A converter intelligent control method and system

Abstract

The present invention relates to the field of voltage regulation technology, and specifically discloses a converter intelligent regulation method and system, the method comprising the following steps: S1: determining the output voltage corresponding to different duty cycles, generating coordinate points according to the average output voltage, and fitting the coordinate points to obtain a fitting curve; S2: determining the theoretical duty cycle according to the fitting curve and the theoretical output voltage, adjusting the duty cycle to the theoretical duty cycle; calculating the voltage difference according to the actual output voltage, and determining whether it is an abnormal state; S3: determining the duty cycle adjustment value, determining the adjustment range according to the average duty cycle adjustment value; adjusting the actual duty cycle according to the adjustment range and the theoretical duty cycle until the corresponding voltage difference meets expectations. The present invention reduces the impact of component aging on the output voltage by compensating for the duty cycle, thereby ensuring that the converter can work stably and ensuring the stability of its output voltage.

Description

Technical Field

[0001] The present invention relates to the technical field of voltage regulation, and in particular to a converter intelligent regulation method and system. Background Art

[0002] A converter is an electrical device that is mainly used to change the characteristics of current or voltage to adapt to different power requirements. During the charging process of an electric vehicle battery, the battery voltage of the electric vehicle changes as the charging process progresses. At the beginning of charging, the battery voltage is low, and when it is close to full, the battery voltage is high. In order to maintain a stable charging process, the converter needs to adjust the duty cycle according to the battery voltage change to provide a suitable charging voltage.

[0003] However, as the converter is used for a longer period of time, it will inevitably age, resulting in degradation of the performance of internal components such as switching elements, filter capacitors, inductors, etc. These changes may result in the output voltage not being able to accurately or stably reach the expected target when adjusting the duty cycle, although the duty cycle has reached the expected value due to component aging. Summary of the invention

[0004] The purpose of the present invention is to provide a converter intelligent control method and system to solve the following technical problems:

[0005] As the converter is used for a long time, it will inevitably age, resulting in degradation of the performance of internal components such as switching elements, filter capacitors, inductors, etc. These changes may result in the output voltage not being able to accurately or stably reach the expected target when adjusting the duty cycle, although the duty cycle has reached the expected value due to component aging.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A converter intelligent control method comprises the following steps:

[0008] S1: Divide the design life of the converter into a number of life segments at preset time intervals, and select m converters whose usage time belongs to the same life segment as target converters, where m is a preset number;

[0009] For a single target converter, determine the output voltage corresponding to different duty cycles x, calculate the average output voltage corresponding to the same duty cycle, and generate a coordinate point (a, V a ), V a represents the average output voltage when the duty cycle is a, and the coordinate points are fitted to obtain a fitting curve;

[0010] S2: Determine the life span i corresponding to the converter, and determine the fitting curve f corresponding to the life span i i (x), determine the theoretical output voltage V of the converter within the preset first monitoring period The , the theoretical output voltage V The Substituting into the fitting curve f i (x), and get the theoretical duty cycle X The , in the first monitoring period, adjusting the duty cycle of the converter to the theoretical duty cycle X The ;

[0011] Get the actual output voltage V Act , calculate the voltage difference ΔV=V The -V Act , when the voltage difference ΔV≥ΔVys, it is marked as an abnormal state, and ΔVys represents a preset voltage difference threshold;

[0012] S3: Set the second monitoring period and determine the duty cycle adjustment value Δx=XSJ sec -XS The ,XSJ sec represents the actual duty cycle when the voltage difference is less than the voltage difference threshold value during the second monitoring period, XS The represents the theoretical duty cycle in the second monitoring period, calculates the average duty cycle adjustment value Δxsj, sets the adjustment range [Δxsj-Δxsj', Δxsj+Δxsj'], Δxsj' represents the preset duty cycle correction value;

[0013] Let the actual duty cycle XF in the first monitoring period be The =X The +Y, Y∈[Δxsj-Δxsj', Δxsj+Δxsj'], adjust the value of Y from low to high within the adjustment range at a preset duty cycle interval and determine the voltage difference until the corresponding voltage difference after a certain adjustment of the value of Y is less than the voltage difference threshold.

[0014] As a further solution of the present invention: the step S3 further includes the following steps:

[0015] Determine the minimum voltage difference ΔV min =min(ΔVJH),ΔVJH=(ΔVS 1 , ΔVS 2 , …, ΔVS n ), n represents the total number of target values, the target value is the value of Y when the voltage difference is less than the voltage difference threshold, ΔVS n Indicates the voltage difference corresponding to the nth target value;

[0016] Determine the minimum voltage difference ΔVmin The corresponding value of Y min , let the duty cycle of the converter be adjusted to X during the first monitoring period The +Y min .

[0017] As a further solution of the present invention: in the step S1, during the process of calculating the average output voltage, when the difference between the output voltage b and the average output voltage is greater than or equal to a preset value, the output voltage b is removed and the average output voltage is calculated again.

[0018] As a further solution of the present invention: when the total number mys of output voltages corresponding to the average output voltage is less than a preset number threshold, m-mys target converters are determined again, and the average output voltage is calculated.

[0019] As a further solution of the present invention: in step S3, the actual duty cycle XF is adjusted The During the process, the actual duty cycle XF The Belongs to the preset duty cycle range.

[0020] As a further solution of the present invention: when the actual duty cycle XF The When the voltage difference cannot be made smaller than the voltage difference threshold within the duty cycle range, a warning message is sent to give an alarm.

[0021] A converter intelligent control system, applied to a converter intelligent control method, includes: a calibration module, an initial adjustment module and an adjustment optimization module, specifically:

[0022] Calibration module: divide the design life of the converter into several life segments at preset time intervals, and take m converters whose usage time belongs to the same life segment as target converters, where m is a preset number;

[0023] For a single target converter, determine the output voltage corresponding to different duty cycles x, calculate the average output voltage corresponding to the same duty cycle, and generate a coordinate point (a, V a ), V a represents the average output voltage when the duty cycle is a, and the coordinate points are fitted to obtain a fitting curve;

[0024] Initial adjustment module: determine the life segment i corresponding to the converter, and determine the fitting curve f corresponding to the life segment i i (x), determine the theoretical output voltage V of the converter within the preset first monitoring period The , the theoretical output voltage V The Substituting into the fitting curve f i (x), and get the theoretical duty cycle X The, in the first monitoring period, adjusting the duty cycle of the converter to the theoretical duty cycle X The ;

[0025] Get the actual output voltage V Act , calculate the voltage difference ΔV=V The -V Act , when the voltage difference ΔV≥ΔVys, it is marked as an abnormal state, and ΔVys represents a preset voltage difference threshold;

[0026] Adjustment and optimization module: set the second monitoring period and determine the duty cycle adjustment value Δx=XSJ sec -XS The ,XSJ sec represents the actual duty cycle when the voltage difference is less than the voltage difference threshold value during the second monitoring period, XS The represents the theoretical duty cycle in the second monitoring period, calculates the average duty cycle adjustment value Δxsj, sets the adjustment range [Δxsj-Δxsj', Δxsj+Δxsj'], Δxsj' represents the preset duty cycle correction value;

[0027] Let the actual duty cycle XF in the first monitoring period be The =X The +Y, Y∈[Δxsj-Δxsj', Δxsj+Δxsj'], adjust the value of Y from low to high within the adjustment range at a preset duty cycle interval and determine the voltage difference until the corresponding voltage difference after a certain adjustment of the value of Y is less than the voltage difference threshold.

[0028] Beneficial effects of the present invention: In this solution, the life of the converter is divided into multiple time periods, and a group of "target converters" is selected in each time period, that is, converters in the same life period, so as to better understand the changes in their performance over time; by measuring the output voltage under different duty cycles and calculating its average output voltage, the corresponding coordinate points are generated. These coordinate points are fitted to obtain a fitting curve, which describes the relationship between the duty cycle and the output voltage. The fitting curve provides a theoretical basis for subsequent monitoring and adjustment, and can help adjust the duty cycle according to the output voltage requirements (that is, the theoretical output voltage) during the actual operation process, so that the output voltage meets the requirements; thereafter, the theoretical duty cycle is determined according to the theoretical output voltage, and after adjusting the duty cycle to the theoretical duty cycle, the actual output voltage is detected to see whether it meets expectations. If the actual output voltage deviates from the theoretical voltage, the duty cycle needs to be further adjusted. Ensure the stability and reliability of the output voltage; finally, in the second monitoring cycle, further monitor the difference between the actual duty cycle and the theoretical duty cycle, and reduce the voltage difference by adjusting the duty cycle, calculate an average duty cycle adjustment value Δxsj, and set an adjustment range [Δxsj-Δxsj', Δxsj+Δxsj']. By gradually adjusting Y within this range, find the actual duty cycle that can make the voltage difference less than the threshold. In this step, by fine-tuning the duty cycle, the output voltage of the converter can be closer to the theoretical value, thereby compensating for the performance changes caused by aging to ensure the stability of the output voltage. By monitoring and adjusting in different time periods, the impact of component aging on the output voltage is compensated, thereby ensuring that the converter can work stably, reducing the performance degradation caused by aging, and ensuring its output voltage stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be further described below in conjunction with the accompanying drawings.

[0030] Figure 1 It is a flow chart of a converter intelligent control method of the present invention. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions 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 are within the scope of protection of the present invention.

[0032] See also Figure 1 As shown, the present invention is a converter intelligent control method, comprising the following steps:

[0033] S1: Divide the design life of the converter into a number of life segments at preset time intervals, and select m converters whose usage time belongs to the same life segment as target converters, where m is a preset number;

[0034] For a single target converter, determine the output voltage corresponding to different duty cycles x, calculate the average output voltage corresponding to the same duty cycle, and generate a coordinate point (a, V a ), V a represents the average output voltage when the duty cycle is a, and the coordinate points are fitted to obtain a fitting curve;

[0035] S2: Determine the life span i corresponding to the converter, and determine the fitting curve f corresponding to the life span i i (x), determine the theoretical output voltage V of the converter within the preset first monitoring period The , the theoretical output voltage V The Substituting into the fitting curve f i (x), and get the theoretical duty cycle X The , in the first monitoring period, adjusting the duty cycle of the converter to the theoretical duty cycle X The ;

[0036] Get the actual output voltage V Act , calculate the voltage difference ΔV=V The -V Act , when the voltage difference ΔV≥ΔVys, it is marked as an abnormal state, and ΔVys represents a preset voltage difference threshold;

[0037] S3: Set the second monitoring period and determine the duty cycle adjustment value Δx=XSJ sec -XS The ,XSJ sec represents the actual duty cycle when the voltage difference is less than the voltage difference threshold value during the second monitoring period, XS The represents the theoretical duty cycle in the second monitoring period, calculates the average duty cycle adjustment value Δxsj, sets the adjustment range [Δxsj-Δxsj', Δxsj+Δxsj'], Δxsj' represents the preset duty cycle correction value;

[0038] Let the actual duty cycle XF in the first monitoring period be The =X The +Y, Y∈[Δxsj-Δxsj', Δxsj+Δxsj'], adjust the value of Y from low to high within the adjustment range at a preset duty cycle interval and determine the voltage difference until the corresponding voltage difference after a certain adjustment of the value of Y is less than the voltage difference threshold.

[0039] It should be noted that the life of the converter is divided into multiple time periods, and a group of "target converters" is selected in each time period, that is, converters in the same life period, so as to better understand the changes in their performance over time; by measuring the output voltage under different duty cycles and calculating its average output voltage, the corresponding coordinate points are generated. These coordinate points are fitted to obtain a fitting curve, which describes the relationship between the duty cycle and the output voltage. The fitting method adopts nonlinear fitting, which belongs to the prior art and will not be repeated here. The fitting curve provides a theoretical basis for subsequent monitoring and adjustment, which can help adjust the duty cycle according to the output voltage requirements (that is, the theoretical output voltage) during the actual operation process, so that the output voltage meets the requirements; then, the theoretical duty cycle is determined according to the theoretical output voltage, and after adjusting the duty cycle to the theoretical duty cycle, the actual output voltage is detected to see whether it meets the expectations. If the actual output voltage deviates from the theoretical voltage, the duty cycle needs to be further adjusted. Ensure the stability and reliability of the output voltage; finally, in the second monitoring cycle, further monitor the difference between the actual duty cycle and the theoretical duty cycle, and reduce the voltage difference by adjusting the duty cycle, calculate an average duty cycle adjustment value Δxsj, and set an adjustment range [Δxsj-Δxsj', Δxsj+Δxsj']. By gradually adjusting Y within this range, find the actual duty cycle that can make the voltage difference less than the threshold. In this step, by fine-tuning the duty cycle, the output voltage of the converter can be closer to the theoretical value, thereby compensating for the performance changes caused by aging to ensure the stability of the output voltage.

[0040] In another preferred implementation of the present invention, the step S3 further includes the following steps:

[0041] Determine the minimum voltage difference ΔV min =min(ΔVJH),ΔVJH=(ΔVS 1 , ΔVS 2 , …, ΔVS n ), n represents the total number of target values, the target value is the value of Y when the voltage difference is less than the voltage difference threshold, ΔVS n Indicates the voltage difference corresponding to the nth target value;

[0042] Determine the minimum voltage difference ΔV min The corresponding value of Y min , let the duty cycle of the converter be adjusted to X during the first monitoring period The +Y min .

[0043] It is worth noting that the voltage difference is minimized by optimizing the duty cycle adjustment. By calculating multiple adjusted voltage difference values, the duty cycle adjustment value Y corresponding to the minimum voltage difference is selected. min, and based on this adjustment value, the duty cycle is corrected to ensure that the output voltage of the converter is always as close to the theoretical value as possible, thereby improving the stability of the system and being able to more effectively compensate for performance changes in the event of component aging.

[0044] In another preferred implementation of the present invention, in the step S1, during the process of calculating the average output voltage, when the difference between the output voltage b and the average output voltage is greater than or equal to a preset value, the output voltage b is removed and the average output voltage is calculated again.

[0045] It is understandable that the screening of outliers is added when calculating the average output voltage to ensure that the calculation results are more accurate; by removing those output voltages that are greatly different from other values, the influence of abnormal data on the results is avoided, and the reliability of subsequent fitting and adjustment processes is improved.

[0046] In another preferred implementation of the present invention, when the total number mys of output voltages corresponding to the average output voltage is less than a preset number threshold, m-mys target converters are determined again, and the average output voltage is calculated.

[0047] It should be noted that ensuring that the amount of data reaches the preset threshold when calculating the average output voltage further improves the accuracy and stability of the calculation; when the existing data is insufficient, new target converter data is selected and supplemented to ensure that the final calculated average output voltage is more reliable, thereby providing a more solid basis for subsequent converter adjustment and monitoring.

[0048] In another preferred implementation of the present invention, in step S3, the actual duty cycle XF is adjusted. The During the process, the actual duty cycle XF The Belongs to the preset duty cycle range.

[0049] It should be noted that by imposing a range constraint on the actual duty cycle of the adjustment, it is ensured that the duty cycle during the adjustment process is always within the safe operating range of the converter, avoiding instability caused by excessive or small duty cycle, improving the reliability and safety of the system, and providing a more robust foundation for subsequent voltage adjustment and duty cycle correction.

[0050] In another preferred embodiment of the present invention, when the actual duty cycle XF The When the voltage difference cannot be made smaller than the voltage difference threshold within the duty cycle range, a warning message is sent to give an alarm.

[0051] A converter intelligent control system, applied to a converter intelligent control method, includes: a calibration module, an initial adjustment module and an adjustment optimization module, specifically:

[0052] Calibration module: divide the design life of the converter into several life segments at preset time intervals, and take m converters whose usage time belongs to the same life segment as target converters, where m is a preset number;

[0053] For a single target converter, determine the output voltage corresponding to different duty cycles x, calculate the average output voltage corresponding to the same duty cycle, and generate a coordinate point (a, V a ), V a represents the average output voltage when the duty cycle is a, and the coordinate points are fitted to obtain a fitting curve;

[0054] Initial adjustment module: determine the life segment i corresponding to the converter, and determine the fitting curve f corresponding to the life segment i i (x), determine the theoretical output voltage V of the converter within the preset first monitoring period The , the theoretical output voltage V The Substituting into the fitting curve f i (x), and get the theoretical duty cycle X The , in the first monitoring period, adjusting the duty cycle of the converter to the theoretical duty cycle X The ;

[0055] Get the actual output voltage V Act , calculate the voltage difference ΔV=V The -V Act , when the voltage difference ΔV≥ΔVys, it is marked as an abnormal state, and ΔVys represents a preset voltage difference threshold;

[0056] Adjustment and optimization module: set the second monitoring period and determine the duty cycle adjustment value Δx=XSJ sec -XS The ,XSJ sec represents the actual duty cycle when the voltage difference is less than the voltage difference threshold value during the second monitoring period, XS The represents the theoretical duty cycle in the second monitoring period, calculates the average duty cycle adjustment value Δxsj, sets the adjustment range [Δxsj-Δxsj', Δxsj+Δxsj'], Δxsj' represents the preset duty cycle correction value;

[0057] Let the actual duty cycle XF in the first monitoring period be The =X The +Y, Y∈[Δxsj-Δxsj', Δxsj+Δxsj'], adjust the value of Y from low to high within the adjustment range at a preset duty cycle interval and determine the voltage difference until the corresponding voltage difference after a certain adjustment of the value of Y is less than the voltage difference threshold.

[0058] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A converter intelligent control method, characterized in that: The following steps are involved: S1: Divide the design life of the converter into a number of life segments at preset time intervals, and select m converters whose usage time belongs to the same life segment as target converters, where m is a preset number; For a single target converter, determine the output voltage corresponding to different duty cycles x, calculate the average output voltage corresponding to the same duty cycle, and generate a coordinate point (a, V a ), V a represents the average output voltage when the duty cycle is a, and the coordinate points are fitted to obtain a fitting curve; S2: Determine the life span i corresponding to the converter, and determine the fitting curve f corresponding to the life span i i (x), determine the theoretical output voltage V of the converter within the preset first monitoring period The , the theoretical output voltage V The Substituting into the fitting curve f i (x), and get the theoretical duty cycle X The , in the first monitoring period, adjusting the duty cycle of the converter to the theoretical duty cycle X The ; Get the actual output voltage V Act , calculate the voltage difference ΔV=V The -V Act , when the voltage difference ΔV≥ΔVys, it is marked as an abnormal state, and ΔVys represents a preset voltage difference threshold; S3: Set the second monitoring period and determine the duty cycle adjustment value Δx=XSJ sec -XS The ,XSJ sec represents the actual duty cycle when the voltage difference is less than the voltage difference threshold value during the second monitoring period, XS The represents the theoretical duty cycle in the second monitoring period, calculates the average duty cycle adjustment value Δxsj, sets the adjustment range [Δxsj-Δxsj', Δxsj+Δxsj'], Δxsj' represents the preset duty cycle correction value; Let the actual duty cycle XF in the first monitoring period be The =X The +Y, Y∈[Δxsj-Δxsj', Δxsj+Δxsj'], adjust the value of Y from low to high within the adjustment range at a preset duty cycle interval and determine the voltage difference until the corresponding voltage difference after a certain adjustment of the value of Y is less than the voltage difference threshold.

2. A converter intelligent control method according to claim 1, characterized in that: The step S3 further includes the following steps: Determine the minimum voltage difference ΔV min =min(ΔVJH), ΔVJH=(ΔVS1, ΔVS2,…, ΔVS n ), n represents the total number of target values, the target value is the value of Y when the voltage difference is less than the voltage difference threshold, ΔVS n Indicates the voltage difference corresponding to the nth target value; Determine the minimum voltage difference ΔV min The corresponding value of Y min , let the duty cycle of the converter be adjusted to X during the first monitoring period The +Y min .

3. The intelligent control method of a converter according to claim 1, characterized in that: In the step S1, during the process of calculating the average output voltage, when the difference between the output voltage b and the average output voltage is greater than or equal to a preset value, the output voltage b is removed and the average output voltage is calculated again.

4. A converter intelligent control method according to claim 3, characterized in that: When the total number mys of output voltages corresponding to the average output voltage is less than a preset number threshold, m-mys target converters are determined again, and the average output voltage is calculated.

5. The intelligent control method of a converter according to claim 1, characterized in that: In step S3, the actual duty cycle XF is adjusted The During the process, the actual duty cycle XF The Belongs to the preset duty cycle range.

6. A converter intelligent control method according to claim 5, characterized in that: When the actual duty cycle XF The When the voltage difference cannot be made smaller than the voltage difference threshold within the duty cycle range, a warning message is sent to give an alarm.

7. A converter intelligent control system, applied to a converter intelligent control method according to any one of claims 1 to 6, characterized in that: include: Calibration module, initial adjustment module and adjustment optimization module, specifically: Calibration module: divide the design life of the converter into several life segments at preset time intervals, and take m converters whose usage time belongs to the same life segment as target converters, where m is a preset number; For a single target converter, determine the output voltage corresponding to different duty cycles x, calculate the average output voltage corresponding to the same duty cycle, and generate a coordinate point (a, V a ), V a represents the average output voltage when the duty cycle is a, and the coordinate points are fitted to obtain a fitting curve; Initial adjustment module: determine the life segment i corresponding to the converter, and determine the fitting curve f corresponding to the life segment i i (x), determine the theoretical output voltage V of the converter within the preset first monitoring period The , the theoretical output voltage V The Substituting into the fitting curve f i (x), and get the theoretical duty cycle X The , in the first monitoring period, adjusting the duty cycle of the converter to the theoretical duty cycle X The ; Get the actual output voltage V Act , calculate the voltage difference ΔV=V The -V Act , when the voltage difference ΔV≥ΔVys, it is marked as an abnormal state, and ΔVys represents a preset voltage difference threshold; Adjustment and optimization module: set the second monitoring period and determine the duty cycle adjustment value Δx=XSJ sec -XS The ,XSJ sec represents the actual duty cycle when the voltage difference is less than the voltage difference threshold value during the second monitoring period, XS The represents the theoretical duty cycle in the second monitoring period, calculates the average duty cycle adjustment value Δxsj, sets the adjustment range [Δxsj-Δxsj', Δxsj+Δxsj'], Δxsj' represents the preset duty cycle correction value; Let the actual duty cycle XF in the first monitoring period be The =X The +Y, Y∈[Δxsj-Δxsj', Δxsj+Δxsj'], adjust the value of Y from low to high within the adjustment range at a preset duty cycle interval and determine the voltage difference until the corresponding voltage difference after a certain adjustment of the value of Y is less than the voltage difference threshold.

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