CN113364326A - Overmodulation method and system for 3D-SVPWM modulation strategy with minimum instantaneous error - Google Patents

Overmodulation method and system for 3D-SVPWM modulation strategy with minimum instantaneous error Download PDF

Info

Publication number
CN113364326A
CN113364326A CN202110746997.5A CN202110746997A CN113364326A CN 113364326 A CN113364326 A CN 113364326A CN 202110746997 A CN202110746997 A CN 202110746997A CN 113364326 A CN113364326 A CN 113364326A
Authority
CN
China
Prior art keywords
phase
modulation
voltage vector
reference voltage
svpwm
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202110746997.5A
Other languages
Chinese (zh)
Other versions
CN113364326B (en
Inventor
杨淑英
王顺
谢震
张兴
刘芳
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hefei University of Technology
Original Assignee
Hefei University of Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hefei University of Technology filed Critical Hefei University of Technology
Priority to CN202110746997.5A priority Critical patent/CN113364326B/en
Publication of CN113364326A publication Critical patent/CN113364326A/en
Application granted granted Critical
Publication of CN113364326B publication Critical patent/CN113364326B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/53—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M7/537—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
    • H02M7/539—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters with automatic control of output wave form or frequency
    • H02M7/5395—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters with automatic control of output wave form or frequency by pulse-width modulation
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/12—Arrangements for reducing harmonics from ac input or output
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/53—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M7/537—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
    • H02M7/5387—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration
    • H02M7/53871—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration with automatic control of output voltage or current
    • H02M7/53875—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration with automatic control of output voltage or current with analogue control of three-phase output
    • 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
    • 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
    • H02P21/0085—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation specially adapted for high speeds, e.g. above nominal speed
    • H02P21/0089—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation specially adapted for high speeds, e.g. above nominal speed using field weakening
    • 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
    • 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
    • H02P21/24—Vector control not involving the use of rotor position or rotor speed sensors
    • H02P21/28—Stator flux based control
    • 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
    • H02P25/00—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details
    • H02P25/02—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the kind of motor
    • H02P25/022—Synchronous motors
    • H02P25/024—Synchronous motors controlled by supply frequency
    • 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
    • H02P27/02—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using supply voltage with constant frequency and variable amplitude
    • 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

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Inverter Devices (AREA)

Abstract

A3D-SVPWM modulation strategy overmodulation method and system for minimizing output harmonic belongs to the technical field of inverter modulation, solves the problem of how to calculate the maximum linear modulation degree of a 3D-SVPWM modulation strategy, improves the modulation range of the 3D-SVPWM modulation strategy by the overmodulation technique while not changing the characteristics of simultaneously modulating a differential mode component and a common mode component of the 3D-SVPWM modulation strategy, obtains the maximum linear modulation degree of the 3D-SVPWM modulation strategy by calculation, provides a space modulation body judgment of a space modulation reference vector, establishes a corresponding compression plane constraint equation and an instantaneous error minimum compression scheme constraint equation when overmodulating, and keeps the instantaneous error of an output voltage vector when overmodulating to be minimum by the overmodulation technique on under the premise of not changing the characteristics of simultaneously modulating the differential mode component and the common mode component of the 3D-SVPWM strategy, and the modulation range of the 3D-SVPWM modulation strategy is widened.

Description

Overmodulation method and system for 3D-SVPWM modulation strategy with minimum instantaneous error
Technical Field
The invention belongs to the technical field of inverter modulation, and relates to a 3D-SVPWM (space vector pulse width modulation) modulation strategy overmodulation method and system with the minimum instantaneous error.
Background
The 3D-SVPWM (three-dimensional space vector pulse width modulation) strategy can simultaneously modulate the differential mode component and the common mode component of the reference voltage vector, so that the method is widely applied to zero-sequence circulating current control needing to modulate common mode voltage, such as open winding topological structures of a common direct current bus and a common neutral line double inverter, a three-phase four-leg inverter and the like. Compared with the traditional SVPWM (space vector pulse width modulation) strategy only focusing on differential mode component modulation, the 3D-SVPWM strategy is limited in the modulation output range of the differential mode component because the common mode component is modulated at the same time, so that the modulation range is expanded by related linear modulation range calculation and a corresponding over-modulation scheme, and the applicability of the 3D-SVPWM strategy is improved.
In the prior art, a document 3D-SVPWM modulation strategy of a four-leg three-level inverter (3D-SVPWM modulation strategy) with a publication date of 10 months in 2019 (anyhow, etc., power system and its automatic chemical report, 31 vol. 10, 125, 132) discloses that a 3D-SVPWM modulation strategy is applied to a four-leg three-level inverter, but the document does not specifically provide the maximum linear modulation degree of the 3D-SVPWM modulation strategy and a related overmodulation strategy. The document 'flux weakening control strategy of a common direct current bus open-winding permanent magnet synchronous motor' with publication date of 2018, 11 and 5 (year honing, etc., China Motor engineering reports, volume 38, No. 21, 6461, 6469 in 2018) discloses that a 3D-SVPWM modulation strategy is used for realizing zero-sequence circulating current closed-loop control of a common direct current bus double-inverter open-winding system, but the linear modulation range and related overmodulation strategy of the 3D-SVPWM modulation strategy are not given.
In summary, the prior art has the following problems: 1) for a 3D-SVPWM (space vector pulse width modulation) strategy, the prior art only provides a basic synthesis principle and an implementation process, and does not provide a linear modulation range, namely a maximum linear modulation degree, of the 3D-SVPWM strategy; 2) and a constraint scheme when the 3D-SVPWM modulation strategy is overmodulatied is not given, so that the overmodulation constraint scheme cannot be adopted to effectively expand the application range of the 3D-SVPWM modulation strategy.
Disclosure of Invention
The invention aims to calculate the maximum linear modulation degree of a 3D-SVPWM (space vector pulse width modulation) strategy, and on the premise of not changing the characteristic that the 3D-SVPWM strategy simultaneously modulates a differential mode component and a common mode component, the instantaneous error of an output voltage vector is kept to be minimum during overmodulation through an overmodulation technology, so that the modulation range of the 3D-SVPWM strategy is expanded.
The invention solves the technical problems through the following technical scheme:
A3D-SVPWM modulation strategy overmodulation method with minimum instantaneous error comprises the following steps:
step S1, calculating a reference voltage vector VrefOf the alpha-beta plane component m1Phase of
Figure BDA0003143310430000021
And modulation degree M1Calculating a reference voltage vector VrefGamma axis component V ofγAmplitude m of3And phase
Figure BDA0003143310430000022
Calculating a reference voltage vector VrefCharacteristic phase difference of
Figure BDA0003143310430000023
Step S2, according to the amplitude m in step S13And characteristic phase difference
Figure BDA0003143310430000024
Calculating the maximum linear modulation degree M of the 3D-SVPWM modulation strategymax1And maximum compression modulation degree Mmax2；
Step S3, according to the modulation degree M1Maximum linear modulation Mmax1And maximum compression modulation degree Mmax2And performing overmodulation judgment:
when calculating M1<Mmax1In the time, the linear modulation area is adopted for wave sending control, and the method comprises the following steps: according to Vα、VβAnd VγCalculating the base voltage vector action time t by using a 3D-SVPWM (space vector pulse width modulation) modulation strategy0、t1、t2And t7Wave generation control is carried out;
when calculating Mmax1≤M1≤Mmax2In the time, the wave generation control of the overmodulation region is adopted as the overmodulation region, and the method comprises the following steps:
when t is0T is not less than 07When the value is more than or equal to 0, the value is a circular arc area of an overmodulation area according to Vα、VβAnd VγCalculating the base voltage vector action time t by using a 3D-SVPWM (space vector pulse width modulation) modulation strategy0、t1、t2And t7Wave generation control is carried out;
when t is0<0 or t7<At 0, for the boundary region of the overmodulation region, for the reference voltage vector VrefThe α - β plane component of (a) is modified:
first according to Vα、VβAnd VγFor reference voltage vector VrefJudging the serial number of the modulation body in which the modulation body is positioned, and selecting a corresponding compression plane constraint equation according to the judged serial number of the modulation body;
then, the modified reference voltage vector alpha-axis component is obtained by simultaneous calculation with a constraint equation of the transient error minimum compression scheme
Figure BDA0003143310430000025
Reference voltage vector beta axis component
Figure BDA0003143310430000026
The constraint equation of the transient error minimum compression scheme is as follows:
Figure BDA0003143310430000027
wherein, P1、P2、P3Respectively in the selected compression plane constraint equations
Figure BDA0003143310430000031
Preceding coefficients and constant terms;
finally, according to the modified reference voltage vector alpha axis component
Figure BDA0003143310430000032
Modified reference voltage vector beta axis component
Figure BDA0003143310430000033
And VγCalculating the action time of the modified base voltage vector by using a 3D-SVPWM (space vector pulse width modulation) strategy
Figure BDA0003143310430000034
And
Figure BDA0003143310430000035
wave generation control is performed.
According to the technical scheme, the maximum linear modulation degree of the 3D-SVPWM modulation strategy is obtained through calculation, the judgment of a space modulation body where a space modulation reference vector is located is given, a corresponding compression plane constraint equation and a transient error minimum compression scheme constraint equation are combined during overmodulation, the transient error of an output voltage vector is kept to be minimum during overmodulation through the overmodulation technology on the premise that the characteristic that the 3D-SVPWM modulation strategy modulates a differential mode component and a common mode component simultaneously is not changed, and the modulation range of the 3D-SVPWM modulation strategy is expanded.
As a further improvement of the technical scheme of the invention, the reference voltage vector V is calculated in step S1refOf the alpha-beta plane component m1Phase of
Figure BDA0003143310430000036
And modulation degree M1The formula of (1) is:
Figure BDA0003143310430000037
wherein, Vα、VβAre respectively a reference voltage vector VrefProjection components of coordinate axes alpha and beta in a three-dimensional space coordinate system are converted into direct current voltage UdcPer-unit values.
As a further improvement of the technical scheme of the invention, the reference voltage vector V is calculated in step S1refGamma axis component V ofγAmplitude m of3And phase
Figure BDA0003143310430000038
The formula of (1) is:
Figure BDA0003143310430000039
wherein, Vγ，1Is a first orthogonal component, Vγ，2Is a second orthogonal component; the first and second orthogonal components are pairs VγOrthogonal decomposition is performed to obtain two components which are 90 degrees apart.
As a further improvement of the technical scheme of the invention, the reference voltage vector V is calculated in step S1refCharacteristic phase difference of
Figure BDA0003143310430000041
The calculation formula is as follows:
Figure BDA0003143310430000042
wherein,
Figure BDA0003143310430000043
is a reference voltageVector VrefGamma axis component V ofγThe phase of (a) is determined,
Figure BDA0003143310430000044
is a reference voltage vector VrefThe phase of the alpha-beta plane component of (a).
As a further improvement of the technical scheme of the invention, the maximum linear modulation degree M of the 3D-SVPWM modulation strategy is calculated in step S2max1And maximum compression modulation degree Mmax2The method specifically comprises the following steps:
defining a functional formula W1，
Figure BDA0003143310430000045
Defining a functional formula W2，
Figure BDA0003143310430000046
Wherein, theta1Has a value range of
Figure BDA0003143310430000047
At theta1Within the value range of (A) calculating the function formula W1Minimum value of W1minCalculating a functional formula W2Minimum value of W2minWhen W is1min≤W2minWhen M is in contact withmax1＝W1minWhen W is1min>W2minWhen M is in contact withmax1＝W2minCalculating a functional curve W1Sum function formula W2The function value of the curve intersection point is Mmax2。
As a further improvement of the technical solution of the present invention, the specific manner of judging the modulation entity number is as follows:
defining the intermediate variables judged by the serial number of the modulation body as a first variable A, a second variable B, a third variable C, a fourth variable N and a fifth variable A1A sixth variable B1The seventh variable C1The eighth variable N1Define the functional formula F1，
Figure BDA0003143310430000048
Definition function formula F2，F2＝2Vγ-VαDefine the functional formula F3，
Figure BDA0003143310430000049
Definition function formula F4，F4＝VβDefine the functional formula F5，
Figure BDA00031433104300000410
Definition function formula F6，
Figure BDA00031433104300000411
Then:
when F is present1When the value is more than or equal to 0, A is 1; when F is present1<When 0, A is 0; when F is present2When the value is more than or equal to 0, B is 1; when F is present2<When 0, B is 0; when F is present3When the carbon content is more than or equal to 0, C is 1; when F is present3<When 0, C is 0; n ═ a +2B + 4C;
when F is present4When the value is more than or equal to 0, A 11 is ═ 1; when F is present4<At 0, A 10; when F is present5When not less than 0, B 11 is ═ 1; when F is present5<At 0, B 10; when F is present6When not less than 0, C 11 is ═ 1; when F is present6<At 0, C1＝0；N1＝A1+2B1+4C1；
Each value of the fourth variable N corresponds to a modulation entity number, which is as follows: n ═ 5 corresponds to modulator 1; n1 corresponds to modulator 2; n ═ 3 corresponds to the modulator 3; n ═ 2 corresponds to the modulator 4; n ═ 6 corresponds to the modulator 5; n-4 corresponds to the modulator 6; when N is 0, an eighth variable N is required to be combined1Making a further determination of the value, wherein when N is present11 or N1When the value is 3, the value corresponds to the modulation body 2, and when N is14 or N1When the number is 5, the number is N, the modulation body 4 is corresponded12 or N1When it is 6, it corresponds to the modulator 6; when N is 7, an eighth variable N is required to be combined1Making a further determination of the value, wherein when N is present12 or N13-hour correspondence modulationBody 1, when N 11 or N1When the number is 5, the number is N, the modulation body 3 is concerned14 or N1When 6, the corresponding modulator 5 is used.
As a further improvement of the technical solution of the present invention, the specific way of selecting the corresponding compression plane constraint equation by the judged serial number of the modulation body is as follows:
the compression plane constraint equation of the modulator 1 is:
Figure BDA0003143310430000051
the compression plane constraint equation of the modulation volume 2 is:
Figure BDA0003143310430000052
the compression plane constraint equation of the modulator body 3 is:
Figure BDA0003143310430000053
the compression plane constraint equation of the modulation volume 4 is:
Figure BDA0003143310430000054
the compression plane constraint equation of the modulator 5 is:
Figure BDA0003143310430000055
the compression plane constraint equation for the modulator 6 is:
Figure BDA0003143310430000056
a system applied to the output harmonic minimization 3D-SVPWM modulation strategy overmodulation method comprises the following steps: first DC source Udc1A second DC source Udc2The three-phase two-level inverter comprises a first three-phase two-level inverter VSI1, a second three-phase two-level inverter VSI2, a three-phase stator winding OEWIM, a neutral line I, a capacitor C1, a capacitor C2, a capacitor C3 and a capacitor C4;
the capacitor C1 and the capacitor C2 are connected in series and then connected to a first direct current source Udc1OfA common node between the positive current bus P and the negative current bus N and between the capacitor C1 and the capacitor C2 is marked as a point O; the capacitor C3 and the capacitor C4 are connected in series and then connected to a second direct current source Udc2Between the positive dc bus P 'and the negative dc bus N', the common node of the capacitors C3 and C4 is denoted as point O ', the neutral line I connects the point O and the point O', and the first dc source Udc1And a second DC source Udc2All direct current voltages are Udc；
In the three-phase bridge arm of the first three-phase two-level inverter VSI1, each phase of bridge arm includes 2 switching tubes with anti-parallel diodes, that is, the first three-phase two-level inverter VSI1 includes 6 switching tubes with anti-parallel diodes in total, and 6 switching tubes are respectively marked as Sn1jWherein n represents the phase sequence, n is a, b, c, j represents the serial number of the switching tube, and j is 1, 2; the three-phase bridge arms of the first three-phase two-level inverter VSI1 are connected in parallel between the direct current positive bus P and the direct current negative bus N, namely a switch tube Sa11、Sb11、Sc11The collectors are connected in parallel and then are connected with a direct current positive bus P and a switching tube Sa12、Sb12、Sc12The emitting electrodes are connected in parallel and then connected with a direct current negative bus N; in the three-phase leg of the first three-phase two-level inverter VSI1, the switching tube Sa11And a switching tube Sa12Series, switch tube Sb11And a switching tube Sb12Series, switch tube Sc11And a switching tube Sc12The connection points of the series connection are respectively marked as three-phase bridge arm middle points a of the first three-phase two-level inverter VSI11、b1、c1；
In the three-phase bridge arm of the second three-phase two-level inverter VSI2, each phase of bridge arm includes 2 switching tubes with anti-parallel diodes, that is, the second three-phase two-level inverter VSI2 includes 6 switching tubes with anti-parallel diodes in total, and 6 switching tubes are respectively marked as Sn2j(ii) a The three-phase bridge arms of the second three-phase two-level inverter VSI2 are connected in parallel between the direct current positive bus P 'and the direct current negative bus N', namely a switch tube Sa21、Sb21、Sc21The collectors are connected in parallel and then connected with a direct current positive bus P', and a switching tube Sa22、Sb22、Sc22The emitting electrodes are connected in parallel and then connected with a direct current negative bus N'; in thatIn a three-phase arm of a second three-phase two-level inverter VSI2, a switching tube Sa21And a switching tube Sa22Series, switch tube Sb21And a switching tube Sb22Series, switch tube Sc21And a switching tube Sc22The connection points of the series connection are respectively marked as three-phase bridge arm middle points a of the second three-phase two-level inverter VSI22、b2、c2；
The three-phase stator winding OEWIM comprises three-phase windings, and the left ports of the A-phase winding, the B-phase winding and the C-phase winding are respectively connected with the three-phase bridge arm midpoint a of the first three-phase two-level inverter VSI11、b1、c1The right ports of the A-phase winding, the B-phase winding and the C-phase winding are respectively connected with the three-phase bridge arm midpoint a of the second three-phase two-level inverter VSI22、b2、c2。
The invention has the advantages that:
according to the technical scheme, the maximum linear modulation degree of the 3D-SVPWM modulation strategy is obtained through calculation, the judgment of a space modulation body where a space modulation reference vector is located is given, a corresponding compression plane constraint equation and a compression scheme constraint equation with the minimum instantaneous error are combined during overmodulation, the instantaneous error of an output voltage vector is kept to be minimum during overmodulation through the overmodulation technology while the characteristic that the differential mode component and the common mode component are simultaneously modulated by the 3D-SVPWM modulation strategy is not changed, and the modulation range of the 3D-SVPWM modulation strategy is expanded.
Drawings
FIG. 1 is a common-neutral open-winding topology as referred to in the present invention;
FIG. 2 is a flow chart of an over-modulation operation in any of the modulators of the embodiments of the present invention;
FIG. 3 is an illustration of a general modulation scheme of a 3D-SVPWM modulation strategy according to an embodiment of the present invention;
FIG. 4 is a diagram illustrating a 3D-SVPWM modulation strategy modulator according to an embodiment of the present invention;
FIG. 5 shows the gamma component V of the reference voltage vector calculated in step S1 when the parameters are accurateγAmplitude m of3Schematic diagram of the variation of (1);
FIG. 6 shows the reference voltage vector V calculated in step S1 when the parameters are accurate in the experimentrefCharacteristic phase difference of
Figure BDA0003143310430000071
Schematic diagram of the variation of (1);
FIG. 7 is a functional curve W plotted in step S2 when the parameters are accurate in the experiment1Sum function formula W2Curve and maximum linear modulation degree M of 3D-SVPWM modulation strategy obtained by calculationmax1And maximum compression modulation degree Mmax2A schematic diagram;
fig. 8 is a schematic diagram of a change in amplitude of a fundamental voltage of a total output of a common-neutral open-winding electric drive system when modulation degree M is 0.6 to 0.8 is modulated by using a 3D-SVPWM strategy under the condition that each parameter is accurate in an experiment;
FIG. 9 is a diagram depicting the principles and features of the present invention;
fig. 10 is a graph showing the trend of the variation of the fourth variable N in the judgment of the modulator measured in the experiment.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The technical scheme of the invention is further described by combining the drawings and the specific embodiments in the specification:
example one
FIG. 1 is a three-phase two-level voltage source inverter topology as referred to in the present invention, from which it can be seen that the common neutral open winding electric drive system topology as referred to in the present strategy comprises a first DC source Udc1A second DC source Udc2A first three-phase two-level inverter VSI1, a second threeThe three-phase motor comprises a two-phase inverter VSI2, a three-phase stator winding OEWIM, a neutral line I, a capacitor C1, a capacitor C2, a capacitor C3 and a capacitor C4;
the capacitor C1 and the capacitor C2 are connected in series and then connected to a first direct current source Udc1Between the direct current positive bus P and the direct current negative bus N, a common node of the capacitor C1 and the capacitor C2 is marked as a point O; the capacitor C3 and the capacitor C4 are connected in series and then connected to a second direct current source Udc2Between the positive dc bus P 'and the negative dc bus N', the common node of the capacitors C3 and C4 is denoted as point O ', the neutral line I connects the point O and the point O', and the first dc source Udc1And a second DC source Udc2All direct current voltages are Udc；
In the three-phase bridge arm of the first three-phase two-level inverter VSI1, each phase of bridge arm includes 2 switching tubes with anti-parallel diodes, that is, the first three-phase two-level inverter VSI1 includes 6 switching tubes with anti-parallel diodes in total, and 6 switching tubes are respectively marked as Sn1jWherein n represents the phase sequence, n is a, b, c, j represents the serial number of the switching tube, and j is 1, 2; the three-phase bridge arms of the first three-phase two-level inverter VSI1 are connected in parallel between the direct current positive bus P and the direct current negative bus N, namely a switch tube Sa11、Sb11、Sc11The collectors are connected in parallel and then are connected with a direct current positive bus P and a switching tube Sa12、Sb12、Sc12The emitting electrodes are connected in parallel and then connected with a direct current negative bus N; in the three-phase leg of the first three-phase two-level inverter VSI1, the switching tube Sa11And a switching tube Sa12Series, switch tube Sb11And a switching tube Sb12Series, switch tube Sc11And a switching tube Sc12The connection points of the series connection are respectively marked as three-phase bridge arm middle points a of the first three-phase two-level inverter VSI11、b1、c1；
In the three-phase bridge arm of the second three-phase two-level inverter VSI2, each phase of bridge arm includes 2 switching tubes with anti-parallel diodes, that is, the second three-phase two-level inverter VSI2 includes 6 switching tubes with anti-parallel diodes in total, and 6 switching tubes are respectively marked as Sn2j(ii) a The three-phase bridge arms of the second three-phase two-level inverter VSI2 are connected in parallel between a direct current positive bus P' and a direct current negative bus NI.e. switching tube Sa21、Sb21、Sc21The collectors are connected in parallel and then connected with a direct current positive bus P', and a switching tube Sa22、Sb22、Sc22The emitting electrodes are connected in parallel and then connected with a direct current negative bus N'; in the three-phase leg of the second three-phase two-level inverter VSI2, the switching tube Sa21And a switching tube Sa22Series, switch tube Sb21And a switching tube Sb22Series, switch tube Sc21And a switching tube Sc22The connection points of the series connection are respectively marked as three-phase bridge arm middle points a of the second three-phase two-level inverter VSI22、b2、c2；
The three-phase stator winding OEWIM comprises three-phase windings, and the left ports of the A-phase winding, the B-phase winding and the C-phase winding are respectively connected with the three-phase bridge arm midpoint a of the first three-phase two-level inverter VSI11、b1、c1The right ports of the A-phase winding, the B-phase winding and the C-phase winding are respectively connected with the three-phase bridge arm midpoint a of the second three-phase two-level inverter VSI22、b2、c2。
The invention comprises the following steps:
fig. 2 is a flow chart of overmodulation operation in any of the modulators according to the embodiments of the present invention, corresponding to steps 1 to 3.
Step 1, setting a reference voltage vector to be modulated of a three-phase two-level inverter as VrefThe reference voltage vector is VrefCorresponding to the reference voltage vector output by any one of the two inverters VSI1 and VSI2, and referring to the voltage vector VrefDirect current voltage U is used for projection components of coordinate axes alpha, beta and gamma in a three-dimensional space coordinate systemdcPerforming per unit, and respectively marking as the alpha-axis component V of the reference voltage vectorαReference voltage vector beta axis component VβReference voltage vector gamma axis component VγUsing the reference voltage vector alpha-axis component VαReference voltage vector beta axis component VβCalculating to obtain a reference voltage vector VrefOf the alpha-beta plane component m1Reference voltage vector VrefPhase of the alpha-beta plane component of (1)
Figure BDA0003143310430000091
And a reference voltage vector VrefModulation degree M corresponding to the alpha-beta plane component of1The calculation formula is as follows:
Figure BDA0003143310430000092
for reference voltage vector gamma axis component VγOrthogonal decomposition is carried out to obtain two components with 90-degree phase difference, which are respectively marked as gamma-axis components V of reference voltage vectorγFirst orthogonal component V ofγ，1And a reference voltage vector gamma-axis component VγSecond orthogonal component V ofγ，2Calculating the gamma-axis component V of the reference voltage vectorγAmplitude m of3And a reference voltage vector gamma-axis component VγPhase of
Figure BDA0003143310430000093
The calculation formula is as follows:
Figure BDA0003143310430000094
calculating a reference voltage vector VrefCharacteristic phase difference of
Figure BDA0003143310430000101
The calculation formula is as follows:
Figure BDA0003143310430000102
step 2, obtaining the gamma axis component V of the reference voltage vector according to the step 1γAmplitude m of3And reference voltage vector VrefCharacteristic phase difference of
Figure BDA0003143310430000103
Calculating the maximum linear modulation degree M of the 3D-SVPWM modulation strategymax1And maximum compression modulation degree Mmax2：
Defining a functional formula W1The following were used:
Figure BDA0003143310430000104
defining a functional formula W2The following were used:
Figure BDA0003143310430000105
wherein theta is1Has a value range of
Figure BDA0003143310430000106
At theta1Within the value range of (A) calculating the function formula W1Minimum value of W1minCalculating a functional formula W2Minimum value of W2minWhen W is1min≤W2minWhen M is in contact withmax1＝W1minWhen W is1min>W2minWhen M is in contact withmax1＝W2minCalculating a functional curve W1Sum function formula W2The function value of the curve intersection point is Mmax2。
Step 3, obtaining a reference voltage vector V according to the step 1 and the step 2refModulation degree M corresponding to the alpha-beta plane component of1And the maximum linear modulation degree M of the 3D-SVPWM modulation strategymax1And maximum compression modulation degree Mmax2Carrying out overmodulation judgment;
when calculating M1<Mmax1If so, the step 3.1 is carried out, namely the linear modulation region is obtained;
when calculating Mmax1≤M1≤Mmax2If so, entering a step 3.2 for an overmodulation region;
step 3.1, calculate M1<Mmax1Linear modulation region of time according to the reference voltage vector alpha-axis component VαReference voltage vector beta axis component VβAnd a reference voltage vector gamma-axis component VγCalculating the base voltage vector action time t by using a 3D-SVPWM (space vector pulse width modulation) modulation strategy0When the base voltage vector actsTime t1Base voltage vector action time t2And base voltage vector action time t7Wave generation control is carried out; time t0、t1、t2、t7The specific calculation process of (2) is referred to pages 6461 and 6469 of a literature "flux weakening control strategy of a common direct current bus open winding permanent magnet synchronous motor" (yearly honing, etc., China Motor engineering, vol 38, No. 21 in 2018), the publication date of which is 2018, 11, month and 5.
Step 3.2, calculate Mmax1≤M1≤Mmax2An overmodulation region of time;
step 3.21, according to the reference voltage vector alpha axis component VαReference voltage vector beta axis component VβAnd a reference voltage vector gamma-axis component VγCalculating the base voltage vector action time t by using a 3D-SVPWM (space vector pulse width modulation) modulation strategy0Base voltage vector action time t1Base voltage vector action time t2And base voltage vector action time t7；
When t is0T is not less than 07When the value is more than or equal to 0, the value is a circular arc area of the overmodulation area, and the step 3.22 is carried out;
when t is0<0 or t7<When 0, the boundary area of the overmodulation area is reached, and the step 3.23 is carried out;
step 3.22, the action time t of the basic voltage vector is obtained by calculation0Base voltage vector action time t1Base voltage vector action time t2And base voltage vector action time t7Wave generation control is carried out;
step 3.23, for reference voltage vector VrefIs modified according to the alpha-axis component V of the reference voltage vectorαReference voltage vector beta axis component VβAnd a reference voltage vector gamma-axis component VγFor reference voltage vector VrefThe modulation body is used for judging the serial number of the modulation body, the corresponding compression plane constraint equation is selected according to the judged serial number of the modulation body, and then the modified reference voltage vector alpha-axis component is obtained by simultaneous calculation with the transient error minimum compression scheme constraint equation
Figure BDA0003143310430000111
Reference voltage vector beta axis component
Figure BDA0003143310430000112
According to the alpha-axis component of the modified reference voltage vector
Figure BDA0003143310430000113
Reference voltage vector beta axis component
Figure BDA0003143310430000114
And a reference voltage vector gamma-axis component VγCalculating the base voltage vector action time by using a 3D-SVPWM modulation strategy
Figure BDA0003143310430000115
Base voltage vector action time
Figure BDA0003143310430000116
Base voltage vector action time
Figure BDA0003143310430000117
And base voltage vector action time
Figure BDA0003143310430000118
Wave generation control is carried out; time of day
Figure BDA0003143310430000119
The specific calculation process of (2) is referred to 6461-6469 pages in the literature "flux weakening control strategy of common direct current bus open winding permanent magnet synchronous motor" (yearly honing, etc., china motor engineering report, vol 38, vol 21, in 2018), whose publication date is 2018, 11/5/11/5.
The specific way of judging the modulation body serial number is as follows: defining the intermediate variables judged by the serial number of the modulation body as a first variable A, a second variable B, a third variable C, a fourth variable N and a fifth variable A1A sixth variable B1The seventh variable C1The eighth variable N1Define the functional formula F1，
Figure BDA00031433104300001110
Definition function formula F2，F2＝2Vγ-VαDefine the functional formula F3，
Figure BDA00031433104300001111
Definition function formula F4，F4＝VβDefine the functional formula F5，
Figure BDA00031433104300001112
Definition function formula F6，
Figure BDA0003143310430000121
Then:
when F is present1When the value is more than or equal to 0, A is 1,
when F is present1<When the number is 0, A is 0,
when F is present2When the value is more than or equal to 0, B is 1,
when F is present2<When the number of the carbon atoms is 0, B is 0,
when F is present3When the carbon content is more than or equal to 0, C is 1,
when F is present3<When the ratio is 0, C is 0,
N＝A+2B+4C，
when F is present4When the value is more than or equal to 0, A1＝1，
When F is present4<At 0, A1＝0，
When F is present5When not less than 0, B1＝1，
When F is present5<At 0, B1＝0，
When F is present6When not less than 0, C1＝1，
When F is present6<At 0, C1＝0，
N1＝A1+2B1+4C1，
Each value of the fourth variable N corresponds to a modulation entity number, which is as follows:
n ═ 5 corresponds to modulator 1; n1 corresponds to modulator 2; n ═ 3 corresponds to the modulator 3; n-2 corresponds toA modulator 4; n ═ 6 corresponds to the modulator 5; n-4 corresponds to the modulator 6; when N is 0, an eighth variable N is required to be combined1Making a further determination of the value, wherein when N is present11 or N1When the value is 3, the value corresponds to the modulation body 2, and when N is14 or N1When the number is 5, the number is N, the modulation body 4 is corresponded12 or N1When it is 6, it corresponds to the modulator 6; when N is 7, an eighth variable N is required to be combined1Making a further determination of the value, wherein when N is present12 or N1When the value is 3, the value corresponds to the modulation body 1, and when N is11 or N1When the number is 5, the number is N, the modulation body 3 is concerned14 or N1When 6, the corresponding modulator 5 is used.
The corresponding relation between different values of the fourth variable N and the serial number of the modulation body is shown in the following table:
Figure BDA0003143310430000131
fig. 3 is an illustration diagram of a total modulation body of a 3D-SVPWM modulation strategy in an embodiment of the present invention, which is the total modulation body of the 3D-SVPWM modulation strategy on an α - β - γ three-dimensional space.
Fig. 4 is a diagram illustrating a 3D-SVPWM modulation strategy modulation entity separately according to an embodiment of the present invention, where the total modulation entity in fig. 3 is divided into six modulation entities and numbered.
The specific way of selecting the corresponding compression plane constraint equation according to the judged modulation body serial number is as follows:
the compression plane constraint equation of the modulator 1 is:
Figure BDA0003143310430000132
the compression plane constraint equation of the modulation volume 2 is:
Figure BDA0003143310430000133
the compression plane constraint equation of the modulator body 3 is:
Figure BDA0003143310430000134
compression plane confinement of a modulation 4The equation is:
Figure BDA0003143310430000135
the compression plane constraint equation of the modulator 5 is:
Figure BDA0003143310430000136
the compression plane constraint equation for the modulator 6 is:
Figure BDA0003143310430000137
the transient error minimum compression scheme constraint equation is as follows:
Figure BDA0003143310430000138
wherein, P1、P2、P3Respectively in the selected compression plane constraint equations
Figure BDA0003143310430000139
Preceding coefficients and constant terms;
namely, the wave-sending control of the 3D-SVPWM modulation strategy with overmodulation is realized.
In order to verify the effectiveness of the invention, the invention was experimentally verified. Topological structure first direct current source U of common neutral open winding electric drive systemdc1And a second DC source Udc2D.c. voltage Udc280V, the main circuits of the first three-phase two-level inverter VSI1 and the second three-phase two-level inverter VSI2 are composed of Mitsubishi intelligent IGBT power module PM100CLA120, and the switching frequency fsThe dead band is set at 3 mus at 9600 Hz. Using a three-phase asynchronous motor as a load, the asynchronous motor parameters: rated power pn3kW, rated phase voltage UN220V, stator resistance Rs1.93 omega, mutual inductance Lm0.19H, stator inductance Ls0.21H, pole pair number P2, operating frequency fe50 Hz. 180-degree decoupling of reference voltage vector required to be modulated for common-neutral open-winding electric drive systemThe reference voltage vectors which are averagely distributed to the first three-phase two-level inverter VSI1 and the second three-phase two-level inverter VSI2 for modulation are equal in size and opposite in direction.
Fig. 5 shows the gamma component V of the reference voltage vector calculated in step 1 for the first three-phase two-level inverter VSI1γAmplitude m of3Approximately 0.212, corresponding to a common mode voltage requirement of 59.4V for the first three-phase two-level inverter VSI1, and 118.72V for the total common mode voltage requirement of the common neutral open winding electric drive system.
Fig. 6 shows the calculation of the reference voltage vector V of the first three-phase two-level inverter VSI1 in step 1refCharacteristic phase difference
Figure BDA0003143310430000141
About 2.4.
FIG. 7 shows the gamma component V at the reference voltage vectorγAmplitude m of3About 0.212, reference voltage vector VrefCharacteristic phase difference of
Figure BDA0003143310430000147
About 2.4 by step 21Sum function formula W2Curve, maximum linear modulation degree M of the corresponding first three-phase two-level inverter VSI1 obtained through calculation by using 3D-SVPWM modulation strategymax10.6096, namely, the maximum output of the first three-phase two-level inverter VSI1 is linearly modulated by using a 3D-SVPWM modulation strategy, and the maximum compression modulation degree M is calculatedmax2Is 1.04.
Fig. 8 shows a reference voltage vector V of a first three-phase two-level inverter VSI1refModulation degree M corresponding to the alpha-beta plane component of1And when the voltage rises from 0.6 to 0.8, the amplitude of the fundamental wave voltage of the total output of the common neutral open-winding electric drive system is modulated by using a 3D-SVPWM modulation strategy. Therefore, the over-modulation strategy can effectively break through the traditional linear modulation maximum constraint of 216.8V and increase the amplitude of the fundamental wave voltage of the total output to about 265V, and effectively increase the modulation range of the 3D-SVPWM modulation strategy。
As shown in FIG. 9, VrefIs a vector of reference voltages, V*After the steps 1-3 of the technical scheme of the invention, the modified reference voltage vector alpha axis component is obtained by calculation
Figure BDA0003143310430000142
Reference voltage vector beta axis component
Figure BDA0003143310430000143
And a reference voltage vector gamma-axis component VγA modified reference voltage vector composed of coordinates. Modified reference voltage vector V*Straight line of space with vertex on outer surface of modulator
Figure BDA0003143310430000144
Straight line of space
Figure BDA0003143310430000145
And a reference voltage vector VrefThe common-mode component output is ensured to follow the instruction due to the equal height. The compression scheme of the technical scheme of the invention restrains the equation to ensure that the reference voltage vector VrefStraight line to space
Figure BDA0003143310430000146
Making a vertical line, wherein the vertical foot is the modified reference voltage vector V*And (4) a vertex. Reference voltage vector VrefModified reference voltage vector V*Vertex and spatial straight line of
Figure BDA0003143310430000151
The projections on the α β plane are respectively noted as point D, G and a straight line
Figure BDA0003143310430000152
Vector
Figure BDA0003143310430000153
The modified reference voltage vector V of the technical scheme of the invention*And a reference voltage vector VrefDifferential mode instantaneous error vector therebetween, composed of
Figure BDA0003143310430000154
Perpendicular to
Figure BDA0003143310430000155
It can be seen that the instantaneous error vector of the technical scheme of the invention is the minimum.
In the experiment, the determination of the modulation entity number was also verified in the following manner.
As can be seen from fig. 10, the value of the fourth variable N varies sequentially within one fundamental wave period, corresponding to the reference voltage vector VrefThe modulation body 1 to the modulation body 6 rotate continuously for one circle, and the judgment of the modulation body serial number is accurate and effective.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims (8)

1. A3D-SVPWM modulation strategy overmodulation method with minimum instantaneous error is characterized by comprising the following steps:
step S1, calculating a reference voltage vector VrefOf the alpha-beta plane component m1Phase of
Figure FDA0003143310420000011
And modulation degree M1Calculating a reference voltage vector VrefGamma axis component V ofγAmplitude m of3And phase
Figure FDA0003143310420000012
Calculating a reference voltage vector VrefCharacteristic phase difference of
Figure FDA0003143310420000013
Step S2, according to the amplitude m in step S13And characteristic phase difference
Figure FDA0003143310420000017
Calculating the maximum linear modulation degree M of the 3D-SVPWM modulation strategymax1And maximum compression modulation degree Mmax2；
Step S3, according to the modulation degree M1Maximum linear modulation Mmax1And maximum compression modulation degree Mmax2And performing overmodulation judgment:
when calculating M1<Mmax1In the time, the linear modulation area is adopted for wave sending control, and the method comprises the following steps: according to Vα、VβAnd VγCalculating the base voltage vector action time t by using a 3D-SVPWM (space vector pulse width modulation) modulation strategy0、t1、t2And t7Wave generation control is carried out;
when calculating Mmax1≤M1≤Mmax2In the time, the wave generation control of the overmodulation region is adopted as the overmodulation region, and the method comprises the following steps:
when t is0T is not less than 07When the value is more than or equal to 0, the value is a circular arc area of an overmodulation area according to Vα、VβAnd VγCalculating the base voltage vector action time t by using a 3D-SVPWM (space vector pulse width modulation) modulation strategy0、t1、t2And t7Wave generation control is carried out;
when t is0<0 or t7<At 0, for the boundary region of the overmodulation region, for the reference voltage vector VrefThe α - β plane component of (a) is modified:
first according to Vα、VβAnd VγFor reference voltage vector VrefJudging the serial number of the modulation body in which the modulation body is positioned, and selecting a corresponding compression plane constraint equation according to the judged serial number of the modulation body;
and then, the modified reference voltage vector is obtained by simultaneous calculation with a constraint equation of the transient error minimum compression schemeComponent of quantity alpha axis
Figure FDA0003143310420000014
Reference voltage vector beta axis component
Figure FDA0003143310420000015
The constraint equation of the transient error minimum compression scheme is as follows:
Figure FDA0003143310420000016
wherein, P1、P2、P3Respectively in the selected compression plane constraint equations
Figure FDA0003143310420000021
Preceding coefficients and constant terms;
finally, according to the modified reference voltage vector alpha axis component
Figure FDA0003143310420000022
Modified reference voltage vector beta axis component
Figure FDA0003143310420000023
And VγCalculating the action time of the modified base voltage vector by using a 3D-SVPWM (space vector pulse width modulation) strategy
Figure FDA0003143310420000024
And
Figure FDA0003143310420000025
wave generation control is performed.
2. The overmodulation method according to claim 1, wherein the reference voltage vector V is calculated in step S1refOf the alpha-beta plane component m1Phase of
Figure FDA0003143310420000026
And modulation degree M1The formula of (1) is:
Figure FDA0003143310420000027
3. the overmodulation method according to claim 2, wherein the reference voltage vector V is calculated in step S1refGamma axis component V ofγAmplitude m of3And phase
Figure FDA0003143310420000028
The formula of (1) is:
Figure FDA0003143310420000029
4. the overmodulation method according to claim 2, wherein the reference voltage vector V is calculated in step S1refCharacteristic phase difference of
Figure FDA00031433104200000210
The calculation formula is as follows:
Figure FDA00031433104200000211
5. the overmodulation method according to claim 2, wherein the maximum linear modulation degree M of the 3D-SVPWM modulation scheme is calculated in step S2max1And maximum compression modulation degree Mmax2The method specifically comprises the following steps:
defining a function formulaW1，
Figure FDA0003143310420000031
Defining a functional formula W2，
Figure FDA0003143310420000032
Wherein, theta1Has a value range of
Figure FDA0003143310420000033
At theta1Within the value range of (A) calculating the function formula W1Minimum value of W1minCalculating a functional formula W2Minimum value of W2minWhen W is1min≤W2minWhen M is in contact withmax1＝W1minWhen W is1min>W2minWhen M is in contact withmax1＝W2minCalculating a functional curve W1Sum function formula W2The function value of the curve intersection point is Mmax2。
6. The overmodulation method for the 3D-SVPWM modulation strategy with the minimum transient error according to claim 1, wherein the specific way of judging the modulation order number is as follows:
defining the intermediate variables judged by the serial number of the modulation body as a first variable A, a second variable B, a third variable C, a fourth variable N and a fifth variable A1A sixth variable B1The seventh variable C1The eighth variable N1Define the functional formula F1，
Figure FDA0003143310420000034
Definition function formula F2，F2＝2Vγ-VαDefine the functional formula F3，
Figure FDA0003143310420000035
Definition function formula F4，F4＝VβDefine the functional formula F5，
Figure FDA0003143310420000036
Definition function formula F6，
Figure FDA0003143310420000037
Then:
when F is present1When the value is more than or equal to 0, A is 1; when F is present1<When 0, A is 0; when F is present2When the value is more than or equal to 0, B is 1; when F is present2<When 0, B is 0; when F is present3When the carbon content is more than or equal to 0, C is 1; when F is present3<When 0, C is 0; n ═ a +2B + 4C;
when F is present4When the value is more than or equal to 0, A11 is ═ 1; when F is present4<At 0, A10; when F is present5When not less than 0, B11 is ═ 1; when F is present5<At 0, B10; when F is present6When not less than 0, C11 is ═ 1; when F is present6<At 0, C1＝0；N1＝A1+2B1+4C1；
Each value of the fourth variable N corresponds to a modulation entity number, which is as follows: n ═ 5 corresponds to modulator 1; n1 corresponds to modulator 2; n ═ 3 corresponds to the modulator 3; n ═ 2 corresponds to the modulator 4; n ═ 6 corresponds to the modulator 5; n-4 corresponds to the modulator 6; when N is 0, an eighth variable N is required to be combined1Making a further determination of the value, wherein when N is present11 or N1When the value is 3, the value corresponds to the modulation body 2, and when N is14 or N1When the number is 5, the number is N, the modulation body 4 is corresponded12 or N1When it is 6, it corresponds to the modulator 6; when N is 7, an eighth variable N is required to be combined1Making a further determination of the value, wherein when N is present12 or N1When the value is 3, the value corresponds to the modulation body 1, and when N is11 or N1When the number is 5, the number is N, the modulation body 3 is concerned14 or N1When 6, the corresponding modulator 5 is used.
7. The overmodulation method for the 3D-SVPWM modulation strategy with the minimum transient error according to claim 1, wherein the specific way to select the corresponding compression plane constraint equation from the determined modulation order number is as follows:
the compression plane constraint equation of the modulator 1 is:
Figure FDA0003143310420000041
the compression plane constraint equation of the modulation volume 2 is:
Figure FDA0003143310420000042
the compression plane constraint equation of the modulator body 3 is:
Figure FDA0003143310420000043
the compression plane constraint equation of the modulation volume 4 is:
Figure FDA0003143310420000044
the compression plane constraint equation of the modulator 5 is:
Figure FDA0003143310420000045
the compression plane constraint equation for the modulator 6 is:
Figure FDA0003143310420000046
8. a system applied to the overmodulation method of the 3D-SVPWM modulation strategy with minimum transient error according to any one of claims 1 to 7, comprising: first DC source Udc1A second DC source Udc2The three-phase two-level inverter comprises a first three-phase two-level inverter VSI1, a second three-phase two-level inverter VSI2, a three-phase stator winding OEWIM, a neutral line I, a capacitor C1, a capacitor C2, a capacitor C3 and a capacitor C4;
the capacitor C1 and the capacitor C2 are connected in series and then connected to a first direct current source Udc1Between the direct current positive bus P and the direct current negative bus N,the common node of the capacitor C1 and the capacitor C2 is marked as a point O; the capacitor C3 and the capacitor C4 are connected in series and then connected to a second direct current source Udc2Between the positive dc bus P 'and the negative dc bus N', the common node of the capacitors C3 and C4 is denoted as point O ', the neutral line I connects the point O and the point O', and the first dc source Udc1And a second DC source Udc2All direct current voltages are Udc；
In the three-phase bridge arm of the first three-phase two-level inverter VSI1, each phase of bridge arm includes 2 switching tubes with anti-parallel diodes, that is, the first three-phase two-level inverter VSI1 includes 6 switching tubes with anti-parallel diodes in total, and 6 switching tubes are respectively marked as Sn1jWherein n represents the phase sequence, n is a, b, c, j represents the serial number of the switching tube, and j is 1, 2; the three-phase bridge arms of the first three-phase two-level inverter VSI1 are connected in parallel between the direct current positive bus P and the direct current negative bus N, namely a switch tube Sa11、Sb11、Sc11The collectors are connected in parallel and then are connected with a direct current positive bus P and a switching tube Sa12、Sb12、Sc12The emitting electrodes are connected in parallel and then connected with a direct current negative bus N; in the three-phase leg of the first three-phase two-level inverter VSI1, the switching tube Sa11And a switching tube Sa12Series, switch tube Sb11And a switching tube Sb12Series, switch tube Sc11And a switching tube Sc12The connection points of the series connection are respectively marked as three-phase bridge arm middle points a of the first three-phase two-level inverter VSI11、b1、c1；
In the three-phase bridge arm of the second three-phase two-level inverter VSI2, each phase of bridge arm includes 2 switching tubes with anti-parallel diodes, that is, the second three-phase two-level inverter VSI2 includes 6 switching tubes with anti-parallel diodes in total, and 6 switching tubes are respectively marked as Sn2j(ii) a The three-phase bridge arms of the second three-phase two-level inverter VSI2 are connected in parallel between the direct current positive bus P 'and the direct current negative bus N', namely a switch tube Sa21、Sb21、Sc21The collectors are connected in parallel and then connected with a direct current positive bus P', and a switching tube Sa22、Sb22、Sc22The emitting electrodes are connected in parallel and then connected with a direct current negative bus N'; three-phase bridge at a second three-phase two-level inverter VSI2In the arm, a switching tube Sa21And a switching tube Sa22Series, switch tube Sb21And a switching tube Sb22Series, switch tube Sc21And a switching tube Sc22The connection points of the series connection are respectively marked as three-phase bridge arm middle points a of the second three-phase two-level inverter VSI22、b2、c2；
The three-phase stator winding OEWIM comprises three-phase windings, and the left ports of the A-phase winding, the B-phase winding and the C-phase winding are respectively connected with the three-phase bridge arm midpoint a of the first three-phase two-level inverter VSI11、b1、c1The right ports of the A-phase winding, the B-phase winding and the C-phase winding are respectively connected with the three-phase bridge arm midpoint a of the second three-phase two-level inverter VSI22、b2、c2。
CN202110746997.5A 2021-07-01 2021-07-01 Overmodulation method and system for 3D-SVPWM modulation strategy with minimum instantaneous error Active CN113364326B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110746997.5A CN113364326B (en) 2021-07-01 2021-07-01 Overmodulation method and system for 3D-SVPWM modulation strategy with minimum instantaneous error

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110746997.5A CN113364326B (en) 2021-07-01 2021-07-01 Overmodulation method and system for 3D-SVPWM modulation strategy with minimum instantaneous error

Publications (2)

Publication Number Publication Date
CN113364326A true CN113364326A (en) 2021-09-07
CN113364326B CN113364326B (en) 2022-09-16

Family

ID=77537950

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110746997.5A Active CN113364326B (en) 2021-07-01 2021-07-01 Overmodulation method and system for 3D-SVPWM modulation strategy with minimum instantaneous error

Country Status (1)

Country Link
CN (1) CN113364326B (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103107761A (en) * 2013-01-11 2013-05-15 哈尔滨工业大学 Three-dimensional space vector pulse width modulation (SVPWM) method based on four-phrase five-wire topology
US20150311818A1 (en) * 2014-04-23 2015-10-29 National Tsing Hua University Load impedance estimation and repetitive control method capable of allowing inductance variation for inverter
CN107196543A (en) * 2017-07-05 2017-09-22 合肥工业大学 Common DC bus opens winding asynchronous electric system zero sequence circulation inhibition method
CN110995115A (en) * 2019-12-23 2020-04-10 深圳市凌康技术有限公司 Improved three-dimensional space vector modulation method and system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103107761A (en) * 2013-01-11 2013-05-15 哈尔滨工业大学 Three-dimensional space vector pulse width modulation (SVPWM) method based on four-phrase five-wire topology
US20150311818A1 (en) * 2014-04-23 2015-10-29 National Tsing Hua University Load impedance estimation and repetitive control method capable of allowing inductance variation for inverter
CN107196543A (en) * 2017-07-05 2017-09-22 合肥工业大学 Common DC bus opens winding asynchronous electric system zero sequence circulation inhibition method
CN110995115A (en) * 2019-12-23 2020-04-10 深圳市凌康技术有限公司 Improved three-dimensional space vector modulation method and system

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
JOSÉ LUIS MONROY MORALES ET AL.: "A digital control for a Three-Dimensional SV-PWM multilevel converter", 《2014 IEEE INTERNATIONAL AUTUMN MEETING ON POWER, ELECTRONICS AND COMPUTING (ROPEC)》 *
LIN ZHOU ET AL.: "Application of a four-leg ASVG based on", 《PROCEEDINGS. INTERNATIONAL CONFERENCE ON POWER SYSTEM TECHNOLOGY》 *
卢远宏等: "基于空间直角坐标系的逆变器调制波研究", 《电工技术学报》 *
胡慧慧等: "抑制三相四桥臂逆变器共模电压的三维SVPWM控制策略", 《电力系统自动化》 *

Also Published As

Publication number Publication date
CN113364326B (en) 2022-09-16

Similar Documents

Publication Publication Date Title
CN107171313B (en) MMC system simplified electromagnetic transient modeling method considering negative sequence component
CN112234808B (en) Double-frequency ripple suppression circuit and suppression method of single-phase inverter
CN111371337B (en) Neutral point potential balance control method of diode clamping type three-level inverter
CN108809133A (en) A kind of active neutral-point-clamped five-electrical level inverter capacitor voltage balance control method
CN106169879A (en) Revise VIENNA rectifier modulator approach, controller and the system injecting zero-sequence component
CN109980968B (en) Modular multilevel converter, control system and application thereof
CN112448407A (en) Impedance optimization control strategy for improving stability of grid-connected system under constant power control under bidirectional power flow
CN106787895A (en) Parallel three phase inversion system circulation inhibition method based on SVM strategies
CN114337343A (en) Method and device for establishing MMC broadband three-port frequency coupling impedance model
CN113364327B (en) Output harmonic minimization 3D-AZSPWM modulation strategy overmodulation method and system
CN109347335B (en) Modular multilevel converter bridge arm topology suitable for current source control
CN108336932A (en) Double three-phase machine minimum harmonic injection Over-modulation and its carrier wave implementation method
CN112636618B (en) Modulation method for reducing VIENNA rectifier current zero crossing distortion
CN111800026B (en) Space vector modulation strategy of three-phase current type seven-level PWM rectifier
CN113364326B (en) Overmodulation method and system for 3D-SVPWM modulation strategy with minimum instantaneous error
CN113364330B (en) Output harmonic wave minimized 3D-SVPWM modulation strategy overmodulation method and system
CN113364328B (en) Overmodulation output maximization method and system of 3D-SVPWM (three-dimensional-space vector pulse width modulation) strategy
CN113364325B (en) 3D-SVPWM modulation strategy rapid overmodulation method and system
CN113364331B (en) Overmodulation method and system for 3D-AZSPWM modulation strategy with minimum instantaneous error
CN113364332B (en) 3D-AZSPWM modulation strategy rapid overmodulation method and system
CN113364329B (en) Overmodulation output maximization method and system of 3D-AZSPWM modulation strategy
CN110336472A (en) A kind of H3IMC topological structure and its boost control method with unbalanced load
CN112701952B (en) PWM method and system for minimum effective value of current ripple of three-phase two-level inverter
Dehghani et al. Dynamic behavior control of induction motor with STATCOM
CN118174582B (en) Deadbeat predictive control method

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant