阅读说明：本技术 一种多台直线感应电机的整体控制方法、装置及设备 (Integral control method, device and equipment for multiple linear induction motors ) 是由 梁潇 张志华 吕治国 史黎明 向湘林 党宁 石硕 于 2019-11-26 设计创作，主要内容包括：本发明公开了一种多台直线感应电机的整体控制方法、装置、设备及计算机可读存储介质,以直线感应电机的初级范围内次级长度占比的函数为动态耦合因子,首先按预设规则确定各直线感应电机的动态耦合因子,再以各动态耦合因子建立各直线感应电机的单台直线感应电机数学模型,然后根据各直线感应电机之间的连接关系和各单台直线感应电机数学模型建立各直线感应电机的整体数学模型,考虑到了直线感应电机初、次级的电磁耦合程度时刻发生变化对直线感应电机参数的影响,因此得到了相比于现有技术更加准确的整体数学模型,依据该整体数学模型进行多台直线感应电机的整体控制,可以对不同类型的多台直线感应电机在不同连接方式下的工况进行精准控制。(The invention discloses an integral control method, a device, equipment and a computer readable storage medium of a plurality of linear induction motors, which take a function of the proportion of the secondary length in the primary range of the linear induction motors as a dynamic coupling factor, firstly determine the dynamic coupling factor of each linear induction motor according to a preset rule, then establish a single linear induction motor mathematical model of each linear induction motor by each dynamic coupling factor, then establish the integral mathematical model of each linear induction motor according to the connection relation between each linear induction motor and each single linear induction motor mathematical model, consider the influence of the change of the electromagnetic coupling degree of the primary and secondary of the linear induction motor on the parameters of the linear induction motor, thereby obtaining a more accurate integral mathematical model compared with the prior art, and carrying out the integral control of the plurality of linear induction motors according to the integral model, the working conditions of a plurality of linear induction motors of different types under different connection modes can be accurately controlled.)

1. An integral control method for a plurality of linear induction motors is characterized by comprising the following steps:

determining the dynamic coupling factor of each linear induction motor according to a preset rule; wherein the dynamic coupling factor is a function of a ratio of secondary lengths within a primary range of the linear induction motor;

establishing a single linear induction motor mathematical model of each linear induction motor according to the dynamic coupling factor of each linear induction motor;

establishing an integral mathematical model of each linear induction motor according to the connection relation between each linear induction motor and each single linear induction motor mathematical model;

and performing overall control on each linear induction motor according to the overall mathematical model.

2. The overall control method according to claim 1, wherein the dynamic coupling factor of each linear induction motor is determined according to a preset rule, specifically by the following formula:

a_i＝f_i(x) i＝1,2...n

wherein, a_iThe dynamic coupling factor is the dynamic coupling factor of the ith linear induction motor, x is the secondary displacement of the ith linear induction motor, n is the number of the linear induction motors, and delta is a preset value.

3. The overall control method according to claim 1, wherein the mathematical model of the single linear induction motor specifically comprises a phase voltage model of the single linear induction motor, a phase current model of the single linear induction motor, an output thrust model of the single linear induction motor, and a power factor model of the single linear induction motor;

correspondingly, the integral mathematical model specifically comprises an integral phase voltage model, an integral phase current model, an integral output thrust model and an integral power factor model.

4. The overall control method according to claim 3, characterized in that the single linear induction motor phase voltage model is specifically represented by the following formula:

U_i＝I_i{[R_1i+a_ir′_ei]+j[X_1i+a_ix'_ei+(1-a_i)X_mi]}

correspondingly, when the linear induction motors are connected in series, the integral phase voltage model is specifically represented by the following formula:

when the linear induction motors are connected in parallel, the integral phase voltage model is specifically represented by the following formula:

U_Z＝U_ii＝1,2...n

wherein, U_iIs the effective value of phase voltage of the ith linear induction motor I_iIs the effective value of the phase current, R, of the ith linear induction motor_1iIs a primary one-phase winding resistance of the i-th linear induction motor, a_iIs a dynamic coupling factor r 'of the ith linear induction motor'_eiIs the equivalent active resistance, X, of the i-th linear induction motor_1iIs primary leakage reactance, x 'of the ith linear induction motor'_eiIs the equivalent reactive reactance, X, of the i-th linear induction motor_miThe motor excitation reactance of the ith linear induction motor is n, the number of the linear induction motors is U_ZIs the integral phase voltage.

5. The overall control method according to claim 3, characterized in that the single linear induction motor phase current model is specifically represented by the following formula:

correspondingly, when the linear induction motors are connected in series, the overall phase current model is specifically represented by the following formula:

I_Z＝I_ii＝1,2...n

when the linear induction motors are connected in parallel, the overall phase current model is specifically represented by the following formula:

wherein, U_iPhase voltage of ith linear induction motorEffective value, I_iIs the effective value of the phase current, R, of the ith linear induction motor_1iIs a primary one-phase winding resistance of the i-th linear induction motor, a_iIs a dynamic coupling factor r 'of the ith linear induction motor'_eiIs the equivalent active resistance, X, of the i-th linear induction motor_1iIs primary leakage reactance, x 'of the ith linear induction motor'_eiIs the equivalent reactive reactance, X, of the i-th linear induction motor_miIs the motor excitation reactance of the ith linear induction motor, n is the number of the linear induction motors, I_ZIs the overall phase current.

6. The overall control method according to claim 3, wherein the single linear induction motor output thrust model is specifically represented by the following formula:

accordingly, the overall output thrust model is specifically represented by the following formula:

wherein, F_iIs the output thrust of the ith linear induction motor I_iIs the effective value of the phase current of the ith linear induction motor, a_iIs a dynamic coupling factor r 'of the ith linear induction motor'_eiIs the equivalent active resistance, m, of the i-th linear induction motor₁Is the number of phases, f_iInput frequency, tau, of the i-th linear induction motor_iPolar distance, F, of the i-th linear induction motor_ZAnd n is the number of the linear induction motors.

7. The overall control method of claim 3, wherein the single linear inductor power factor model is specifically represented by the following formula:

accordingly, the overall power factor model is specifically represented by the following formula:

wherein the content of the first and second substances,

8. The utility model provides a many linear induction motor's overall control device which characterized in that includes:

the determining unit is used for determining the dynamic coupling factors of the linear induction motors according to a preset rule; wherein the dynamic coupling factor is a function of a ratio of secondary lengths within a primary range of the linear induction motor;

the initial modeling unit is used for establishing a single linear induction motor mathematical model of each linear induction motor according to the dynamic coupling factor of each linear induction motor;

the integral modeling unit is used for establishing an integral mathematical model of each linear induction motor according to the connection relation between each linear induction motor and each single linear induction motor mathematical model;

and the control unit is used for performing overall control on each linear induction motor according to the overall mathematical model.

9. An overall control apparatus for a plurality of linear induction motors, comprising:

a memory for storing instructions including the steps of the overall control method of the plurality of linear induction motors of any one of claims 1 to 7;

a processor to execute the instructions.

10. A computer-readable storage medium, on which a computer program is stored, wherein the computer program, when being executed by a processor, implements the steps of the overall control method of a plurality of linear induction motors according to any one of claims 1 to 7.

Technical Field

The invention relates to the technical field of mechanical control, in particular to a method, a device and equipment for integrally controlling a plurality of linear induction motors and a computer readable storage medium.

Background

The linear induction motor is applied to multiple purposes in industry under the condition that a single frequency converter is provided with a plurality of linear induction motors, and usually the plurality of linear induction motors share one secondary reaction plate, such as low-speed magnetic suspension trains in advanced rail transit, electromagnetic ejection in national defense application and the like. In these applications, total thrust and energy efficiency are the control targets. In order to obtain a high-performance control effect, the frequency converter needs an accurate integral mathematical model and electromagnetic parameters of the multiple motors, so that integral modeling and electromagnetic parameter extraction of the multiple linear induction motors are very important.

For the modeling method of the conventional linear induction motor, reference may be made to two patents with publication numbers CN105868485A and CN105787158A, which respectively disclose modeling methods of a switched reluctance linear motor and a permanent magnet synchronous linear motor, but since the operation mechanism of the linear induction motor is very different from that of the former two linear motors, the modeling methods provided by the above patents are not suitable. The other existing modeling method for multiple linear induction motors is to build a mathematical model of a single linear induction motor by referring to a modeling method for multiple rotating motors and then perform equivalent modeling according to the series-parallel relation between the motors. For the working condition that a plurality of short secondary linear induction motors operate simultaneously, an equivalent mathematical model with unchanged parameters under serial/parallel connection of short secondary linear induction motor windings is established in an article of theory and electromagnetic design method of the linear induction motor.

It can be seen that, in the prior art, when modeling control is performed on the whole of a plurality of linear induction motors, modeling is performed on the premise that parameters of the linear induction motors are not changed under series/parallel connection. However, in the case where a plurality of short secondary linear induction motors are connected in parallel, the electromagnetic coupling degree of the primary and secondary of a single motor changes all the time, which affects the overall impedance of the motor. Therefore, the method for integrally modeling and controlling the plurality of linear induction motors in the prior art cannot accurately establish an integral mathematical model and electromagnetic parameters under the condition that the plurality of short secondary linear induction motors are connected in parallel, and is not beneficial to control under the working condition.

The technical problem to be solved by technical personnel in the field is to provide an integral control method suitable for a plurality of linear induction motors of different types in different connection modes.

Disclosure of Invention

The invention aims to provide a method, a device and equipment for integrally controlling a plurality of linear induction motors and a computer readable storage medium, which can adapt to working conditions of a plurality of linear induction motors of different types under different connection modes.

In order to solve the above technical problem, the present invention provides a method for integrally controlling a plurality of linear induction motors, comprising:

determining the dynamic coupling factor of each linear induction motor according to a preset rule; wherein the dynamic coupling factor is a function of a ratio of secondary lengths within a primary range of the linear induction motor;

establishing a single linear induction motor mathematical model of each linear induction motor according to the dynamic coupling factor of each linear induction motor;

establishing an integral mathematical model of each linear induction motor according to the connection relation between each linear induction motor and each single linear induction motor mathematical model;

and performing overall control on each linear induction motor according to the overall mathematical model.

Optionally, the dynamic coupling factor of each linear induction motor is determined according to a preset rule, and is specifically determined by the following formula:

a_i＝f_i(x) i＝1,2...n

wherein, a_iThe dynamic coupling factor is the dynamic coupling factor of the ith linear induction motor, x is the secondary displacement of the ith linear induction motor, n is the number of the linear induction motors, and delta is a preset value.

Optionally, the mathematical model of the single linear induction motor specifically includes a phase voltage model of the single linear induction motor, a phase current model of the single linear induction motor, an output thrust model of the single linear induction motor, and a power factor model of the single linear induction motor;

correspondingly, the integral mathematical model specifically comprises an integral phase voltage model, an integral phase current model, an integral output thrust model and an integral power factor model.

Optionally, the phase voltage model of the single linear induction motor is specifically represented by the following formula:

U_i＝I_i{[R_1i+a_ir′_ei]+j[X_1i+a_ix′_ei+(1-a_i)X_mi]}

correspondingly, when the linear induction motors are connected in series, the integral phase voltage model is specifically represented by the following formula:

when the linear induction motors are connected in parallel, the integral phase voltage model is specifically represented by the following formula:

U_Z＝U_ii＝1,2...n

wherein, U_iIs the effective value of phase voltage of the ith linear induction motor I_iIs the effective value of the phase current, R, of the ith linear induction motor_1iIs a primary one-phase winding resistance of the i-th linear induction motor, a_iIs a dynamic coupling factor r 'of the ith linear induction motor'_eiIs the equivalent active resistance, X, of the i-th linear induction motor_1iIs primary leakage reactance, x 'of the ith linear induction motor'_eiIs the equivalent reactive reactance, X, of the i-th linear induction motor_miThe motor excitation reactance of the ith linear induction motor is n, the number of the linear induction motors is U_ZIs the integral phase voltage.

Optionally, the phase current model of the single linear induction motor is specifically represented by the following formula:

correspondingly, when the linear induction motors are connected in series, the overall phase current model is specifically represented by the following formula:

I_Z＝I_ii＝1,2...n

when the linear induction motors are connected in parallel, the overall phase current model is specifically represented by the following formula:

wherein, U_iIs the effective value of phase voltage of the ith linear induction motor I_iIs the effective value of the phase current, R, of the ith linear induction motor_1iIs a primary one-phase winding resistance of the i-th linear induction motor, a_iIs a dynamic coupling factor r 'of the ith linear induction motor'_eiIs the equivalent active resistance, X, of the i-th linear induction motor_1iIs the primary leakage of the ith linear induction motorAnti, x'_eiIs the equivalent reactive reactance, X, of the i-th linear induction motor_miIs the motor excitation reactance of the ith linear induction motor, n is the number of the linear induction motors, I_ZIs the overall phase current.

Optionally, the output thrust model of the single linear induction motor is specifically represented by the following formula:

accordingly, the overall output thrust model is specifically represented by the following formula:

wherein, F_iIs the output thrust of the ith linear induction motor I_iIs the effective value of the phase current of the ith linear induction motor, a_iIs a dynamic coupling factor r 'of the ith linear induction motor'_eiIs the equivalent active resistance, m, of the i-th linear induction motor₁Is the number of phases, f_iInput frequency, tau, of the i-th linear induction motor_iPolar distance, F, of the i-th linear induction motor_ZAnd n is the number of the linear induction motors.

Optionally, the power factor model of the single linear inductor is specifically represented by the following formula:

accordingly, the overall power factor model is specifically represented by the following formula:

wherein the content of the first and second substances,is the power factor, R, of the ith linear induction motor_1iIs a primary one-phase winding resistance of the i-th linear induction motor, a_iIs a dynamic coupling factor r 'of the ith linear induction motor'_eiIs the equivalent active resistance, X, of the i-th linear induction motor_1iIs primary leakage reactance, x 'of the ith linear induction motor'_eiIs the equivalent reactive reactance, X, of the i-th linear induction motor_miThe excitation reactance of the motor of the ith linear induction motor,is the overall power factor, n is the number of the linear induction motors, I_iThe effective value of the phase current of the ith linear induction motor is obtained.

In order to solve the above technical problem, the present invention further provides an overall control apparatus for a plurality of linear induction motors, comprising:

the determining unit is used for determining the dynamic coupling factors of the linear induction motors according to a preset rule; wherein the dynamic coupling factor is a function of a ratio of secondary lengths within a primary range of the linear induction motor;

the initial modeling unit is used for establishing a single linear induction motor mathematical model of each linear induction motor according to the dynamic coupling factor of each linear induction motor;

the integral modeling unit is used for establishing an integral mathematical model of each linear induction motor according to the connection relation between each linear induction motor and each single linear induction motor mathematical model;

and the control unit is used for performing overall control on each linear induction motor according to the overall mathematical model.

In order to solve the above technical problem, the present invention further provides an overall control apparatus for a plurality of linear induction motors, comprising:

a memory for storing instructions including any one of the steps of the method for integrally controlling a plurality of linear induction motors;

a processor to execute the instructions.

In order to solve the above technical problem, the present invention further provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the method for integrally controlling a plurality of linear induction motors as described in any one of the above.

The invention provides an integral control method of a plurality of linear induction motors, which takes a function of the proportion of the secondary length in the primary range of the linear induction motors as a dynamic coupling factor, firstly determines the dynamic coupling factor of each linear induction motor according to a preset rule, then establishes a single linear induction motor mathematical model of each linear induction motor according to the dynamic coupling factor of each linear induction motor, then establishes an integral mathematical model of each linear induction motor according to the connection relation among the linear induction motors and the mathematical model of each single linear induction motor, considers the influence of the change of the electromagnetic coupling degree of the primary and secondary of the linear induction motors on the parameters of the linear induction motors at any moment, thereby obtaining a more accurate integral mathematical model compared with the prior art, and carrying out the integral control of each linear induction motor according to the integral mathematical model established in the way, the linear induction motor can adapt to the working conditions of a plurality of linear induction motors of different types under different connection modes, and achieves accurate control over various working conditions. The invention also provides an integral control device, equipment and a computer readable storage medium of the multiple linear induction motors, which have the beneficial effects and are not described again.

Drawings

In order to more clearly illustrate the embodiments or technical solutions of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.

Fig. 1 is a flowchart of an overall control method for a plurality of linear induction motors according to an embodiment of the present invention;

fig. 2 is a schematic operation diagram of a single short primary linear induction motor according to an embodiment of the present invention;

fig. 3 is a schematic operation diagram of a single short secondary linear induction motor according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a dynamic-type equivalent circuit of a single short primary linear induction motor during operation according to an embodiment of the present invention;

fig. 5 is a schematic diagram of a dynamic-type equivalent circuit of a single short secondary linear induction motor during operation according to an embodiment of the present invention;

fig. 6 is a schematic diagram of a dynamic-one equivalent circuit when multiple linear induction motors connected in series operate according to an embodiment of the present invention;

fig. 7 is a schematic diagram of a dynamic one-type equivalent circuit during operation of a plurality of linear induction motors connected in parallel according to an embodiment of the present invention;

fig. 8 is a schematic diagram of a dynamic one-type equivalent circuit of three short secondary linear induction motors connected in series according to an embodiment of the present invention during operation;

fig. 9 is a schematic structural diagram of an overall control apparatus for a plurality of linear induction motors according to an embodiment of the present invention;

fig. 10 is a schematic structural diagram of an overall control apparatus for multiple linear induction motors according to an embodiment of the present invention.

Detailed Description

The core of the invention is to provide a method, a device and equipment for integrally controlling a plurality of linear induction motors and a computer readable storage medium, which can adapt to the working conditions of a plurality of linear induction motors of different types under different connection modes.

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 only a part of the embodiments of the present invention, and not all of the 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.

Fig. 1 is a flowchart of an overall control method for a plurality of linear induction motors according to an embodiment of the present invention; fig. 2 is a schematic operation diagram of a single short primary linear induction motor according to an embodiment of the present invention; fig. 3 is a schematic operation diagram of a single short secondary linear induction motor according to an embodiment of the present invention.

As shown in fig. 1, the method for integrally controlling a plurality of linear induction motors according to an embodiment of the present invention includes:

s101: and determining the dynamic coupling factor of each linear induction motor according to a preset rule.

Wherein the dynamic coupling factor is a function of the ratio of the lengths of the secondary stages in the primary range of the linear induction motor.

In the specific implementation, a mathematical model of each linear induction motor is established, namely the mathematical model of a single linear induction motor, and the characteristics of the linear induction motor in various running states are accurately represented through the mathematical model of the single linear induction motor, and the influence of the variation of the primary and secondary coupling degrees on the motor impedance during running is also accurately represented. And integrating the mathematical models of the single linear induction motor into an integral dynamic model of the multiple induction motors according to the connection mode among the linear induction motors. Through the separate calculation and the collective analysis of all the linear induction motors, the accurate overall dynamic characteristic can be obtained only by a small calculation amount.

In the operation process of the linear induction motor, particularly in the operation process of a plurality of short secondary linear induction motors under parallel connection, the secondary of each linear induction motor is displaced compared with the primary, so that the embodiment of the invention takes the function of the proportion of the lengths of the secondary in the primary range of the linear induction motor as the dynamic coupling factor, and before a single linear induction motor mathematical model is established, the dynamic coupling factor of each linear induction motor is firstly determined.

Determining the dynamic coupling factor of each linear induction motor according to a preset rule, wherein the dynamic coupling factor can be determined by the following formula:

a_i＝f_i(x) i＝1,2...n (1)

wherein, a_iThe dynamic coupling factor of the ith linear induction motor is shown, x is the secondary displacement of the ith linear induction motor, n is the number of the linear induction motors, and delta is a preset value.

The formula (2) shows that under the common working condition, the sum of the dynamic coupling factors of all the linear induction motors is a constant value. Generally, a plurality of linear induction motors connected in series or in parallel are all linear induction motors of the same type, so that the formula (1) can be expressed as a_i＝f(x)，i＝1,2...n。

Dynamic coupling factor a when the primary and secondary of a linear induction motor are fully electromagnetically coupled_i1, the mathematical model of the single linear induction motor is a 'one-type' equivalent model.

If the linear induction motor is of a short primary structure, as shown in fig. 2, the primary and secondary of a single short primary linear induction motor are always completely electromagnetically coupled, the dynamic coupling factor of each linear induction motor is kept at 1, and is independent of the secondary displacement, i.e., a_i＝1，i＝1,2...n。

If the linear induction motors are of short secondary structure, as shown in fig. 3, the dynamic coupling factor a of each linear induction motor is now set_iThe variation range is 0-a with the variation of the secondary displacement_i≤1。

S102: and establishing a single linear induction motor mathematical model of each linear induction motor according to the dynamic coupling factor of each linear induction motor.

S103: and establishing an integral mathematical model of each linear induction motor according to the connection relation among the linear induction motors and the mathematical model of each single linear induction motor.

In the specific implementation, the mathematical model of the single linear induction motor specifically comprises a phase voltage model of the single linear induction motor, a phase current model of the single linear induction motor, an output thrust model of the single linear induction motor and a power factor model of the single linear induction motor;

correspondingly, the overall mathematical model specifically comprises an overall phase voltage model, an overall phase current model, an overall output thrust model and an overall power factor model.

S104: and carrying out integral control on each linear induction motor according to the integral mathematical model.

The integral control method of multiple linear induction motors provided by the embodiment of the invention takes the function of the proportion of the secondary length in the primary range of the linear induction motor as the dynamic coupling factor, firstly determines the dynamic coupling factor of each linear induction motor according to the preset rule, then establishes the mathematical model of a single linear induction motor of each linear induction motor according to the dynamic coupling factor of each linear induction motor, then establishes the integral mathematical model of each linear induction motor according to the connection relation between each linear induction motor and each mathematical model of the single linear induction motor, considers the influence of the change of the electromagnetic coupling degree of the primary and secondary of the linear induction motor on the parameters of the linear induction motor at any moment, thereby obtaining the more accurate integral mathematical model compared with the prior art, and carrying out the integral control of each linear induction motor according to the integral mathematical model established in the way, the linear induction motor can adapt to the working conditions of a plurality of linear induction motors of different types under different connection modes, and achieves accurate control over various working conditions.

Fig. 4 is a schematic diagram of a dynamic-type equivalent circuit of a single short primary linear induction motor during operation according to an embodiment of the present invention; fig. 5 is a schematic diagram of a dynamic-type equivalent circuit of a single short secondary linear induction motor during operation according to an embodiment of the present invention; fig. 6 is a schematic diagram of a dynamic-one equivalent circuit when multiple linear induction motors connected in series operate according to an embodiment of the present invention; fig. 7 is a schematic diagram of a dynamic one-type equivalent circuit during operation of a plurality of linear induction motors connected in parallel according to an embodiment of the present invention; fig. 8 is a schematic diagram of a dynamic equivalent circuit of three short secondary linear induction motors connected in series according to an embodiment of the present invention during operation.

On the basis of the above embodiment, in another embodiment, for step S102 and step S103 in fig. 1, the embodiment of the present invention provides a specific modeling method.

As shown in figure 4, the primary and secondary of a single short primary linear induction motor are always completely electromagnetically coupled, and the dynamic one-type equivalent circuit of the motor in operation is a primary one-phase winding resistor R₁Primary leakage reactance X₁And equivalent active resistance r'_eAnd equivalent reactive reactance x'_eThe series circuit of (1).

As shown in FIG. 5, when the primary and secondary of a single short secondary linear induction motor are completely electromagnetically coupled, the dynamic one-type equivalent circuit is the resistance R of the primary-phase winding₁Primary leakage reactance X₁And equivalent active resistance r'_eAnd equivalent reactive reactance x'_eAnd a motor excitation reactance (1-a)₁)X_mIn which equivalent active resistance r 'is provided'_eAnd equivalent reactive reactance x'_eAnd the motor excitation reactance by a dynamic coupling factor a₁The influence of (c).

Then, for step S102 in fig. 1, the phase voltage model of the single linear induction motor can be specifically represented by the following formula:

U_i＝I_i{[R_1i+a_ir′_ei]+j[X_1i+a_ix′_ei+(1-a_i)X_mi]} (3)

wherein, U_iIs the effective value of phase voltage of the ith linear induction motor I_iEffective value of phase current, R, of ith linear induction motor_1iIs a primary one-phase winding resistance of the ith linear induction motor, a_iIs a dynamic coupling factor r 'of the ith linear induction motor'_eiIs the equivalent active resistance, X, of the ith linear induction motor_1iIs primary leakage reactance, x 'of the ith linear induction motor'_eiIs the equivalent reactive reactance, X, of the ith linear induction motor_miThe motor excitation reactance of the ith linear induction motor is 1,2.. n, and n is the number of the linear induction motors.

The phase current model of the single linear induction motor is specifically represented by the following formula:

wherein, U_iIs the effective value of phase voltage of the ith linear induction motor I_iEffective value of phase current, R, of ith linear induction motor_1iIs a primary one-phase winding resistance of the ith linear induction motor, a_iIs a dynamic coupling factor r 'of the ith linear induction motor'_eiIs the equivalent active resistance, X, of the ith linear induction motor_1iIs primary leakage reactance, x 'of the ith linear induction motor'_eiIs the equivalent reactive reactance, X, of the ith linear induction motor_miThe excitation reactance is the motor excitation reactance of the ith linear induction motor.

The output thrust model of the single linear induction motor is specifically represented by the following formula:

wherein, F_iIs the output thrust of the ith linear induction motor I_iIs the effective value of phase current of the ith linear induction motor, a_iIs a dynamic coupling factor r 'of the ith linear induction motor'_eiIs the equivalent active resistance, m, of the ith linear induction motor₁Is the number of phases, f_iInput frequency, τ, of the ith linear induction motor_iAnd the polar distance of the ith linear induction motor.

The power factor model of the single linear induction motor is specifically represented by the following formula:

wherein the content of the first and second substances,is the power factor, R, of the ith linear induction motor_1iIs a primary one-phase winding resistance of the ith linear induction motor, a_iIs as followsDynamic coupling factor r 'of i linear induction motors'_eiIs the equivalent active resistance, X, of the ith linear induction motor_1iIs primary leakage reactance, x 'of the ith linear induction motor'_eiIs the equivalent reactive reactance, X, of the ith linear induction motor_miThe excitation reactance is the motor excitation reactance of the ith linear induction motor.

In the above formula, the equivalent active resistance and the equivalent reactive reactance are equivalent electromagnetic impedances converted from T-type equivalent circuits of the linear induction motor, represent the active resistance and the reactive reactance of each phase of the primary to the secondary of the motor transmitted through the air gap, and take into account the lateral and longitudinal end effects of the linear induction motor.

Accordingly, for step S103 in fig. 1, the integral phase voltage model and the integral phase current model are influenced by the connection manner of the linear induction motor. Fig. 6 shows a dynamic one-type equivalent circuit when linear induction motors of the same type are connected in series and fig. 7 shows a dynamic one-type equivalent circuit when linear induction motors of the same type are connected in parallel.

As shown in fig. 6, when the linear induction motors are connected in series, the overall phase voltage model is specifically represented by the following formula:

considering that a plurality of linear induction motors, which are generally connected together, are of the same type, equation (7) can also be expressed as:

as shown in fig. 8, taking 3 linear induction motors (n is 3) connected in series and each linear induction motor being of the same type as an example, the sum of the dynamic coupling factors of all the linear induction motors is taken as the sum

It is possible to establish an overall mathematical model thereof, in which the primary one-phase winding is wound, according to equation (8)Resistance of 3R₁Equivalent active resistance of 1.2 r'_ePrimary leakage reactance of 3X₁Equivalent reactive reactance of 3 x'_eThe excitation reactance of the motor is 1.8X_mWherein R is₁、r′_e、X₁、x′_e、X_mAre all electromagnetic parameters of a linear induction motor. Due to the series connection mode, the electromagnetic parameters are all constant values.

As shown in fig. 7, when the linear induction motors are connected in parallel, the overall phase voltage model is specifically represented by the following formula:

U_Z＝U_ii＝1,2...n (9)

wherein n is the number of linear induction motors, U_ZIs the integral phase voltage.

When the linear induction motors are connected in series, the overall phase current model is specifically represented by the following formula:

I_Z＝I_ii＝1,2...n (10)

when all the linear induction motors are connected in parallel, the overall phase current model is specifically represented by the following formula:

wherein n is the number of linear induction motors, I_ZIs the overall phase current.

The integral output thrust is the sum of the output thrust of each single linear induction motor, so the integral output thrust model is specifically represented by the following formula:

wherein, F_ZAnd n is the number of the linear induction motors.

The overall power factor is obtained according to the phase current effective value of each single linear induction motor and the power factor of each single linear induction motor, and is specifically represented by the following formula:

wherein the content of the first and second substances,

is the overall power factor, n is the number of linear induction motors, I_iThe effective value of the phase current of the ith linear induction motor is obtained.

On the basis of the above detailed description of the various embodiments corresponding to the overall control method of the multiple linear induction motors, the invention also discloses an overall control device of the multiple linear induction motors corresponding to the method.

Fig. 9 is a schematic structural diagram of an overall control device for a plurality of linear induction motors according to an embodiment of the present invention.

As shown in fig. 9, an overall control apparatus for a plurality of linear induction motors according to an embodiment of the present invention includes:

a determining unit 901, configured to determine a dynamic coupling factor of each linear induction motor according to a preset rule; the dynamic coupling factor is a function of the proportion of the secondary length in the primary range of the linear induction motor;

an initial modeling unit 902, configured to establish a mathematical model of a single linear induction motor of each linear induction motor according to the dynamic coupling factor of each linear induction motor;

the integral modeling unit 903 is used for establishing an integral mathematical model of each linear induction motor according to the connection relation among the linear induction motors and the mathematical model of each single linear induction motor;

and a control unit 904, configured to perform overall control on each linear induction motor according to the overall mathematical model.

Since the embodiments of the apparatus portion and the method portion correspond to each other, please refer to the description of the embodiments of the method portion for the embodiments of the apparatus portion, which is not repeated here.

Fig. 10 is a schematic structural diagram of an overall control apparatus for multiple linear induction motors according to an embodiment of the present invention.

As shown in fig. 10, an overall control apparatus for a plurality of linear induction motors according to an embodiment of the present invention includes:

a memory 1001 for storing instructions including the steps of the method for integrally controlling a plurality of linear induction motors according to any one of the above embodiments;

a processor 1002 for executing the instructions.

The overall control device for a plurality of linear induction motors according to this embodiment can call the computer program stored in the memory by the processor to realize the steps of the overall control method for a plurality of linear induction motors according to any one of the above embodiments, and therefore the analysis apparatus has the same practical effects as the overall control method for a plurality of linear induction motors.

In order to better understand the present solution, an embodiment of the present invention further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the steps of the overall control method for multiple linear induction motors are implemented as in any one of the above-mentioned embodiments.

The computer-readable storage medium provided in this embodiment may call a computer program stored in the computer-readable storage medium through a processor to implement the steps of the method for integrally controlling a plurality of linear induction motors according to any one of the above embodiments, so that the computer-readable storage medium has the same practical effects as the method for integrally controlling a plurality of linear induction motors.

In the several embodiments provided in the present application, it should be understood that the disclosed method, apparatus, device and computer-readable storage medium may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, a division of modules is merely a division of logical functions, and an actual implementation may have another division, for example, a plurality of modules or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or modules, and may be in an electrical, mechanical or other form. Modules described as separate parts may or may not be physically separate, and parts displayed as modules may or may not be physical modules, may be located in one place, or may be distributed on a plurality of network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment.

In addition, functional modules in the embodiments of the present application may be integrated into one processing module, or each of the modules may exist alone physically, or two or more modules are integrated into one module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode.

The integrated module, if implemented in the form of a software functional module and sold or used as a separate product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be substantially implemented or contributed to by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a function calling device, or a network device) to execute all or part of the steps of the method of the embodiments of the present application. And the aforementioned computer-readable storage media may include: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

The present invention provides a method, an apparatus, a device and a computer readable storage medium for integrally controlling a plurality of linear induction motors. The embodiments are described in a progressive manner in the specification, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.

It is further noted that, in the present specification, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, 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 a process, method, article, or apparatus that comprises the element.