CN106788083A - The location recognition method of AC permanent magnet synchronous motor rotor - Google Patents
The location recognition method of AC permanent magnet synchronous motor rotor Download PDFInfo
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- CN106788083A CN106788083A CN201611262743.1A CN201611262743A CN106788083A CN 106788083 A CN106788083 A CN 106788083A CN 201611262743 A CN201611262743 A CN 201611262743A CN 106788083 A CN106788083 A CN 106788083A
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- signal
- motor
- dac
- permanent magnet
- acceleration
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P2203/00—Indexing scheme relating to controlling arrangements characterised by the means for detecting the position of the rotor
- H02P2203/03—Determination of the rotor position, e.g. initial rotor position, during standstill or low speed operation
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P80/00—Climate change mitigation technologies for sector-wide applications
- Y02P80/10—Efficient use of energy, e.g. using compressed air or pressurized fluid as energy carrier
Abstract
The invention discloses a kind of location recognition method of AC permanent magnet synchronous motor rotor, including：Step 1：Some flux angles are chosen, stator current corresponding with the flux angle motor is encouraged into respectively in the state of open loop, and the acceleration signal of motor is recorded as excitation waveform using specific DAC signal waveforms；Step 2：Low frequency signal in removal acceleration signal；Step 3：Calculate the initial position for obtaining rotor.The present invention deactivates motor using stator current corresponding with flux angle in the state of open loop, and encourages motor by the use of specific DAC signal waveforms as excitation waveform, it is possible to reduce the displacement of motor, and then is adapted to any occasion；The present invention is very short to the time of angle detection and the identification of rotor, no more than 100ms, substantially increases operating efficiency.
Description
Technical field
The present invention relates to Power Electronic Technique and System Discrimination field, more particularly to a kind of AC permanent magnet synchronous motor rotor
Location recognition method.
Background technology
In AC servo motor, the electromagnetic torque of motor is expressed from the next：
Me=kt[iacos(θr)+ibcos(θr+2π/3)+iccos(θr-2π/3)]
Wherein：MeRepresent the electromagnetic torque that motor is produced, ia、ibAnd icThe respectively phase current of motor, ktIt is torque constant,
θrRepresent the electrical angle of rotor.
Wherein, the phase current i of motora、ibAnd icCan be expressed as follows respectively：
ia=Iqcos(θ'r)；
ib=Iqcos(θ′r+2π/3)；
ic=Iqcos(θ′r-2π/3)；
Wherein, IqIt is torque command electric current, θ 'rIt is the electrical angle of the rotor for measuring, above-mentioned phase current formula is substituted into electricity
Magnetic torque formula can be obtained：
Me=(3/2) ktIqcos(θ′r-θr)
It is assumed that θr∈[0 2π),θ'r∈ [0 2 π), it is clear that as θ 'r=θrWhen, the electromagnetic torque M of motoreObtain maximum.
When | θ 'r-θr|<During pi/2, electromagnetic torque MeFor just, when | θ 'r-θr| during=pi/2, the electromagnetic torque M of motoreIt is zero, when | θ 'r-θr
|>During pi/2, the electromagnetic torque M of motoreIt is negative, and in system closed loop a positive feedback can be caused to occur.
So, in actual servo-control system, the detection of the position of the rotor of AC permanent magnet synchronous motor is weighed very much
Will, if the position of the rotor of AC permanent magnet synchronous motor can not more accurately be detected, its consequence for producing gently then reduces motor
Output torque, motor is allowed too to generate heat, it is heavy then positive feedback can be produced, make very serious equipment damage.
The content of the invention
The present invention provides a kind of location recognition method of AC permanent magnet synchronous motor rotor, to solve to exist in the prior art
Above-mentioned technical problem.
In order to solve the above technical problems, the present invention provides a kind of location recognition method of AC permanent magnet synchronous motor rotor,
Including：Step 1：Some flux angles are chosen, stator current corresponding with the flux angle is encouraged into electricity respectively in the state of open loop
Machine, and the acceleration signal of motor is recorded as excitation waveform using specific DAC signals；Step 2：Removal acceleration signal
In low frequency signal；Step 3：Calculate the initial position for obtaining rotor.
Preferably, the forming method of the DAC signals is：Dsp controller in electric machine control system drives to motor
Device sends control signal, and the control signal is switched into analog signal using D/A converter, and the analog signal is driver
Set-point, the input of D/A converter is DAC signals.
Preferably, the waveform of the DAC signals is including the first waveform above transverse axis and below transverse axis
Second waveform, the cycle of first, second waveform is different.
Preferably, amplitude of the amplitude of the first waveform more than the second waveform.
Preferably, in the step 2, using the low frequency signal in FFT removal acceleration signal.
Preferably, the step 3 includes：Acceleration signal after removal low frequency signal is carried out to DAC signals related
Property analysis, and calculate both coefficient correlations, the initial angle of rotor is calculated according to the coefficient correlation.
Preferably, representing the acceleration signal after removal low frequency signal with acc (t), DAC signals are represented with dac (t)；
Then acceleration signal and DAC signals carry out the coefficient correlation that correlation analysis are obtained, and are represented by：
Wherein, T is the cycle of DAC signals；
Coefficient correlation b (t) is sine wave value relative to some flux angles, therefore is assumed：
B (t)=B sin (θs(t)+φ)
Wherein, B and φ are respectively the amplitude and phase of sine wave；
Some acceleration magnitudes are chosen from acceleration signal to be brought into together with the flux angle in above-mentioned two formula, calculate and obtain
The amplitude B and phase of the sine wave, phase are just the initial angle of rotor.
Preferably, the acceleration magnitude chooses 15~30, the flux angle chooses 5~8.
Preferably, the waveform of the acceleration signal is identical with the DAC signal waveforms, by right in a cycle
The DAC signals value, obtains corresponding acceleration magnitude.
Compared with prior art, the present invention has advantages below：
1st, the present invention deactivates motor using stator current corresponding with flux angle in the state of open loop, and utilizes DAC
Signal encourages motor as excitation waveform, it is possible to reduce the displacement of motor, and then is adapted to any occasion；
2nd, Identification Errors of the invention are within 8 electrical angles, and the knowledge of the initial position of existing servo motor rotor
The discrimination method of other method up to 10-15 electrical angle, therefore, the present invention relative to prior art have precision higher, keep away
Exempt from the phenomenon for motor too heating occur, and positive feedback will not be produced.
3rd, the present invention is very short to the time of angle detection and the identification of rotor, no more than 100ms, substantially increases work
Make efficiency.
Brief description of the drawings
Fig. 1 is the waveform diagram of DAC signals；
Fig. 2 is the Acceleration pulse schematic diagram of motor；
Fig. 3 is the velocity wave form schematic diagram of motor under continuous state；
Fig. 4 is the displacement waveform diagram of motor under continuous state；
Fig. 5 is the velocity wave form schematic diagram of motor under discrete state；
Fig. 6 is the displacement waveform diagram of motor under discrete state；
The motor acceleration waveform diagram that Fig. 7 causes for phase deviation；
Fig. 8 is the Acceleration pulse comparison diagram of DAC signals and motor；
Fig. 9 is the Acceleration pulse comparison diagram of motor before and after FFT；
Figure 10 is the spectrogram of FFT front motor acceleration；
Figure 11 is the spectrogram of motor acceleration after FFT.
Specific embodiment
To enable the above objects, features and advantages of the present invention more obvious understandable, below in conjunction with the accompanying drawings to the present invention
Specific embodiment be described in detail.It should be noted that, accompanying drawing of the present invention is in the form of simplification and using non-essence
Accurate ratio, is only used to conveniently, lucidly aid in illustrating the purpose of the embodiment of the present invention.
The location recognition method of AC permanent magnet synchronous motor rotor of the invention, including：
Step 1：5~8 flux angles are chosen, preferably 6 flux angles of the invention will stator corresponding with 6 flux angles
Electric current encourages motor respectively in the state of open loop, records the acceleration signal of motor.
Specifically, using DAC signals as excitation waveform, the forming method of the DAC signals is the present invention：Motor control
DSP (data-signal treatment) controllers in system send control signal DAC to motor driver, and control signal DAC is one
The input of individual data signal and the D/A converter being connected on motor driver, D/A converter is by the control signal
DAC switchs to analog signal, and the analog signal is the set-point of driver, and the input of D/A converter is DAC signals.Need
Illustrate, because the input of D/A converter is corresponded with the output of D/A converter, so, DAC signals are motor drive
The set-point of dynamic device.Using the DAC signals as excitation waveform, the displacement of motor on the one hand can be reduced；On the other hand
The resonant frequency of motor can also be avoided being close to, in order to avoid test result is had a negative impact.
The waveform of the DAC signals is as shown in figure 1, including the first waveform above transverse axis and below transverse axis
Second waveform, the cycle T of the first waveform1With the cycle T of the second waveform2Difference, in the present embodiment, T1=5ms, T2=
10ms.Further, in the case of continuous, motor, movement of the motor in an Energizing cycle are encouraged with the DAC signals
Distance is 0.As shown in Figures 2 to 4, the respectively waveform of the acceleration of motor, speed and displacement；Wherein, the acceleration of motor
Waveform is similar with the waveform of DAC.
Further, amplitude of the amplitude of first waveform more than the second waveform.Specifically, under discrete state, Fig. 5 and Tu
6 speed and the excitation waveform of displacement waveform, i.e., for being respectively motor under discrete state terminate the absolute displacement of rear motor
It is not 0, therefore, in the present embodiment, the width of the second waveform amplitude of the first waveform above transverse axis being set to below transverse axis
1.0256 times of value, so may insure that absolute displacement of the motor at the end of an Energizing cycle is 0.
Step 2：Using FFT removal acceleration signal in low frequency signal, wherein, the low frequency signal by
The phase deviation of motor causes.Specifically, in the case where design of electrical motor and adjustment are good, motor has a small phase deviation,
When control system closed loop, the phase deviation will not allow motor vibrating.But if motor is not adjusted to good enough,
Motor has a larger phase deviation, and when control system closed loop, the phase deviation can allow motor to produce one and big tremble
It is dynamic, and then a negative impact can be produced to the detection of the initial position of rotor.The motor caused by phase deviation plus
As shown in fig. 7, wherein, the motor corresponding umber of pulse that rotates a circle is 2000000 to velocity wave form.When pumping signal is added on motor
When, the Acceleration pulse and DAC signal waveforms of motor, as shown in Figure 8.Further, the low frequency signal can be by quick Fu
Vertical leaf transformation (FFT) is removed.From above describing, the frequency of first, second waveform is respectively 200Hz (1/T1) and 100Hz
(1/T2), therefore, the low frequency signal of below 60Hz all this be removed, the Acceleration pulse before and after FFT is as shown in Figure 9.Plus
Histogram of the rate signal before and after FFT is as shown in Figure 10 and Figure 11.Further, parameter selection in FFT
For：Sample frequency is 2000Hz, and the points in FFT are 256, and the frequency interval between two consecutive points is 2000/256=
7.8125Hz。
Step 3：Calculate the initial position for obtaining rotor.To the acceleration signal after removal low frequency signal and DAC letters
Number correlation analysis are carried out, and calculate both coefficient correlations, the initial angle of rotor is calculated according to the coefficient correlation
Degree.
Specifically, step 3 includes：
Step 31：Correlation analysis are carried out to the acceleration signal and DAC signals after removal low frequency signal, and calculates two
Person's coefficient correlation.
Specifically, represented by the motor acceleration signal after FFT treatment with acc (t), DAC is represented with dac (t)
Signal.Acceleration signal to DAC signals and motor makees a correlation analysis, and coefficient correlation is calculated in an Energizing cycle：
Wherein T is the cycle of DAC signals, and the value of b (t) is for six flux angles, it should into sine wave value, false
It is fixed
B (t)=B sin (θs(t)+φ) (2)
Wherein B and φ are respectively the amplitude and phase of sine wave.
Step 32：Some acceleration magnitudes are chosen from acceleration signal to be brought into together with the flux angle in above-mentioned two formula,
The amplitude B and phase for obtaining the sine wave are calculated, phase is just the initial angle of rotor.
Specially：The waveform of the acceleration signal is identical with the DAC signal waveforms, by a cycle to institute
DAC signal values are stated, corresponding acceleration magnitude is obtained, 15~30 are generally taken, the present embodiment is in a complete Energizing cycle
DAC signals in take 20 values, then the acceleration of motor also has 20 values in a complete Energizing cycle, to formula (1)
Discretization is just changed into：
In the present embodiment, six flux angles difference values are pi/2,5 π/6,7 π/6,3 pi/2s, 11 π/6 and 13 π/6, by this six
Individual angle is designated as θs(i), i=1,2 ... 6, then have：
Simultaneously
So
Wherein, phase is just the initial angle of the permanent-magnetic synchronous motor rotor for recognizing.
Below as a example by rotating (DDR) motor, technique effect of the invention is illustrated：
Wherein, the amplitude of DAC signals is 500LSB, motor rotate a circle encoder output umber of pulse for 2000000, with
With pi/2,5 π/6,7 π/6,3 pi/2s, 11 π/6 and the corresponding stator current of 13 π/6 six flux angle encourage motor, excitation waveform to adopt
DAC signals are used, as shown in Figure 1.
Be calculated the acceleration signal of motor, in each Energizing cycle, 20 values selected from DAC signals, then it is right
The acceleration signal answered has 20 values, and b (i) (i=1,2 ... value 6), i.e. each flux angle correspondence can be obtained using formula (3)
One b (i), as shown in table 1.
The flux angle of the motor of table 1. and the value of b (i)
| θs(i) | b(i) | |
| 1 | π/2 | 31061.1 |
| 2 | 5π/6 | 99409.5 |
| 3 | 7π/6 | 95916.1 |
| 4 | 3π/2 | -2473.3 |
| 5 | 11π/6 | -99034.8 |
| 6 | 13π/6 | -97396.6 |
Can be obtained by formula (4) and formula (5)
a1=201522.2, a2=-275471
Can be obtained by formula (6) and formula (7)
Then the initial electrical angle of the rotor of the DDR motors is φ=- 0.939206.
So having
B (i)=B sin (θs(i)+φ)=113771.6sin (θs(i) -0.939206) i=1,2 ... 6
Filtering error is：
It follows that detection time of the invention is short, calculate quick and convenient, and with precision higher.
Obviously, those skilled in the art can carry out various changes and modification without deviating from spirit of the invention to invention
And scope.So, if these modifications of the invention and modification belong to the claims in the present invention and its equivalent technologies scope it
Interior, then the present invention is also intended to including including these changes and modification.
Claims (9)
1. a kind of location recognition method of AC permanent magnet synchronous motor rotor, it is characterised in that including：
Step 1：Some flux angles are chosen, stator current corresponding with the flux angle is encouraged into electricity respectively in the state of open loop
Machine, and the acceleration signal of motor is recorded as excitation waveform using DAC signals；
Step 2：Low frequency signal in removal acceleration signal；
Step 3：Calculate the initial position for obtaining rotor.
2. the location recognition method of AC permanent magnet synchronous motor rotor as claimed in claim 1, it is characterised in that the DAC
The forming method of signal is：Dsp controller in electric machine control system sends control signal to motor driver, is turned using D/A
The control signal is switched to analog signal by parallel operation, and the analog signal is the set-point of driver, and the input of D/A converter is
It is DAC signals.
3. the location recognition method of AC permanent magnet synchronous motor rotor as claimed in claim 1, it is characterised in that the DAC
The waveform of signal includes the first waveform above transverse axis and the second waveform below transverse axis, first, second ripple
The cycle of shape is different.
4. the location recognition method of AC permanent magnet synchronous motor rotor as claimed in claim 3, it is characterised in that described first
Amplitude of the amplitude of waveform more than the second waveform.
5. the location recognition method of AC permanent magnet synchronous motor rotor as claimed in claim 1, it is characterised in that the step
In 2, using the low frequency signal in FFT removal acceleration signal.
6. the location recognition method of AC permanent magnet synchronous motor rotor as claimed in claim 1, it is characterised in that the step
3 include：Correlation analysis are carried out to the acceleration signal and DAC signals after removal low frequency signal, and calculates both phase relations
Number, the initial angle of rotor is calculated according to the coefficient correlation.
7. the location recognition method of AC permanent magnet synchronous motor rotor as claimed in claim 6, it is characterised in that
The acceleration signal after removal low frequency signal is represented with acc (t), DAC signals are represented with dac (t)；
Then acceleration signal and DAC signals carry out the coefficient correlation that correlation analysis are obtained, and are represented by：
Wherein, T is the cycle of DAC signals；
Coefficient correlation b (t) is sine wave value relative to some flux angles, therefore is assumed：
B (t)=B sin (θs(t)+φ)
Wherein, B and φ are respectively the amplitude and phase of sine wave；
Some acceleration magnitudes are chosen from acceleration signal to be brought into together with the flux angle in above-mentioned two formula, calculate and obtain described
The amplitude B and phase of sine wave, phase are just the initial angle of rotor.
8. the location recognition method of AC permanent magnet synchronous motor rotor as claimed in claim 7, it is characterised in that the acceleration
Angle value chooses 15~30, and the flux angle chooses 5~8.
9. the location recognition method of AC permanent magnet synchronous motor rotor as claimed in claim 8, it is characterised in that the acceleration
The waveform for spending signal is identical with the DAC signal waveforms, and, to the DAC signals value, correspondence is obtained by a cycle
Acceleration magnitude.
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| CN201611262743.1A CN106788083B (en) | 2016-12-30 | 2016-12-30 | The location recognition method of AC permanent magnet synchronous motor rotor |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107196572A (en) * | 2017-07-25 | 2017-09-22 | 温州大学 | One kind is based on permanent-magnetic synchronous motor rotor initial position detection device and method |
| WO2022247328A1 (en) * | 2021-05-28 | 2022-12-01 | 青岛海尔生物医疗科技有限公司 | Centrifuge rotor identification method and system |
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| US20100264861A1 (en) * | 2009-04-21 | 2010-10-21 | Schneider Toshiba Inverter Europe Sas | Method for determining the position of the flux vector of a motor |
| CN103401502A (en) * | 2013-07-22 | 2013-11-20 | 深圳市汇川技术股份有限公司 | System and method for identifying initial angle of permanent magnet synchronous motor |
| CN103684184A (en) * | 2013-11-21 | 2014-03-26 | 清华大学 | Linear motor initial phase determination method |
| CN104158462A (en) * | 2014-09-01 | 2014-11-19 | 石成富 | Method for detecting initial position of sensorless permanent magnet synchronous motor |
| CN106100488A (en) * | 2016-08-16 | 2016-11-09 | 上海金脉电子科技有限公司 | Low-power permagnetic synchronous motor non-position sensor vector control method |
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2016
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100264861A1 (en) * | 2009-04-21 | 2010-10-21 | Schneider Toshiba Inverter Europe Sas | Method for determining the position of the flux vector of a motor |
| CN103401502A (en) * | 2013-07-22 | 2013-11-20 | 深圳市汇川技术股份有限公司 | System and method for identifying initial angle of permanent magnet synchronous motor |
| CN103684184A (en) * | 2013-11-21 | 2014-03-26 | 清华大学 | Linear motor initial phase determination method |
| CN104158462A (en) * | 2014-09-01 | 2014-11-19 | 石成富 | Method for detecting initial position of sensorless permanent magnet synchronous motor |
| CN106100488A (en) * | 2016-08-16 | 2016-11-09 | 上海金脉电子科技有限公司 | Low-power permagnetic synchronous motor non-position sensor vector control method |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107196572A (en) * | 2017-07-25 | 2017-09-22 | 温州大学 | One kind is based on permanent-magnetic synchronous motor rotor initial position detection device and method |
| CN107196572B (en) * | 2017-07-25 | 2019-06-11 | 温州大学 | One kind being based on permanent-magnetic synchronous motor rotor initial position detection device and method |
| WO2022247328A1 (en) * | 2021-05-28 | 2022-12-01 | 青岛海尔生物医疗科技有限公司 | Centrifuge rotor identification method and system |
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