CN108712129B - Torque calculation optimization method based on direct torque control prediction control - Google Patents

Torque calculation optimization method based on direct torque control prediction control Download PDF

Info

Publication number
CN108712129B
CN108712129B CN201810638838.1A CN201810638838A CN108712129B CN 108712129 B CN108712129 B CN 108712129B CN 201810638838 A CN201810638838 A CN 201810638838A CN 108712129 B CN108712129 B CN 108712129B
Authority
CN
China
Prior art keywords
torque
stator flux
formula
voltage vector
amplitude
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.)
Expired - Fee Related
Application number
CN201810638838.1A
Other languages
Chinese (zh)
Other versions
CN108712129A (en
Inventor
李耀华
任佳越
杨启东
师浩浩
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.)
Changan University
Original Assignee
Changan University
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 Changan University filed Critical Changan University
Priority to CN201810638838.1A priority Critical patent/CN108712129B/en
Publication of CN108712129A publication Critical patent/CN108712129A/en
Application granted granted Critical
Publication of CN108712129B publication Critical patent/CN108712129B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • H02P21/20—Estimation of torque
    • 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
    • H02P21/30—Direct torque control [DTC] or field acceleration method [FAM]

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Control Of Ac Motors In General (AREA)

Abstract

The invention discloses a torque calculation optimization method based on direct torque control prediction control, which comprises the steps of determining a voltage vector selection area through a stator flux linkage comparator and a torque comparator, dividing the area into four equal parts, inputting a stator flux linkage amplitude and a torque value into a target function to select a minimum value, selecting an interval and an angle of the voltage vector, selecting the voltage vector in the interval given by an interval table and outputting the synthesized voltage vector, obtaining the stator flux linkage amplitude according to a stator flux linkage change diagram, determining a torque formula through the stator flux linkage amplitude, optimizing the torque formula, and verifying the feasibility of the torque formula through the relative error of a traditional torque formula and an optimized torque formula. The optimized torque formula can replace the traditional torque formula so as to improve the performance of a direct torque control system of the permanent magnet synchronous motor, reduce torque pulsation and stabilize switching frequency.

Description

Torque calculation optimization method based on direct torque control prediction control
Technical Field
The invention belongs to the technical field of voltage vector modulation, and particularly relates to a torque calculation optimization method based on direct torque control prediction control.
Background
The direct torque control technology is based on a stator flux linkage coordinate system and directly takes the torque as a control object, so that a large amount of calculation and dependency on motor parameters during rotation coordinate transformation are avoided, the dynamic performance is good, and the torque response time is short.
In a direct torque control system of a permanent magnet synchronous motor realized by a traditional switch meter, a voltage vector is continuously applied in a sampling period, and the increase and decrease of actual torque exceed expected requirements, so that overshoot pulsation is caused.
In order to solve the problems, prediction control is introduced, an evaluation function is introduced, the torque error and the stator flux linkage error are comprehensively considered and controlled, and a space vector modulation technology is adopted, so that a more ideal control effect is realized.
However, along with the variable and the operation function, the time and the complexity of calculation operation are increased, so that a torque calculation optimization method for DTC prediction control is provided, and further the control performance is optimized.
Disclosure of Invention
The technical problem to be solved by the present invention is to provide a torque calculation optimization method based on direct torque control predictive control to improve the performance of a direct torque control system of a permanent magnet synchronous motor, reduce torque ripple, and make the switching frequency constant, aiming at the defects in the prior art.
The invention adopts the following technical scheme:
a torque calculation optimization method based on direct torque control prediction control comprises the steps of determining a voltage vector selection area through a stator flux linkage comparator and a torque comparator, dividing the area into four equal parts, inputting a stator flux linkage amplitude value and a torque value into a target function g to select min (g), selecting an interval and an angle of a voltage vector, selecting the voltage vector in an interval given by an interval table and outputting a synthesized voltage vector
Figure GDA0002437290980000021
Obtaining a stator flux linkage amplitude according to a stator flux linkage change diagram, determining a torque formula through the stator flux linkage amplitude, optimizing, and verifying the feasibility of the stator flux linkage amplitude through the relative error of a traditional torque formula and an optimized torque formula.
Specifically, according to the action of the voltage vector on the flux linkage and the idea of predictive control, neglecting the resistance voltage drop of the stator, after the voltage vector is applied, determining the relationship between the torque value k +1 of the traditional model at the next moment and the torque angle and the amplitude of the stator flux linkage at the next moment, and obtaining the value delta (k +1) of the torque angle and the amplitude of the stator flux linkage at the next moment
Figure GDA0002437290980000022
According to the value delta (k +1) of the torque angle at the next moment and the amplitude of the stator flux linkage at the next moment
Figure GDA00024372909800000211
Determining the optimized torque T at the next time k +1e′(k+1)。
Further, define
Figure GDA0002437290980000023
Optimized torque equation T for the next time k +1e' (k +1) is as follows:
Figure GDA0002437290980000024
wherein p is the number of polar pairs, LdIs d-axis inductance,. psifAs the amplitude of the flux linkage of the rotor,
Figure GDA0002437290980000025
the amplitude of the stator flux linkage at the next moment, alpha is the included angle between the voltage vector and the stator flux linkage, delta (k) is the torque angle at the current moment,
Figure GDA0002437290980000026
the stator flux linkage amplitude at the current time,
Figure GDA0002437290980000027
for the resultant voltage vector, Δ t is the time over which the voltage vector acts.
Further, the value δ (k +1) of the torque angle at the next time is as follows:
Figure GDA0002437290980000028
further, the stator flux linkage amplitude at the next moment
Figure GDA0002437290980000029
The following were used:
Figure GDA00024372909800000210
further, a relative error rate η of the optimized torque formula and the traditional torque formula is obtained according to the torque absolute error formula, and the feasibility of the optimized torque formula is verified through the relative error rate between the traditional torque formula and the optimized torque formula.
further, the relative error rate η is as follows:
Figure GDA0002437290980000031
compared with the prior art, the invention has at least the following beneficial effects:
the invention relates to a torque calculation optimization method based on direct torque control predictive control, which comprises the steps of firstly providing a traditional torque calculation formula, then carrying out a series of optimization on the traditional torque theoretical formula, calculating the relative error between the optimized expression and the traditional calculation formula, analyzing the static and dynamic performance change, verifying the feasibility of a scheme, enabling the calculation process to be simpler and more convenient, and reducing the operation times.
Furthermore, the formula of the torque angle at the next moment is used for writing a formula of the traditional torque at the next moment, then comparison after optimization is carried out, and the formula of the stator flux amplitude at the next moment is used for writing a formula of the traditional torque at the next moment, comparison is carried out, and the formula of the traditional torque at the next moment is written according to the formula of the torque angle and the stator flux amplitude, and can be compared with the formula of the optimized torque.
Further, according to the traditional torque formula at the next moment, writing the torque formula at the next moment after optimization, and comparing the relative errors of the torque formula and the torque formula to verify the feasibility of the torque formula.
In conclusion, the torque formula optimized by the method can replace the traditional torque formula, and the feasibility is reliable.
The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.
Drawings
Fig. 1 is a schematic block diagram of a permanent magnet synchronous motor direct torque control based on the present invention;
FIG. 2 is a functional block diagram of the present invention;
FIG. 3 is a diagram showing the variation of the stator flux linkage in the present invention;
FIG. 4 is an overall view of torque versus error;
FIG. 5 is an X-Z view of torque versus error;
FIG. 6 is a Y-Z view of torque versus error;
FIG. 7 is a predicted control torque response plot when the torque calculation method is not optimized;
FIG. 8 is a predicted control torque response graph after optimization of the torque calculation method.
Detailed Description
The invention discloses a torque calculation optimization method based on direct torque control prediction control, which selects voltage vectors in intervals given by an interval table and outputs the synthesized voltage vectors by selecting intervals and angles of the voltage vectors
Figure GDA0002437290980000048
According to the stator flux linkage change diagram, a formula of the stator flux linkage amplitude can be written out, and finally a traditional torque formula is obtained. The invention provides an optimized torque formula based on DTC prediction control, and the feasibility of the scheme is verified by comparing relative errors of the two. The invention can optimize the torque calculation method and has certain feasibility.
Referring to fig. 1, a voltage vector selection region is determined by a stator flux comparator and a torque comparator, a g value of a target function is calculated by a stator flux amplitude and a torque value, an optimal g value is selected, and an optimal voltage vector is selected
Figure GDA0002437290980000041
Thereby writing a torque equation.
Referring to fig. 2, according to the torque calculation optimization method based on direct torque control prediction control of the present invention, first, a voltage vector is determined
Figure GDA0002437290980000042
Value output by flux-linkage hysteresis comparator
Figure GDA0002437290980000043
The method comprises the steps of selecting an interval in which a voltage vector is positioned according to a value tau output by a torque hysteresis comparator, dividing the interval into four intervals, inputting a stator flux linkage amplitude and a torque value into a target function g, selecting min (g), finding out the voltage vector at a corresponding angle, and adopting the concrete steps ofThe following were used:
s1, determining a traditional torque calculation torque formula based on DTC prediction control;
selecting the minimum value min (g) of g through the graphs of fig. 1 and 2, finding out the corresponding voltage vector angle, and synthesizing the required voltage vector
Figure GDA0002437290980000044
Voltage vector
Figure GDA0002437290980000045
The amplitude of the stator flux linkage can be found and the torque value can be found for the stator flux linkage amplitude. Voltage vector
Figure GDA0002437290980000046
Changes in the direction and magnitude of the voltage vector with time, so that the torque calculation method, the voltage vector, is optimized
Figure GDA0002437290980000047
Must be found.
According to the voltage vector acting on the flux linkage, and the idea of predictive control, a calculation expression of the torque corresponding to the next time (k +1) is listed first.
Neglecting the stator resistance drop, the torque values after applying the voltage vector are as follows.
The relationship between the torque value at the next moment, the torque angle at the next moment and the stator flux amplitude at the next moment in the conventional model is shown as the following formula (1):
Figure GDA0002437290980000051
the stator flux linkage amplitude at the next moment is as shown in equation (2):
Figure GDA0002437290980000052
definition ofqAs shown in formula (3):
Figure GDA0002437290980000053
the value of the torque angle at the next time is as follows in equation (4):
Figure GDA0002437290980000054
fig. 3 is a diagram of the stator flux linkage change after the voltage vector acts for Δ t time, and the amplitude of the stator flux linkage at the next time is calculated through fig. 3, so that a predicted torque value at the next time can be written, and the value of the stator flux linkage amplitude at the next time is expressed by the following formula (10):
Figure GDA0002437290980000055
the torque value at the next moment of the conventional model can be written again as the following equation (5):
Figure GDA0002437290980000056
s2, optimizing a traditional torque theoretical formula;
after listing the torque at the next time (k +1), the expression is optimized, and the optimized torque expression is defined as shown in the formula (6):
Figure GDA0002437290980000057
and S3, calculating the relative error between the optimized expression and the traditional calculation formula, analyzing the static and dynamic performance change, and verifying the feasibility of the scheme.
And calculating the relative error rate of the optimized expression and the traditional expression, and analyzing the static and dynamic performance change of the expression.
the relative error rate η defining equations (6) and (5) is as shown in equations (7) and (8):
Figure GDA0002437290980000062
Figure GDA0002437290980000061
referring to fig. 4, 5 and 6, it can be seen from the relative error of the torque:
since the relative error rate between the two is at most + -1%, and the torque ripple values before and after simplification of the torque calculation method are 0.3107N · m and 0.3098N · m, respectively, T can be used approximately in the prediction controle' (k +1) substituted for Te(k+1)。
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 drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. 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.
Referring to fig. 4, there is shown an overall view of torque relative error, which is not very large from an overall view, illustrating the feasibility of the solution.
Referring to FIG. 5, there is shown an X-Z view of the relative error of torque, which is at most + -1% when viewed from the figure, illustrating that a conventional torque equation may be substituted for the optimized torque equation.
Referring to FIG. 6, there is shown a Y-Z view of the relative error of torque, which is feasible as the torque angle increases, and the relative error becomes smaller.
Referring to FIG. 7, a predicted control torque response plot for a torque calculation method that is not optimized is shown for comparison with an optimized torque plot.
Referring to fig. 8, which is a predicted control torque response graph after the torque calculation method is optimized, compared with fig. 7, it is found that the torque has no large fluctuation, and the scheme is feasible from the static viewpoint.
The above-mentioned contents are only for illustrating the technical idea of the present invention, and the protection scope of the present invention is not limited thereby, and any modification made on the basis of the technical idea of the present invention falls within the protection scope of the claims of the present invention.

Claims (3)

1. A torque calculation optimization method based on direct torque control prediction control is characterized in that a voltage vector selection area is determined through a stator flux linkage comparator and a torque comparator, the area is divided into four equal parts, a stator flux linkage amplitude value and a torque value are input into a target function g to be selected and taken out for min (g), the interval and the angle of a voltage vector are selected, the voltage vector is selected in an interval given by an interval table, and the synthesized voltage vector is output
Figure FDA0002277368960000011
Obtaining a stator flux amplitude according to a stator flux change diagram, determining a torque formula through the stator flux amplitude, optimizing the torque formula, verifying the feasibility of the stator flux amplitude through relative errors of a traditional torque formula and an optimized torque formula, neglecting the resistance voltage drop of a stator according to the action of a voltage vector on flux and the idea of predictive control, determining the relationship between a torque value k +1 at the next moment of a traditional model and a torque angle and the stator flux amplitude at the next moment after applying the voltage vector, and obtaining a value delta (k +1) of the torque angle at the next moment and the stator flux amplitude at the next moment
Figure FDA0002277368960000012
According to the value delta (k +1) of the torque angle at the next moment and the amplitude of the stator flux linkage at the next moment
Figure FDA0002277368960000013
Determining the optimized torque T at the next time k +1e' (k +1) definition
Figure FDA0002277368960000014
Optimized torque equation T for the next time k +1e' (k +1) is as follows:
Figure FDA0002277368960000015
wherein p is the number of polar pairs, LdIs d-axis inductance,. psifAs the amplitude of the flux linkage of the rotor,
Figure FDA0002277368960000016
the amplitude of the stator flux linkage at the next moment, alpha is the included angle between the voltage vector and the stator flux linkage, delta (k) is the torque angle at the current moment,
Figure FDA0002277368960000017
the stator flux linkage amplitude at the current time,
Figure FDA0002277368960000018
for the resultant voltage vector, Δ t is the time over which the voltage vector acts;
the relationship between the torque value at the next moment and the torque angle and the stator flux amplitude at the next moment in the conventional model is as follows:
Figure FDA0002277368960000019
the value δ (k +1) of the torque angle at the next time is as follows:
Figure FDA00022773689600000110
stator flux linkage amplitude at next moment
Figure FDA00022773689600000111
The following were used:
Figure FDA00022773689600000112
Figure FDA0002277368960000021
the torque value at the next moment of the conventional model can be written again as:
Figure FDA0002277368960000022
2. a torque calculation optimization method based on direct torque control predictive control according to claim 1, characterized in that the relative error rate η between the optimized torque formula and the conventional torque formula is obtained from the torque absolute error formula, and the feasibility of the optimized torque formula is verified by the relative error rate between the conventional torque formula and the optimized torque formula.
3. a torque calculation optimization method based on direct torque control prediction control according to claim 2, characterized by the following relative error rate η:
Figure FDA0002277368960000023
CN201810638838.1A 2018-06-20 2018-06-20 Torque calculation optimization method based on direct torque control prediction control Expired - Fee Related CN108712129B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810638838.1A CN108712129B (en) 2018-06-20 2018-06-20 Torque calculation optimization method based on direct torque control prediction control

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810638838.1A CN108712129B (en) 2018-06-20 2018-06-20 Torque calculation optimization method based on direct torque control prediction control

Publications (2)

Publication Number Publication Date
CN108712129A CN108712129A (en) 2018-10-26
CN108712129B true CN108712129B (en) 2020-05-19

Family

ID=63871812

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810638838.1A Expired - Fee Related CN108712129B (en) 2018-06-20 2018-06-20 Torque calculation optimization method based on direct torque control prediction control

Country Status (1)

Country Link
CN (1) CN108712129B (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103259486A (en) * 2013-05-07 2013-08-21 上海大学 Model prediction three-level direct torque control method based on state trajectory extrapolation
CN103684169A (en) * 2013-11-19 2014-03-26 西安交通大学 Dead-beat based direct torque control method for permanent magnet synchronous motor

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010226777A (en) * 2009-03-19 2010-10-07 Oki Semiconductor Co Ltd Brushless motor driving apparatus

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103259486A (en) * 2013-05-07 2013-08-21 上海大学 Model prediction three-level direct torque control method based on state trajectory extrapolation
CN103684169A (en) * 2013-11-19 2014-03-26 西安交通大学 Dead-beat based direct torque control method for permanent magnet synchronous motor

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
新能源汽车永磁同步电机直接转矩控制电压矢量选择策略研究;焦森;《CNKI》;20180315;参见第4-5章，图5.1、5.3 *

Also Published As

Publication number Publication date
CN108712129A (en) 2018-10-26

Similar Documents

Publication Publication Date Title
CN108649855B (en) Model prediction torque control method based on duty ratio
CN113659898B (en) Model predictive torque control method for double three-phase permanent magnet synchronous motor
JP5447466B2 (en) Rotating machine control device
CN105790664B (en) Permanent magnet synchronous motor model predictive control method
CN108011555B (en) Permanent magnet synchronous motor model prediction current control method
CN110649854A (en) Surface-mounted permanent magnet synchronous motor continuum model prediction torque control method
JP5589556B2 (en) Rotating machine control device
JP2005253258A (en) Controller for winding field type synchronizer
CN113992098A (en) Method and system for improving steady-state performance of permanent magnet synchronous motor
CN108712129B (en) Torque calculation optimization method based on direct torque control prediction control
CN113206625A (en) Maximum torque current ratio control method for built-in permanent magnet synchronous motor
CN108718168B (en) Torque calculation simplification method for DTC prediction control
CN117277878A (en) Motor load starting control method based on phase angle compensation
CN110707980A (en) Fitting method for MTPA control curve of permanent magnet synchronous motor
JP5724737B2 (en) Rotating machine control device
CN114294461B (en) Construction method of control system of intelligent valve electric actuating mechanism
CN116317792A (en) Permanent magnet synchronous motor prediction current control method and system considering parameter mismatch
CN106953575B (en) A kind of Direct Torque Control and device of iterative learning
JP5678837B2 (en) Rotating machine control device
CN110336510B (en) Motor control method and system and household appliance
CN113824364A (en) Method, system, equipment and medium for flux weakening control of permanent magnet synchronous motor
CN108988727B (en) Magnetic linkage calculation simplification method for DTC prediction control
CN111800057B (en) Predictive control method and system for permanent magnet synchronous motor
CN115133832B (en) Real-time parameter correction method for surface-mounted permanent magnet synchronous motor
CN109004876B (en) Torque angle simplified calculation method based on DTC prediction control

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
CF01 Termination of patent right due to non-payment of annual fee
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20200519

Termination date: 20210620