Drive motor torque response process modeling method and device

Abstract

The present invention discloses a method and device for modeling a torque response process of a driving motor. The method comprises obtaining torque response data of a driving motor under a torque switching experiment; establishing a transient process time relationship between a rotation speed and a torque based on the torque response data; constructing a correction function of the torque response process of the driving motor based on the transient process time relationship; optimizing the parameters of the correction function using a genetic algorithm, so as to obtain a driving motor torque response process model based on the correction function according to the parameter optimization result. The present invention obtains a mathematical model of the torque response process of the driving motor that can accurately match the experimental data.

Description

Technical Field

[0001] The present invention relates to the technical field of drive systems for pure electric vehicles, and in particular to a method and device for modeling a torque response process of a drive motor. Background Art

[0002] The electrification of vehicles is an important measure to achieve low carbon. The motor is a key component in the vehicle's electric drive system. The motor torque response process directly affects the motor control, which in turn affects the vehicle control effect. At present, there is a problem that the drive motor torque response process model is complex and difficult to describe, resulting in insufficient model accuracy in the existing technology. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0004] To this end, in order to solve the problem that the torque response process model of the driving motor is complex and difficult to describe, the present invention proposes a method for modeling the torque response process of the driving motor. Based on experiments and optimization methods, a high-precision mathematical model of the torque response process of the driving motor is obtained, which can accurately match the experimental data.

[0005] Another object of the present invention is to provide a device for modeling the torque response process of a drive motor.

[0006] To achieve the above object, the present invention provides a method for modeling a torque response process of a driving motor, comprising:

[0007] Obtain the torque response data of the drive motor under the torque switching experiment;

[0008] Establishing a transient process time relationship between speed and torque based on the torque response data;

[0009] Constructing a correction function of the torque response process of the driving motor based on the time relationship of the transient process;

[0010] The parameters of the correction function are optimized by using a genetic algorithm, so as to obtain a driving motor torque response process model based on the correction function according to the parameter optimization result.

[0011] The method for modeling the torque response process of a driving motor according to an embodiment of the present invention may also have the following additional technical features:

[0012] In one embodiment of the present invention, obtaining torque response data of a drive motor in a torque switching experiment includes:

[0013] Allowing the drive motor to run to an initial speed, switching the initial speed to an initial torque, and switching the initial torque to a target torque;

[0014] It is determined whether the target torque reaches the target value, so as to obtain torque response data under different initial rotation speeds, initial torques and target torques according to the determination result.

[0015] In one embodiment of the present invention, the expression of the correction function is:

[0016]

[0017] Among them, T m is the driving motor torque, T0 is the initial torque of the torque switching process, ΔT m is the difference between the target torque and the initial torque during the torque switching process, t s is the time taken for the transient process of the switching process, x i (i=1...5) are torque transient process model parameters.

[0018] In one embodiment of the present invention, the optimization parameters and optimization target expressions in the parameter optimization result are respectively:

[0019] {x1,x2,x3,x4,x5,}

[0020]

[0021] Among them, J is the objective function, L is the number of working conditions, N j is the number of sampling points of the jth working condition, i is the serial number of the working condition sampling point, j is the serial number of the working condition, is the driving motor model torque at the i-th sampling point of the j-th working condition, The actual torque of the drive motor at the i-th sampling point in the j-th operating condition.

[0022] In one embodiment of the present invention, the expression of the driving motor torque response process model is:

[0023]

[0024] To achieve the above object, the present invention provides a device for modeling a torque response process of a driving motor, comprising:

[0025] A response data acquisition module is used to acquire torque response data of the drive motor under a torque switching experiment;

[0026] A time relationship building module, used to establish a transient process time relationship between speed and torque based on the torque response data;

[0027] A correction function determination module, used for constructing a correction function of a drive motor torque response process based on the transient process time relationship;

[0028] The response model building module is used to optimize the parameters of the correction function by using a genetic algorithm, so as to obtain a drive motor torque response process model based on the correction function according to the parameter optimization result.

[0029] The drive motor torque response process modeling method and device of the embodiment of the present invention first conducts a torque switching experiment to obtain torque response data under different initial torques, initial speeds, and target torques. Then, a modified Sigmoid function is proposed, and the transient process time is determined using experimental data. Finally, a genetic algorithm is used to optimize the parameters in the function to obtain the optimal mathematical model of the response process.

[0030] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0032] Figure 1 is a flow chart of a method for modeling a torque response process of a driving motor according to an embodiment of the present invention;

[0033] Figure 2 is a logic schematic diagram of a method for modeling a torque response process of a driving motor according to an embodiment of the present invention;

[0034] Figure 3 is a schematic diagram of a case of a driving motor torque response process according to an embodiment of the present invention;

[0035] Figure 4 A schematic diagram of a case analysis of a driving motor torque response process according to an embodiment of the present invention;

[0036] Figure 5 A schematic diagram of the structure of a device for modeling a torque response process of a drive motor according to an embodiment of the present invention. DETAILED DESCRIPTION

[0037] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0038] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0039] The following describes a method and device for modeling a drive motor torque response process according to an embodiment of the present invention with reference to the accompanying drawings.

[0040] Figure 1 It is a flow chart of a method for modeling a driving motor torque response process according to an embodiment of the present invention.

[0041] like Figure 1 As shown, the method includes but is not limited to the following steps:

[0042] S1, obtaining torque response data of the driving motor under the torque switching experiment;

[0043] S2, establishing a transient process time relationship between speed and torque based on torque response data;

[0044] S3, constructing a correction function of the torque response process of the driving motor based on the time relationship of the transient process;

[0045] S4, optimizing the parameters of the correction function by using a genetic algorithm, so as to obtain a driving motor torque response process model based on the correction function according to the parameter optimization result.

[0046] It is understandable that in order to establish a mathematical model that can accurately describe the torque response process of the drive motor, it is necessary to first obtain experimental data of the response process. To this end, the present invention designs a torque switching experimental scheme, that is, starting from a certain motor speed and torque, switching to another torque experiment, obtaining the motor torque response process curve, and then accurately describing it with a mathematical model.

[0047] Specifically, the present invention conducts a torque switching experiment to obtain torque response data under different initial torques, initial speeds, and target torques. Then, a modified Sigmoid function is proposed, the transient process time is determined using experimental data, and the parameters in the function are optimized using a genetic algorithm to obtain the optimal mathematical model of the response process. Figure 2As shown, first obtain the torque switching test curve, use a small torque to make the drive motor reach the initial speed, then switch to the initial torque, wait for a certain period of time, switch to the target torque, judge whether the target torque reaches the target value, and judge whether it is stable. After the motor torque stabilizes to the target torque, the target torque is switched to zero, and the experiment ends. To obtain the corresponding experimental data. Exemplarily, the initial speed is intervals of a certain speed difference, from 0r / min to the maximum speed. Both the initial torque and the target torque are intervals of a certain torque difference, from the maximum negative torque to the maximum positive torque. For example Figure 3 shown.

[0048] Furthermore, the model parameters are optimized, the influence of the initial speed, initial torque and target torque on the transient process time is analyzed, and the relationship between the transient process time of the drive motor torque that comprehensively considers the speed and torque is established.

[0049] In one embodiment of the present invention, Figure 3 The example of the driving motor torque response process shown in the figure shows that the torque change in the transient process is an S-shaped curve. The present invention assumes that the corresponding expression is:

[0050]

[0051] Among them, T m is the driving motor torque, T0 is the initial torque of the torque switching process, ΔT m is the difference between the target torque and the initial torque during the torque switching process, t s is the time taken for the transient process of the switching process, x i (i=1...5) are torque transient process model parameters.

[0052] The parameters are then optimized using a genetic algorithm:

[0053] Optimization parameters: {x1,x2,x3,x4,x5,};

[0054] Optimization goal:

[0055] Among them, J is the objective function, L is the number of working conditions, N j is the number of sampling points of the jth working condition, i is the serial number of the working condition sampling point, j is the serial number of the working condition, is the driving motor model torque at the i-th sampling point of the j-th working condition, The actual torque of the drive motor at the i-th sampling point in the j-th operating condition.

[0056] Finally, the drive motor torque response process model based on the modified Sigmoid function can be obtained:

[0057]

[0058] Further, the case analysis Figure 4 As shown, it can be seen that the model of the present invention has high accuracy.

[0059] The driving motor torque response process modeling method of the embodiment of the present invention designs a torque switching experimental method to obtain motor torque response experimental data, and obtains a driving motor torque response process mathematical model that can accurately match the experimental data based on the experiment and genetic algorithm optimization method. This method can cover all motor response ranges. At the same time, the modified Sigmoid function proposed in the present invention can better fit the motor torque response curve. In addition, the present invention adopts hierarchical optimization, first optimizing the transient process time, and then optimizing the parameters. The priorities are clear and the model accuracy is high.

[0060] In order to implement the above embodiment, Figure 5 As shown, the present embodiment also provides a driving motor torque response process modeling device 10, the device 10 includes a response data acquisition module 100, a time relationship construction module 200, a correction function determination module 300 and a response model construction module 400;

[0061] The response data acquisition module 100 is used to acquire the torque response data of the drive motor under the torque switching experiment;

[0062] A time relationship building module 200, for establishing a transient process time relationship between speed and torque based on torque response data;

[0063] A correction function determination module 300 is used to construct a correction function of the drive motor torque response process based on the transient process time relationship;

[0064] The response model building module 400 is used to optimize the parameters of the correction function by using a genetic algorithm, so as to obtain a driving motor torque response process model based on the correction function according to the parameter optimization result.

[0065] Furthermore, the response data acquisition module 100 is also used for:

[0066] The drive motor is operated to an initial speed, the initial speed is switched to an initial torque, and the initial torque is switched to a target torque;

[0067] It is determined whether the target torque reaches the target value, so as to obtain torque response data under different initial speeds, initial torques and target torques according to the determination result.

[0068] Furthermore, the expression of the correction function is:

[0069]

[0070] Among them, T m is the driving motor torque, T0 is the initial torque of the torque switching process, ΔTm is the difference between the target torque and the initial torque during the torque switching process, t s is the time taken for the transient process of the switching process, x i (i=1...5) are torque transient process model parameters.

[0071] Furthermore, the expressions of optimization parameters and optimization targets in the parameter optimization results are:

[0072] {x1,x2,x3,x4,x5,}

[0073]

[0074] Among them, J is the objective function, L is the number of working conditions, N j is the number of sampling points of the jth working condition, i is the serial number of the working condition sampling point, j is the serial number of the working condition, is the driving motor model torque at the i-th sampling point of the j-th working condition, The actual torque of the drive motor at the i-th sampling point in the j-th operating condition.

[0075] Furthermore, the expression of the driving motor torque response process model is:

[0076]

[0077] Among them, T m is the driving motor torque, T0 is the initial torque of the torque switching process, ΔT m is the difference between the target torque and the initial torque during the torque switching process, t s It is the time taken for the transient process of the switching process.

[0078] The driving motor torque response process modeling device of the embodiment of the present invention designs a torque switching experiment to obtain motor torque response experimental data, and obtains a driving motor torque response process mathematical model that can accurately match the experimental data based on the experiment and the genetic algorithm optimization method. This embodiment can cover all motor response ranges. At the same time, the modified Sigmoid function proposed in the present invention can better fit the motor torque response curve. In addition, the present invention adopts hierarchical optimization, first optimizing the transient process time, and then optimizing the parameters. The priorities are clear and the model accuracy is high.

[0079] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0080] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

Claims

1. A method for modeling a drive motor torque response process, characterized in that: The method comprises: Obtain the torque response data of the drive motor under the torque switching experiment; Establishing a transient process time relationship between speed and torque based on the torque response data; Constructing a correction function of the torque response process of the driving motor based on the time relationship of the transient process; Optimizing the parameters of the correction function by using a genetic algorithm, so as to obtain a driving motor torque response process model based on the correction function according to the parameter optimization result; The optimization parameters and optimization target expressions in the parameter optimization results are: {x1,x2,x3,x4,x5} Among them, J is the objective function, L is the number of working conditions, N j is the number of sampling points of the jth working condition, i is the serial number of the working condition sampling point, j is the serial number of the working condition, is the driving motor model torque at the i-th sampling point of the j-th working condition, The actual torque of the driving motor at the i-th sampling point in the j-th working condition; The expression of the driving motor torque response process model is: Among them, T m is the driving motor torque, T0 is the initial torque of the torque switching process, ΔT m is the difference between the target torque and the initial torque during the torque switching process, t s is the time taken for the transient process of the switching process, x i (i=1...5) are torque transient process model parameters.

2. The method according to claim 1, characterized in that Obtain the torque response data of the drive motor under the torque switching experiment, including: Allowing the drive motor to run to an initial speed, switching the initial speed to an initial torque, and switching the initial torque to a target torque; It is determined whether the target torque reaches the target value, so as to obtain torque response data under different initial rotation speeds, initial torques and target torques according to the determination result.

3. The method according to claim 2, characterized in that The expression of the correction function is:

4. A device for modeling a driving motor torque response process, characterized in that: include: A response data acquisition module is used to acquire torque response data of the drive motor under a torque switching experiment; A time relationship building module, used to establish a transient process time relationship between speed and torque based on the torque response data; A correction function determination module, used for constructing a correction function of a drive motor torque response process based on the transient process time relationship; A response model building module, used for optimizing the parameters of the correction function by using a genetic algorithm, so as to obtain a drive motor torque response process model based on the correction function according to the parameter optimization result; The expressions of the optimization parameters and optimization objectives in the parameter optimization results are: {x1,x2,x3,x4,x5,} Among them, J is the objective function, L is the number of working conditions, N j is the number of sampling points of the jth working condition, i is the serial number of the working condition sampling point, j is the serial number of the working condition, is the driving motor model torque at the i-th sampling point of the j-th working condition, The actual torque of the driving motor at the i-th sampling point in the j-th working condition; The expression of the driving motor torque response process model is: Among them, T m is the driving motor torque, T0 is the initial torque of the torque switching process, ΔT m is the difference between the target torque and the initial torque during the torque switching process, t s is the time taken for the transient process of the switching process, x i (i=1...5) are torque transient process model parameters.

5. The device according to claim 4, characterized in that The response data acquisition module is further used for: Allowing the drive motor to run to an initial speed, switching the initial speed to an initial torque, and switching the initial torque to a target torque; It is determined whether the target torque reaches the target value, so as to obtain torque response data under different initial rotation speeds, initial torques and target torques according to the determination result.

6. The device according to claim 5, characterized in that The expression of the correction function is:

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