CN103427731B - A kind of short-circuit compensation control method of four-phase permanent-magnetic fault-tolerant motor - Google Patents

Abstract

The invention discloses a kind of short-circuit compensation control method of four-phase permanent-magnetic fault-tolerant motor, adopt concentratred winding, connect independently H bridge and drive inverter, to realize Fault Isolation completely.When a certain phase winding is short-circuited fault, larger short circuit current will be produced in this phase, cause motor unbalanced operation.Utilizing the torque principle of equal effects, by adjusting amplitude and the phase place of other healthy phases electric currents, making the electromagnetic torque that before and after fault, motor exports equal, to realize short trouble faults-tolerant control.

Description

A kind of short-circuit compensation control method of four-phase permanent-magnetic fault-tolerant motor

Technical field

The present invention relates to a kind of electric motor short circuit compensating control method, particularly a kind of short-circuit compensation control method of four-phase permanent-magnetic fault-tolerant motor.

Background technology

In recent years, along with developing rapidly of ac motor speed control technology, the many electricity of research and electric aircraft to have become in aviation field a very powerful and exceedingly arrogant problem.And one of key technology of how electric aircraft system is exactly the design of electric actuation system.Be widely used in the vital electrical drive systems such as aircraft brake, rudder face control and oil pump due to electric actuation system, once break down, fault rear motor phase-deficient operation, to larger fluctuation be there is in Driving Torque, produce larger machinery noise, the overall performance of system reduces greatly, even can not work, cause heavy losses.Therefore electric actuation system must have very strong security reliability and fault-tolerance, and research improves the control strategy of system reliability, reduces or avoids the loss because fault causes, being of great practical significance.

Since 20 century 70s, external scholar expands the research to motor driven systems reliability engineering, and achieves some achievements, from existing document, method mainly contains two kinds: adopt redundancy structure and improve System Fault Tolerance performance.Concrete realization means mainly contains the following aspects: research has the electric machine structure of fault freedom, the topological structure of exploitation high reliability drive circuit, the Intelligent Control Strategy of research high reliability.

Existing faults-tolerant control strategy, is only limitted to open fault, and algorithm is complicated, needs repeatedly complicated iteration just can draw the given electric current be finally applied on normal phase winding, the not easily software programming of whole control procedure.The present invention proposes a kind of simple, the faults-tolerant control strategy being applicable to short trouble easy to operate, substantially increases reliability and the fault-tolerance of system.

Summary of the invention

For problems of the prior art, the object of the present invention is to provide a kind of simple, effective faults-tolerant control strategy, make motor meet the short-circuit compensation control method of four-phase permanent-magnetic fault-tolerant motor operated with failure under the prerequisite of particular technology index.

In order to achieve the above object, the present invention by the following technical solutions: a kind of short-circuit compensation control method of four-phase permanent-magnetic fault-tolerant motor, step comprises:

1) the 4 phase permanent magnet fault tolerant motor described in is divided into A, B, C, D tetra-phase, is drawn at every phase winding two ends, independently H bridge inverter in connection, and takes heat isolation and physical isolation to power electronic device, performs step 2 afterwards);

2) utilize Hall current sensor to detect the electric current of each phase winding, perform step 3) afterwards;

3) when A phase winding current amplitude I being detected _am> I _mtime, I _mby amplitude alive when motor normally runs, known A phase is short-circuited fault, performs step 4); When B phase winding current amplitude I being detected _bm> I _mtime, namely B phase winding is short-circuited fault, performs step 5); When C phase winding current amplitude I being detected _cm> I _mtime, namely C phase winding is short-circuited fault, performs step 6); When D phase winding current amplitude I being detected _dm> I _mtime, namely D phase winding is short-circuited fault, performs step 7), works as I _am≤ I _mand I _bm≤ I _mand I _cm≤ I _mand I _dm≤ I _mtime, then perform step 2);

4) on DSP CONTROL H bridge inverter, the break-make adjustment B phase winding current amplitude of each thyristor is consistent with A phase winding amplitude of short circuit, when B phase winding current phase is normally run with A phase winding, current phase is consistent, and C, D two the current amplitude of phase winding be adjusted to C, D two phase winding normally run time 2 times of current amplitude, C, D two the current phase of phase winding remain unchanged, this method terminates;

5) on DSP CONTROL H bridge inverter, the break-make adjustment C phase winding current amplitude of each thyristor is consistent with B phase winding amplitude of short circuit, when C phase winding current phase is normally run with B phase winding, current phase is consistent, and A, D two the current amplitude of phase winding be adjusted to A, D two phase winding normally run time 2 times of current amplitude, A, D two the current phase of phase winding remain unchanged, this method terminates;

6) on DSP CONTROL H bridge inverter, the break-make adjustment D phase winding current amplitude of each thyristor is consistent with C phase winding amplitude of short circuit, when D phase winding current phase is normally run with C phase winding, current phase is consistent, and A, B two the current amplitude of phase winding be adjusted to A, B two phase winding normally run time 2 times of current amplitude, A, B two the current phase of phase winding remain unchanged, this method terminates;

7) on DSP CONTROL H bridge inverter, the break-make adjustment A phase winding current amplitude of each thyristor is consistent with D phase winding amplitude of short circuit, when A phase winding current phase is normally run with D phase winding, current phase is consistent, and B, C two the current amplitude of phase winding be adjusted to B, C two phase winding normally run time 2 times of current amplitude, B, C two the current phase of phase winding remain unchanged, this method terminates.

After adopting technique scheme, the present invention has following beneficial effect: adopt concentratred winding, connects independently H bridge and drives inverter, to realize Fault Isolation completely.When a certain phase winding is short-circuited fault, larger short circuit current will be produced in this phase, cause motor unbalanced operation.Utilizing the torque principle of equal effects, by adjusting amplitude and the phase place of other healthy phases electric currents, making the electromagnetic torque that before and after fault, motor exports equal, to realize short trouble faults-tolerant control.

Accompanying drawing explanation

Fig. 1 is the system block diagram of fault-tolerant control system.

Fig. 2 is 4 phase permanent magnet fault tolerant electric machine structure figure

Fig. 3 is the topological structure of fault tolerant permanent magnet machine drive circuit.

Fig. 4 is the current waveform added when normally running of 4 phase permanent magnet fault tolerant motor.

Fig. 5 is the electromagnetic torque waveform that 4 phase permanent magnet fault tolerant motor exports when normally running.

Fig. 6 be A phase winding be short-circuited fault time short circuit current waveform.

Fig. 7 is the electromagnetic torque waveform of A phase winding when breaking down.

Fig. 8 is the fault-tolerant current waveform of the B phase of A phase winding when breaking down.

Fig. 9 is the fault-tolerant current waveform of A phase winding C, D phase when breaking down.

Figure 10 is that A phase winding is short-circuited the electromagnetic torque waveform after failure tolerant.

Embodiment

Below in conjunction with specification drawings and specific embodiments, the present invention is further explained.

As shown in Figure 1, the system block diagram of fault-tolerant control system of the present invention, i _a ^*, i _b ^*, i _c ^*, i _d ^*be respectively the instruction current of A, B, C, D phase, i _a, i _b, i _c, i _dbe respectively the actual current of A, B, C, D phase detected by Hall current sensor, try to achieve i by adder ^*the value of-i, it can be used as the input of Hysteresis Current comparator, is carried out the turn-on and turn-off of driving power device by the output of Hysteresis Current comparator.

As shown in Figure 2, the 4 phase permanent magnet fault tolerant motor stator that the present invention relates to adopts concentratred winding, spatially stator poles series connection formation one phase diametrically, independently (this independence independently comprising circuit and magnetic circuit) between phase and phase, a certain phase winding be short-circuited fault time, do not affect the normal work of other healthy phases, achieve electricity, Magnetic isolation completely.

As shown in Figure 3, drive circuit adopts independently H bridge inverter to drive, and every phase winding two ends of fault-tolerant motor are all drawn, and connect independently H bridge inverter, and takes heat isolation and physical isolation to power electronic device.The configuration achieves alternate electric isolution completely, substantially increase the ability of winding independent operating, the fault even if a certain phase or a few phase winding are short-circuited, can not be powered by corresponding bridge again, still can maintain motor rotation by healthy phases work.

When certain of motor is short-circuited fault mutually, produces larger short circuit current by this phase, cause motor unbalanced operation.Utilize equivalent torque principle, by adjusting amplitude and the phase place of other healthy phases electric currents, making the electromagnetic torque of output equivalent before and after electrical fault, realizing short circuit faults-tolerant control.

When motor normally runs, obtain according to torque formula:

$T_e=\frac{P_e}{\mathrm{\Ω}}=\frac{e_a{i}_a+e_b{i}_b+e_c{i}_c+e_d{i}_d}{\mathrm{\Ω}}---\left(1\right)$

Wherein, P _e, T _ebe respectively electromagnetic power when motor normally runs and electromagnetic torque, e _a, e _b, e _c, e _dbe respectively A, B, C, D phase winding back electromotive force, i _a, i _b, i _c, i _da, B, C, D phase institute galvanization during for normally running, Ω is the mechanical angle speed that motor exports.

The no-load back electromotive force of each phase winding is:

$\left\{\begin{array}{c}{e}_a=E_m\cos ({\mathrm{p\θ}}_r+\mathrm{\π}/2)\\ e_b=E_m\cos \left({\mathrm{p\θ}}_r\right)\\ e_c=E_m\cos ({\mathrm{p\θ}}_r-\mathrm{\π}/2)\\ e_d=E_m\cos ({\mathrm{p\θ}}_r-\mathrm{\π})\end{array}\right.---\left(2\right)$

Wherein, p is number of pole-pairs, θ _rfor rotor position angle, E _mfor no-load back electromotive force amplitude.

When motor normally works, added electric current is:

$\left\{\begin{array}{c}{i}_a=I_m\cos ({\mathrm{p\θ}}_r+\mathrm{\π}/2)\\ i_b=I_m\cos \left({\mathrm{p\θ}}_r\right)\\ i_c=I_m\cos ({\mathrm{p\θ}}_r-\mathrm{\π}/2)\\ i_d=I_m\cos ({\mathrm{p\θ}}_r-\mathrm{\π})\end{array}\right.---\left(3\right)$

Wherein, I _mfor the amplitude of electric current added when motor normally runs.

Formula (2), (3) are brought into formula (1) and are obtained formula (4):

$T_e=\frac{P_e}{\mathrm{\Ω}}=\frac{E_m{I}_m{\cos }^2({\mathrm{p\θ}}_r+\mathrm{\π}/2)+E_m{I}_m{\cos }^2\left({\mathrm{p\θ}}_r\right)}{\mathrm{\Ω}}$

$+\frac{E_m{I}_m{\cos }^2({\mathrm{p\θ}}_r-\mathrm{\π}/2)+E_m{I}_m{\cos }^2({\mathrm{p\θ}}_r-\mathrm{\π})}{\mathrm{\Ω}}---\left(4\right)$

$=\frac{{2E}_m{I}_m}{\mathrm{\Ω}}$

When A phase is short-circuited fault, obtain according to torque formula:

${T_e}^{\′}=\frac{P_e^{\′}}{\mathrm{\Ω}}=\frac{e_a{i_a}^{\′}+e_b{i}_b+e_c{i}_c+e_d{i}_d}{\mathrm{\Ω}}---\left(5\right)$

Wherein, P _e', T _e' be respectively motor A phase be short-circuited fault time electromagnetic power and electromagnetic torque, i _a' be short circuit current during A phase winding stable state.

As shown in Figure 6, short circuit current i _a'=I _am' cos (p θ _r-π) (I _am' be the amplitude of A phase winding short circuit current during stable state), carry it into formula (5):

$T_e^{\′}=\frac{P_e^{\′}}{\mathrm{\Ω}}=\frac{E_m{I_{\mathrm{am}}}^{\′}\cos ({\mathrm{p\θ}}_r+\mathrm{\π}/2)\cos ({\mathrm{p\θ}}_r-\mathrm{\π})+E_m{I}_m{\cos }^2\left({\mathrm{p\θ}}_r\right)}{\mathrm{\Ω}}$

$+\frac{E_m{I}_m{\cos }^2({\mathrm{p\θ}}_r-\mathrm{\π}/2)+E_m{I}_m{\cos }^2({\mathrm{p\θ}}_r-\mathrm{\π})}{\mathrm{\Ω}}---\left(6\right)$

$=\frac{E_m{I_{\mathrm{am}}}^{\′}\cos ({\mathrm{p\θ}}_r+\mathrm{\π}/2)\cos ({\mathrm{p\θ}}_r-\mathrm{\π})+E_m{I}_m{\cos }^2\left({\mathrm{p\θ}}_r\right)}{\mathrm{\Ω}}+\frac{E_m{I}_m}{\mathrm{\Ω}}$

E can be found out by formula (6) _mi _am' cos (p θ _r+ pi/2) cos (p θ _r-π)+E _mi _mcos ²(p θ _r) be one with rotor position angle θ _rthe amount of change, therefore, A phase be short-circuited fault time the electromagnetic torque T ' that exports _ehave very large fluctuation.

Adopt short circuit faults-tolerant control strategy, obtain according to torque formula:

${T_e}^{\′\′}=\frac{{P_e}^{\′\′}}{\mathrm{\Ω}}=\frac{e_a{i_a}^{\′}+e_b{i_b}^{\′}+e_c{e_c}^{\′}+e_d{i_d}^{\′}}{\mathrm{\Ω}}---\left(7\right)$

Wherein, P _e' ', T _eelectromagnetic power when ' ' be respectively electric motor short circuit is fault-tolerant and electromagnetic torque, i _b', i _c', i _d' be respectively the fault-tolerant electric current of short circuit of B, C, D phase winding.

Get i _c'=2i _c, i _d'=2i _d, i _b'=I _am' cos (p θ _r+ pi/2), carry it into formula (7) and obtain:

${T_e}^{\′\′}=\frac{{P_e}^{\′\′}}{\mathrm{\Ω}}=\frac{E_m{I_{\mathrm{am}}}^{\′}\cos ({\mathrm{p\θ}}_r+\mathrm{\π}/2)\cos ({\mathrm{p\θ}}_r-\mathrm{\π})+E_m{I_{\mathrm{am}}}^{\′}\cos \left({\mathrm{p\θ}}_r\right)\cos ({\mathrm{p\θ}}_r+\mathrm{\π}/2)}{\mathrm{\Ω}}$

$+\frac{{2E}_m{I}_m{\cos }^2({\mathrm{p\θ}}_r-\mathrm{\π}/2)+{2E}_m{I}_m{\cos }^2({\mathrm{p\θ}}_r-\mathrm{\π})}{\mathrm{\Ω}}$

$=\frac{{2E}_m{I}_m}{\mathrm{\Ω}}=T_e$

Hall current sensor is utilized the electric current of every phase winding to be detected, when certain phase winding electric current I > I being detected _m(I _mby amplitude alive when motor normally runs), known this is short-circuited fault mutually, digital signal processor (DSP) will perform the faults-tolerant control program write in advance, and produce corresponding control signal to the break-make of each thyristor on control H bridge inverter, produce corresponding faults-tolerant control electric current.

As shown in Figure 6, for A phase, the faults-tolerant control program write dsp chip first will write, when current sensor detects A phase current magnitude I _am> I _mtime, known A phase is short-circuited fault, and DSP will go to perform corresponding faults-tolerant control program.Namely adjust the electric current of B phase winding, make its amplitude consistent with A phase winding amplitude of short circuit, when phase place is normally run with A phase winding, current phase is consistent; Simultaneously C, D two the current amplitude of phase winding be adjusted to normal operation time 2 times of current amplitude, phase place remains unchanged.

A phase be short-circuited fault time faults-tolerant control electric current push away by following formula, obtain according to the torque principle of equal effects:

$T_e={T_e}^{\′\′}=\frac{e_a{i}_a+e_b{i}_b+e_c{i}_c+e_d{i}_d}{\mathrm{\Ω}}=\frac{e_a{i_a}^{\′}+e_b{i_b}^{\′}+e_c{i_c}^{\′}+e_d{i_d}^{\′}}{\mathrm{\Ω}}=\frac{{2E}_m{I}_m}{\mathrm{\Ω}}$

Get i _c'=2i _c, i _d'=2i _dbring above formula into:

E _mI _am′cos(pθ _r+π/2)cos(pθ _r-π)+E _mcos(pθ _r)i _b′

+2E _mI _mcos ²(pθ _r-π/2)+2E _mI _mcos ²(pθ _r-π)＝2E _mI _m

Obtain i _b'=I _am' cos (p θ _r+ pi/2)

As shown in Figure 4, be current waveform added when motor normally runs, because designed model machine has sinusoidal back electromotive force, as shown in Equation (2), therefore, permanent-magnet brushless AC motor (BrushlessAC is applicable to, BLAC) control mode, drive current as shown in Equation (3).

As shown in Figure 5, for electromagnetic torque waveform when motor normally runs, the theoretical electromagnetic torque being calculated motor output by formula (4) is about 9.46Nm, 9.34Nm is about by calculating the mean value exporting electromagnetic torque when motor normally runs to emulated data, basically identical with theoretical value.

A phase be short-circuited fault time, A phase produces short circuit current electric current as shown in Figure 6, as shown in Figure 7, the electromagnetic torque that motor exports, as shown in Figure 5, with electromagnetic torque when normally running, compare pulsation very large, now processor starts to perform faults-tolerant control program: as shown in Figure 8, and be consistent with A phase amplitude of short circuit by the range-adjusting of B phase current, phase place when phase place is normally run with A phase is consistent; As shown in Figure 9, C, D phase current is adjusted to original 2 times, and phase place remains unchanged.The electromagnetic torque waveform that fault-tolerant motor exports, as shown in Figure 10, when can find out stable state, the electromagnetic torque that motor exports is substantially identical with electromagnetic torque when normally running.

By above-mentioned formula operation and simulating, verifying, can draw a kind of short-circuit compensation control method of four-phase permanent-magnetic fault-tolerant motor, step comprises:

1) the 4 phase permanent magnet fault tolerant motor described in is divided into A, B, C, D tetra-phase, is drawn at every phase winding two ends, independently H bridge inverter in connection, and takes heat isolation and physical isolation to power electronic device, performs step 2 afterwards);

2) utilize Hall current sensor to detect the electric current of each phase winding, perform step 3) afterwards;

3) when A phase winding current amplitude I being detected _am> I _mtime, I _mby amplitude alive when motor normally runs, known A phase is short-circuited fault, performs step 4); When B phase winding current amplitude I being detected _bm> I _mtime, namely B phase winding is short-circuited fault, performs step 5); When C phase winding current amplitude I being detected _cm> I _mtime, namely C phase winding is short-circuited fault, performs step 6); When D phase winding current amplitude I being detected _dm> I _mtime, namely D phase winding is short-circuited fault, performs step 7), works as I _am≤ I _mand I _bm≤ I _mand I _cm≤ I _mand I _dm≤ I _mtime, then perform step 2);

4) on DSP CONTROL H bridge inverter, the break-make adjustment B phase winding current amplitude of each thyristor is consistent with A phase winding amplitude of short circuit, when B phase winding current phase is normally run with A phase winding, current phase is consistent, and C, D two the current amplitude of phase winding be adjusted to C, D two phase winding normally run time 2 times of current amplitude, C, D two the current phase of phase winding remain unchanged, this method terminates;

5) on DSP CONTROL H bridge inverter, the break-make adjustment C phase winding current amplitude of each thyristor is consistent with B phase winding amplitude of short circuit, when C phase winding current phase is normally run with B phase winding, current phase is consistent, and A, D two the current amplitude of phase winding be adjusted to A, D two phase winding normally run time 2 times of current amplitude, A, D two the current phase of phase winding remain unchanged, this method terminates;

6) on DSP CONTROL H bridge inverter, the break-make adjustment D phase winding current amplitude of each thyristor is consistent with C phase winding amplitude of short circuit, when D phase winding current phase is normally run with C phase winding, current phase is consistent, and A, B two the current amplitude of phase winding be adjusted to A, B two phase winding normally run time 2 times of current amplitude, A, B two the current phase of phase winding remain unchanged, this method terminates;

7) on DSP CONTROL H bridge inverter, the break-make adjustment A phase winding current amplitude of each thyristor is consistent with D phase winding amplitude of short circuit, when A phase winding current phase is normally run with D phase winding, current phase is consistent, and B, C two the current amplitude of phase winding be adjusted to B, C two phase winding normally run time 2 times of current amplitude, B, C two the current phase of phase winding remain unchanged, this method terminates.

Claims (1)

1. a short-circuit compensation control method of four-phase permanent-magnetic fault-tolerant motor, is characterized in that step comprises:

1) the 4 phase permanent magnet fault tolerant motor described in is divided into A, B, C, D tetra-phase, every phase winding two ends are drawn, independently H bridge inverter in connection, and heat isolation and physical isolation are taked to power electronic device, described power electronic device is the power device of composition four phase H bridge inverter, performs step 2 afterwards);

2) utilize Hall current sensor to detect the electric current of each phase winding, perform step 3 afterwards);

3) when A phase winding current amplitude I being detected _am> I _mtime, I _mby amplitude alive when motor normally runs, known A phase is short-circuited fault, performs step 4); When B phase winding current amplitude I being detected _bm> I _mtime, namely B phase winding is short-circuited fault, performs step 5); When C phase winding current amplitude I being detected _cm> I _mtime, namely C phase winding is short-circuited fault, performs step 6); When D phase winding current amplitude I being detected _dm> I _mtime, namely D phase winding is short-circuited fault, performs step 7), work as I _am≤ I _mand I _bm≤ I _mand I _cm≤ I _mand I _dm≤ I _mtime, then perform step 2);

4) on DSP CONTROL H bridge inverter, the break-make adjustment B phase winding current amplitude of each thyristor is consistent with A phase winding amplitude of short circuit, when B phase winding current phase is normally run with A phase winding, current phase is consistent, and C, D two the current amplitude of phase winding be adjusted to C, D two phase winding normally run time 2 times of current amplitude, C, D two the current phase of phase winding remain unchanged, this method terminates;

5) on DSP CONTROL H bridge inverter, the break-make adjustment C phase winding current amplitude of each thyristor is consistent with B phase winding amplitude of short circuit, when C phase winding current phase is normally run with B phase winding, current phase is consistent, and A, D two the current amplitude of phase winding be adjusted to A, D two phase winding normally run time 2 times of current amplitude, A, D two the current phase of phase winding remain unchanged, this method terminates;

6) on DSP CONTROL H bridge inverter, the break-make adjustment D phase winding current amplitude of each thyristor is consistent with C phase winding amplitude of short circuit, when D phase winding current phase is normally run with C phase winding, current phase is consistent, and A, B two the current amplitude of phase winding be adjusted to A, B two phase winding normally run time 2 times of current amplitude, A, B two the current phase of phase winding remain unchanged, this method terminates;

7) on DSP CONTROL H bridge inverter, the break-make adjustment A phase winding current amplitude of each thyristor is consistent with D phase winding amplitude of short circuit, when A phase winding current phase is normally run with D phase winding, current phase is consistent, and B, C two the current amplitude of phase winding be adjusted to B, C two phase winding normally run time 2 times of current amplitude, B, C two the current phase of phase winding remain unchanged, this method terminates.