CN110247599A - Asynchronous machine high-efficiency operation method based on end voltage optimization control - Google Patents
Asynchronous machine high-efficiency operation method based on end voltage optimization control Download PDFInfo
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- CN110247599A CN110247599A CN201910552136.6A CN201910552136A CN110247599A CN 110247599 A CN110247599 A CN 110247599A CN 201910552136 A CN201910552136 A CN 201910552136A CN 110247599 A CN110247599 A CN 110247599A
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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
- H02P21/14—Estimation or adaptation of machine parameters, e.g. flux, current or voltage
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Abstract
The invention discloses a kind of asynchronous motor high-efficiency operation methods based on end voltage optimization control, are related to the efficiency optimization field of asynchronous machine.By the way that MERS to be connected between power supply and asynchronous motor, the voltage at asynchronous motor stator end is adjusted using MERS, the high-efficiency operation of asynchronous motor may be implemented.Thus, the technical solution adopted by the present invention is that, three phase dynamic model and coordinate transform based on asynchronous motor, obtain the equivalent circuit of threephase asynchronous under rotating orthogonal coordinate system, and then derive the relationship between the controllable loss of asynchronous motor and stator terminal voltage, then controllable loss is asked to the first derivative of stator terminal voltage and enables it that the value for making that threephase asynchronous stator terminal voltage when reaching minimum is controllably lost in the case of different band carries just can be obtained equal to zero, the high-efficiency operation of asynchronous motor can be realized in voltage value when making the stator terminal voltage value of asynchronous motor reach minimum equal to the loss derived by the phase shifting control of MERS again.
Description
Technical field
The present invention relates to asynchronous machine technical field more particularly to a kind of efficiency optimization methods of asynchronous motor.
Background technique
Many advantages, such as asynchronous machine is simple, easily manufactured, cheap, sturdy and durable, reliable for operation because of its structure,
Many occasions instead of direct current generator, become widely used dynamic power machine.But in today that energy problem is increasingly severe,
Inefficiency of the asynchronous motor in underloading is also that cannot be neglected a problem.
Currently, asynchronous machine efficiency optimization research be divided into both direction: first is that motor body structure design improvement and
The application of new technology, new material, new process；Second is that the research to asynchronous motor control strategy.The former depends on new engineering material
The hardness condition such as improvement, masterful technique level of material, progress is slow, and the latter then makes some progress.And to different
The research direction of step motor control strategy includes the control strategy based on loss model, the control strategy based on search method, most again
Small stator current control strategy etc., wherein the most extensive to the research of the control strategy based on loss model.
Loss model method is to establish the loss model of asynchronous motor according to the asynchronous motor parameter grasped, and is parsed
Ground finds out control amount when making total losses minimum.What permissive waste modelling was found out is optimal stator electricity when enabling total losses minimum
Then the excitation component of stream goes the operation of control asynchronous motor further according to optimal value, is thus inevitably entirely controlling
Stator current excitation component adjuster, torque component adjuster and speed regulator are used in algorithm processed.And these adjusters are real
It is exactly pi regulator on border, the parameter for how adjusting this multiple pi regulator during use makes the performance of asynchronous motor
Being optimal is a great problem, and control is complex, this is also the deficiencies in the prior art place.
Summary of the invention
It is an object of the invention to overcome the deficiencies in the prior art, and propose a kind of based on the different of end voltage optimization control
Walk motor high-efficiency operation method.Although this method is still the control amount found out when making that minimum is lost based on loss model, control
Amount processed is no longer the excitation component of stator current, but the stator terminal voltage of asynchronous machine, therefore overcomes and adjust multiple PI controls
The difficulty of device parameter processed, furthermore the stator terminal voltage of threephase asynchronous is the phase shift control by MERS (magnetic energy reversion switch)
System realizes variation, and control method is simple.
In order to achieve the above object, the invention adopts the following technical scheme: MERS is connected on power supply and asynchronous motor
Between, the voltage of asynchronous motor stator side is adjusted using MERS when different band is carried, corresponding band is reached and carries situation
Stator voltage value when lower loss minimum, to realize the high-efficiency operation of asynchronous motor.
Preferably, the asynchronous motor is threephase asynchronous, and loss only includes the rotor in controllable loss
Copper loss and iron loss have ignored the troublesome mechanical loss of modeling comparison and stray loss.
Preferably, when deriving the relationship between the controllable loss of threephase asynchronous and stator voltage, it is fixed to have ignored
Then influence of the rotor leakage inductance to loss asks controllable loss to the first derivative of stator voltage and enables it that certain can be obtained equal to zero
One reaches stator voltage value when minimum with asynchronous machine loss in the case of carrying.
Preferably, the MERS is using full bridge structure, including switching tube S1, S2, S3, S4, diode VD1, VD2,
VD3, VD4 and capacitor C, wherein diode VD1, VD2, VD3, VD4 distinguish inverse parallel on switching tube S1, S2, S3, S4, constitute
Four bridge arms 1,2,3,4, capacitor C are connected between the tie point of bridge arm 1,2 and the tie point of bridge arm 3,4, remaining two bridges
Arm tie point connects power supply.
Preferably, the control method that the MERS is used is simple phase shifting control, specifically, detects the phase of power supply,
Postponed an angle γ, the pulse signal obtained at this time is given to switching tube S2 and S4, and the triggering of switching tube S1 and S3
Signal is just opposite with S2's and S4.And delay angle γ be by by the actual value of asynchronous motor stator phase voltage virtual value with
The theoretical value that loss reaches minimum value phase voltage effective value makees what difference was adjusted using PI, i.e. controllable by control γ
Asynchronous machine stator terminal voltage reaches voltage value when loss minimum.
Specific refinement step is as follows:
Step 1: according to the excitation parameter and short-circuit parameter of no-load test and short-circuit test measurement threephase asynchronous；
Step 2: according to the three phase dynamic model of asynchronous motor and coordinate transform, obtaining asynchronous motor in rotating orthogonal
Dynamic model in coordinate system (dq coordinate system)；
Step 3: the dynamic model obtained according to step 2 draws threephase asynchronous machine when considering iron loss under dq coordinate system
Equivalent circuit；
Step 4: deriving the relationship between the controllable loss of threephase asynchronous and its stator terminal voltage；
Step 5: situation being carried according to the band of threephase asynchronous, determines and reaches controllably loss
Stator terminal voltage when minimum；
Step 6: acquiring the phase-shift control angle γ of MERS according to the stator terminal voltage that step 5 obtains, driven under this phase shifting angle
Dynamic MERS is to make threephase asynchronous high-efficiency operation.
The beneficial effects of the present invention are: the asynchronous motor high efficiency fortune proposed by the present invention based on end voltage optimization control
Row method has searched out the pass between controllable loss and stator terminal voltage on the basis of threephase asynchronous loss model
System adjusts difficult problem so as to avoid multiple PI controller parameters in the prior art.In addition, the end voltage of asynchronous motor
Size is to realize variation by the phase shifting control of MERS, and control method is simple.
Detailed description of the invention
Fig. 1 is three phase coordinate systems and two-phase orthogonal coordinate system；
Fig. 2 is static two-phase orthogonal coordinate system and rotating orthogonal coordinate system；
Fig. 3 is the equivalent circuit of threephase asynchronous when considering iron loss under dq coordinate system；
Fig. 4 is the full bridge structure figure of single-phase MERS；
Fig. 5 is the current path of single-phase MRES in non-contiguous mode；
Fig. 6 is overall structure diagram of the invention；
Fig. 7 is the half-bridge structure figure of single-phase MERS；
Specific embodiment
Present invention will now be described in detail with reference to the accompanying drawings..It will be understood, however, that following specific embodiments are only
It is only the preferred technical solution of the present invention, and should not be construed limitation of the present invention.
The premise of efficiency-optimization control based on loss model is that have an accurate asynchronous machine loss model, therefore want
The no-load test and short-circuit test for first passing through threephase asynchronous come out its parametric measurement.No-load test measurement is three-phase
The excitation parameter Z of asynchronous motorm=Rm+jXm, short-circuit test measurement is short-circuit parameter Z1=R1+jX1σ, Z2=R2+jX2σ
(Z2、R2、X2σIt indicates that the value of stator side is arrived in conversion, for simplicity, indicates that the superscript " ' " of conversion is omitted, below
Herewith).By no-load test and short-circuit test, the stator resistance of the every phase of threephase asynchronous, leakage inductance, rotor resistance, leakage inductance,
Excitation resistance, magnetizing inductance are just measured out, and are got ready for the derivation of following equivalent circuit.
The three phase dynamic model (ignoring core loss) of asynchronous motor by flux linkage equations, voltage equation, torque equation and
Equation of motion composition, as follows respectively:
Te=-npLms[(iAia+iBib+iCic)sinθ+(iAib+iBic+iCia)sin(θ+120°)
+(iAic+iBia+iCib)sin(θ-120°)]
Wherein, ψs=[ψA ψB ψc]T；ψr=[ψa ψb ψc]T；is=[iA iB iC]T；ir=[ia ib ic]T；us=[uA
uB uC]T；ur=[ua ub uc]T；Subscript, which indicates uppercase amount, indicates the amount of stator side, and indicates the amount of lowercase
Then indicate the amount of rotor-side；θ indicates the electrical angle between rotor a axis and stator A axis；The rotary inertia of J expression asynchronous machine；np
Indicate the number of magnetic pole pairs of asynchronous machine；TeIndicate electromagnetic torque；TLIndicate load torque；The angular rate of ω expression rotor.
L in the above matrixlsThat indicate is each phase leakage inductance of stator, LlrThat indicate is each phase leakage inductance of rotor, LmsIndicate be
Stator mutual inductance, since stator and rotor umber of turn is equal after conversion, therefore rotor mutual inductance is equal to stator mutual inductance.
It can be seen from the above, the three phase dynamic model of asynchronous motor is sufficiently complex, analysis is got up extremely difficult, is carried out to it
Simplified method is exactly to utilize coordinate transform.Three phase coordinate system according to figure 1 and two-phase orthogonal coordinate system can release 3/2
The transformation matrix of transformation:
Static two-phase orthogonal coordinate system and rotating orthogonal coordinate system according to Fig.2, can release the change of 2s/2r transformation
Change matrix and its inverse matrix:
Further, it is possible to derive dynamic model of the threephase asynchronous under dq coordinate system when not considering iron loss:
Te=npLm(isqird-isdirq)
Wherein, LmIndicate that stator is coaxial with the rotor the mutual inductance between equivalent winding,LsIndicate the equivalent two-phase of stator
The self-induction of winding, Ls=Lm+Lls；LrIndicate the self-induction of two phase winding of rotor equivalent, Lr=Lm+Llr；ω1Indicate dq axis relative to
The angular velocity of rotation of stator.Since the equation of motion does not change with coordinate transform, the equation of motion is remained unchanged.
The iron loss of threephase asynchronous includes stator iron loss and rotor iron loss, since motor is when operating normally, slip
Rate very little, rotor frequency is very low, and rotor iron loss is much smaller than stator iron loss, therefore rotor iron loss is ignored when analysis.Consider
Model when iron loss is known as iron loss resistor coupled in parallel field excitation branch line model, available in conjunction with the dynamic model under dq coordinate system
The equivalent circuit of threephase asynchronous machine under dq coordinate system when consideration iron loss, as shown in Figure 3.
Under normal circumstances, the loss of threephase asynchronous should include controllable loss and uncontrollable loss.Due to uncontrollable
The ratio that shared total losses are lost is smaller, and modeling is very troublesome, its amplitude changes less, usually when motor operates normally in addition
Efficiency optimization of asynchronous motor strategy ignored, and only consider controllably to be lost.In equivalent circuit shown in Fig. 3, if enabled
Angular velocity of rotation ω of the dq axis relative to stator1Equal to the angular frequency of power supplys, i.e., usually said presses stator flux orientation, then
It can derive the relationship between the controllable loss of motor and stator magnetic linkage.During derivation, it is contemplated that leakage inductance Lls、LlrFar
Much smaller than mutual inductance Lm, therefore leakage inductance is ignored to simplify derivation process.In addition, empty according to the definition of space vector and with synthesis
Between the stator voltage equation of threephase asynchronous of vector representation can find the relationship of stator voltage Yu flux linkage space vector.
Finally, the expression formula being controllably lost is as follows:
Wherein,UmIndicate that asynchronous machine is fixed
The virtual value of the phase voltage at sub- end；RFeIndicate iron loss equivalent resistance, value is the inverse of asynchronous machine eddy current loss factor.
From the above equation, we can see that after giving a threephase asynchronous, a1、a2、a3、a4It is definite value, the angle of supply voltage
Frequency is also constant, therefore virtual value U of the controllable loss with phase voltagemWith electromagnetic torque TeIt is related.When motor is stablized
When operation, electromagnetic torque TeWith load torque TLIt is equal.Assuming that motor drag is constant torque load, then TeIt is also perseverance
It is fixed, at this moment controllable loss only with UmIt is related, seek PlossTo UmFirst derivative and to enable it be equal to zero available three different
Step motor makes that U when reaching minimum is controllably lost when different band carriesmValue, is shown below:
Fig. 4 is the structure chart of full-bridge MERS used by controlling threephase asynchronous stator terminal voltage.In the electricity of diagram
It presses under reference direction, hasIt sets up.In the vector triangle that these three vectors are constituted, according to triangle
Sine known to there is following relational expression to set up:
So that
What α in above formula was indicated isWithBetween angle；β indicate beWith electric currentBetween angle,
Namely the power-factor angle of load.It can be seen that the end voltage of load is related with the angle α, and exist between α and phase-shift control angle γ
Certain relationship, therefore by control γ, that is, controllable load end voltage so that threephase asynchronous is controllable
Loss reaches minimum.
As shown in figure 5, MRES completes positive charge, electric discharge, double sides in non-contiguous mode in a power cycle
Six road, reverse charging, electric discharge, double bypasses processes.And electric current flows only through anti-paralleled diode to MERS in the charge state, is putting
Electric current flows only through switching tube under electricity condition, and electric current had not only flowed through anti-paralleled diode but also flowed through switching tube under double bypass conditions.
In conclusion available overall structure of the invention, as shown in Figure 6.Since power supply and asynchronous machine are three
Phase shares 12 switching tubes so MERS also uses three-phase structure.G1-g12 in figure is the gate pole for indicating 12 switching tubes.
In addition to example set forth above, MERS can also have other different structures.Shown in Fig. 7 is half-bridge MERS, it
Only it is made of two switching tubes, two anti-paralleled diodes and a capacitor.Although the structure of half-bridge MERS is simpler, it
Voltage regulation limits are but smaller than full-bridge MERS, in some cases and are not suitable for.It is being balanced in addition, MERS can also work
Mode and direct current biasing mode.Example provided above is only preferred embodiment of the invention, as long as according to the claims in the present invention and originally
Simple equivalent changes and modifications made by description of the invention content should all belong to the range of the invention patent covering.
Claims (7)
1. a kind of asynchronous motor high-efficiency operation method based on end voltage optimization control, which is characterized in that MERS connects
Between power supply and asynchronous motor, the voltage of asynchronous motor stator side is adjusted using MERS when different band is carried, is made
It reaches the corresponding stator voltage value with when being lost minimum in the case of carrying, to realize the high-efficiency operation of asynchronous motor.
2. the asynchronous motor high-efficiency operation method according to claim 1 based on end voltage optimization control, feature
It is that the asynchronous motor is threephase asynchronous, and loss is only including the rotor copper loss and iron loss in controllable loss, suddenly
The troublesome mechanical loss of modeling comparison and stray loss are omited.
3. the asynchronous motor high-efficiency operation method according to claim 2 based on end voltage optimization control, feature
It is, when deriving the relationship between the controllable loss of threephase asynchronous and stator voltage, to have ignored rotor leakage inductance to damage
Then the influence of consumption is asked in the case of the first derivative to stator voltage is controllably lost and enables it that a certain band load can be obtained equal to zero
Asynchronous machine loss reaches stator voltage value when minimum.
4. the asynchronous motor high-efficiency operation method according to claim 1 based on end voltage optimization control, feature
It is that the MERS is using full bridge structure, including switching tube S1, S2, S3, S4, diode VD1, VD2, VD3, VD4 and capacitor
C, wherein diode VD1, VD2, VD3, VD4 distinguish inverse parallel on switching tube S1, S2, S3, S4, constitute four bridge arms 1,2,
3,4, capacitor C are connected between the tie point of bridge arm 1,2 and the tie point of bridge arm 3,4, and remaining two bridge arm tie points connect electricity
Source.
5. the asynchronous motor high-efficiency operation method according to claim 4 based on end voltage optimization control, feature
It is that the control method that the MERS is used is simple phase shifting control, specifically, detects the phase of power supply, postponed one
The pulse signal obtained at this time is given to switching tube S2 and S4 by angle γ, and the trigger signal of switching tube S1 and S3 and S2 and S4
It is just opposite.
6. the asynchronous motor high-efficiency operation method according to claim 5 based on end voltage optimization control, feature
It is phase voltage when delay angle γ is by the way that the actual value of asynchronous motor stator phase voltage virtual value and loss are reached minimum value
The theoretical value of virtual value makees what difference was adjusted using PI.
7. special according to claim 1 to the asynchronous motor high-efficiency operation method based on end voltage optimization control described in 6
Sign is that specific refinement step is as follows:
Step 1: according to the excitation parameter and short-circuit parameter of no-load test and short-circuit test measurement threephase asynchronous；
Step 2: according to the three phase dynamic model of asynchronous motor and coordinate transform, obtaining asynchronous motor in rotating orthogonal coordinate
It is the dynamic model in (dq coordinate system)；
Step 3: the dynamic model obtained according to step 2, draw under dq coordinate system consider iron loss when threephase asynchronous machine etc.
It is worth circuit；
Step 4: deriving the relationship between the controllable loss of threephase asynchronous and its stator terminal voltage；
Step 5: situation being carried according to the band of threephase asynchronous, determining makes controllably to be lost when reaching minimum under a certain loading condition
Stator terminal voltage；
Step 6: the phase-shift control angle γ of MERS being obtained according to the stator terminal voltage that step 5 obtains, is driven under this phase shifting angle
MERS is to make threephase asynchronous high-efficiency operation.
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| CN105790669A (en) * | 2016-03-07 | 2016-07-20 | 湖南工业大学 | Optimal energy saving voltage tracking method for asynchronous motor |
| WO2018119539A1 (en) * | 2016-12-29 | 2018-07-05 | Universidad De Santiago De Chile | Indirect method for constant slip control of asynchronous electric motors |
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2019
- 2019-06-25 CN CN201910552136.6A patent/CN110247599A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20120019188A1 (en) * | 2009-03-30 | 2012-01-26 | Kazuhiko Fukutani | Induction motor control device and induction motor group control system |
| CN102362426A (en) * | 2009-03-30 | 2012-02-22 | 新日本制铁株式会社 | Induction motor control device and induction motor group control system |
| CN105071735A (en) * | 2015-07-31 | 2015-11-18 | 西安理工大学 | Energy-saving control method of asynchronous motor based on T-1 simplified model |
| CN105790669A (en) * | 2016-03-07 | 2016-07-20 | 湖南工业大学 | Optimal energy saving voltage tracking method for asynchronous motor |
| WO2018119539A1 (en) * | 2016-12-29 | 2018-07-05 | Universidad De Santiago De Chile | Indirect method for constant slip control of asynchronous electric motors |
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