CN106788033A - Field weakening control method, the device of list PI electric current loops during ovennodulation - Google Patents
Field weakening control method, the device of list PI electric current loops during ovennodulation Download PDFInfo
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- CN106788033A CN106788033A CN201611249812.5A CN201611249812A CN106788033A CN 106788033 A CN106788033 A CN 106788033A CN 201611249812 A CN201611249812 A CN 201611249812A CN 106788033 A CN106788033 A CN 106788033A
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- synchronous motor
- ovennodulation
- permagnetic synchronous
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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
- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/0003—Control strategies in general, e.g. linear type, e.g. P, PI, PID, using robust control
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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
- H02P27/00—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage
- H02P27/04—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage
- H02P27/06—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters
- H02P27/08—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters with pulse width modulation
- H02P27/12—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters with pulse width modulation pulsing by guiding the flux vector, current vector or voltage vector on a circle or a closed curve, e.g. for direct torque control
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- Power Engineering (AREA)
- Control Of Ac Motors In General (AREA)
Abstract
The invention discloses the control system of the field weakening control method, device and permagnetic synchronous motor of list PI electric current loops during a kind of permagnetic synchronous motor ovennodulation, wherein, method includes:Obtaining the ovennodulation COEFFICIENT K H of permagnetic synchronous motor, and calculate permagnetic synchronous motor carries out the action time T1 and T2 of two in six basic effectively vectors when SVPWM is controlled;Judge whether that control permagnetic synchronous motor enters ovennodulation and list PI electric current loop weak magnetic control patterns according to ovennodulation COEFFICIENT K H, T1 and T2;If, then given the output of speed ring as D shaft currents, and it is given according to D shaft currents and D axles feedback current carries out the regulation of D axle PI electric current loops to obtain D shaft voltages, and weak magnetic control is carried out to permagnetic synchronous motor into the Q shaft voltages before ovennodulation and list PI electric current loop weak magnetic control patterns according to D shaft voltages and permagnetic synchronous motor, thereby, it is possible to ensure stable operation when permagnetic synchronous motor ovennodulation and weak magnetic.
Description
Technical field
The present invention relates to list PI electric current loops during a kind of permagnetic synchronous motor field, more particularly to permagnetic synchronous motor ovennodulation
Field weakening control method, a kind of permagnetic synchronous motor ovennodulation when list PI electric current loops weak magnetic control device and a kind of permanent-magnet synchronous
The control system of motor.
Background technology
Classics are needed in PMSM (permanent magnet synchronous motor, permagnetic synchronous motor) controls
The speed ring of three close-loop control, i.e., one, D shaft currents ring, Q shaft current rings, as shown in Figure 1.
The voltage equation of permagnetic synchronous motor D, Q axle is:
Electromagnetic torque is:
Wherein, TeIt is the electromagnetic torque of permagnetic synchronous motor, PnIt is the number of pole-pairs of permagnetic synchronous motor,It is permanent magnet magnetic
Chain, IqIt is Q shaft currents, Id is D shaft currents, and Lq, Ld are respectively D, Q axle inductance.R is phase resistance, and p is differential operator, and ω is electricity
Angular speed, Ud and Uq are respectively D shaft voltages and Q shaft voltages.
In weak magnetic, directly above-mentioned voltage equation is processed, remove micro component, obtained:
Because D, Q axle are mutually coupled, so D, Q shaft current can not be obtained individually by corresponding electric current loop.And
When depth weak magnetic and ovennodulation combination, the problems such as may result in high frequency operation step-out, produce high current, permanent magnetism is had a strong impact on same
Walk the stable operation of motor.
The content of the invention
It is contemplated that at least solving one of technical problem in above-mentioned technology to a certain extent.
Therefore, the weak magnetic it is an object of the present invention to propose list PI electric current loops during a kind of permagnetic synchronous motor ovennodulation
Control method, the method can make permagnetic synchronous motor stable operation in ovennodulation and weak magnetic, and can effectively solve the problem that D, Q axle
The problem being mutually coupled, simplifies PMSM control systems.
Second object of the present invention is a kind of weak magnetic control of list PI electric current loops when proposing permagnetic synchronous motor ovennodulation
Device processed.
Third object of the present invention is to propose a kind of control system of permagnetic synchronous motor.
To reach above-mentioned purpose, the list when embodiment of first aspect present invention proposes a kind of permagnetic synchronous motor ovennodulation
The field weakening control method of PI electric current loops, comprises the following steps:The ovennodulation COEFFICIENT K H of the permagnetic synchronous motor is obtained, and is calculated
When the permagnetic synchronous motor carries out two basic effectively effects of vector in six basic effectively vectors when SVPWM is controlled
Between T1 and T2;Action time T1 and T2 according to the ovennodulation COEFFICIENT K H, described two basic effectively vectors judge whether control
Make the permagnetic synchronous motor into ovennodulation and list PI electric current loop weak magnetic control patterns;When the permagnetic synchronous motor enters institute
When stating ovennodulation with list PI electric current loop weak magnetic control patterns, given the output of speed ring as D shaft currents, and according to the D
Given and the permagnetic synchronous motor the D axles feedback current of shaft current carries out D axle PI electric current loops and adjusts to obtain D shaft voltages, with
And before according to the D shaft voltages and the permagnetic synchronous motor entering the ovennodulation and list PI electric current loop weak magnetic control patterns
Q shaft voltages weak magnetic control is carried out to the permagnetic synchronous motor.
The field weakening control method of list PI electric current loops during the permagnetic synchronous motor ovennodulation of the embodiment of the present invention, according to ovennodulation
Coefficient, the action time control permagnetic synchronous motor of two basic effectively vectors enter ovennodulation and are controlled with list PI electric current loops weak magnetic
Pattern, gives the output of speed ring as D shaft currents, and the D axles of and permagnetic synchronous motor given according to D shaft currents feed back electricity
Stream carries out the regulation of D axle PI electric current loops to obtain D shaft voltages, so according to D shaft voltages and permagnetic synchronous motor enter ovennodulation with
Q shaft voltages before single PI electric current loops weak magnetic control pattern carry out weak magnetic control to permagnetic synchronous motor.Thereby, it is possible to make permanent magnetism same
Step motor stable operation in ovennodulation and weak magnetic, and the problem that D, Q axle are mutually coupled is can effectively solve the problem that, simplify PMSM controls
System.
In addition, during permagnetic synchronous motor ovennodulation according to the above embodiment of the present invention list PI electric current loops weak magnetic controlling party
Method can also have following additional technical characteristic:
According to one embodiment of present invention, according to the ovennodulation COEFFICIENT K H, the work of described two basic effectively vectors
Judged whether to control the permagnetic synchronous motor to enter ovennodulation and list PI electric current loop weak magnetic control patterns, bag with time T1 and T2
Include:T1 and T2 sums are calculated, and the T1 and T2 sums are carried out low-pass filtering treatment to obtain start-up time Ton;Judge institute
Whether start-up time Ton and six Dead Time Tdead sums are stated more than the ovennodulation COEFFICIENT K H;If the start-up time
Ton and six Dead Time Tdead sum is more than the ovennodulation COEFFICIENT K H, then control the permagnetic synchronous motor to enter described
Ovennodulation and list PI electric current loop weak magnetic control patterns.
According to one embodiment of present invention, the ovennodulation COEFFICIENT K H meets relational expression:1 > KH > 0.8666.
According to one embodiment of present invention, the busbar voltage calculating permanent magnetism also by the permagnetic synchronous motor is same
The voltage between terminals maximum Vsmax of motor is walked, and according to the voltage between terminals maximum Vsmax and the ovennodulation coefficient
KH is limited the permagnetic synchronous motor into the ovennodulation with the Q shaft voltages before list PI electric current loop weak magnetic control patterns
System treatment.
According to one embodiment of present invention, it is weak with list PI electric current loops into the ovennodulation in the permagnetic synchronous motor
After magnetic control pattern, also include:According to the voltage between terminals maximum Vsmax and ovennodulation COEFFICIENT K H and described
The D axle inductances of permagnetic synchronous motor, the angular rate of the permagnetic synchronous motor, the permanent magnet flux linkage of the permagnetic synchronous motor
Calculate that the permagnetic synchronous motor exits the ovennodulation and list PI electric current loop weak magnetic control patterns cuts out electric current ICut out;Judge
Whether the D shaft currents are given cuts out electric current I more than describedCut out;If the D shaft currents are given to cut out electric current more than described
ICut out, then the permagnetic synchronous motor is controlled to exit the ovennodulation and list PI electric current loop weak magnetic control patterns.
To reach above-mentioned purpose, list PI when second aspect present invention embodiment proposes a kind of permagnetic synchronous motor ovennodulation
The weak magnetic control device of electric current loop, including:Acquisition module, the ovennodulation COEFFICIENT K H for obtaining the permagnetic synchronous motor;Meter
Module is calculated, it is basic for calculating two that the permagnetic synchronous motor carried out in six basic effectively vectors when SVPWM is controlled
The action time T1 and T2 of effective vector;Judge module, for according to the ovennodulation COEFFICIENT K H, described two basic effectively arrows
The action time T1 and T2 of amount judge whether that control the permagnetic synchronous motor to enter ovennodulation controls with list PI electric current loops weak magnetic
Pattern;Weak magnetic control module, mould is controlled for entering the ovennodulation in the permagnetic synchronous motor with list PI electric current loops weak magnetic
Given the output of speed ring as D shaft currents during formula, and according to the given D with the permagnetic synchronous motor of the D shaft currents
Axle feedback current carries out the regulation of D axle PI electric current loops to obtain D shaft voltages, and according to the D shaft voltages and the permanent-magnet synchronous
Motor is carried out with the Q shaft voltages before list PI electric current loop weak magnetic control patterns into the ovennodulation to the permagnetic synchronous motor
Weak magnetic is controlled.
The weak magnetic control device of list PI electric current loops during the permagnetic synchronous motor ovennodulation of the embodiment of the present invention, by judging mould
Root tuber judges whether permagnetic synchronous motor enters ovennodulation and list according to the action time of ovennodulation coefficient, two basic effectively vectors
PI electric current loop weak magnetic control patterns, when permagnetic synchronous motor enters ovennodulation with list PI electric current loop weak magnetic control patterns, pass through
Weak magnetic control module gives the output of speed ring as D shaft currents, and according to the given D with permagnetic synchronous motor of D shaft currents
Axle feedback current carries out the regulation of D axle PI electric current loops to obtain D shaft voltages, and then is entered according to D shaft voltages and permagnetic synchronous motor
Ovennodulation carries out weak magnetic control with the Q shaft voltages before list PI electric current loop weak magnetic control patterns to permagnetic synchronous motor.Thus, energy
Enough make permagnetic synchronous motor stable operation in ovennodulation and weak magnetic, and can effectively solve the problem that the problem that D, Q axle are mutually coupled, letter
Change PMSM control systems.
In addition, the weak magnetic control of list PI electric current loops is filled during permagnetic synchronous motor ovennodulation according to the above embodiment of the present invention
Putting can also have following additional technical characteristic:
According to one embodiment of present invention, the computing module is additionally operable to calculate T1 and T2 sums, and by low pass filtered
Ripple device carries out low-pass filtering treatment to obtain start-up time Ton to the T1 and T2 sums, and the judge module is further used for
Whether the start-up time Ton and six Dead Time Tdead sums are judged more than the ovennodulation COEFFICIENT K H, wherein, in institute
When stating start-up time Ton and six Dead Time Tdead sums more than the ovennodulation COEFFICIENT K H, the weak magnetic control module control
Make the permagnetic synchronous motor into the ovennodulation and list PI electric current loop weak magnetic control patterns.
According to one embodiment of present invention, the ovennodulation COEFFICIENT K H meets relational expression:1 > KH > 0.8666.
According to one embodiment of present invention, described device, also includes:Q shaft voltages limit module, the Q shaft voltages limit
Molding block calculates the voltage between terminals maximum of the permagnetic synchronous motor by the busbar voltage of the permagnetic synchronous motor
Vsmax, and the permagnetic synchronous motor is entered according to the voltage between terminals maximum Vsmax and the ovennodulation COEFFICIENT K H
The ovennodulation carries out limitation treatment with the Q shaft voltages before list PI electric current loop weak magnetic control patterns.
According to one embodiment of present invention, it is weak with list PI electric current loops into the ovennodulation in the permagnetic synchronous motor
After magnetic control pattern, the computing module is always according to the voltage between terminals maximum Vsmax and ovennodulation COEFFICIENT K H
And D axle inductances, the angular rate of the permagnetic synchronous motor, the permagnetic synchronous motor of the permagnetic synchronous motor are forever
What permagnetic synchronous motor described in magnet flux linkage calculation exited the ovennodulation and list PI electric current loop weak magnetic control patterns cuts out electric current
ICut out, whether the judge module is additionally operable to judge that the D shaft currents are given and cuts out electric current I more than describedCut out, wherein, in the D
Shaft current is given to cut out electric current I more than describedCut outWhen, it is described that the weak magnetic control module controls the permagnetic synchronous motor to exit
Ovennodulation and list PI electric current loop weak magnetic control patterns.
Further, the present invention proposes a kind of control system of permagnetic synchronous motor, and it includes above-mentioned implementation of the invention
The weak magnetic control device of list PI electric current loops during the permagnetic synchronous motor ovennodulation of example.
The control system of the permagnetic synchronous motor of the embodiment of the present invention, list during by above-mentioned permagnetic synchronous motor ovennodulation
The weak magnetic control device of PI electric current loops, can not only make permagnetic synchronous motor stable operation in ovennodulation and weak magnetic, additionally it is possible to
Effectively solve the problems, such as that D, Q axle are mutually coupled, and simple structure.
Brief description of the drawings
Fig. 1 is the structural representation of three rings (speed ring, D shaft currents ring, Q shaft currents ring) control in permagnetic synchronous motor control
Figure;
The weak magnetic controlling party of list PI electric current loops when Fig. 2 is permagnetic synchronous motor ovennodulation according to an embodiment of the invention
The flow chart of method.
Fig. 3 is six basic effectively vectors that permagnetic synchronous motor according to embodiments of the present invention carries out when SVPWM is controlled
Schematic diagram;
The structure of the weak magnetic control of list PI electric current loops when Fig. 4 is permagnetic synchronous motor ovennodulation according to embodiments of the present invention
Schematic diagram;
The weak magnetic control dress of list PI electric current loops when Fig. 5 is permagnetic synchronous motor ovennodulation according to an embodiment of the invention
The structured flowchart put;
The weak magnetic control of list PI electric current loops when Fig. 6 is permagnetic synchronous motor ovennodulation in accordance with another embodiment of the present invention
The structured flowchart of device.
Specific embodiment
Embodiments of the invention are described below in detail, the example of the embodiment is shown in the drawings, wherein from start to finish
Same or similar label represents same or similar element or the element with same or like function.Below with reference to attached
It is exemplary to scheme the embodiment of description, it is intended to for explaining the present invention, and be not considered as limiting the invention.
Below with reference to the accompanying drawings the weak magnetic control of list PI electric current loops during the permagnetic synchronous motor ovennodulation of the embodiment of the present invention is described
The control system of method processed, device and permagnetic synchronous motor.
The weak magnetic controlling party of list PI electric current loops when Fig. 2 is according to one embodiment of the invention permagnetic synchronous motor ovennodulation
Method.As shown in Fig. 2 the control method is comprised the following steps:
S1, obtain permagnetic synchronous motor ovennodulation COEFFICIENT K H, and calculate permagnetic synchronous motor carry out SVPWM control when
Two the action time T1 and T2 of basic effectively vector in six basic effectively vectors.
Wherein, ovennodulation COEFFICIENT K H meets relational expression:1 > KH > 0.8666.
Specifically, as shown in figure 3, U0, U60, U120, U180, U240, U300 carry out SVPWM controls for permagnetic synchronous motor
Six basic effectively vectors when processed, and constitute six sectors.
For example, when output voltage Uout falls in the sector of U0, U60 composition, there is following formula (1):
Wherein, T1 and T2 are respectively the action time of basic effectively vector U0, U60 in a carrier cycle T, and T0 is zero
The action time of vector.
Being projected as under α, β rest frame:
Action time is normalized, even T=1, is then had:
It should be noted that the computational methods of any two adjacent basic effectively the action time T1 and T2 of vector are to ability
It is known for the technical staff in domain, will not be described here.
S2, action time T1 and T2 according to ovennodulation COEFFICIENT K H, two basic effectively vectors judge whether to control permanent magnetism
Synchronous motor enters ovennodulation and list PI electric current loop weak magnetic control patterns.
Specifically, T1 and T2 sums are calculated, and T1 and T2 sums is carried out low-pass filtering treatment to obtain start-up time
Ton;Judge start-up time Ton and six Dead Time Tdead sums whether more than ovennodulation COEFFICIENT K H;If start-up time
Ton and six Dead Time Tdead sum is more than ovennodulation COEFFICIENT K H, then control permagnetic synchronous motor to enter ovennodulation and list PI
Electric current loop weak magnetic control pattern.
It should be noted that because the value of T1+T2 is always in fluctuation, therefore T1 and T2 sums can be carried out at LPF
Reason, and then obtain start-up time Ton=Lowpass (T1+T2).
S3, when permagnetic synchronous motor enters ovennodulation with list PI electric current loop weak magnetic control patterns, by the output of speed ring
It is given as D shaft currents, and the D axles feedback current of and permagnetic synchronous motor given according to D shaft currents carries out D axle PI electric current loops tune
Save to obtain D shaft voltages, and ovennodulation is entered according to D shaft voltages and permagnetic synchronous motor and control mould with list PI electric current loops weak magnetic
Q shaft voltages before formula carry out weak magnetic control to permagnetic synchronous motor.
Specifically, as shown in figure 4, when permagnetic synchronous motor enters ovennodulation with list PI electric current loop weak magnetic control patterns, inciting somebody to action
The output of speed ring gives Idref as D shaft currents, and anti-according to the D axles of the given Idref of D shaft currents and permagnetic synchronous motor
Supply current Id_fbk carries out the regulation of D axle PI electric current loops to obtain D shaft voltage Ud, and according to D shaft voltages Ud and permanent magnet synchronous electric
Machine carries out weak magnetic control into the Q shaft voltages Uq before ovennodulation and list PI electric current loop weak magnetic control patterns to permagnetic synchronous motor
System.Thereby, it is possible to realize stable operation when permagnetic synchronous motor ovennodulation and weak magnetic.
Q shaft voltages prescribed skew is excessive when in one embodiment of the invention, in order to prevent busbar voltage from changing, and also leads to
The busbar voltage for crossing permagnetic synchronous motor calculates the voltage between terminals maximum Vsmax of permagnetic synchronous motor, and according between terminal
Voltage max Vsmax and ovennodulation COEFFICIENT K H enters ovennodulation and list PI electric current loop weak magnetic control patterns to permagnetic synchronous motor
Q shaft voltages before carry out limitation treatment.
Specifically, Vsmax can be calculated by formula (4), and then according to voltage between terminals maximum Vsmax and ovennodulation coefficient
KH is carried out at limitation to permagnetic synchronous motor into the Q shaft voltages Uq before ovennodulation and list PI electric current loop weak magnetic control patterns
Reason, can be Uq≤Vsmax*KH/0.866.
Wherein, Udc is busbar voltage, and Vsmax is voltage between terminals maximum.
Further, after permagnetic synchronous motor enters ovennodulation and list PI electric current loop weak magnetic control patterns, according to end
The D axle inductances of voltage max Vsmax and ovennodulation COEFFICIENT K H and permagnetic synchronous motor, the electric angle of permagnetic synchronous motor between son
Speed, the permanent magnet flux linkage of permagnetic synchronous motor calculate permagnetic synchronous motor and exit ovennodulation with list PI electric current loops weak magnetic control mould
Formula cuts out electric current ICut out;Judge that whether D shaft currents give to be more than and cut out electric current ICut out;If D shaft currents give to be more than cuts out electricity
Stream ICut out, then permagnetic synchronous motor is controlled to exit ovennodulation and list PI electric current loop weak magnetic control patterns.
Specifically, can be calculated by following formula (5) and cut out electric current ICut out:
Wherein, Ld is the D axle inductances of permagnetic synchronous motor, and w is the angular rate of permagnetic synchronous motor,It is permanent-magnet synchronous
The permanent magnet flux linkage of motor.
It should be noted that working as Idref<When 0, it is believed that be weak magnetic, voltage vector weakens;Work as Idref>When 0, it is believed that be to increase
Magnetic, voltage vector enhancing.
To sum up, during the permagnetic synchronous motor ovennodulation of the embodiment of the present invention list PI electric current loops field weakening control method, according to
Ovennodulation coefficient, the action time of two basic effectively vectors control permagnetic synchronous motor weak with list PI electric current loops into ovennodulation
Magnetic control pattern, gives the output of speed ring as D shaft currents, and according to the given D axles with permagnetic synchronous motor of D shaft currents
Feedback current carries out the regulation of D axle PI electric current loops to obtain D shaft voltages, and then is entered according to D shaft voltages and permagnetic synchronous motor
Modulation carries out weak magnetic control with the Q shaft voltages before list PI electric current loop weak magnetic control patterns to permagnetic synchronous motor, and passes through
The busbar voltage of permagnetic synchronous motor calculates the voltage between terminals maximum of permagnetic synchronous motor, and enters in permagnetic synchronous motor
It is same according to voltage between terminals maximum and ovennodulation coefficient and permanent magnetism after ovennodulation and list PI electric current loop weak magnetic control patterns
Walk D axle inductances, the angular rate of permagnetic synchronous motor, the permanent magnet flux linkage calculating permanent magnet synchronous electric of permagnetic synchronous motor of motor
Machine exits the electric current that cuts out of ovennodulation and list PI electric current loop weak magnetic control patterns, and is given according to D shaft currents and cut out electric current control
Permagnetic synchronous motor processed exits ovennodulation and list PI electric current loop weak magnetic control patterns.Thereby, it is possible to make permagnetic synchronous motor in mistake
Stable operation when modulation and weak magnetic, and the problem that D, Q axle are mutually coupled is can effectively solve the problem that, simplify PMSM control systems.
The weak magnetic control dress of list PI electric current loops when Fig. 5 is permagnetic synchronous motor ovennodulation according to an embodiment of the invention
The structured flowchart put.As shown in figure 5, the device includes:The control of acquisition module 10, computing module 20, judge module 30 and weak magnetic
Module 40.
Wherein, acquisition module 10 is used to obtain the ovennodulation COEFFICIENT K H of permagnetic synchronous motor.Computing module 20 is used to calculate
Permagnetic synchronous motor carries out two action time T1 of basic effectively vector in six basic effectively vectors when SVPWM is controlled
And T2.Judge module 30 is used to be judged whether according to the action time T1 and T2 of ovennodulation COEFFICIENT K H, two basic effectively vectors
Control permagnetic synchronous motor enters ovennodulation and list PI electric current loop weak magnetic control patterns.Weak magnetic control module 40 is used for same in permanent magnetism
Step motor gives when entering ovennodulation with list PI electric current loop weak magnetic control patterns using the output of speed ring as D shaft currents, and root
According to D shaft currents, the D axles feedback current of given and permagnetic synchronous motor carries out the regulation of D axle PI electric current loops to obtain D shaft voltages, and
According to D shaft voltages and permagnetic synchronous motor into the Q shaft voltages before ovennodulation and list PI electric current loop weak magnetic control patterns to forever
Magnetic-synchro motor carries out weak magnetic control.
Wherein, ovennodulation COEFFICIENT K H meets relational expression:1 > KH > 0.8666.
Specifically, as shown in figure 3, U0, U60, U120, U180, U240, U300 carry out SVPWM controls for permagnetic synchronous motor
Six basic effectively vectors when processed, and constitute six sectors.
For example, when output voltage Uout falls in the sector of U0, U60 composition, there is formula (1):
Wherein, T1 and T2 are respectively the action time of basic effectively vector U0, U60 in a carrier cycle T, and T0 is zero
The action time of vector.
Being projected as under α, β rest frame:
Action time is normalized, even T=1, is then had:
It should be noted that the computational methods of any two adjacent basic effectively the action time T1 and T2 of vector are to ability
It is known for the technical staff in domain, will not be described here.
In one embodiment of the invention, computing module 20 is additionally operable to calculate T1 and T2 sums, and by LPF
Device carries out low-pass filtering treatment to obtain start-up time Ton to T1 and T2 sums.
Further, judge module 30 is used to judge whether start-up time Ton is more than with six Dead Time Tdead sums
Ovennodulation COEFFICIENT K H, wherein, when start-up time Ton and six Dead Time Tdead sums are more than ovennodulation COEFFICIENT K H, weak magnetic
The control permagnetic synchronous motor of control module 40 enters ovennodulation and list PI electric current loop weak magnetic control patterns.
It should be noted that because the value of T1+T2 is always in fluctuation, therefore T1 and T2 sums can be carried out at LPF
Reason, and then obtain start-up time Ton=Lowpass (T1+T2).
As shown in figure 4, when permagnetic synchronous motor enters ovennodulation with list PI electric current loop weak magnetic control patterns, weak magnetic control mould
The output of speed ring is given Idref by block 40, and according to the given Idref of D shaft currents and permagnetic synchronous motor
It is to obtain D shaft voltage Ud and same according to D shaft voltages Ud and permanent magnetism that D axle feedback currents Id_fbk carries out the regulation of D axle PI electric current loops
Step motor carries out weak magnetic into the Q shaft voltages Uq before ovennodulation and list PI electric current loop weak magnetic control patterns to permagnetic synchronous motor
Control.Thereby, it is possible to realize stable operation when permagnetic synchronous motor ovennodulation and weak magnetic.
In one embodiment of the invention, as shown in fig. 6, Q shaft voltages are given inclined during in order to prevent busbar voltage from changing
Difference is excessive, and the device of the embodiment of the present invention also includes:Q shaft voltages limit module 50.
Wherein, Q shaft voltages limitation module 50 calculates the end of permagnetic synchronous motor by the busbar voltage of permagnetic synchronous motor
Voltage max Vsmax between son, and permagnetic synchronous motor is entered according to voltage between terminals maximum Vsmax and ovennodulation COEFFICIENT K H
Enter ovennodulation carries out limitation treatment with the Q shaft voltages before list PI electric current loop weak magnetic control patterns.
Specifically, Vsmax can be calculated by formula (4), and then according to voltage between terminals maximum Vsmax and ovennodulation coefficient
KH is carried out at limitation to permagnetic synchronous motor into the Q shaft voltages Uq before ovennodulation and list PI electric current loop weak magnetic control patterns
Reason, can be Uq≤Vsmax*KH/0.866.
Further, after permagnetic synchronous motor enters ovennodulation and list PI electric current loop weak magnetic control patterns, mould is calculated
Block 20 is same always according to the D axle inductances of voltage between terminals maximum Vsmax and ovennodulation COEFFICIENT K H and permagnetic synchronous motor, permanent magnetism
Walk the angular rate of motor, the permanent magnet flux linkage calculating permagnetic synchronous motor of permagnetic synchronous motor and exit ovennodulation and list PI electric currents
Ring weak magnetic control pattern cuts out electric current ICut out.Judge module 30 is additionally operable to judge that whether D shaft currents are given more than cutting out electric current
ICut out, wherein, it is given more than cutting out electric current I in D shaft currentsCut outWhen, the control permagnetic synchronous motor of weak magnetic control module 40 was exited
Modulation and list PI electric current loop weak magnetic control patterns.
Specifically, electric current I extremely can be cut out by following formula (5)Cut out:
Wherein, Ld is the D axle inductances of permagnetic synchronous motor, and w is the angular rate of permagnetic synchronous motor,It is permanent-magnet synchronous
The permanent magnet flux linkage of motor.
It should be noted that working as Idref<When 0, it is believed that be weak magnetic, voltage vector weakens;Work as Idref>When 0, it is believed that be to increase
Magnetic, voltage vector enhancing.
To sum up, during the permagnetic synchronous motor ovennodulation of the embodiment of the present invention list PI electric current loops weak magnetic control device, pass through
Judge module judges whether permagnetic synchronous motor enters toning according to the action time of ovennodulation coefficient, two basic effectively vectors
System and list PI electric current loop weak magnetic control patterns, ovennodulation and list PI electric current loop weak magnetic control patterns are entered in permagnetic synchronous motor
When, given the output of speed ring as D shaft currents by weak magnetic control module, and given and permanent-magnet synchronous according to D shaft currents
The D axles feedback current of motor carries out the regulation of D axle PI electric current loops to obtain D shaft voltages, and then according to D shaft voltages and permanent magnet synchronous electric
Machine carries out weak magnetic control into the Q shaft voltages before ovennodulation and list PI electric current loop weak magnetic control patterns to permagnetic synchronous motor,
And by computing module according to the busbar voltage of permagnetic synchronous motor calculate permagnetic synchronous motor voltage between terminals maximum,
And after permagnetic synchronous motor enters ovennodulation and list PI electric current loop weak magnetic control patterns, by computing module according between terminal
The D axle inductances of voltage max and ovennodulation coefficient and permagnetic synchronous motor, the angular rate of permagnetic synchronous motor, permanent magnetism are same
What the permanent magnet flux linkage for walking motor calculated that permagnetic synchronous motor exits ovennodulation and list PI electric current loop weak magnetic control patterns cuts out electricity
Stream, and it is given according to D shaft currents by judge module and cut out electric current and judge whether permagnetic synchronous motor exits ovennodulation and list
PI electric current loop weak magnetic control patterns, and when D shaft currents are given more than electric current is cut out, control permanent magnetism same by weak magnetic control module
Step motor exits ovennodulation and list PI electric current loop weak magnetic control patterns.Thereby, it is possible to make permagnetic synchronous motor in ovennodulation and weak
Stable operation during magnetic, and the problem that D, Q axle are mutually coupled is can effectively solve the problem that, simplify PMSM control systems.
Further, the present invention proposes a kind of control system of permagnetic synchronous motor, and it includes above-mentioned implementation of the invention
The weak magnetic control device of the single PI electric current loops during permagnetic synchronous motor ovennodulation of example.
The control system of the permagnetic synchronous motor of the embodiment of the present invention, list during by above-mentioned permagnetic synchronous motor ovennodulation
The weak magnetic control device of PI electric current loops, can make permagnetic synchronous motor stable operation in ovennodulation and weak magnetic, and can be effective
Solve the problems, such as that D, Q axle are mutually coupled, simple structure.
In the description of the invention, it is to be understood that term " " center ", " longitudinal direction ", " transverse direction ", " length ", " width ",
" thickness ", " on ", D score, "front", "rear", "left", "right", " vertical ", " level ", " top ", " bottom " " interior ", " outward ", " up time
The orientation or position relationship of the instruction such as pin ", " counterclockwise ", " axial direction ", " radial direction ", " circumference " be based on orientation shown in the drawings or
Position relationship, is for only for ease of the description present invention and simplifies description, must rather than the device or element for indicating or imply meaning
With specific orientation, with specific azimuth configuration and operation, therefore must be not considered as limiting the invention.
Additionally, term " first ", " second " are only used for describing purpose, and it is not intended that indicating or implying relative importance
Or the implicit quantity for indicating indicated technical characteristic.Thus, define " first ", the feature of " second " can express or
Implicitly include at least one this feature.In the description of the invention, " multiple " is meant that at least two, such as two, three
It is individual etc., unless otherwise expressly limited specifically.
In the present invention, unless otherwise clearly defined and limited, term " installation ", " connected ", " connection ", " fixation " etc.
Term should be interpreted broadly, for example, it may be fixedly connected, or be detachably connected, or integrally;Can be that machinery connects
Connect, or electrically connect;Can be joined directly together, it is also possible to be indirectly connected to by intermediary, can be in two elements
The connection in portion or two interaction relationships of element, unless otherwise clearly restriction.For one of ordinary skill in the art
For, can as the case may be understand above-mentioned term concrete meaning in the present invention.
In the present invention, unless otherwise clearly defined and limited, fisrt feature second feature " on " or D score can be with
It is the first and second feature directly contacts, or the first and second features are by intermediary mediate contact.And, fisrt feature exists
Second feature " on ", " top " and " above " but fisrt feature are directly over second feature or oblique upper, or be merely representative of
Fisrt feature level height is higher than second feature.Fisrt feature second feature " under ", " lower section " and " below " can be
One feature is immediately below second feature or obliquely downward, or is merely representative of fisrt feature level height less than second feature.
In the description of this specification, reference term " one embodiment ", " some embodiments ", " example ", " specifically show
The description of example " or " some examples " etc. means to combine specific features, structure, material or spy that the embodiment or example are described
Point is contained at least one embodiment of the invention or example.In this manual, to the schematic representation of above-mentioned term not
Identical embodiment or example must be directed to.And, the specific features of description, structure, material or feature can be with office
Combined in an appropriate manner in one or more embodiments or example.Additionally, in the case of not conflicting, the skill of this area
Art personnel can be tied the feature of the different embodiments or example described in this specification and different embodiments or example
Close and combine.
Although embodiments of the invention have been shown and described above, it is to be understood that above-described embodiment is example
Property, it is impossible to limitation of the present invention is interpreted as, one of ordinary skill in the art within the scope of the invention can be to above-mentioned
Embodiment is changed, changes, replacing and modification.
Claims (11)
1. during a kind of permagnetic synchronous motor ovennodulation list PI electric current loops field weakening control method, it is characterised in that including following step
Suddenly:
Obtain the ovennodulation COEFFICIENT K H of the permagnetic synchronous motor, and calculate the permagnetic synchronous motor carry out SVPWM control when
Six basic effectively vectors in two the action time T1 and T2 of basic effectively vector;
Described in action time T1 and T2 according to the ovennodulation COEFFICIENT K H, described two basic effectively vectors judge whether control
Permagnetic synchronous motor enters ovennodulation and list PI electric current loop weak magnetic control patterns;
When the permagnetic synchronous motor enters the ovennodulation with list PI electric current loop weak magnetic control patterns, by the output of speed ring
It is given as D shaft currents, and the D axles feedback current of the and permagnetic synchronous motor given according to the D shaft currents carries out D axles PI
Electric current loop regulation obtaining D shaft voltages, and according to the D shaft voltages and the permagnetic synchronous motor enter the ovennodulation with
Q shaft voltages before single PI electric current loops weak magnetic control pattern carry out weak magnetic control to the permagnetic synchronous motor.
2. during permagnetic synchronous motor ovennodulation as claimed in claim 1 list PI electric current loops field weakening control method, its feature exists
In described in action time T1 and T2 according to the ovennodulation COEFFICIENT K H, described two basic effectively vectors judge whether control
Permagnetic synchronous motor enters ovennodulation and list PI electric current loop weak magnetic control patterns, including:
T1 and T2 sums are calculated, and the T1 and T2 sums are carried out low-pass filtering treatment to obtain start-up time Ton;
Judge the start-up time Ton and six Dead Time Tdead sums whether more than the ovennodulation COEFFICIENT K H;
If the start-up time Ton and six Dead Time Tdead sums are more than the ovennodulation COEFFICIENT K H, control is described
Permagnetic synchronous motor enters the ovennodulation and list PI electric current loop weak magnetic control patterns.
3. during permagnetic synchronous motor ovennodulation as claimed in claim 1 or 2 list PI electric current loops field weakening control method, its feature
It is that the ovennodulation COEFFICIENT K H meets relational expression:1 > KH > 0.8666.
4. during permagnetic synchronous motor ovennodulation as claimed in claim 1 list PI electric current loops field weakening control method, its feature exists
In also calculating the voltage between terminals maximum of the permagnetic synchronous motor by the busbar voltage of the permagnetic synchronous motor
Vsmax, and the permagnetic synchronous motor is entered according to the voltage between terminals maximum Vsmax and the ovennodulation COEFFICIENT K H
The ovennodulation carries out limitation treatment with the Q shaft voltages before list PI electric current loop weak magnetic control patterns.
5. during permagnetic synchronous motor ovennodulation as claimed in claim 4 list PI electric current loops field weakening control method, its feature exists
In after the permagnetic synchronous motor enters the ovennodulation and list PI electric current loop weak magnetic control patterns, also including:
According to the voltage between terminals maximum Vsmax and the D axles of the ovennodulation COEFFICIENT K H and the permagnetic synchronous motor
Inductance, the angular rate of the permagnetic synchronous motor, the permanent magnet flux linkage of the permagnetic synchronous motor calculate the permanent-magnet synchronous
What motor exited the ovennodulation and list PI electric current loop weak magnetic control patterns cuts out electric current ICut out;
Judge that the D shaft currents are given and whether cut out electric current I more than describedCut out;
If the D shaft currents are given to cut out electric current I more than describedCut out, then the permagnetic synchronous motor is controlled to exit the toning
System and list PI electric current loop weak magnetic control patterns.
6. during a kind of permagnetic synchronous motor ovennodulation list PI electric current loops weak magnetic control device, it is characterised in that including:
Acquisition module, the ovennodulation COEFFICIENT K H for obtaining the permagnetic synchronous motor;
Computing module, for calculate the permagnetic synchronous motor carry out in six basic effectively vectors when SVPWM is controlled two
The action time T1 and T2 of individual basic effectively vector;
Judge module, for being sentenced according to the action time T1 and T2 of the ovennodulation COEFFICIENT K H, described two basic effectively vectors
It is disconnected whether to control the permagnetic synchronous motor to enter ovennodulation and list PI electric current loop weak magnetic control patterns;
Weak magnetic control module, for entering the ovennodulation and list PI electric current loop weak magnetic control patterns in the permagnetic synchronous motor
When given the output of speed ring as D shaft currents, and and the permagnetic synchronous motor given according to the D shaft currents D axles
Feedback current carries out the regulation of D axle PI electric current loops to obtain D shaft voltages, and according to the D shaft voltages and the permanent magnet synchronous electric
Machine carries out weak into the Q shaft voltages before the ovennodulation and list PI electric current loop weak magnetic control patterns to the permagnetic synchronous motor
Magnetic control.
7. the weak magnetic control device of single PI electric current loops during permagnetic synchronous motor ovennodulation as claimed in claim 6, its feature
It is that the computing module is additionally operable to calculate T1 and T2 sums, and the T1 and T2 sums is carried out by low pass filter low
To obtain start-up time Ton, the judge module is further used for judging the start-up time Ton with six extremely for pass filter treatment
Whether area's time Tdead sum is more than the ovennodulation COEFFICIENT K H, wherein, in the start-up time Ton and six Dead Times
When Tdead sums are more than the ovennodulation COEFFICIENT K H, it is described that the weak magnetic control module controls the permagnetic synchronous motor to enter
Ovennodulation and list PI electric current loop weak magnetic control patterns.
8. during permagnetic synchronous motor ovennodulation as claimed in claims 6 or 7 list PI electric current loops weak magnetic control device, its feature
It is that the ovennodulation COEFFICIENT K H meets relational expression:1 > KH > 0.8666.
9. during permagnetic synchronous motor ovennodulation as claimed in claim 6 list PI electric current loops weak magnetic control device, its feature exists
In also including:
Q shaft voltages limit module, and the Q shaft voltages limitation module calculates described by the busbar voltage of the permagnetic synchronous motor
The voltage between terminals maximum Vsmax of permagnetic synchronous motor, and according to the voltage between terminals maximum Vsmax and the toning
The Q shaft voltages that COEFFICIENT K H processed enters before the ovennodulation and list PI electric current loop weak magnetic control patterns to the permagnetic synchronous motor
Carry out limitation treatment.
10. during permagnetic synchronous motor ovennodulation as claimed in claim 9 list PI electric current loops weak magnetic control device, its feature exists
In, after the permagnetic synchronous motor enters the ovennodulation and list PI electric current loop weak magnetic control patterns, the computing module
Always according to the D axles electricity of the voltage between terminals maximum Vsmax and the ovennodulation COEFFICIENT K H and the permagnetic synchronous motor
Sense, the permanent magnet flux linkage of the angular rate of the permagnetic synchronous motor, the permagnetic synchronous motor calculate the permanent magnet synchronous electric
What machine exited the ovennodulation and list PI electric current loop weak magnetic control patterns cuts out electric current ICut out, the judge module be additionally operable to judge
Whether the D shaft currents are given cuts out electric current I more than describedCut out, wherein, given in the D shaft currents and cut out electric current more than described
ICut outWhen, the weak magnetic control module controls the permagnetic synchronous motor to exit the ovennodulation with the control of list PI electric current loops weak magnetic
Pattern.
11. a kind of control systems of permagnetic synchronous motor, it is characterised in that including as any one of claim 6-10
The weak magnetic control device of list PI electric current loops during permagnetic synchronous motor ovennodulation.
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CN109889112A (en) * | 2019-03-20 | 2019-06-14 | 河北工业大学 | The efficiency optimization method of permanent magnet synchronous motor weak magnetic control single electric current adjuster |
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