux switch permanent magnet motor carry out when there is A1 and A2 winding open fault after faults-tolerant control and torque profile figure.

Embodiment

Below by embodiment, the present invention is described in further detail, and following examples are explanation of the invention and the present invention is not limited to following examples.

A kind of axial magnetic flux switch permanent magnet motor failure tolerant control method of the present invention, according to the type detecting electric current failure judgement, thus selects control strategy.During normal operation, adopt i _dthe vector control strategy of=0; If winding generation open circuit fault, then according to open circuit fault type, take corresponding faults-tolerant control, regulate the electric current of normal winding; The fault if winding is short-circuited, then disconnect this corresponding windings, then adopts the faults-tolerant control strategy of corresponding open circuit fault.AFFSPM motor has 2 groups of armature winding, not only increase the Driving Torque of motor, and when a phase armature winding breaks down, normal armature winding and another group armature winding electric current can be originally organized by cooperation control, realize the normal operation under electrical fault, reduce torque pulsation, improve motor runnability.

The fault-tolerant control system of the novel axial magnetic field flux switch permanent magnet motor shown in Fig. 1.Comprise: the actual speed n and the rotor position that obtain three-phase AFFSPM motor _e; By the actual speed n of motor and given rotating speed n ^*compare, and carry out obtaining given torque after PI regulates to comparison signal; Armature supply dq axle component set-point i is obtained according to given torque _d ^*and i _q ^*; To the direct-axis current set-point i obtained _d ^*with quadrature axis current set-point i _q ^*by obtaining each phase winding given value of current value after Coordinate Conversion; Detect each phase winding actual current of three-phase AFFSPM motor; Each phase winding curent change according to motor judges whether arbitrary phase winding open circuit or short trouble occur, and as fault-free, then selects the control strategy under normal operation; If generation open circuit fault, then select faults-tolerant control strategy, utilize the adjustment formula of phase induced current under different open circuit fault state to draw each phase winding given value of current value; If detect the fault (namely electric current goes beyond the limit of value) that is short-circuited, then disconnect this phase winding, adopt the Current adjustment formula under corresponding open circuit fault state to draw each phase winding given value of current value.

Under normal condition, the three-phase current equation of AFFSPM motor:

$\left\{\begin{array}{c}{I}_{a1}=I_m\cos \left(\mathrm{\θ}\right)\\ I_{b1}=I_m\cos (\mathrm{\θ}-2\mathrm{\π}/3)\\ I_{c1}=I_m\cos (\mathrm{\θ}+2\mathrm{\π}/3)\\ I_{a2}=I_m\cos \left(\mathrm{\θ}\right)\\ I_{b2}=I_m\cos (\mathrm{\θ}-2\mathrm{\π}/3)\\ I_{c2}=I_m\cos (\mathrm{\θ}+2\mathrm{\π}/3)\end{array}\right.---\left(1\right)$

Whole magnetomotive force (TMMF) expression formula is:

TMMF＝MMF _a+MMF _b+MMF _c

＝NI _a1+αNI _b1+α ²NI _c1+NI _a2+αNI _b2+α ²NI _c2(2)

Wherein: θ is electrical degree, I _j1, I _j2(j=a, b, c) represents the phase current in stator 1 and stator 2 respectively, I _mfor the amplitude of three-phase current, α equals 1 ∠ 120 °.

Changed by dq/abc, current equation can be expressed as:

$\left\{\begin{array}{c}{I}_{a1}={I_d}^{*}\cos \left(\mathrm{\θ}\right)-{I_q}^{*}\sin \left(\mathrm{\θ}\right)\\ I_{b1}={I_d}^{*}\cos (\mathrm{\θ}-2\mathrm{\π}/3)-{I_q}^{*}\sin (\mathrm{\θ}-2\mathrm{\π}/3)\\ I_{c1}={I_d}^{*}\cos (\mathrm{\θ}+2\mathrm{\π}/3){I_q}^{*}\sin (\mathrm{\θ}+2\mathrm{\π}/3)\\ I_{a2}={I_d}^{*}\cos \left(\mathrm{\θ}\right)-{I_q}^{*}\sin \left(\mathrm{\θ}\right)\\ I_{b2}={I_d}^{*}\cos (\mathrm{\θ}-2\mathrm{\π}/3)-{I_q}^{*}\sin (\mathrm{\θ}-2\mathrm{\π}/3)\\ I_{c2}={I_d}^{*}\cos (\mathrm{\θ}+2\mathrm{\π}/3){I_q}^{*}\sin (\mathrm{\θ}+2\mathrm{\π}/3)\end{array}\right.---\left(3\right)$

Open circuit fault judges main Types:

(1) when the open circuit of A1 winding, the current amplitude supposing now normally to run phase is I _m', then the expression formula of phase current is:

$\left\{\begin{array}{c}{I}_{a1}=0\\ I_{b1}={I_m}^{\′}\cos (\mathrm{\θ}-2\mathrm{\π}/3+\mathrm{\α})\\ I_{c1}={I_m}^{\′}\cos (\mathrm{\θ}+2\mathrm{\π}/3+\mathrm{\β})\\ I_{a2}=I_m\cos \left(\mathrm{\θ}\right)\\ I_{b2}=I_m\cos (\mathrm{\θ}-2\mathrm{\π}/3)\\ I_{c2}=I_m\cos (\mathrm{\θ}+2\mathrm{\π}/3)\end{array}\right.---\left(4\right)$

Wherein, α, β are the skew electrical degree of B1, C1 phase respectively.Formula (4) is brought in (2), obtains:

$\begin{array}{c}{\mathrm{TMMF}}^{\′}={{\mathrm{TMMF}}_1}^{\′}+{{\mathrm{TMMF}}_2}^{\′}\\ =-{{\mathrm{NI}}_m}^{\′}\cos (\mathrm{\θ}+\frac{\mathrm{\α}+\mathrm{\β}}{2})\[-\frac{1}{2}\cos \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)+\frac{\sqrt{3}}{2}\sin \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)\]+\frac{3}{2}{\mathrm{NI}}_m\cos \left(\mathrm{\θ}\right)\\ -j\sqrt{3}{{\mathrm{NI}}_m}^{\′}\sin (\mathrm{\θ}+\frac{\mathrm{\α}+\mathrm{\β}}{2})\[-\frac{\sqrt{3}}{2}\cos \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)-\frac{1}{2}\sin \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)\]+j\frac{3}{2}{\mathrm{NI}}_m\sin \left(\mathrm{\θ}\right)\end{array}---\left(5\right)$

In order to keep the TMMF before and after fault constant, following condition must be met:

$\left\{\begin{array}{c}-{{\mathrm{NI}}_m}^{\′}\cos (\mathrm{\θ}+\frac{\mathrm{\α}+\mathrm{\β}}{2})\[-\frac{1}{2}\cos \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)+\frac{\sqrt{3}}{2}\sin \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)\]=\frac{3}{2}{\mathrm{NI}}_m\cos \left(\mathrm{\θ}\right)\\ -j\sqrt{3}{{\mathrm{NI}}_m}^{\′}\sin (\mathrm{\θ}+\frac{\mathrm{\α}+\mathrm{\β}}{2})\[-\frac{\sqrt{3}}{2}\cos \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)-\frac{1}{2}\sin \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)\]=j\frac{3}{2}{\mathrm{NI}}_m\sin \left(\mathrm{\θ}\right)\end{array}\right.---\left(6\right)$

Be simplified to:

$\left\{\begin{array}{c}\mathrm{\α}-\mathrm{\β}=-\frac{\mathrm{\π}}{3}\\ \mathrm{\α}+\mathrm{\β}=0\end{array}\right.---\left(7\right)$

Formula (7) is brought in (6), can obtain:

$\left\{\begin{array}{c}\mathrm{\α}=-\frac{\mathrm{\π}}{6}\\ \mathrm{\β}=\frac{\mathrm{\π}}{6}\\ {I_m}^{\′}=\sqrt{3}{I}_m\end{array}\right.---\left(8\right)$

So when A1 winding generation open circuit fault, formula (4) can formulate (9), as can be seen from formula (9), can guarantee that magnetomotive force is constant by the current amplitude and phase angle changing normal winding.

$\left\{\begin{array}{c}{I}_{a1}=0\\ I_{b1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}-5\mathrm{\π}/6)-{I_q}^{*}\sin (\mathrm{\θ}-5\mathrm{\π}/6)\]\\ I_{c1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}+5\mathrm{\π}/6)-{I_q}^{*}\sin (\mathrm{\θ}+5\mathrm{\π}/6)\]\\ I_{a2}=I_m\[{I_d}^{*}\cos \left(\mathrm{\θ}\right)-{I_q}^{*}\sin \left(\mathrm{\θ}\right)\]\\ I_{b2}=I_m\[{I_d}^{*}\cos (\mathrm{\θ}-\frac{2\mathrm{\π}}{3})-{I_q}^{*}\sin (\mathrm{\θ}-\frac{2\mathrm{\π}}{3})\]\\ I_{c2}=I_m\[{I_d}^{*}\cos (\mathrm{\θ}+\frac{2\mathrm{\π}}{3})-{I_q}^{*}\sin (\mathrm{\θ}+\frac{2\mathrm{\π}}{3})\]\end{array}\right.---\left(9\right)$

If A1 winding normally works, during any winding generation open circuit fault of A2, B1, B2, C1, C2, the similar formula of derivation (4)-(9) of fault-tolerant Current adjustment formula.

(2) when the open circuit of A1 and B2 winding, for keeping electromagnetic torque constant, now the electric current of motor is:

$\{\begin{array}{c}{I}_{a1}=0\\ I_{b1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}-5\mathrm{\π}/6)+{I_q}^{*}\sin (\mathrm{\θ}-5\mathrm{\π}/6)\]\\ I_{c1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}+5\mathrm{\π}/6)-{I_q}^{*}\sin (\mathrm{\θ}+5\mathrm{\π}/6)\]\\ I_{a2}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}+\frac{\mathrm{\π}}{6})-{I_q}^{*}\sin (\mathrm{\θ}+\frac{\mathrm{\π}}{6})\]\\ I_{b2}=0\\ I_{c2}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}+\frac{\mathrm{\π}}{2})-{I_q}^{*}\sin (\mathrm{\θ}+\frac{\mathrm{\π}}{2})\]\end{array}---\left(10\right)$

When disconnecting any one stator winding in A phase, B phase, any 2 phases of C phase, the similar formula of derivation (10) of fault-tolerant Current adjustment formula.

(3) when the open circuit of A1 and A2 winding, for keeping electromagnetic torque constant, now the electric current of motor is:

$\left\{\begin{array}{c}{I}_{a1}=0\\ I_{b1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}-5\mathrm{\π}/6)+{I_q}^{*}\sin (\mathrm{\θ}-5\mathrm{\π}/6)\]\\ I_{c1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}+5\mathrm{\π}/6)-{I_q}^{*}\sin (\mathrm{\θ}+5\mathrm{\π}/6)\]\\ I_{a2}=0\\ I_{b2}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}-5\mathrm{\π}/6)+{I_q}^{*}\sin (\mathrm{\θ}-5\mathrm{\π}/6)\]\\ I_{c2}=\sqrt{3}{I}_m\[{I_d}^{*}\cos (\mathrm{\θ}+5\mathrm{\π}/6)-{I_q}^{*}\sin (\mathrm{\θ}+5\mathrm{\π}/6)\]\end{array}\right.---\left(11\right)$

When all there is open circuit fault in B phase, C phase two stator winding, the similar formula of derivation (11) of fault-tolerant Current adjustment formula.

As shown in Figure 2, for a 6/14 rotor pole axis to magnetic field flux switch permanent magnet motor, this motor forms two air gap permanent magnet motor by two stators and a rotor.Rotor is placed between two stators.The structure of two stators is identical, and symmetrical about rotor.Each stator is made up of 6 " E " iron-cores, 6 permanent magnets, 6 armature coils, and permanent magnet is placed in the middle of two " E " iron-cores, circumferentially alternately magnetizes, and the symmetrical permanent magnet excitation direction of two stators is contrary; 6 windings in each stator around the home on permanent magnet and the stator tooth adjacent with permanent magnet are armature winding, and winding is diametrically in series composition one phase, successively 6 armature winding is divided into three-phase.A in Fig. 3 ₁₁and A ₁₂a phase winding A in stator 1 in series ₁, A ₂₁and A ₂₂a phase winding A in stator 2 in series ₂, A ₁and A ₂form AFFSPM motor A phase winding.In like manner, B phase, C phase winding is formed.Stator 1 and stator 2 there is 1 group of armature winding respectively, not only increase the Driving Torque of motor, and when a phase armature winding breaks down, normal armature winding and another group armature winding electric current can be originally organized by cooperation control, realize the normal operation under electrical fault, reduce torque pulsation, improve motor runnability.

According to the driving control system for electric machine of AFFSPM shown in Fig. 1, under MATLAB/SIMULINK environment, build simulation model, simulation result is as shown in Fig. 3-Fig. 7.The expression formula of torque pulsation coefficient is:

$K_T=\frac{T_{max}-T_{\min }}{T_{av}}\×100\%---\left(12\right)$

Figure 4 shows that the electric current under AFFSPM motor normal operating condition and torque profile figure.As can be seen from the figure: under normal circumstances, after 0.1s, AFFSPM motor stabilizing runs, and the peak value of phase current is close to 1A, and torque pulsation is about 10%.

Fig. 5 is the torque profile figure under the different open circuit fault of AFFSPM motor.A can be found out from Fig. 5 (a) ₁winding open circuit, torque pulsation increases to some extent than torque pulsation during normal operation, and motor reaches stable operation after 0.3s; Fig. 5 (b), (c) demonstrate: work as A ₁and B ₂during winding open circuit simultaneously, torque pulsation coefficient reaches 66.7%; And A ₁and A ₂during winding open circuit, torque pulsation coefficient even reaches 100%.

Fig. 6, Fig. 7, Fig. 8 carry out electric current after faults-tolerant control and torque profile figure when being respectively the open circuit of AFFSPM motor A1 winding, the open circuit of A1 and B2 winding, the open circuit of A1 and A2 winding; As can be seen from Fig. 6-Fig. 8, under different open circuit fault, adopt this faults-tolerant control strategy not only can improve the self-starting performance of motor, and Driving Torque maintains Driving Torque when normally working substantially, torque pulsation greatly reduces.

Above content described in this specification is only made for the present invention illustrating.Those skilled in the art can make various amendment or supplement or adopt similar mode to substitute to described specific embodiment; only otherwise depart from the content of specification of the present invention or surmount this scope as defined in the claims, protection scope of the present invention all should be belonged to.

Claims (4)

1. an axial magnetic flux switch permanent magnet motor failure tolerant control method, is characterized in that: detection axis, to each phase winding actual current of flux switch permanent magnet motor, judges every phase winding whether fault, when normally running, adopts i _dthe AFFSPM motor vector control system of=0, make stator current and rotor field separate; When open circuit fault, according to other the normal winding currents under breakdown switch status adjustment corresponding failure state; When short trouble, electric current goes beyond the limit of electric current, disconnects short trouble phase, takes the faults-tolerant control strategy under open circuit fault state.

2. according to a kind of axial magnetic flux switch permanent magnet motor failure tolerant control method according to claim 1, it is characterized in that: the method regulating the normal winding current of two covers under described open circuit fault state, torque performance when making the output torque performance of motor under malfunction substantially maintain normal operation.

3. according to a kind of axial magnetic flux switch permanent magnet motor failure tolerant control method according to claim 2, it is characterized in that: the method that described open circuit fault state lowers current comprises, obtain actual speed n and the rotor position of three-phase AFFSPM motor _e, by the actual speed n of motor and given rotating speed n ^*compare, and carry out obtaining given torque after PI regulates to comparison signal, obtain armature supply dq axle component set-point i according to given torque _d ^*and i _q ^*, to the direct-axis current set-point i obtained _d ^*with quadrature axis current set-point i _q ^*by obtaining each phase winding given value of current value after Coordinate Conversion;

Under normal condition, the three-phase current equation of AFFSPM motor:

$\left\{\begin{array}{c}{I}_{a1}=I_m\cos \left(\mathrm{\θ}\right)\\ I_{b1}=I_m\cos \left(\mathrm{\θ}-2\mathrm{\π}/3\right)\\ I_{c1}=I_m\cos \left(\mathrm{\θ}+2\mathrm{\π}/3\right)\\ I_{a2}=I_m\cos \left(\mathrm{\θ}\right)\\ I_{b2}=I_m\cos \left(\mathrm{\θ}-2\mathrm{\π}/3\right)\\ I_{c2}=I_m\cos \left(\mathrm{\θ}+2\mathrm{\π}/3\right)\end{array}\right.---\left(1\right)$

Whole magnetomotive force (TMMF) expression formula is:

TMMF＝MMF _a+MMF _b+MMF _c

(2)

＝NI _a1+αNI _b1+α ²NI _c1+NI _a2+αNI _b2+α ²NI _c2

Wherein: θ is electrical degree, I _j1, I _j2(j=a, b, c) represents the phase current in stator 1 and stator 2 respectively, I _mfor the amplitude of three-phase current, α equals 1 ∠ 120 °;

Changed by dq/abc, current equation can be expressed as:

$\left\{\begin{array}{c}{I}_{a1}={I_d}^{*}\cos \left(\mathrm{\θ}\right)-{I_q}^{*}\sin \left(\mathrm{\θ}\right)\\ I_{b1}={I_d}^{*}\cos \left(\mathrm{\θ}-2\mathrm{\π}/3\right)-{I_q}^{*}\sin \left(\mathrm{\θ}-2\mathrm{\π}/3\right)\\ I_{c1}={I_d}^{*}\cos \left(\mathrm{\θ}+2\mathrm{\π}/3\right)-{I_q}^{*}\sin \left(\mathrm{\θ}+2\mathrm{\π}/3\right)\\ I_{a2}={I_d}^{*}\cos \left(\mathrm{\θ}\right)-{I_q}^{*}\sin \left(\mathrm{\θ}\right)\\ I_{b2}={I_d}^{*}\cos \left(\mathrm{\θ}-2\mathrm{\π}/3\right)-{I_q}^{*}\sin \left(\mathrm{\θ}-2\mathrm{\π}/3\right)\\ I_{c2}={I_d}^{*}\cos \left(\mathrm{\θ}+2\mathrm{\π}/3\right)-{I_q}^{*}\sin \left(\mathrm{\θ}+2\mathrm{\π}/3\right)\end{array}\right.---\left(3\right)$

Open circuit fault judges main Types:

(1) when the open circuit of A1 winding, the current amplitude supposing now normally to run phase is I _m', then the expression formula of phase current is:

$\left\{\begin{array}{c}{I}_{a1}=0\\ I_{b1}={I_m}^{\′}\cos \left(\mathrm{\θ}-2\mathrm{\π}/3+\mathrm{\α}\right)\\ I_{c1}={I_m}^{\′}\cos \left(\mathrm{\θ}+2\mathrm{\π}/3+\mathrm{\β}\right)\\ I_{a2}=I_m\cos \left(\mathrm{\θ}\right)\\ I_{b2}=I_m\cos \left(\mathrm{\θ}-2\mathrm{\π}/3\right)\\ I_{c2}=I_m\cos \left(\mathrm{\θ}+2\mathrm{\π}/3\right)\end{array}\right.---\left(4\right)$

Wherein, α, β are the skew electrical degree of B1, C1 phase respectively.Formula (4) is brought in (2), obtains:

$\begin{array}{c}{\mathrm{TMMF}}^{\′}={{\mathrm{TMMF}}_1}^{\′}+{{\mathrm{TMMF}}_2}^{\′}\\ =-{{\mathrm{NI}}_m}^{\′}\cos \left(\mathrm{\θ}+\frac{\mathrm{\α}+\mathrm{\β}}{2}\right)\[-\frac{1}{2}\cos \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)+\frac{\sqrt{3}}{2}\sin \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)\]+\frac{3}{2}{\mathrm{NI}}_m\cos \left(\mathrm{\θ}\right)\\ -j\sqrt{3}{{\mathrm{NI}}_m}^{\′}\sin \left(\mathrm{\θ}+\frac{\mathrm{\α}+\mathrm{\β}}{2}\right)\[-\frac{\sqrt{3}}{2}\cos \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)-\frac{1}{2}\sin \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)\]+j\frac{3}{2}{\mathrm{NI}}_m\sin \left(\mathrm{\θ}\right)\end{array}---\left(5\right)$

In order to keep the TMMF before and after fault constant, following condition must be met:

$\left\{\begin{array}{c}-{{\mathrm{NI}}_m}^{\′}cos(\mathrm{\θ}+\frac{\mathrm{\α}+\mathrm{\β}}{2})\[-\frac{1}{2}cos\left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)+\frac{\sqrt{3}}{2}sin\left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)\]=\frac{3}{2}{\mathrm{NI}}_{m}cos\left(\mathrm{\θ}\right)\\ -j\sqrt{3}{{\mathrm{NI}}_m}^{\′}sin(\mathrm{\θ}+\frac{\mathrm{\α}+\mathrm{\β}}{2})\[-\frac{\sqrt{3}}{2}\cos \left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)-\frac{1}{2}sin\left(\frac{\mathrm{\α}-\mathrm{\β}}{2}\right)\]=j\frac{3}{2}{\mathrm{NI}}_{m}sin\left(\mathrm{\θ}\right)\end{array}\right.---\left(6\right)$

Be simplified to:

$\left\{\begin{array}{c}\mathrm{\α}-\mathrm{\β}=-\frac{\mathrm{\π}}{3}\\ \mathrm{\α}+\mathrm{\β}=0\end{array}\right.---\left(7\right)$

Formula (7) is brought in (6), can obtain:

$\left\{\begin{array}{c}\mathrm{\α}=-\frac{\mathrm{\π}}{6}\\ \mathrm{\β}=\frac{\mathrm{\π}}{6}\\ {I_m}^{\′}=\sqrt{3}{I}_m\end{array}\right.---\left(8\right)$

So when A1 winding generation open circuit fault, formula (4) can formulate (9), as can be seen from formula (9), can guarantee that magnetomotive force is constant by the current amplitude and phase angle changing normal winding;

$\left\{\begin{array}{c}{I}_{a1}=0\\ I_{b1}=\sqrt{3}{I}_m\[{I_d}^{*}cos(\mathrm{\θ}-5\mathrm{\π}/6)-{I_q}^{*}sin(\mathrm{\θ}-5\mathrm{\π}/6)\]\\ I_{c1}=\sqrt{3}{I}_m\[{I_d}^{*}cos(\mathrm{\θ}+5\mathrm{\π}/6)-{I_q}^{*}sin(\mathrm{\θ}+5\mathrm{\π}/6)\]\\ I_{a2}=I_m\[{I_d}^{*}cos\left(\mathrm{\θ}\right)-{I_q}^{*}sin\left(\mathrm{\θ}\right)\]\\ I_{b2}=I_m\[{I_d}^{*}cos(\mathrm{\θ}-\frac{2\mathrm{\π}}{3})-{I_q}^{*}\sin (\mathrm{\θ}-\frac{2\mathrm{\π}}{3})\]\\ I_{c2}=I_m\[{I_d}^{*}cos(\mathrm{\θ}+\frac{2\mathrm{\π}}{3})-{I_q}^{*}\sin (\mathrm{\θ}+\frac{2\mathrm{\π}}{3})\]\end{array}\right.---\left(9\right)$

If A1 winding normally works, during any winding generation open circuit fault of A2, B1, B2, C1, C2, the similar formula of derivation (4)-(9) of fault-tolerant Current adjustment formula;

(2) when the open circuit of A1 and B2 winding, for keeping electromagnetic torque constant, now the electric current of motor is:

$\left\{\begin{array}{c}{I}_{a1}=0\\ I_{b1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos \left(\mathrm{\θ}-5\mathrm{\π}/6\right)+{I_q}^{*}\sin \left(\mathrm{\θ}-5\mathrm{\π}/6\right)\]\\ I_{c1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos \left(\mathrm{\θ}+5\mathrm{\π}/6\right)-{I_q}^{*}\sin \left(\mathrm{\θ}+5\mathrm{\π}/6\right)\]\\ I_{a2}=\sqrt{3}{I}_m\[{I_d}^{*}\cos \left(\mathrm{\θ}+\frac{\mathrm{\π}}{6}\right)-{I_q}^{*}\sin \left(\mathrm{\θ}+\frac{\mathrm{\π}}{6}\right)\]\\ I_{b2}=0\\ I_{c2}=\sqrt{3}{I}_m\[{I_d}^{*}\cos \left(\mathrm{\θ}+\frac{\mathrm{\π}}{2}\right)-{I_q}^{*}\sin \left(\mathrm{\θ}+\frac{\mathrm{\π}}{2}\right)\]\end{array}\right.---\left(10\right)$

When disconnecting any one stator winding in A phase, B phase, any 2 phases of C phase, the similar formula of derivation (10) of fault-tolerant Current adjustment formula;

(3) when the open circuit of A1 and A2 winding, for keeping electromagnetic torque constant, now the electric current of motor is:

$\left\{\begin{array}{c}{I}_{a1}=0\\ I_{b1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos \left(\mathrm{\θ}-5\mathrm{\π}/6\right)+{I_q}^{*}\sin \left(\mathrm{\θ}-5\mathrm{\π}/6\right)\]\\ I_{c1}=\sqrt{3}{I}_m\[{I_d}^{*}\cos \left(\mathrm{\θ}+5\mathrm{\π}/6\right)-{I_q}^{*}\sin \left(\mathrm{\θ}+5\mathrm{\π}/6\right)\]\\ I_{a2}=0\\ I_{b2}=\sqrt{3}{I}_m\[{I_d}^{*}\cos \left(\mathrm{\θ}-5\mathrm{\π}/6\right)+{I_q}^{*}\sin \left(\mathrm{\θ}-5\mathrm{\π}/6\right)\]\\ I_{c2}=\sqrt{3}{I}_m\[{I_d}^{*}\cos \left(\mathrm{\θ}+5\mathrm{\π}/6\right)-{I_q}^{*}\sin \left(\mathrm{\θ}+5\mathrm{\π}/6\right)\]\end{array}\right.---\left(11\right)$

When all there is open circuit fault in B phase, C phase two stator winding, the similar formula of derivation (11) of fault-tolerant Current adjustment formula.

4. according to a kind of axial magnetic flux switch permanent magnet motor failure tolerant control method according to claim 1, it is characterized in that: described axial magnetic flux switch permanent magnet motor has 2 groups of armature winding, not only increase the Driving Torque of motor, and when a phase armature winding breaks down, can originally organize normal armature winding and another group armature winding electric current by cooperation control, realize the normal operation under electrical fault.