Model prediction control method and system for PWM rectifier

Abstract

The invention relates to the technical field of PWM rectifier control, and provides a model prediction control method and system for a PWM rectifier. The method comprises the steps of obtaining initial battery capacity of the electric vehicle; a standard charging voltage control curve of the electric vehicle and a standard battery capacity change curve in the charging process are obtained, and a charging voltage control curve of the electric vehicle is generated based on the standard charging voltage control curve, the standard battery capacity change curve and the initial battery capacity; determining a charging duration of the charging voltage control curve, and determining a charging time period based on a preset delay duration and the charging duration; predicting the input voltage change information of the PWM rectifier in the charging time period to obtain input voltage change prediction information of the PWM rectifier in the charging time period; and generating a PWM signal control model based on the charging voltage control curve and the input voltage change prediction information, and controlling the PWM rectifier in the charging time period based on the PWM signal control model. The method is helpful for improving the charging safety.

Description

Technical Field

[0001] The present application relates to the technical field of PWM rectifier control, and particularly to a model predictive control method and system for a PWM rectifier. Background Art

[0002] With the booming development of the electric vehicle industry, charging infrastructure has become a key component to support the popularization of electric vehicles. As the core device for charging the batteries of electric vehicles, charging piles have gradually become one of the key devices to ensure fast charging of electric vehicles and improve the usage experience. Existing charging piles usually adopt a DC charging method based on PWM rectifiers.

[0003] The PWM rectifier realizes the rectification of the AC power supply and the regulation of the DC voltage by controlling the switching frequency, which is crucial for the safety of charging the batteries of electric vehicles. However, existing PWM rectifier control methods usually generate PWM control signals in real time based on the charging voltage of the electric vehicle and the input voltage of the PWM rectifier during the charging process of the electric vehicle. This control method is prone to the occurrence of battery overcharging problems due to the delay in generating the PWM control signals, thereby causing a series of safety hazards. Summary of the Invention

[0004] The present application provides a model predictive control method and system for a PWM rectifier to solve the problems raised in the above background art.

[0005] In a first aspect, the present application provides a model predictive control method for a PWM rectifier, where the PWM rectifier is used for a charging pile, and the method includes: Responding to a charging request of an electric vehicle and obtaining the initial battery capacity of the battery of the electric vehicle; Obtaining the standard charging voltage control curve and the standard battery capacity change curve during the charging process of the electric vehicle in a database, and generating a charging voltage control curve of the electric vehicle based on the standard charging voltage control curve, the standard battery capacity change curve, and the initial battery capacity; Determining the charging duration corresponding to the charging voltage control curve, and determining the charging time period of the electric vehicle based on a preset delay duration and the charging duration; Predicting the input voltage change information of the PWM rectifier during the charging time period to obtain the input voltage change prediction information of the PWM rectifier during the charging time period; Generating a PWM signal control model corresponding to the PWM rectifier during the charging time period based on the charging voltage control curve and the input voltage change prediction information, and controlling the PWM rectifier during the charging time period based on the PWM signal control model.

[0006] In a possible implementation, predicting the input voltage change information of the PWM rectifier during the charging period to obtain the input voltage change prediction information of the PWM rectifier during the charging period includes: Obtaining the historical input voltage change curve information of the PWM rectifier during the charging period; wherein, the historical input voltage change curve information includes a plurality of historical input voltage change curves; Plotting each of the historical input voltage change curves in the same rectangular coordinate system; the abscissa of the rectangular coordinate system represents time, and the ordinate represents the input voltage; Segmenting the charging period at a time interval of 0.1 ms in the rectangular coordinate system to obtain a plurality of time points; For each of the time points, determining the maximum input voltage among the input voltage values corresponding to each of the historical input voltage change curves at the time point as the input voltage prediction value corresponding to the time point; Generating the input voltage change prediction information based on the input voltage prediction values corresponding to each of the time points.

[0007] In a possible implementation, generating the PWM signal control model corresponding to the PWM rectifier during the charging period based on the charging voltage control curve and the input voltage change prediction information includes: For each of the time points, determining the charging voltage corresponding to the time point on the charging voltage control curve, and determining the PWM duty cycle corresponding to the time point based on the charging voltage corresponding to the time point and the input voltage prediction value; Generating a PWM duty cycle change curve during the charging period based on the PWM duty cycles corresponding to each of the time points; the PWM duty cycle change curve is the PWM signal control model.

[0008] In a possible implementation, after charging the electric vehicle during the charging period based on the PWM signal control model, the method further includes: Obtaining the battery capacity of the electric vehicle and determining whether the battery capacity is greater than a preset battery capacity; If not, repeatedly iterating the steps of generating the charging voltage control curve of the electric vehicle based on the standard charging voltage control curve, the standard battery capacity change curve, and the initial battery capacity and subsequent steps until the battery capacity is greater than the preset battery capacity; If so, sending a charging completion prompt message to the user of the electric vehicle.

[0009] In a possible implementation, obtaining the standard charging voltage control curve of the electric vehicle and the standard battery capacity change curve during the charging process in the database includes: Controlling a preset camera device to obtain the license plate image of the electric vehicle, and obtaining the license plate number of the electric vehicle based on the license plate image; Generating a decryption password based on the license plate number; Simultaneously decrypting each encrypted folder in the database based on the decryption password, and determining the decrypted successful encrypted folder as the target encrypted folder; the target encrypted folder is provided with texts corresponding to multiple life stages of the battery; Obtaining the remaining life of the battery, and determining the target text in the target encrypted folder based on the remaining life; the target text is provided with the standard charging voltage control curve and the standard battery capacity change curve.

[0010] In a possible implementation, generating the decryption password based on the license plate number includes: Judging whether there are Chinese characters in the license plate number; If there are Chinese characters, replacing the Chinese characters in the license plate number with a pinyin sequence and deleting the special characters in the license plate number to obtain a character sequence; If there are no Chinese characters, deleting the special characters in the license plate number to obtain a character sequence; Determining the value corresponding to the number of digits in the character sequence as the first target value, and determining the value corresponding to the number of letters in the character sequence as the second target value; Obtaining a preset coding algorithm matrix in the database; Determining a first target coding algorithm in the coding algorithm matrix based on the first target value and the second target value; the value corresponding to the row number where the first target coding algorithm is located is consistent with the first target value, and the value corresponding to the column number where the first target coding algorithm is located is consistent with the second target value; Encoding each letter in the character sequence based on the first target coding algorithm to obtain an encoding sequence corresponding to each letter; For each digit in the character sequence, obtaining the sum of squares corresponding to the digit, and determining the second target coding algorithm corresponding to the digit in the coding algorithm matrix based on the digit and the sum of squares corresponding to the digit, and encoding the digit based on the second target coding algorithm to obtain an encoding sequence corresponding to the digit; wherein, the value corresponding to the row number where the second target coding algorithm is located is consistent with the digit, and the value corresponding to the column number where the second target coding algorithm is located is consistent with the sum of squares; Arrange each of the encoding sequences in sequence based on the positions of the characters corresponding to the respective encoding sequences in the character sequence to obtain the decryption password.

[0011] In a second aspect, the present application provides a model predictive control system for a PWM rectifier, where the PWM rectifier is used for a charging pile, and the system includes: An acquisition module, configured to respond to a charging request of an electric vehicle and acquire an initial battery capacity of the battery of the electric vehicle. A generation module, configured to obtain a standard charging voltage control curve of the electric vehicle and a standard battery capacity change curve during the charging process in a database, and generate a charging voltage control curve of the electric vehicle based on the standard charging voltage control curve, the standard battery capacity change curve, and the initial battery capacity. A determination module, configured to determine a charging duration corresponding to the charging voltage control curve, and determine a charging time period of the electric vehicle based on a preset delay duration and the charging duration. A prediction module, configured to predict input voltage change information of the PWM rectifier during the charging time period to obtain input voltage change prediction information of the PWM rectifier during the charging time period. A control module, configured to generate a PWM signal control model corresponding to the PWM rectifier during the charging time period based on the charging voltage control curve and the input voltage change prediction information, and control the PWM rectifier during the charging time period based on the PWM signal control model.

[0012] The present application provides a model predictive control method and system for a PWM rectifier, where the PWM rectifier is used for a charging pile, and the method includes: responding to a charging request of an electric vehicle and acquiring an initial battery capacity of the battery of the electric vehicle; obtaining a standard charging voltage control curve of the electric vehicle and a standard battery capacity change curve during the charging process in a database, and generating a charging voltage control curve of the electric vehicle based on the standard charging voltage control curve, the standard battery capacity change curve, and the initial battery capacity. Determine the charging duration corresponding to the charging voltage control curve, and determine the charging time period of the electric vehicle based on a preset delay duration and the charging duration; predict the input voltage change information of the PWM rectifier during the charging time period to obtain the predicted input voltage change information of the PWM rectifier during the charging time period; generate a PWM signal control model corresponding to the PWM rectifier during the charging time period based on the charging voltage control curve and the predicted input voltage change information, and control the PWM rectifier during the charging time period based on the PWM signal control model. By predicting the PWM signal control model during the charging process before charging the electric vehicle, it is possible to effectively avoid the problem of overcharging the battery caused by the delay in generating the PWM control signal, which helps to improve the safety during the charging process. Description of the Drawings

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0014] Figure 1 Flow chart of the model predictive control method for the PWM rectifier provided by the embodiment of the present application; Figure 2 Structural schematic block diagram of the model predictive control system for the PWM rectifier provided by the embodiment of the present application; Figure 3 Structural schematic block diagram of the terminal device provided by the embodiment of the present application. Detailed Embodiments

[0015] 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. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the protection scope of the present invention.

[0016] The flow chart shown in the drawings is only an example, and does not necessarily include all the contents and operations / steps, nor does it necessarily need to be executed in the described order. For example, some operations / steps can be decomposed, combined, or partially merged, so the actual execution order may change according to the actual situation.

[0017] It should also be understood that the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. As used in the specification of this application and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms.

[0018] It should be further understood that the term "and / or" used in the specification of this application and the appended claims refers to any combination and all possible combinations of one or more of the related listed items, and includes these combinations.

[0019] The following will, with reference to the accompanying drawings, elaborate on some embodiments of this application. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0020] Please refer to Figure 1 , Figure 1 , which is a schematic flow diagram of the model predictive control method for a PWM rectifier provided by an embodiment of this application. The PWM rectifier is used for a charging pile. As Figure 1 shown, the model predictive control method for the PWM rectifier provided by the embodiment of this application includes steps S1 to S5.

[0021] Step S1: In response to the charging request of the electric vehicle, obtain the initial battery capacity of the battery of the electric vehicle.

[0022] It should be noted that the execution subject of the embodiment of this application can be a server or a model predictive control system of a PWM rectifier. The following will take the server as an example for illustration.

[0023] Specifically, when the charging interface of the electric vehicle is connected to the charging pile, the server responds to the charging request of the electric vehicle and obtains the initial battery capacity of the battery of the electric vehicle through the battery capacity display unit of the electric vehicle. For example, if the battery capacity displayed by the battery capacity display unit of the electric vehicle is 15%, the server obtains the initial battery capacity of the battery of the electric vehicle as 15%.

[0024] Step S2: Obtain the standard charging voltage control curve of the electric vehicle and the standard battery capacity change curve during the charging process in the database, and generate the charging voltage control curve of the electric vehicle based on the standard charging voltage control curve, the standard battery capacity change curve, and the initial battery capacity.

[0025] Specifically, the server controls a preset camera device to obtain the license plate image of the electric vehicle, obtains the license plate number of the electric vehicle based on the license plate image, and matches a target folder in the database based on the license plate number. The target folder is provided with the standard charging voltage control curve and the standard battery capacity change curve. The abscissa of the standard charging voltage control curve represents time, and the ordinate represents the charging voltage. The abscissa of the standard battery capacity change curve represents time, and the ordinate represents the battery capacity. Taking the charging time point corresponding to the initial battery capacity on the standard battery capacity change curve and the charging time point corresponding to it on the standard charging voltage control curve as the starting point of the charging voltage control curve, and taking the last point of the standard charging voltage control curve as the end point of the charging voltage control curve, intercept the charging voltage control curve on the standard charging voltage control curve. Among them, the standard charging voltage control curve is a charging voltage control curve obtained through experiments to enable the battery of the electric vehicle to have the maximum charging rate in a safe state.

[0026] Step S3: Determine the charging duration corresponding to the charging voltage control curve, and determine the charging time period of the electric vehicle based on a preset delay duration and the charging duration.

[0027] For example, if the charging duration corresponding to the charging voltage control curve is 20 min, the delay duration is 10 s, and the current time is PM5:00:00, then the charging time period is PM5:00:10~PM5:20:10.

[0028] It can be understood that by setting the delay duration in step S3, it helps to prevent the battery of the electric vehicle from being charged before the PWM signal control model described below is generated, and helps to further improve the safety of the charging process.

[0029] Step S4: Predict the input voltage change information of the PWM rectifier during the charging time period to obtain the predicted input voltage change information of the PWM rectifier during the charging time period.

[0030] Specifically, step S4 includes the following steps: Obtain the historical input voltage change curve information of the PWM rectifier during the charging time period; among them, the historical input voltage change curve information includes multiple historical input voltage change curves; for example, if the charging time period is PM5:00:10~PM5:20:10, then the historical input voltage change curve information includes the historical input voltage change curves corresponding to multiple dates before the current date during the time period of PM5:00:10~PM5:20:10; Plot each of the historical input voltage change curves in the same rectangular coordinate system; the abscissa of the rectangular coordinate system represents time, and the ordinate represents the input voltage; In the rectangular coordinate system, segment the charging time period at a time interval of 0.1 ms to obtain a plurality of time points; For each of the time points, determine the maximum input voltage among the input voltage values corresponding to each of the historical input voltage change curves at the time point as the input voltage prediction value corresponding to the time point; Generate the input voltage change prediction information based on the input voltage prediction values corresponding to each of the time points.

[0031] Step S5: Generate a PWM signal control model corresponding to the PWM rectifier during the charging time period based on the charging voltage control curve and the input voltage change prediction information, and control the PWM rectifier during the charging time period based on the PWM signal control model.

[0032] Specifically, the generating a PWM signal control model corresponding to the PWM rectifier during the charging time period based on the charging voltage control curve and the input voltage change prediction information includes the following steps: For each of the time points, determine the charging voltage corresponding to the time point on the charging voltage control curve, and determine the PWM duty cycle corresponding to the time point based on the charging voltage corresponding to the time point and the input voltage prediction value; specifically, divide the charging voltage corresponding to the time point by the input voltage prediction value corresponding to the time point to obtain the PWM duty cycle corresponding to the time point; it can be understood that since the input voltage prediction value corresponding to the time point is the maximum input voltage among the input voltage values corresponding to each of the historical input voltage change curves at the time point, therefore, the duty cycle corresponding to the time point is most likely the minimum duty cycle among the duty cycles that may match the charging voltage corresponding to the time point and can ensure the charging efficiency of the battery. Using this method to determine the duty cycle corresponding to the time point can prevent the battery from overcharging during the charging process while ensuring the charging efficiency of the battery; Generate a PWM duty cycle change curve during the charging time period based on the PWM duty cycles corresponding to each of the time points; the PWM duty cycle change curve is the PWM signal control model.

[0033] The method provided in this embodiment can effectively avoid the problem of battery overcharging caused by the delay in generating the PWM control signal by predicting the PWM signal control model during the charging process before charging the electric vehicle, which helps to improve the safety during the charging process.

[0034] In some embodiments, after the electric vehicle is fully charged during the charging period based on the PWM signal control model, the method further includes: Obtaining the battery capacity of the electric vehicle and determining whether the battery capacity is greater than a preset battery capacity; If not, repeat the steps of generating the charging voltage control curve of the electric vehicle based on the standard charging voltage control curve, the standard battery capacity change curve, and the initial battery capacity and subsequent steps until the battery capacity is greater than the preset battery capacity; it can be understood that when repeating the steps of generating the charging voltage control curve of the electric vehicle based on the standard charging voltage control curve, the standard battery capacity change curve, and the initial battery capacity and subsequent steps, the initial battery capacity is replaced with the battery capacity of the electric vehicle obtained before each repetition; If so, sending a prompt message indicating that the charging is completed to the user of the electric vehicle.

[0035] The method provided in this embodiment helps to ensure that the battery of the electric vehicle is fully charged and the capacitance after the battery charging is completed.

[0036] In some embodiments, obtaining the standard charging voltage control curve of the electric vehicle and the standard battery capacity change curve during the charging process in the database includes the following steps: Controlling a preset camera device to obtain the license plate image of the electric vehicle and obtaining the license plate number of the electric vehicle based on the license plate image; Generating a decryption password based on the license plate number; Simultaneously decrypting each encrypted folder in the database based on the decryption password and determining the encrypted folder with successful decryption as the target encrypted folder; the target encrypted folder is provided with texts corresponding to multiple life stages of the battery; Obtaining the remaining life of the battery and determining the target text in the target encrypted folder based on the remaining life; the target text is provided with the standard charging voltage control curve and the standard battery capacity change curve.

[0037] In this embodiment, generating the decryption password based on the license plate number includes: Determining whether there are Chinese characters in the license plate number; If there are Chinese characters, replacing the Chinese characters in the license plate number with a pinyin sequence and deleting the special characters in the license plate number to obtain a character sequence; If there are no Chinese characters, deleting the special characters in the license plate number to obtain a character sequence; Determine that the numerical value corresponding to the number of digits in the character sequence is the first target numerical value, and determine that the numerical value corresponding to the number of letters in the character sequence is the second target numerical value; Obtain a preset coding algorithm matrix in the database; each position of the coding algorithm matrix is provided with a coding algorithm; Based on the first target numerical value and the second target numerical value, determine a first target coding algorithm in the coding algorithm matrix; the numerical value corresponding to the row number of the position where the first target coding algorithm is located is the same as the first target numerical value, and the numerical value corresponding to the column number of the position where the first target coding algorithm is located is the same as the second target numerical value; Based on the first target coding algorithm, perform coding processing on each letter in the character sequence to obtain a coding sequence corresponding to each letter; For each digit in the character sequence, obtain the sum of squares corresponding to the digit, and based on the digit and the sum of squares corresponding to the digit, determine a second target coding algorithm corresponding to the digit in the coding algorithm matrix, and perform coding processing on the digit based on the second target coding algorithm to obtain a coding sequence corresponding to the digit; wherein, the numerical value corresponding to the row number of the position where the second target coding algorithm is located is the same as the digit, and the numerical value corresponding to the column number of the position where the second target coding algorithm is located is the same as the sum of squares; Based on the positions of the characters corresponding to each coding sequence in the character sequence, arrange each coding sequence in sequence to obtain the decryption password.

[0038] The method provided in this embodiment can prevent the standard charging voltage control curve and the standard battery capacity change curve from being tampered with, thereby ensuring the safety of the electric vehicle during the charging process.

[0039] Please refer to Figure 2 , Figure 2 is a schematic structural block diagram of a model predictive control system 100 of a PWM rectifier provided in an embodiment of the present application. The PWM rectifier is used for a charging pile, such as Figure 2 As shown, the model predictive control system 100 of the PWM rectifier provided in an embodiment of the present application includes: An acquisition module 110, configured to respond to a charging request of an electric vehicle and acquire an initial battery capacity of the battery of the electric vehicle.

[0040] A generation module 120, configured to obtain the standard charging voltage control curve of the electric vehicle and the standard battery capacity change curve during the charging process in a database, and generate a charging voltage control curve of the electric vehicle based on the standard charging voltage control curve, the standard battery capacity change curve and the initial battery capacity.

[0041] A determination module 130, configured to determine the charging duration corresponding to the charging voltage control curve, and determine the charging time period of the electric vehicle based on a preset delay duration and the charging duration.

[0042] A prediction module 140, configured to predict the input voltage change information of the PWM rectifier during the charging time period, and obtain the predicted input voltage change information of the PWM rectifier during the charging time period.

[0043] A control module 150, configured to generate a PWM signal control model corresponding to the PWM rectifier during the charging time period based on the charging voltage control curve and the predicted input voltage change information, and control the PWM rectifier during the charging time period based on the PWM signal control model.

[0044] It should be noted that those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the above-described system and each module can refer to the processes in the foregoing embodiments of the model predictive control method of the PWM rectifier, and will not be described herein again.

[0045] The model predictive control system 100 of the PWM rectifier provided in the foregoing embodiment can be implemented in the form of a computer program, and this computer program can run on a Figure 3 terminal device 200 as shown.

[0046] Please refer to Figure 3 , Figure 3 , which is a schematic block diagram of the structure of the terminal device 200 provided in the embodiment of the present application. The terminal device 200 includes a processor 201 and a memory 202. The processor 201 and the memory 202 are connected through a device bus 203. Among them, the memory 202 may include a non-volatile storage medium and an internal memory.

[0047] The non-volatile storage medium can store a computer program. This computer program includes program instructions. When the program instructions are executed by the processor 201, the processor 201 can be made to execute any of the above model predictive control methods of the PWM rectifier.

[0048] The processor 201 is configured to provide computing and control capabilities to support the operation of the entire terminal device 200.

[0049] The internal memory provides an environment for the operation of the computer program in the non-volatile storage medium. When the computer program is executed by the processor 201, the processor 201 can be made to execute any of the above model predictive control methods of the PWM rectifier.

[0050] Those skilled in the art can understand, Figure 3The structure shown is only a block diagram of some structures related to the solution of this application, and does not constitute a limitation on the terminal device 200 involved in the solution of this application. Specifically, the terminal device 200 may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements.

[0051] It should be understood that the processor 201 may be a central processing unit (CPU), and the processor 201 may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Among them, the general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0052] Among them, in some embodiments, the processor 201 is used to run a computer program stored in the memory to implement the following steps: In response to the charging request of the electric vehicle, obtain the initial battery capacity of the battery of the electric vehicle; Obtain the standard charging voltage control curve of the electric vehicle and the standard battery capacity change curve during the charging process in the database, and generate the charging voltage control curve of the electric vehicle based on the standard charging voltage control curve, the standard battery capacity change curve and the initial battery capacity; Determine the charging duration corresponding to the charging voltage control curve, and determine the charging time period of the electric vehicle based on the preset delay duration and the charging duration; Predict the input voltage change information of the PWM rectifier during the charging time period to obtain the predicted input voltage change information of the PWM rectifier during the charging time period; Generate a PWM signal control model corresponding to the PWM rectifier during the charging time period based on the charging voltage control curve and the predicted input voltage change information, and control the PWM rectifier during the charging time period based on the PWM signal control model.

[0053] It should be noted that those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working process of the terminal device 200 described above can refer to the corresponding process of the model predictive control method of the foregoing PWM rectifier, which will not be elaborated here.

[0054] An embodiment of the present application further provides a computer-readable storage medium storing a computer program, which, when executed by one or more processors, causes the one or more processors to implement the model predictive control method of the PWM rectifier provided by the embodiment of the present application.

[0055] Among them, the computer-readable storage medium may be an internal storage unit of the terminal device 200 in the foregoing embodiment, such as the hard disk or memory of the terminal device 200. The computer-readable storage medium may also be an external storage device of the terminal device 200, such as a plug-in hard disk equipped with the terminal device 200, a Smart Media Card (SMC), a Secure Digital (SD) card, a Flash Card, etc.

[0056] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A model predictive control method for a PWM rectifier, characterized in that, The PWM rectifier is used for a charging pile, and the method includes: In response to a charging request of an electric vehicle, obtaining an initial battery capacity of the battery of the electric vehicle; Obtaining a standard charging voltage control curve of the electric vehicle and a standard battery capacity change curve during the charging process in a database, and generating a charging voltage control curve of the electric vehicle based on the standard charging voltage control curve, the standard battery capacity change curve, and the initial battery capacity; Determining a charging duration corresponding to the charging voltage control curve, and determining a charging time period of the electric vehicle based on a preset delay duration and the charging duration; Predicting input voltage change information of the PWM rectifier during the charging time period to obtain input voltage change prediction information of the PWM rectifier during the charging time period; Generating a PWM signal control model corresponding to the PWM rectifier during the charging time period based on the charging voltage control curve and the input voltage change prediction information, and controlling the PWM rectifier during the charging time period based on the PWM signal control model.

2. The model predictive control method of the PWM rectifier according to claim 1, characterized in that, The predicting the input voltage change information of the PWM rectifier during the charging time period to obtain the input voltage change prediction information of the PWM rectifier during the charging time period includes: Obtaining historical input voltage change curve information of the PWM rectifier during the charging time period; wherein, the historical input voltage change curve information includes a plurality of historical input voltage change curves; Plotting each of the historical input voltage change curves in the same rectangular coordinate system; the abscissa of the rectangular coordinate system represents time, and the ordinate represents the input voltage; Performing segmentation processing on the charging time period at a time interval of 0.1 ms in the rectangular coordinate system to obtain a plurality of time points; For each of the time points, determining the maximum input voltage among the input voltage values corresponding to each of the historical input voltage change curves at the time point as the input voltage prediction value corresponding to the time point; Generating the input voltage change prediction information based on the input voltage prediction values corresponding to each of the time points.

3. The model predictive control method of the PWM rectifier according to claim 2, characterized in that, The generating the PWM signal control model corresponding to the PWM rectifier during the charging time period based on the charging voltage control curve and the input voltage change prediction information includes: For each of the time points, determining the charging voltage corresponding to the time point on the charging voltage control curve, and determining the PWM duty cycle corresponding to the time point based on the charging voltage corresponding to the time point and the input voltage prediction value; Generating a PWM duty cycle change curve during the charging time period based on the PWM duty cycles corresponding to each of the time points; the PWM duty cycle change curve is the PWM signal control model.

4. The model predictive control method for the PWM rectifier according to claim 1, characterized in that After completing the charging of the electric vehicle based on the PWM signal control model during the charging time period, the method further includes: Obtaining the battery capacity of the electric vehicle, and determining whether the battery capacity is greater than a preset battery capacity; If not, repeat the steps of generating the charging voltage control curve of the electric vehicle based on the standard charging voltage control curve, the standard battery capacity change curve, and the initial battery capacity and subsequent steps until the battery capacity is greater than the preset battery capacity; If so, send a charging completion prompt message to the user of the electric vehicle.

5. The model predictive control method of the PWM rectifier according to claim 1, wherein The obtaining of the standard charging voltage control curve of the electric vehicle and the standard battery capacity change curve during charging in the database includes: Controlling a preset camera device to obtain the license plate image of the electric vehicle, and obtaining the license plate number of the electric vehicle based on the license plate image; Generating a decryption password based on the license plate number; Simultaneously decrypting each encrypted folder in the database based on the decryption password, and determining the encrypted folder with successful decryption as the target encrypted folder; the target encrypted folder has texts corresponding to multiple life stages of the battery; Obtaining the remaining life of the battery, and determining the target text in the target encrypted folder based on the remaining life; the target text has the standard charging voltage control curve and the standard battery capacity change curve.

6. The model predictive control method for the PWM rectifier according to claim 5, wherein The generating of the decryption password based on the license plate number includes: Judging whether there are Chinese characters in the license plate number; If there are Chinese characters, replacing the Chinese characters in the license plate number with a pinyin sequence and deleting the special characters in the license plate number to obtain a character sequence; If there are no Chinese characters, deleting the special characters in the license plate number to obtain a character sequence; Determining the value corresponding to the number of digits in the character sequence as the first target value, and determining the value corresponding to the number of letters in the character sequence as the second target value; Obtaining a preset coding algorithm matrix in the database; Determining a first target coding algorithm in the coding algorithm matrix based on the first target value and the second target value; the value corresponding to the row number where the first target coding algorithm is located is the same as the first target value, and the value corresponding to the column number where the first target coding algorithm is located is the same as the second target value; Performing coding processing on each letter in the character sequence based on the first target coding algorithm to obtain a coding sequence corresponding to each letter; For each digit in the character sequence, obtaining the sum of squares corresponding to the digit, and determining the second target coding algorithm corresponding to the digit in the coding algorithm matrix based on the digit and the sum of squares corresponding to the digit, and performing coding processing on the digit based on the second target coding algorithm to obtain the coding sequence corresponding to the digit; wherein, the value corresponding to the row number where the second target coding algorithm is located is the same as the digit, and the value corresponding to the column number where the second target coding algorithm is located is the same as the sum of squares; Arranging each coding sequence in sequence based on the position of the character corresponding to each coding sequence in the character sequence to obtain the decryption password.

7. A model predictive control system for a PWM rectifier, characterized in that, The PWM rectifier is used for a charging pile, and the system includes: An obtaining module, configured to obtain the initial battery capacity of the battery of the electric vehicle in response to a charging request of the electric vehicle; A generation module, configured to obtain the standard charging voltage control curve of the electric vehicle and the standard battery capacity change curve during charging in a database, and generate the charging voltage control curve of the electric vehicle based on the standard charging voltage control curve, the standard battery capacity change curve, and the initial battery capacity; A determination module, configured to determine the charging duration corresponding to the charging voltage control curve, and determine the charging time period of the electric vehicle based on a preset delay duration and the charging duration; A prediction module, configured to predict the input voltage change information of the PWM rectifier during the charging time period to obtain the predicted input voltage change information of the PWM rectifier during the charging time period; A control module, configured to generate a PWM signal control model corresponding to the PWM rectifier during the charging time period based on the charging voltage control curve and the predicted input voltage change information, and control the PWM rectifier during the charging time period based on the PWM signal control model.

Images