CN112019128A

CN112019128A - Duty ratio determination method and device in SVPWM control

Info

Publication number: CN112019128A
Application number: CN201910468742.XA
Authority: CN
Inventors: 马东辉; 汪运浩
Original assignee: Beijing CHJ Automobile Technology Co Ltd
Current assignee: Beijing CHJ Automobile Technology Co Ltd
Priority date: 2019-05-31
Filing date: 2019-05-31
Publication date: 2020-12-01

Abstract

The embodiment of the disclosure discloses a duty ratio determining method and device in SVPWM control, relates to the technical field of motor control, and mainly aims to simplify the duty ratio determining process in SVPWM control. The main technical scheme of the embodiment of the disclosure comprises the following steps: determining a component U of a reference voltage on a horizontal axis of orthogonal axes_αAnd determining the component U of the reference voltage on the vertical axis among the orthogonal axes_β(ii) a According to U_α、U_βAnd DC bus voltage U_dcDetermining an intermediate variable Y, Z; according to U_α、U_βY and Z, determining the sector where the reference voltage is located; according to the sector, the Y and the Z, selecting a duty ratio expression corresponding to the sector from preset duty ratio expressions, and determining a duty ratio based on the selected duty ratio expression; the preset duty ratio expression is set based on expressions of intermediate variables Y and Z.

Description

Duty ratio determination method and device in SVPWM control

Technical Field

The embodiment of the disclosure relates to the technical field of motor control, in particular to a duty ratio determining method and device in SVPWM control.

Background

In devices requiring a power inverter function, such as motor control and switching power supplies, SVPWM control has become the most widely used control method because of its advantage of improving the utilization efficiency of a dc power supply.

Currently, the method for determining the duty ratio in SVPWM control generally includes: first determining U by using reference voltage_ref1、U_ref2、U_ref3Sign of three intermediate variables, and according to U_ref1、U_ref2、U_ref3The three intermediate variable signs determine the value of the intermediate variable A, B, C. And calculating the value of an algebraic expression N-4C +2B + A according to the value of the intermediate variable A, B, C, and determining the sector based on the preset corresponding relation between N and the sector. After sector determination, expression according to intermediate variables

Intermediate variables X, Y, Z are calculated. Finally, the duty cycle is determined based on X, Y, Z, the sector. As can be seen, in the conventional method, the sector judgment involves various intermediate variables, and the calculation is complex, and the intermediate variables used in the sector judgment process and the duty ratio calculation both involve the control period of the SVPWM, and the calculation amount is large, so the process of determining the duty ratio in the SVPWM control is complex.

Disclosure of Invention

In view of this, embodiments of the present disclosure provide a method and an apparatus for determining a duty ratio in SVPWM control, and mainly aim to simplify a process of determining a duty ratio in SVPWM control. The embodiment of the disclosure mainly provides the following technical scheme:

in a first aspect, an embodiment of the present disclosure provides a method for determining a duty ratio in SVPWM control, where the method includes:

determining a component U of a reference voltage on a horizontal axis of orthogonal axes_αAnd determining the component U of the reference voltage on the vertical axis among the orthogonal axes_β；

According to U_α、U_βAnd DC bus voltage U_dcDetermining an intermediate variable Y, Z;

according to U_α、U_βY and Z, determining the sector in which the reference voltage is located；

According to the sector, Y and Z, selecting a duty ratio expression corresponding to the sector from preset duty ratio expressions, and determining the duty ratio based on the selected duty ratio expression; the preset duty ratio expression is set based on expressions of intermediate variables Y and Z.

In a second aspect, an embodiment of the present disclosure provides a duty ratio determining apparatus in SVPWM control, the apparatus including:

a first determination unit for determining components U of the reference voltage on horizontal and vertical axes among the orthogonal axes, respectively_α、U_β；

A second determination unit for determining the basis of U_α、U_βAnd DC bus voltage U_dcDetermining an intermediate variable Y, Z; a third determination unit for determining the value according to U_α、U_βY and Z, determining the sector where the reference voltage is located;

a fourth determining unit, configured to select, according to the sector, Y, and Z, a duty ratio expression corresponding to the sector from preset duty ratio expressions, and determine a duty ratio based on the selected duty ratio expression; the preset duty ratio expression is set based on the expression of the intermediate variable.

In a third aspect, an embodiment of the present disclosure provides a storage medium, where the storage medium includes a stored program, and when the program runs, a device in which the storage medium is controlled to execute the method for determining a duty ratio in SVPWM control according to the first aspect.

In a fourth aspect, embodiments of the present disclosure provide a human-computer interaction device, which includes a storage medium; and one or more processors, the storage medium coupled with the processors, the processors configured to execute program instructions stored in the storage medium; the program instructions are executed to execute the duty ratio determination method in the SVPWM control according to the first aspect.

With the above technical solution, the method and the device for determining the duty ratio in the SVPWM control provided by the embodiments of the present disclosure firstly determine the reference voltages respectively in the middle level and the middle level of the quadrature axisComponent U on the axis and vertical axis_α、U_βAnd according to U_α、U_βAnd DC bus voltage U_dcThe intermediate variable Y, Z is determined. Then according to U_α、U_βAnd Y and Z, determining the sector where the reference voltage is located, and finally selecting a duty ratio expression corresponding to the sector from a preset duty ratio expression to determine the duty ratio according to the determined sector, Y and Z. Therefore, the judgment of the sector where the reference voltage is located is simple and easy to understand, intermediate variables used in the judgment process of the sector and the calculation of the duty ratio do not relate to the control period of the SVPWM, the calculation amount is small, and the determination process of the duty ratio in the SVPWM control is greatly simplified.

The foregoing description is only an overview of the embodiments of the present disclosure, and in order to make the technical means of the embodiments of the present disclosure more clearly understood, the embodiments of the present disclosure may be implemented in accordance with the content of the description, and in order to make the foregoing and other objects, features, and advantages of the embodiments of the present disclosure more clearly understood, the following detailed description of the embodiments of the present disclosure is given.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the embodiments of the present disclosure. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

fig. 1 shows a flowchart of a duty ratio determination method in SVPWM control according to an embodiment of the present disclosure;

FIG. 2 illustrates an exemplary diagram of a sector provided by an embodiment of the present disclosure;

fig. 3 illustrates a flow chart of sector determination provided by an embodiment of the present disclosure;

fig. 4 shows a block diagram of a duty ratio determining apparatus in SVPWM control according to an embodiment of the present disclosure;

fig. 5 shows a block diagram of another SVPWM control duty ratio determining apparatus provided in the embodiment of the present disclosure.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

In a first aspect, an embodiment of the present disclosure provides a method for determining a duty ratio in SVPWM control, as shown in fig. 1, the method mainly includes:

101. determining a component U of a reference voltage on a horizontal axis of orthogonal axes_αAnd determining the component U of the reference voltage on the vertical axis among the orthogonal axes_β。

In practical application, the orthogonal axis is a two-phase static coordinate system formed by orthogonal horizontal and vertical axes. Among the orthogonal axes, the horizontal axis is an α axis, and the vertical axis is a β axis. In determining a voltage as an input to the motor, the voltage is taken as a reference voltage, and components of the reference voltage on the α axis and the β axis, respectively, are determined based on a voltage vector of the reference voltage. Unambiguous determination of U based on a reference voltage_α、U_βPositive and negative signs of (c).

102. According to U_α、U_βAnd DC bus voltage U_dcThe intermediate variable Y, Z is determined.

Specifically, in the conventional method, the intermediate variables Y and Z used for determining the duty ratio are expressed as:

wherein, T_SAnd characterizing the control period of the SVPWM. Considering that the magnitude of the duty ratio is not related to the control period of SVPWM, in order to simplify the determination process of the duty ratio, the expression of the intermediate variable is determined in the embodiment of the present disclosure as follows:

specifically, U is determined_αAnd U_βThen, the DC bus voltage U of the motor is obtained_dcWill U is_α、U_βAnd U_dcSubstituting into the expression for intermediate variable Y, Z, intermediate variable Y, Z is calculated.

103. According to U_α、U_βY and Z, determining the sector in which the reference voltage is located.

Specifically, in an orthogonal axis coordinate system composed of an axis α on the horizontal axis and an axis β on the vertical axis, there are 6 sectors "sector 1, sector 2, sector 3, sector 4, sector 5, and sector 6" as shown in fig. 2. It can be seen from fig. 2 that each sector corresponds to a 60 deg. region.

Following according to U_α、U_βY and Z, the process of determining the sector in which the reference voltage is located is explained:

first, assuming that the reference voltage vector falls in each sector, respectively, the essential condition that the reference voltage vector falls in a different sector is determined.

Specifically, U is assumed to fall within the first sector_α>0、U_β>0. Determining based on a tangent function

The essential conditions for determining that the reference voltage vector falls in the first sector are: u shape_α>0、U_β>0、

Specifically, assume that the reference voltage vector falls in the second sector, at U_α>0、U_β>At 0, based on the tangent function, determine

So that the reference voltage vector is determined to fall in the second sectorThe following conditions are required: u shape_α>0、U_β>0、

At U_α＜0、U_β>At 0, based on the tangent function, determine

Therefore, the essential condition for determining that the reference voltage vector falls in the second sector is: u shape_α＜0、U_β>0、

Specifically, U is assumed to fall within the third sector_α＜0、U_β>0, determining based on the tangent function

Therefore, the essential condition for determining that the reference voltage vector falls in the third sector is: u shape_α＜0、U_β>0、

Specifically, assuming the reference voltage vector falls in the fourth sector, U_α＜0、U_β< 0, determining based on the tangent function

Therefore, the essential condition for determining that the reference voltage vector falls in the fourth sector is: u shape_α＜0、U_β＜0、

Specifically, assume that the reference voltage vector falls in the fifth sector, at U_α>0、U_βWhen < 0, based on the tangent function, determine

So that it is determined that the reference voltage vector falls onThe requirements of the five sectors are as follows: u shape_α>0、U_β＜0、

At U_α＜0、U_βWhen < 0, based on the tangent function, determine

Therefore, the essential condition for determining that the reference voltage vector falls in the second sector is: u shape_α＜0、U_β＜0、

Specifically, assuming the reference voltage vector falls in the sixth sector, U_α＞0、U_β< 0, determining based on the tangent function

Therefore, the essential condition for determining that the reference voltage vector falls in the fourth sector is: u shape_α＞0、U_β＜0、

Secondly, according to the corresponding essential conditions of each sector and the expression of the intermediate variable

And

determining sector judgment requisites for each sector.

Specifically, determining the sector judgment requirement of the first sector is as follows: u shape_α>0、U_β>0、Z<0。

Specifically, determining the sector judgment requirement of the second sector is as follows: u shape_α>0、U_β>0. Z > 0, orU_α＜0、U_β>0、Y＞0。

Specifically, determining the sector judgment requirement of the third sector is as follows: u shape_α＜0、U_β>0、Y<0。

Specifically, determining the sector judgment requirement of the fourth sector is as follows: u shape_α＜0、U_β＜0、Z＞0。

Specifically, determining the sector judgment requirement of the fifth sector is as follows: u shape_α＜0、U_β< 0, Z < 0, or U_α＞0、U_β＜0、Z＜0。

Specifically, determining the sector judgment requirement of the sixth sector is as follows: u shape_α＞0、U_β＜0、Y＞0。

Finally, after determining U_α、U_βAnd after Y and Z, determining the sector where the reference voltage is located according to the sector judgment requirement corresponding to each sector.

104. According to the sector, the Y and the Z, selecting a duty ratio expression corresponding to the sector from preset duty ratio expressions, and determining a duty ratio based on the selected duty ratio expression; the preset duty ratio expression is set based on expressions of intermediate variables Y and Z.

Specifically, the intermediate variable further includes X, and the expression of X is:

the expression of the intermediate variable X is based on the expression of the intermediate variable X in the prior art in consideration of the fact that the size of the duty ratio is not related to the control period of the SVPWM

And (4) obtaining the product. It should be noted that, in the embodiment of the present disclosure, the following relationship exists between the intermediate variables X, Y, Z: x ═ Y + Z.

Specifically, when the duty ratio is determined, it is necessary to determine the duty ratios corresponding to the linear modulation and the overmodulation, respectively, and therefore, the preset duty ratio expression includes a duty ratio expression of the linear modulation and a duty ratio expression of the overmodulation.

Specifically, in the conventional scheme, the duty ratio expressions of linear modulation and overmodulation in each sector are shown in table-1 below.

TABLE-1

Specifically, considering that the magnitude of the duty ratio is not related to the control period of the SVPWM, the preset linear modulation and overmodulation duty ratio expressions for each sector are determined based on the relationship "X ═ Y + Z" between the intermediate variables X, Y, Z, the duty ratio expression for the linear modulation in the conventional system, and the duty ratio expression for the overmodulation in the conventional system, as shown in table-2 below.

TABLE-2

Specifically, after the sector is determined, a linear modulation duty ratio expression and an overmodulation duty ratio expression corresponding to the sector are selected from preset duty ratio expressions shown in table-2. And (5) adaptively substituting Y, Z and X into the selected duty ratio expression to determine the duty ratio.

According to the duty ratio determining method in SVPWM control provided by the embodiment of the disclosure, firstly, the components U of the reference voltage on the horizontal axis and the vertical axis in the orthogonal axes are determined_α、U_βAnd according to U_α、U_βAnd DC bus voltage U_dcThe intermediate variable Y, Z is determined. Then according to U_α、U_βAnd Y and Z, determining the sector where the reference voltage is located, and finally selecting a duty ratio expression corresponding to the sector from a preset duty ratio expression to determine the duty ratio according to the determined sector, Y and Z. Therefore, the judgment of the sector where the reference voltage is located is simple and easy to understand, intermediate variables used in the judgment process of the sector and the calculation of the duty ratio do not relate to the control period of the SVPWM, and the calculated amount is small, so that the method and the device are suitable for the sector where the reference voltage is locatedThe duty ratio determination process in the SVPWM control is greatly simplified.

In one embodiment of the present disclosure, step 103 referred to above in fig. 1 is described as follows:

specifically, step 103 is based on U_α、U_βY and Z, the specific step of determining the sector in which the reference voltage is located comprises: judge U_βWhether greater than 0; if yes, according to U_αY and Z determine the sector in which the reference voltage is located among sector 1, sector 2 and sector 3; otherwise, according to U_αY and Z determine the sector in which the reference voltage is located among sector 4, sector 5 and sector 6.

Specifically, it can be seen from fig. 2 that the α axis explicitly divides the 6 sectors into two groups, sector 1, sector 2 and sector 3, U_βGreater than 0, U for sector 4, sector 5, and sector 6_βLess than 0. Therefore, in order to determine the sector where the reference voltage is located more clearly and quickly, the judgment U needs to be determined first_βWhether greater than 0.

Specifically, in U_βGreater than 0, the sector in which the reference voltage is located is determined among sector 1, sector 2, and sector 3. The specific judgment process is as follows: if U is_αIf Z is greater than 0 and less than 0, determining the sector 1 as the sector where the reference voltage is located; if U is_αIf Y is less than 0 and Y is less than 0, determining sector 3 as the sector where the reference voltage is located; if U is_αIf Z is greater than 0 and Z is greater than 0, determining the sector 2 as the sector where the reference voltage is located; if U is_αLess than 0 and Y greater than 0, sector 2 is determined to be the sector in which the reference voltage is located.

Specifically, in U_βLess than 0, the sector in which the reference voltage is located is determined among sector 4, sector 5, and sector 6. The specific judgment process is as follows: if U is_αIf Z is less than 0 and Z is greater than 0, determining sector 4 as the sector where the reference voltage is located; if U is_αIf Y is greater than 0 and Y is greater than 0, determining the sector 6 as the sector where the reference voltage is located; if U is_αIf Z is less than 0 and Z is less than 0, determining the sector 5 as the sector where the reference voltage is located; if U is_αIs greater than0. And Y is less than 0, sector 5 is determined to be the sector in which the reference voltage is located.

It should be noted that, since there is a case where the reference voltage vector falls on the α axis or the β axis, in order to quickly determine the sector where the reference voltage vector is located in this special case, the following process may be performed: if U is_βEqual to 0, and U_αIf it is greater than 0, then sector 1 or sector 6 is determined as the sector where the reference voltage is located, which may be randomly selected from sector 1 and sector 6. If U is_βEqual to 0, and U_αLess than 0, sector 3 or sector 4 is determined as the sector where the reference voltage is located, which may be randomly selected among sectors 3 and 4. If U is_αEqual to 0, and U_βIf the voltage is greater than 0, determining the sector 2 as the sector where the reference voltage is located; if U is_αEqual to 0, and U_βLess than 0, sector 5 is determined to be the sector in which the reference voltage is located.

For clarity, the process of determining the sector in which the reference voltage is located is described in detail with reference to fig. 3.

In a second aspect, according to the method shown in fig. 1, another embodiment of the present disclosure further provides a method for determining a duty ratio in SVPWM control, as shown in fig. 4, the apparatus mainly includes:

a first determination unit 31 for determining a component U of the reference voltage on a horizontal axis among the orthogonal axes_αAnd determining the component U of the reference voltage on the vertical axis among the orthogonal axes_β；

A second determination unit 32 for determining the basis of U_α、U_βAnd DC bus voltage U_dcDetermining an intermediate variable Y, Z;

a third determination unit 33 for determining the basis of U_α、U_βY and Z, determining the sector where the reference voltage is located;

a fourth determining unit 34, configured to select, according to the sector, Y, and Z, a duty ratio expression corresponding to the sector from preset duty ratio expressions, and determine a duty ratio based on the selected duty ratio expression; the preset duty ratio expression is set based on expressions of intermediate variables Y and Z.

The duty ratio determining device in SVPWM control provided by the embodiment of the disclosure firstly determines the components U of the reference voltage on the horizontal axis and the vertical axis in the orthogonal axis respectively_α、U_βAnd according to U_α、U_βAnd DC bus voltage U_dcThe intermediate variable Y, Z is determined. Then according to U_α、U_βAnd Y and Z, determining the sector where the reference voltage is located, and finally selecting a duty ratio expression corresponding to the sector from a preset duty ratio expression to determine the duty ratio according to the determined sector, Y and Z. Therefore, the judgment of the sector where the reference voltage is located is simple and easy to understand, intermediate variables used in the judgment process of the sector and the calculation of the duty ratio do not relate to the control period of the SVPWM, the calculation amount is small, and the determination process of the duty ratio in the SVPWM control is greatly simplified.

In some embodiments, as shown in fig. 5, the third determining unit 33 includes:

a judging module 331 for judging U_βWhether greater than 0; if yes, trigger the first determining module 332; otherwise, the second determination module 333 is triggered;

the first determining module 332 is configured to determine the position according to U under the trigger of the determining module 331_αY and Z determine the sector in which the reference voltage is located among sector 1, sector 2 and sector 3;

the second determining module 333 is configured to determine, according to U, the trigger of the determining module 331_αY and Z determine the sector in which the reference voltage is located among sector 4, sector 5 and sector 6.

In some embodiments, as shown in fig. 5, the first determining module 332 is configured to determine if U_αIf Z is greater than 0 and less than 0, determining the sector 1 as the sector where the reference voltage is located; if U is_αIf Y is less than 0 and Y is less than 0, determining sector 3 as the sector where the reference voltage is located; if U is_αIf Z is greater than 0 and Z is greater than 0, determining the sector 2 as the sector where the reference voltage is located; if U is_αLess than 0 and Y is greater than 0, sector 2 is determined to be saidThe sector in which the reference voltage is located.

In some embodiments, as shown in fig. 5, the second determining module 333 is configured to determine if U_αIf Z is less than 0 and Z is greater than 0, determining sector 4 as the sector where the reference voltage is located; if U is_αIf Y is greater than 0 and Y is greater than 0, determining the sector 6 as the sector where the reference voltage is located; if U is_αIf Z is less than 0 and Z is less than 0, determining the sector 5 as the sector where the reference voltage is located; if U is_αGreater than 0 and Y less than 0, sector 5 is determined to be the sector in which the reference voltage is located.

a third determining module 334 for determining if U_βEqual to 0, and U_αIf the reference voltage is greater than 0, determining the sector 1 or the sector 6 as the sector where the reference voltage is located; if U is_βEqual to 0, and U_αLess than 0, sector 3 or sector 4 is determined as the sector in which the reference voltage is located.

a fourth determining module 335 for determining if U_αEqual to 0, and U_βIf the voltage is greater than 0, determining the sector 2 as the sector where the reference voltage is located; if U is_αEqual to 0, and U_βLess than 0, sector 5 is determined to be the sector in which the reference voltage is located.

In some embodiments, the expression of the intermediate variable is:

and

in some embodiments, as shown in fig. 5, the apparatus further comprises:

a setting unit 35 for setting the intermediate variable based on the presetDetermining a linear modulation duty ratio expression and an overmodulation duty ratio expression according to the relation X which is Y + Z; the above-mentioned

Embodiments of the third aspect provide a device for determining a duty ratio in SVPWM control, which may be used to execute the method for determining a duty ratio in SVPWM control provided in the embodiments of the first aspect, and the related meanings and specific implementations may refer to the related descriptions in the embodiments of the first aspect, and are not described in detail here.

In a fourth aspect, an embodiment of the present disclosure provides a storage medium including a stored program, where, when the program runs, a device in which the storage medium is controlled to execute the method for determining a duty ratio in SVPWM control according to the first aspect.

The storage medium may include volatile memory in a computer readable medium, Random Access Memory (RAM) and/or nonvolatile memory such as Read Only Memory (ROM) or flash memory (flash RAM), and the memory includes at least one memory chip.

In a fifth aspect, embodiments of the present disclosure provide a human-computer interaction device, which includes a storage medium; and one or more processors, the storage medium coupled with the processors, the processors configured to execute program instructions stored in the storage medium; the program instructions are executed to execute the duty ratio determination method in the SVPWM control according to the first aspect.

In the foregoing embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments.

As will be appreciated by one skilled in the art, embodiments of the present disclosure may be provided as a method, system, or computer program product. Accordingly, embodiments of the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, embodiments of the present disclosure may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and so forth) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the disclosure. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

In a typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

The memory may include forms of volatile memory in a computer readable medium, Random Access Memory (RAM) and/or non-volatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). The memory is an example of a computer-readable medium.

Computer-readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), Digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined herein, a computer readable medium does not include a transitory computer readable medium such as a modulated data signal and a carrier wave.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in the process, method, article, or apparatus that comprises the element.

The above are merely examples of the present application and are not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A duty ratio determination method in SVPWM control is characterized by comprising the following steps:

according to U_α、U_βY and Z, determining the sector where the reference voltage is located;

2. The method of claim 1, wherein the function is according to U_α、U_βY and Z, determining a sector in which the reference voltage is located, comprising:

judge U_βWhether greater than 0;

if yes, according to U_αY and Z determine the sector in which the reference voltage is located among sector 1, sector 2 and sector 3;

otherwise, according to U_αY and Z determine the sector in which the reference voltage is located among sector 4, sector 5 and sector 6.

3. The method of claim 2, whichCharacterized in that said is according to U_αY and Z determine the sector in which the reference voltage is located among sector 1, sector 2 and sector 3, including:

if U is_αIf Z is greater than 0 and less than 0, determining the sector 1 as the sector where the reference voltage is located;

if U is_αIf Y is less than 0 and Y is less than 0, determining sector 3 as the sector where the reference voltage is located;

if U is_αIf Z is greater than 0 and Z is greater than 0, determining the sector 2 as the sector where the reference voltage is located;

if U is_αLess than 0 and Y greater than 0, sector 2 is determined to be the sector in which the reference voltage is located.

4. The method of claim 2, wherein the function is U_αY and Z determine the sector in which the reference voltage is located among sector 4, sector 5 and sector 6, including:

if U is_αIf Z is less than 0 and Z is greater than 0, determining sector 4 as the sector where the reference voltage is located;

if U is_αIf Y is greater than 0 and Y is greater than 0, determining the sector 6 as the sector where the reference voltage is located;

if U is_αIf Z is less than 0 and Z is less than 0, determining the sector 5 as the sector where the reference voltage is located;

if U is_αGreater than 0 and Y less than 0, sector 5 is determined to be the sector in which the reference voltage is located.

5. The method of claim 1, wherein the function is according to U_α、U_βY and Z, determining a sector in which the reference voltage is located, comprising:

if U is_βEqual to 0, and U_αIf the reference voltage is greater than 0, determining the sector 1 or the sector 6 as the sector where the reference voltage is located;

if U is_βEqual to 0, and U_αLess than 0, sector 3 or sector 4 is determined as the sector in which the reference voltage is located.

6. The method of claim 1, wherein the function is according to U_α、U_βY and Z, determining a sector in which the reference voltage is located, comprising:

if U is_αEqual to 0, and U_βIf the voltage is greater than 0, determining the sector 2 as the sector where the reference voltage is located;

if U is_αEqual to 0, and U_βLess than 0, sector 5 is determined to be the sector in which the reference voltage is located.

7. The method according to any of claims 1-6, wherein the expression of the intermediate variable is:

and

8. the method of claim 7, wherein the preset duty cycle expressions comprise a linear modulation duty cycle expression and an overmodulation duty cycle expression, the method further comprising:

determining a linear modulation duty ratio expression and an overmodulation duty ratio expression based on a relation X between preset intermediate variables which is Y + Z; the above-mentioned

9. An apparatus for determining duty ratio in SVPWM control, the apparatus comprising:

a first determination unit for determining a component U of the reference voltage on a horizontal axis among the orthogonal axes_αAnd determining the component U of the reference voltage on the vertical axis among the orthogonal axes_β；

A second determination unit for determining the basis of U_α、U_βAnd DC bus voltage U_dcDetermining an intermediate variable Y, Z;

a third determination unit for determining the value according to U_α、U_βY and Z, determining the sector where the reference voltage is located;

a fourth determining unit, configured to select, according to the sector, Y, and Z, a duty ratio expression corresponding to the sector from preset duty ratio expressions, and determine a duty ratio based on the selected duty ratio expression; the preset duty ratio expression is set based on expressions of intermediate variables Y and Z.

10. The apparatus of claim 9, wherein the third determining unit comprises:

a judging module for judging U_βWhether greater than 0; if yes, a first determining module; otherwise, triggering a second determining module;

the first determining module is used for determining the first time according to the U under the triggering of the judging module_αY and Z determine the sector in which the reference voltage is located among sector 1, sector 2 and sector 3;

the second determining module is used for determining the current position according to U under the triggering of the judging module_αY and Z determine the sector in which the reference voltage is located among sector 4, sector 5 and sector 6.

11. The apparatus of claim 10, wherein the first determining module is configured to determine if U_αIf Z is greater than 0 and less than 0, determining the sector 1 as the sector where the reference voltage is located; if U is_αIf Y is less than 0 and Y is less than 0, determining sector 3 as the sector where the reference voltage is located; if U is_αIf Z is greater than 0 and Z is greater than 0, determining the sector 2 as the sector where the reference voltage is located; if U is_αLess than 0 and Y greater than 0, sector 2 is determined to be the sector in which the reference voltage is located.

12. The apparatus of claim 10, wherein the second determining module is configured to determine if U_αIf Z is less than 0 and Z is greater than 0, determining sector 4 as the sector where the reference voltage is located; if U is_αIf Y is greater than 0 and Y is greater than 0, determining the sector 6 as the sector where the reference voltage is located; if U is_αIf Z is less than 0 and Z is less than 0, determining the sector 5 as the sector where the reference voltage is located; if U is_αGreater than 0 and Y less than 0, sector 5 is determined to be the sector in which the reference voltage is located.

13. The apparatus of claim 9, wherein the third determining unit comprises:

a third determination module for determining if U_βEqual to 0, and U_αIf the reference voltage is greater than 0, determining the sector 1 or the sector 6 as the sector where the reference voltage is located; if U is_βEqual to 0, and U_αLess than 0, sector 3 or sector 4 is determined as the sector in which the reference voltage is located.

14. The apparatus of claim 9, wherein the third determining unit comprises:

a fourth determination module for determining if U_αEqual to 0, and U_βIf the voltage is greater than 0, determining the sector 2 as the sector where the reference voltage is located; if U is_αEqual to 0, and U_βLess than 0, sector 5 is determined to be the sector in which the reference voltage is located.

15. The apparatus according to any of claims 9-14, wherein the expression of the intermediate variable is:

and

16. the apparatus of claim 15, further comprising:

a setting unit for setting based on presetDetermining a linear modulation duty ratio expression and an overmodulation duty ratio expression according to the relation X between the intermediate variables which is Y + Z; the above-mentioned

17. A storage medium comprising a stored program, wherein a device in which the storage medium is located is controlled to execute the duty ratio determination method in SVPWM control according to any one of claims 1 to 8 when the program is executed.

18. A human-computer interaction device, characterized in that the device comprises a storage medium; and one or more processors, the storage medium coupled with the processors, the processors configured to execute program instructions stored in the storage medium; the program instructions when executed perform the duty cycle determination method in SVPWM control according to any one of claims 1 to 8.