Algorithm system for collecting waveform and analyzing behavior based on CP guide circuit

Abstract

The invention provides an algorithm system for collecting waveforms and analyzing behaviors of the waveforms based on a CP guide circuit, and relates to the technical field of electric vehicle alternating current charging, pulse width modulation (PWM) waveform data is collected through the CP guide circuit, and preliminary data screening and filtering processing are carried out, so that a stable and safe charging process is achieved; the system comprises a data acquisition module, a preliminary data screening module, a filtering processing module, an abnormal value judgment module and an application layer judgment module, the data acquisition module accurately captures PWM waveform data of a CP guide circuit, and a basis is provided for system analysis; the preliminary data screening module removes invalid or abnormal data to ensure data quality; the filtering processing module is used for smoothing data through an advanced algorithm, extracting a real duty ratio and enhancing data reliability; the abnormal value judgment module monitors in real time, and charging safety is guaranteed; finally, an application layer judgment module formulates a charging strategy according to accurate data, all modules work cooperatively, and the stability and reliability of the charging system are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of AC charging for electric vehicles, and particularly to an algorithm system for collecting waveforms based on a CP guidance circuit and analyzing its behavior. Background Art

[0002] With the rapid development of new energy technologies, electric vehicles have become an important trend for future transportation. CP (Control Pilot): In the new energy vehicle charging system, the CP signal is the control guidance signal, which is mainly used for communication and control between the charging pile and the electric vehicle. As an important charging facility for electric vehicles, AC charging piles are increasingly widely used. The AC charging pile inputs alternating current into the vehicle through the transmission and determination of the Pulse Width Modulation (PWM) signal, and the On-Board Charger (OBC) in the vehicle performs AC / DC conversion to charge the battery. Compared with DC charging, AC charging is more popular in environments such as homes and communities. Its main advantages are reducing the floor area and the impact on the power grid, and at the same time reducing the charging cost for vehicle owners.

[0003] However, in the prior art, the AC charging system has certain defects and deficiencies, which are mainly manifested in the following aspects: (1) The output signal of the charging pile has jitter, resulting in misjudgment by the vehicle to stop charging; (2) The signal collected by the vehicle is inaccurate, causing the charging to stop; (3) External interference leads to signal jitter, resulting in abnormal charging stop.

[0004] In view of the above problems, the present invention proposes an algorithm system for collecting waveforms based on a CP guidance circuit and analyzing its behavior. This system is mainly applied when the vehicle is charging at an AC charging pile, for quickly determining the normal waveform and parameter transmission, verifying the authenticity of the abnormal waveform, and performing filtering processing or abnormal processing, so as to ensure that the vehicle can charge in a stable and safe manner. Summary of the Invention

[0005] To achieve the above object, the technical solution adopted by the present invention is: An algorithm system for collecting waveforms based on a CP guidance circuit and analyzing its behavior, comprising: A data acquisition module, a preliminary data screening module, a filtering processing module, an outlier determination module, and an application layer determination module; The data acquisition module includes a hardware circuit for real-time collecting Pulse Width Modulation (PWM) waveform data from the CP guidance circuit; The PWM waveform is a common signal form during the charging process of electric vehicles, and its duty cycle directly reflects the charging power or status. High-frequency (such as 1KHz) acquisition can more accurately capture waveform changes and provide rich information for analysis.

[0006] The preliminary data screening module is used for preliminarily screening the collected data; The filtering processing module is used to perform a quick sort on the filtered data and take the median as the true duty cycle, improving the stability and reliability of the data.

[0007] The outlier determination module is used to monitor the abnormal conditions of the collected data through a timer, make an outlier determination based on the monitoring results, and trigger corresponding processing procedures; setting the timer and continuously monitoring the data can identify persistent abnormal data patterns within a short period of time. Once determined to be abnormal, corresponding processing procedures such as stopping charging and alarming are immediately triggered to ensure the safety of the charging process. At the same time, for non-persistent abnormalities, by resetting the timer and re-collecting the data, the possibility of misjudgment can be reduced.

[0008] The application layer determination module is used to make charging control decisions based on the true duty cycle data provided by the filtering processing module. The duty cycle data directly reflects the changing trend of the charging power and status. The application layer determination module adjusts charging parameters such as current and voltage according to these data to match the actual needs and charging conditions of the electric vehicle. At the same time, it can also take safety measures in a timely manner according to the feedback of the outlier determination module to ensure the safety and reliability of the charging process.

[0009] Preferably, in the data acquisition module, the acquisition frequency is set to 1KHz, corresponding to a pulse width modulation (PWM) waveform period of 1ms. The duty cycle data is acquired, and 11 groups of data are continuously acquired according to the set period; among them, the calculation formula for the duty cycle D is: ; In the formula: Ton represents the duration of the high level in the pulse signal, T represents the complete period of the pulse signal, D represents the duty cycle, which is a percentage value representing the proportion of the time occupied by the high level within one cycle.

[0010] Preferably, in the preliminary data screening of the preliminary data screening module for the collected data, the preliminary screening is as follows: When 3 or more rising edges or falling edges are collected within one pulse period, it is determined that this group of data is invalid; When the ratio of the duration of the pulse high level to the pulse period is greater than 1 or less than 0, it is also determined that this group of data is invalid.

[0011] Preferably, in the filtering processing module, First, perform a quick sort algorithm on the 11 groups of data collected by the data acquisition module, sort them from small to large and take the median, and store the median as the temporary value of the first duty cycle; Judge whether the temporary value of the first duty cycle meets the preset range X; Repeat the data acquisition and sorting process to obtain another temporary value, the second duty cycle, and determine whether it meets the range X; If the absolute value of the difference between the temporary value of the first duty cycle and the temporary value of the second duty cycle is less than or equal to 2%, then transfer the temporary value of the second duty cycle as the true duty cycle to the application layer determination module.

[0012] Preferably, in the outlier determination module, the outlier determination is performed according to the monitoring result, and the corresponding processing flow is triggered specifically as follows: The outlier determination process is as follows: Start a 1s timer. When all the data collected within 1s are outliers, assign the outliers to the application layer determination module for outlier determination; When there are normal values within 1s, reset the timer and return to the data acquisition module to re-acquire data.

[0013] Preferably, the range X is 8% - 97% and 100%.

[0014] Through the basic principle determination, the present invention can automatically perform the screening method of preliminary data, reduce the burden on technicians, and avoid data errors.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) Through the high-frequency acquisition and preliminary data screening of the data acquisition module, the present invention can quickly identify and eliminate invalid or abnormal data caused by signal jitter or external interference, effectively reduce the occurrence of misjudgment situations, thereby improving the stability of the vehicle charging process. Moreover, the algorithm system provided by the present invention can be normally applied to the AC charging scenario, and can shield external interference to a certain extent without affecting the normal charging process, avoiding the scenario where users repeatedly plug and unplug the gun to maintain charging.

[0016] (2) The present invention uses the quicksort algorithm in the filtering processing module and takes the median as the true duty cycle. This method has good robustness to extreme values and noise data, can significantly improve the accuracy and reliability of the collected data, and provides a solid data basis for subsequent charging control decisions. Moreover, the algorithm system provided by the present invention has a compatible design for abnormal situations such as the output jitter of the charging pile and inaccurate acquisition at the vehicle end. In the normal charging scenario, the performance is not affected. For different abnormal situations, there are corresponding algorithms to determine. The outlier determination module monitors the data acquisition process in real time and immediately triggers the processing flow once an abnormal situation is found for timely processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] FIG. 1 is a system framework diagram of the present invention; FIG. 2 is an overall system flow chart of the present invention; Figure 3 is a flow chart of the preliminary data screening method of the present invention; Figure 4 This is the flowchart of the filtering operation of the present invention; Figure 5 This is the flowchart of the abnormal state handling of the present invention. Detailed implementation manners

[0018] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0019] Please refer to Figures 1 to 5 , which is an embodiment of the present invention. This embodiment provides an algorithm system for collecting waveforms and analyzing their behaviors based on a CP guiding circuit. This system makes a charging control decision based on real duty cycle data through real-time collection of pulse width modulation (PWM) waveform data in the CP guiding circuit and a series of data processing processes. The system includes: a data collection module, a preliminary data screening module, a filtering processing module, an outlier determination module, and an application layer determination module; Specifically in this embodiment, in the data collection module, the system uses a dedicated hardware circuit to collect pulse width modulation (PWM) waveform data from the CP guiding circuit in real time. The collection frequency is set to 1 kHz, that is, 1000 times per second, and the corresponding pulse width modulation (PWM) waveform period is 1 ms.

[0020] The data collection process is that the system continuously collects 11 groups of duty cycle data according to the set period. The calculation formula for the duty cycle D is: ; In the formula: Ton represents the duration of the high level in the pulse signal, T represents the complete period of the pulse signal, and D represents the duty cycle, which is a percentage value indicating the proportion of the time occupied by the high level within one cycle.

[0021] Specifically in this embodiment, in the preliminary data screening module, when 3 or more rising edges or falling edges are collected within one pulse period, it is determined that this group of data is invalid; When the ratio of the duration of the pulse high level to the pulse period is greater than 1 or less than 0, that is, the duty cycle exceeds the range of 0% to 100%, it is also determined that this group of data is invalid.

[0022] Then, the 11 groups of collected data are preliminarily screened to eliminate invalid data.

[0023] Specifically, in this embodiment, in the filtering processing module, the remaining data after preliminary screening is quickly sorted, and the median is taken as the temporary value of the first duty cycle; Determine whether the temporary value of the first duty cycle is within the preset range X (8% - 97% and 100%).

[0024] Then repeat the data acquisition and sorting process to obtain the temporary value of the second duty cycle, and also perform range verification.

[0025] Finally, it is determined that when the absolute value of the difference between the two temporary duty cycles is less than or equal to 2%, the temporary value of the second duty cycle is passed as the true duty cycle to the application layer decision-making module.

[0026] Specifically, in this embodiment, in the outlier determination module, a 1s timer is started to monitor the collected data, When all the collected data within 1s are outliers, that is, they do not meet the preliminary screening criteria or the filtering processing requirements, the outlier information is assigned to the application layer decision-making module for exception handling.

[0027] When there are normal values within 1s, the timer is reset, and the data acquisition module is returned to re-acquire data.

[0028] In the application layer decision-making module, according to the true duty cycle data provided by the filtering processing module, the application layer decision-making module makes a charging control decision; When receiving the exception information sent by the outlier determination module, the corresponding exception handling process is executed, such as stopping charging, issuing an alarm, etc.

[0029] The complete process is as follows: The data acquisition module continuously collects pulse width modulation (PWM) waveform data from the CP boot circuit; The preliminary data screening module preliminarily screens the collected data and eliminates invalid data; The filtering processing module quickly sorts the screened data, takes the median as the candidate value of the true duty cycle, and determines the final true duty cycle through repeated verification; The outlier determination module monitors the collected data through a timer, makes an outlier determination according to the monitoring results, and triggers the corresponding processing process; The application layer decision-making module makes a charging control decision according to the true duty cycle data, and at the same time processes the exception information sent by the outlier determination module; This embodiment combines the above-mentioned algorithm system for collecting waveforms based on the CP boot circuit and analyzing its behavior, and also proposes a method for this system, as follows: The first technical solution to achieve the purpose of this embodiment is as follows: Given that the waveform frequency is 1Khz, then a complete PWM waveform period is 1ms. The calculation formula for the duty cycle = pulse high-level duration / pulse period * 100%.

[0030] Therefore, when 3 or more rising edges or falling edges are collected within one pulse period, it is determined that the set of data is invalid; when the pulse high-level duration / pulse period is greater than 1 or less than 0, the set of data is also processed as invalid.

[0031] The second technical solution to achieve the purpose of this embodiment is: Based on the AC application scenario, perform filtering operations in the following steps: Step 1: During the AC charging process, start collecting the duty cycle. Step 2: Collect the duty cycle once every 1ms, and collect 11 groups continuously. Step 3: Perform a quicksort algorithm (from small to large) on the 11 groups of data and take the median. Step 4: Store this median as the temporary duty cycle Duty1. Step 5: Determine whether the duty cycle Duty1 meets the range X. If it holds, execute Step 10. Step 6: Repeat the actions of Step 2 and Step 3 to obtain the temporary duty cycle Duty2. Step 7: Determine whether the duty cycle Duty2 meets the range X. If it holds, execute Step 10. Step 8: Compare the duty cycle Duty1 and the duty cycle Duty2. If the absolute value of the difference is less than or equal to 2%, if the condition holds, execute Step 9; otherwise, discard this value and jump back to Step 2. Step 9: Pass the duty cycle Duty2 as the true duty cycle to the application layer for determination. Step 10: Enter the outlier determination process. Start a 1s timer. If all the collected data within 1s are outliers, assign the outliers to the application layer for outlier determination. If there is normal data within 1s, jump out and execute Step 2. The range X in Step 5 is 8% - 97% and 100%.

[0032] Through the above process, the system can accurately extract the true duty cycle from the pulse width modulation PWM waveform data and make reliable charging control decisions based on this data. The present invention can effectively screen and process the data during the AC charging process, thereby ensuring the stability and safety of the charging process.

[0033] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. An algorithm system for collecting waveforms and analyzing their behavior based on a CP-guided circuit, characterized in that: include: Data collection module, preliminary data screening module, filtering processing module, abnormal value determination module and application layer determination module; The data acquisition module includes a hardware circuit for collecting pulse width modulation (PWM) waveform data from the CP guide circuit in real time; The preliminary data screening module is used to perform preliminary screening on the collected data; The filtering processing module is used to quickly sort the filtered data and take the median as the real duty cycle; The abnormal value determination module is used to monitor the abnormal situation of the collected data through a timer, make abnormal determinations according to the monitoring results, and trigger the corresponding processing flow; The application layer determination module is used to make charging control decisions based on the real duty cycle data provided by the filtering processing module.

2. The algorithm system for collecting waveforms and analyzing behaviors based on a CP-guided circuit according to claim 1, characterized in that: In the data acquisition module, the acquisition frequency is set to 1KHz, corresponding to a pulse width modulation (PWM) waveform period of 1ms, and the duty cycle data is collected, and 11 sets of data are continuously collected according to the set period; wherein, the calculation formula of the duty cycle D is: ； Where: Ton represents the duration of the high level in the pulse signal. T represents the complete cycle of the pulse signal, and D represents the duty cycle, which is a percentage value, indicating the proportion of time occupied by the high level in one cycle.

3. The algorithm system for collecting waveforms and analyzing behaviors based on CP-guided circuit according to claim 1, characterized in that: The preliminary data screening module performs preliminary screening on the collected data, and the preliminary screening is: When three or more rising edges or falling edges are collected in one pulse cycle, the group of data is determined to be invalid; When the ratio of the pulse high level duration to the pulse period is greater than 1 or less than 0, the group of data is also determined to be invalid.

4. The algorithm system for collecting waveforms and analyzing behaviors based on a CP-guided circuit according to claim 1, characterized in that: In the filtering processing module, Firstly, the 11 sets of data collected in the data collection module are sorted by a quick sort algorithm from small to large and the median is taken, and the median is stored as the temporary value first duty cycle; Determine whether the temporary value first duty cycle meets the preset range X; Repeat the data collection and sorting process to obtain another temporary value of the second duty cycle, and determine whether it satisfies the range X; When the absolute value of the difference between the temporary value first duty cycle and the temporary value second duty cycle is less than or equal to 2%, the temporary value second duty cycle is passed to the application layer determination module as the actual duty cycle.

5. The algorithm system for collecting waveforms and analyzing their behaviors based on a CP-guided circuit according to claim 1, characterized in that: In the abnormal value determination module, abnormality determination is performed according to the monitoring results, and the corresponding processing flow is triggered. The abnormal value determination flow is as follows: Start a 1s timer. If all the data collected within 1s are abnormal values, the abnormal values ​​will be assigned to the application layer judgment module for abnormal judgment. If a normal value exists within 1 second, the timer is reset and the data acquisition module is returned to re-collect data.

6. The algorithm system for collecting waveforms and analyzing their behaviors based on a CP-guided circuit according to claim 4, characterized in that: The range X is 8% to 97% and 100%.

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