Method and device for removing electromagnetic interference in current conversion of intelligent charger

Abstract

The invention provides a method and device for removing electromagnetic interference in current conversion of an intelligent charger, and the method comprises the steps: analyzing a conversion mode of the intelligent charger according to a current change rate, and predicting the intensity of electromagnetic interference which will be generated; the scanning range is generated according to the conversion mode to obtain electromagnetic parameters of the intelligent charger, electromagnetic interference signals can be captured more accurately, and the change level of electromagnetic interference is reflected; dividing the interference mode of the intelligent charger according to the electromagnetic parameters, thereby serving as the reference of the interference intensity of the electromagnetic interference; filtering parameters are generated according to the interference mode, parameter configuration of a filter is completed according to the filtering parameters, and then electromagnetic interference generated by the intelligent charger is dynamically weakened.

Description

Technical Field

[0001] This application relates to the technical field of intelligent chargers, and particularly to a method and device for removing electromagnetic interference in current conversion of an intelligent charger. Background Art

[0002] Any electromagnetic phenomenon that may cause a decline or even failure in the performance of electronic devices, equipment, and systems, or cause damage to living or inanimate substances is called electromagnetic interference (EMI). Almost every electronic device generates electromagnetic interference signals of varying degrees during current conversion, and the resulting electromagnetic interference may affect electrical appliances sensitive to electromagnetic interference, leading to the abnormal operation of the electrical appliances.

[0003] When an intelligent charger performs current conversion, electromagnetic interference also occurs, and the intensity of this electromagnetic interference changes with the change of the conversion current of the intelligent charger. The common isolation method, filtering method, and shielding method in the prior art generally target the electromagnetic interference caused by electronic devices during constant current conversion and cannot effectively remove the electromagnetic interference generated during the use of intelligent chargers. Summary of the Invention

[0004] The purpose of this application is to provide a method and device for removing electromagnetic interference in current conversion of an intelligent charger, which can dynamically control the degree of removal of electromagnetic interference during the current conversion process and solve the problem of poor removal effect of electromagnetic interference during the current conversion of an intelligent charger.

[0005] The specific technical solutions of this application are as follows:

[0006] This application provides a method for removing electromagnetic interference in current conversion of an intelligent charger in the first aspect, including the following steps:

[0007] Calculate the current change rate of the intelligent charger, and analyze the conversion mode of the intelligent charger according to the current change rate;

[0008] Generate a scanning range according to the conversion mode, and obtain the electromagnetic parameters of the intelligent charger according to the scanning range;

[0009] Divide the interference mode of the intelligent charger according to the electromagnetic parameters;

[0010] Generate filtering parameters according to the interference mode, and remove the electromagnetic interference of the intelligent charger according to the filtering parameters.

[0011] Further, calculating the current change rate of the intelligent charger includes:

[0012] Regularly obtain the real-time output current of the intelligent charger, intercept a number of the latest real-time output currents and calculate the current difference;

[0013] Obtain the rated charging current of the smart charger;

[0014] Calculate the ratio of the current difference to the rated charging current to obtain the current change rate.

[0015] Further, analyzing the conversion mode of the smart charger according to the current change rate includes:

[0016] Select the minimum output current from several latest real-time output currents;

[0017] Analyze the conversion mode of the smart charger according to the comparison relationship between the minimum output current and the current change rate.

[0018] Further, the scanning range includes a scanning frequency. Generating the scanning range according to the conversion mode includes:

[0019] Obtain the designated electromagnetic frequency of the smart charger;

[0020] Calculate the scanning frequency according to the conversion mode and the designated electromagnetic frequency.

[0021] Further, the scanning range includes a scanning bandwidth. Generating the scanning range according to the conversion mode includes:

[0022] Obtain the designated electromagnetic bandwidth of the smart charger;

[0023] Calculate the scanning bandwidth according to the conversion mode and the designated electromagnetic bandwidth.

[0024] Further, dividing the interference mode of the smart charger according to the electromagnetic parameters includes:

[0025] Determine the electromagnetic frequency threshold according to the conversion mode;

[0026] Calculate the peak area ratio of the electromagnetic signals exceeding the electromagnetic frequency threshold in the electromagnetic parameters;

[0027] Divide the interference mode of the smart charger according to the peak area ratio.

[0028] Further, generating the filtering parameter according to the interference mode includes:

[0029] Obtain the preset filtering parameter of the smart charger;

[0030] Perform weighted calculation on the preset filtering parameter according to the interference mode to generate the filtering parameter.

[0031] Further, removing the electromagnetic interference of the smart charger according to the filtering parameter includes:

[0032] Obtain the filtering resistor and filtering capacitor of the intelligent charger;

[0033] Retrieve the dynamic filtering resistor and dynamic filtering capacitor from the filtering resistor and the filtering capacitor according to the filtering parameters;

[0034] Remove the electromagnetic interference of the intelligent charger according to the dynamic filtering resistor and the dynamic filtering capacitor.

[0035] The second aspect of this application provides an electromagnetic interference removal device in the current conversion of an intelligent charger, including:

[0036] A current detection module, configured to calculate the current change rate of the intelligent charger and analyze the conversion mode of the intelligent charger according to the current change rate;

[0037] An electromagnetic detection module, configured to generate a scanning range according to the conversion mode and obtain the electromagnetic parameters of the intelligent charger according to the scanning range;

[0038] An interference division module, configured to divide the interference mode of the intelligent charger according to the electromagnetic parameters;

[0039] An interference removal module, configured to generate filtering parameters according to the interference mode and remove the electromagnetic interference of the intelligent charger according to the filtering parameters.

[0040] Further, the current detection module is specifically configured to:

[0041] Regularly obtain the real-time output current of the intelligent charger, intercept several latest real-time output currents and calculate the current difference;

[0042] Obtain the rated charging current of the intelligent charger;

[0043] Calculate the ratio of the current difference to the rated charging current to obtain the current change rate.

[0044] Further, the current detection module is specifically configured to:

[0045] Select the minimum output current among several latest real-time output currents;

[0046] Analyze the conversion mode of the intelligent charger according to the comparison relationship between the minimum output current and the current change rate.

[0047] Further, the scanning range includes a scanning frequency, and the electromagnetic detection module is specifically configured to:

[0048] Obtain the designated electromagnetic frequency of the intelligent charger;

[0049] Calculate the scanning frequency according to the conversion mode and the designated electromagnetic frequency.

[0050] Further, the scanning range includes a scanning bandwidth, and the electromagnetic detection module is specifically configured to:

[0051] Obtain the designated electromagnetic bandwidth of the smart charger;

[0052] Calculate the scanning bandwidth according to the conversion mode and the designated electromagnetic bandwidth.

[0053] Further, the interference classification module is specifically configured to:

[0054] Determine the electromagnetic frequency threshold according to the conversion mode;

[0055] Calculate the proportion of the peak area of the electromagnetic signal exceeding the electromagnetic frequency threshold in the electromagnetic parameters;

[0056] Classify the interference mode of the smart charger according to the proportion of the peak area.

[0057] Further, the interference removal module is specifically configured to:

[0058] Obtain the preset filtering parameters of the smart charger;

[0059] Perform weighted calculation on the preset filtering parameters according to the interference mode to generate the filtering parameters.

[0060] Further, the interference removal module is specifically configured to:

[0061] Obtain the filtering resistor and filtering capacitor of the smart charger;

[0062] Retrieve the dynamic filtering resistor and dynamic filtering capacitor from the filtering resistor and the filtering capacitor according to the filtering parameters;

[0063] Remove the electromagnetic interference of the smart charger according to the dynamic filtering resistor and the dynamic filtering capacitor.

[0064] The third aspect of the present application provides a smart charger, which implements the steps in the method for removing electromagnetic interference in the current conversion of the smart charger, or includes each module in the device for removing electromagnetic interference in the current conversion of the smart charger.

[0065] In summary, the present application provides a method and device for removing electromagnetic interference in the current conversion of an intelligent charger. The conversion mode of the intelligent charger is analyzed according to the current change rate, so as to predict the intensity of electromagnetic interference that will be generated; the scanning range is generated according to the conversion mode to obtain the electromagnetic parameters of the intelligent charger, which can more accurately capture the electromagnetic interference signal and reflect the change level of electromagnetic interference; the interference mode of the intelligent charger is divided according to the electromagnetic parameters, so as to serve as the benchmark for the intensity of electromagnetic interference intervention; the filtering parameters are generated according to the interference mode, and the parameter configuration of the filter is completed according to the filtering parameters, so as to dynamically weaken the electromagnetic interference generated by the intelligent charger. Specific Embodiments

[0066] In order to make the objectives, features, and advantages of the present application more obvious and understandable, the technical solutions in the embodiments of the present application are clearly and completely described below. Obviously, the embodiments described below are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0067] The embodiment of the present application provides a method for removing electromagnetic interference in the current conversion of an intelligent charger, including the following steps:

[0068] S1: Calculate the current change rate of the intelligent charger, and analyze the conversion mode of the intelligent charger according to the current change rate;

[0069] S2: Generate a scanning range according to the conversion mode, and obtain the electromagnetic parameters of the intelligent charger according to the scanning range;

[0070] S3: Divide the interference mode of the intelligent charger according to the electromagnetic parameters;

[0071] S4: Generate filtering parameters according to the interference mode, and remove the electromagnetic interference of the intelligent charger according to the filtering parameters.

[0072] It should be noted that in S1, since the magnitude of the current does not affect the strength of electromagnetic interference, but is closely related to the magnitude of the current change rate, a current sensor built into the intelligent charger can be used to measure the real-time output current to calculate the current change rate, that is, the degree of change of the output current within a certain period of time. The degree of current conversion can be reflected by the magnitude of the current change rate, so as to predict the intensity of electromagnetic interference that will be generated.

[0073] It should be noted that in S2, a spectrum analyzer built into the smart charger can be used to detect the generated electromagnetic signals. The spectrum analyzer can be used to measure and plot the signal power within a selected frequency range. By selecting an appropriate scanning range according to the degree of current conversion, such as the scanning frequency, scanning bandwidth, etc., electromagnetic interference signals can be captured more accurately. After automatically setting the scanning range of the spectrum analyzer, the electromagnetic parameters of the smart charger, such as frequency, bandwidth, etc., can be obtained, and a visual spectrum diagram can be drawn to directly reflect the change level of electromagnetic interference.

[0074] It should be noted that in S3, the smart charger will change the current conversion intensity according to the charging and discharging process of the electrical device. Since a larger current conversion will generate stronger electromagnetic interference, a stronger interference removal ability is required to ensure the normal use of the electrical device. According to the obtained electromagnetic parameters, the intensity of electromagnetic interference generated by the smart charger can be classified, which can be used as a benchmark for the intensity of electromagnetic interference intervention.

[0075] It should be noted that in S4, a filter built into the smart charger can be used to remove electromagnetic interference. The filter is a filter circuit composed of capacitors, inductors and resistors, which can effectively filter specific frequencies or frequencies outside a specific frequency in the power line. According to the degree of electromagnetic interference, the expected filtering parameters can be calculated, and then the parameter configuration of the filter can be completed to dynamically weaken the electromagnetic interference generated by the smart charger, and automatically filter the electromagnetic interference generated by the smart charger during different degrees of current conversion.

[0076] According to the embodiments of the present application, calculating the current change rate of the smart charger includes:

[0077] Regularly obtain the real-time output current of the smart charger, intercept several latest real-time output currents and calculate the current difference;

[0078] Obtain the rated charging current of the smart charger;

[0079] Calculate the ratio of the current difference to the rated charging current to obtain the current change rate.

[0080] As an embodiment, the system obtains the real-time output current of the smart charger every once in a while (which can be set to 5 minutes) and calculates the absolute value of the difference between the two latest obtained values. At the same time, the rated charging current of the smart charger, that is, the maximum charging current, is obtained. The current change rate is calculated by the ratio of the current difference to the rated charging current, and the hardware tolerance factors of different smart chargers can be taken into account to more accurately judge the intensity of the generated electromagnetic interference.

[0081] According to the embodiments of the present application, analyzing the conversion mode of the smart charger according to the current change rate includes:

[0082] Select the minimum output current among the latest several real-time output currents;

[0083] Analyze the conversion mode of the smart charger according to the comparison relationship between the minimum output current and the current change rate.

[0084] As an embodiment, denote the current change rate as α. The system can select the minimum value among the latest two real-time output current values as the minimum output current, and calculate the ratio to the rated charging current and denote it as β. The system compares the magnitudes of β and α, and divides them into 4 current conversion modes according to the comparison results: When α is greater than 3β, it is determined as high-current conversion, denoted as flag 1; when α is within the range of β to 3β, it is determined as medium-current conversion, denoted as flag 2; when α is within the range of 0 to β, it is determined as low-current conversion, denoted as flag 3; when α = 0, it is determined that the current has not undergone current conversion, denoted as flag 0.

[0085] According to the embodiment of the present application, the scanning range includes the scanning frequency. Generating the scanning range according to the conversion mode includes:

[0086] Obtain the designated electromagnetic frequency of the smart charger;

[0087] Calculate the scanning frequency according to the conversion mode and the designated electromagnetic frequency.

[0088] As an embodiment, the designated electromagnetic frequency refers to the expected value or range of the electromagnetic interference frequency determined according to the rated power of the smart charger, etc. Intercept an appropriate range in the designated electromagnetic frequency according to the flag value corresponding to the conversion mode. By adjusting the scanning frequency range of the spectrum analyzer, specific frequencies can be observed in detail and the recognition sensitivity can be improved. For example, the designated electromagnetic frequency is 1 to kHz, the scanning frequency is 1 to (k - 1) Hz in conversion mode flag 1, and the scanning frequency is 1 to (k - 3) Hz in conversion mode flag 3.

[0089] According to the embodiment of the present application, the scanning range includes the scanning bandwidth. Generating the scanning range according to the conversion mode includes:

[0090] Obtain the designated electromagnetic bandwidth of the smart charger;

[0091] Calculate the scanning bandwidth according to the conversion mode and the designated electromagnetic bandwidth.

[0092] As an embodiment, the marked electromagnetic bandwidth refers to the expected value or range of the electromagnetic interference bandwidth determined according to the rated power of the smart charger, etc. For example, the intermediate resolution bandwidth of the spectrum analyzer is set to 3 dB. Adjusting the scanning bandwidth, i.e., the resolution bandwidth, according to the marked value corresponding to the conversion mode can achieve two purposes. One is to improve the instrument selectivity so as to distinguish two signals with very close frequencies. The other is to improve the instrument sensitivity because any circuit has thermal noise, and these noises will submerge weak signals, making the instrument unable to observe weak signals. The noise amplitude is proportional to the instrument's passband bandwidth. The wider the bandwidth, the greater the noise. Therefore, reducing the instrument's resolution bandwidth can reduce the noise of the instrument itself, thereby enhancing the ability to detect weak signals. For example, when the conversion mode is marked 1, the scanning bandwidth is 3 dB; when the conversion mode is marked 2, the scanning bandwidth is 2 dB; when the conversion mode is marked 3, the scanning bandwidth is 1 dB.

[0093] According to the embodiments of the present application, dividing the interference modes of the smart charger according to the electromagnetic parameters includes:

[0094] Determining an electromagnetic frequency threshold according to the conversion mode;

[0095] Calculating the proportion of the peak area of the electromagnetic signals exceeding the electromagnetic frequency threshold in the electromagnetic parameters;

[0096] Dividing the interference modes of the smart charger according to the proportion of the peak area.

[0097] As an embodiment, when the conversion mode is marked 1, the system determines it as a large-current conversion, and sets the electromagnetic frequency threshold of the spectrum analyzer to z, that is, the electromagnetic signals with an electromagnetic frequency greater than z generated by the current conversion are set as electromagnetic interference signals; when the conversion mode is marked 2, the system determines it as a medium-current conversion, and sets the electromagnetic frequency threshold of the spectrum analyzer to z - x, that is, the electromagnetic signals with an electromagnetic frequency exceeding z - x generated by the current conversion are set as electromagnetic interference signals; when the conversion mode is marked 3, the system determines it as a small-current conversion, and sets the electromagnetic frequency threshold of the spectrum analyzer to x, that is, the electromagnetic signals with an electromagnetic frequency exceeding x generated by the current conversion are set as electromagnetic interference signals. Then the system automatically calculates the peak area of the electromagnetic signals recognized as electromagnetic interference signals according to the spectrogram, and calculates the proportion of the peak area of the whole spectrogram. When the proportion of the peak area exceeds 50%, the system determines it as a strong interference mode and sets the weight to 3; when the proportion of the peak area is between 20% and 50%, the system determines it as a medium interference mode and sets the weight to 2; when the proportion of the peak area is less than 20%, the system determines it as a low interference mode and sets the weight to 1.

[0098] According to the embodiments of the present application, generating filtering parameters according to the interference mode includes:

[0099] Obtaining the preset filtering parameters of the smart charger;

[0100] Calculating the weighted value of the preset filtering parameters according to the interference pattern to generate the filtering parameters.

[0101] As an embodiment, the preset filtering parameters refer to the initial operating power, frequency and other parameters of the built-in filter of the smart charger after startup, and can be set to half of the maximum filtering frequency. The set value of the filtering parameters is dynamically adjusted according to the interference intensity. For example, when the interference pattern is strong interference, the system adjusts the current filtering parameters to 150% of the preset filtering parameters; when the interference pattern is medium interference, the system adjusts the current filtering parameters to 120% of the preset filtering parameters; when the interference pattern is low interference, the system adjusts the current filtering parameters to 80% of the preset filtering parameters.

[0102] According to the embodiments of the present application, removing the electromagnetic interference of the smart charger according to the filtering parameters includes:

[0103] Obtaining the filtering resistor and filtering capacitor of the smart charger;

[0104] Calling the dynamic filtering resistor and dynamic filtering capacitor from the filtering resistor and the filtering capacitor according to the filtering parameters;

[0105] Removing the electromagnetic interference of the smart charger according to the dynamic filtering resistor and the dynamic filtering capacitor.

[0106] As an embodiment, the filter is composed of a resistor R and a capacitor C. The noise input signal is connected in series through the resistor and the capacitor, and the noise output signal is taken out from the output end of the capacitor. When the frequency of the noise input signal is low, the impedance of the capacitor is large, the ability of the noise signal to pass through the capacitor is strong, and the noise output signal is large; when the frequency of the noise input signal is high, the impedance of the capacitor is small, the ability of the noise signal to pass through the capacitor is weak, and the output signal is small. The system calls the filter to access the circuit of the smart charger, obtains the currently configured filtering parameters, marked as F. At the same time, obtains the information of the optional filtering resistor R and filtering capacitor C in the standby circuit, and calculates the appropriate dynamic filtering resistor R and dynamic filtering capacitor C through the calculation formula F = 1 / (2πRC), so as to dynamically adjust the filtering frequency and adapt to the electromagnetic interference signal with size changes, so as to achieve the purpose of removing electromagnetic interference. For example, the filtering resistor R can be selected from R1(5Ω) and R2(10Ω), and the filtering capacitor C can be selected from C1(5F) and C2(10F). The system brings each filtering resistor and filtering capacitor into the calculation formula and gets that the filtering parameter Fi when R2 and C2 are connected is the closest to the currently configured filtering parameter F. The system then controls the operation of the filter by connecting the filtering resistor R2 and the filtering capacitor C2 to the circuit.

[0107] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than limiting it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for removing electromagnetic interference in current conversion of an intelligent charger, characterized in that, The steps include: Calculating the current change rate of the intelligent charger and analyzing the conversion mode of the intelligent charger according to the current change rate; Generating a scanning range according to the conversion mode and obtaining the electromagnetic parameters of the intelligent charger according to the scanning range; Dividing the interference mode of the intelligent charger according to the electromagnetic parameters; Generating filtering parameters according to the interference mode and removing the electromagnetic interference of the intelligent charger according to the filtering parameters.

2. The method for removing electromagnetic interference in the current conversion of the intelligent charger according to claim 1, wherein, Calculating the current change rate of the intelligent charger includes: Regularly obtaining the real-time output current of the intelligent charger, intercepting several latest real-time output currents and calculating the current difference; Obtaining the rated charging current of the intelligent charger; Calculating the ratio of the current difference to the rated charging current to obtain the current change rate.

3. The method for removing electromagnetic interference in the current conversion of the intelligent charger according to claim 2, characterized in that Analyzing the conversion mode of the intelligent charger according to the current change rate includes: Selecting the minimum output current among several latest real-time output currents; Analyzing the conversion mode of the intelligent charger according to the comparison relationship between the minimum output current and the current change rate.

4. The method for removing electromagnetic interference in the current conversion of the intelligent charger according to claim 1, characterized in that The scanning range includes a scanning frequency. Generating the scanning range according to the conversion mode includes: Obtaining the designated electromagnetic frequency of the intelligent charger; Calculating the scanning frequency according to the conversion mode and the designated electromagnetic frequency.

5. The method for removing electromagnetic interference in the current conversion of the intelligent charger according to claim 1, characterized in that, The scanning range includes a scanning bandwidth. Generating the scanning range according to the conversion mode includes: Obtaining the designated electromagnetic bandwidth of the intelligent charger; Calculating the scanning bandwidth according to the conversion mode and the designated electromagnetic bandwidth.

6. The method for removing electromagnetic interference in the current conversion of the intelligent charger according to claim 1, characterized in that Dividing the interference mode of the intelligent charger according to the electromagnetic parameters includes: Determining an electromagnetic frequency threshold according to the conversion mode; Calculating the peak area ratio of the electromagnetic signals exceeding the electromagnetic frequency threshold in the electromagnetic parameters; Dividing the interference mode of the intelligent charger according to the peak area ratio.

7. The method for removing electromagnetic interference in the current conversion of the intelligent charger according to claim 1, wherein, Generating filtering parameters according to the interference mode includes: Obtaining the preset filtering parameters of the intelligent charger; Performing weighted calculation on the preset filtering parameters according to the interference mode to generate the filtering parameters.

8. The method for removing electromagnetic interference in the current conversion of the intelligent charger according to claim 1, characterized in that, Removing the electromagnetic interference of the intelligent charger according to the filtering parameters includes: Obtaining the filtering resistor and filtering capacitor of the intelligent charger; Retrieving a dynamic filtering resistor and a dynamic filtering capacitor from the filtering resistor and the filtering capacitor according to the filtering parameters; Removing the electromagnetic interference of the intelligent charger according to the dynamic filtering resistor and the dynamic filtering capacitor.

9. An electromagnetic interference removal device in the current conversion of an intelligent charger, characterized in that, It includes: A current detection module for calculating the current change rate of the intelligent charger and analyzing the conversion mode of the intelligent charger according to the current change rate; An electromagnetic detection module for generating a scanning range according to the conversion mode and obtaining the electromagnetic parameters of the intelligent charger according to the scanning range; An interference division module for dividing the interference mode of the intelligent charger according to the electromagnetic parameters; An interference removal module for generating filtering parameters according to the interference mode and removing the electromagnetic interference of the intelligent charger according to the filtering parameters.

10. An intelligent charger, characterized in that, The intelligent charger implements each step in the method for removing electromagnetic interference during current conversion of the intelligent charger described in any one of claims 1 to 8, or includes each module in the device for removing electromagnetic interference during current conversion of the intelligent charger described in claim 9.