A method for testing the capacitance of a supercapacitor to be tested

Abstract

The application discloses a method for testing the capacitance of a super capacitor. The method comprises: testing the super capacitor by using each super capacitor detection circuit respectively, and obtaining the charge-discharge capacitance information of the super capacitor detected by each super capacitor detection circuit; and performing the following operation on each charge-discharge capacitance information: fitting each charge-discharge capacitance information to obtain a fitting curve; performing the following operation on each fitting curve: calculating the similarity between the fitting curve and other fitting curves to obtain the similarity values between the fitting curve and other fitting curves; and judging whether each fitting curve meets a preset condition respectively, and if yes, discarding the charge-discharge capacitance information corresponding to the fitting curve which does not meet the preset condition. The application compares the capacitances detected by each detection circuit with each other, so that more accurate capacitances are obtained through relative comparison.

Description

Technical Field

[0001] This application relates to the field of supercapacitor testing technology, and in particular to a method for testing the capacitance of a supercapacitor. Background Technology

[0002] Supercapacitors under test have been widely used in many industrial fields such as power systems, smart microgrid systems, ships, aerospace, and rail transportation, playing a vital role. However, their testing methods and standards have been controversial. Currently, China follows the national standard GB / T 34870, the enterprise standard QC / T741, and standards defined by various supercapacitor manufacturers. Internationally, there is no unified, universally accepted standard. Currently, IEC standards, USABC standards, and standards defined by some foreign capacitor manufacturers coexist, each believing its own standard best reflects scientific principles and rejecting others. Therefore, no single standard has achieved widespread consensus. Furthermore, there is no standard for judging the scientific validity of any particular standard.

[0003] Currently, most capacitance tests use only one type of test circuit, which cannot guarantee the accuracy of the test.

[0004] Therefore, it is desirable to have a technical solution to overcome or at least mitigate one of the aforementioned defects of the prior art. Summary of the Invention

[0005] The purpose of this application is to provide a method for testing the capacitance of a supercapacitor under test to overcome or at least mitigate one of the aforementioned defects in the prior art.

[0006] To achieve the above objectives, this application provides a method for testing the capacitance of a supercapacitor under test, the method comprising: Establish multiple detection circuits for supercapacitors under test; Each supercapacitor under test is tested using a separate detection circuit, and the charge and discharge capacity information of the supercapacitor under test detected by each detection circuit is obtained. For each charge / discharge capacity information, the following operation is performed: MATLAB is used to fit each charge / discharge capacity information to obtain a fitted curve; For each fitted curve, perform the following operation: calculate the similarity between the fitted curve and other fitted curves to obtain the similarity value between the fitted curve and each other fitted curve. Each fitted curve is checked to see if it meets the preset conditions. If it does, the charge / discharge capacity information corresponding to the fitted curve that does not meet the preset conditions is discarded.

[0007] Optionally, the preset condition is: If there is a fitted curve whose similarity value to all other fitted curves does not exceed a preset threshold, then it is determined that the preset condition is met.

[0008] Optionally, the capacitance testing method for the supercapacitor under test further includes: The acquired charge and discharge capacity information is preprocessed to obtain the charge and discharge capacity characteristics corresponding to each charge and discharge capacity information. Obtain the trained neural network; The various charge / discharge capacity features are fused and input into the trained neural network to obtain the remaining lifetime of the supercapacitor under test.

[0009] Optionally, during the testing process of each supercapacitor under test by the test circuit, the charging capacity or discharging capacity of the supercapacitor under test is recorded once every preset time interval.

[0010] Optionally, at least one detection circuit for the supercapacitor under test is as follows: A first charging and discharging circuit is used to connect to the supercapacitor under test. A first feedback circuit, connected to the control circuit, is used to obtain the capacitance of the supercapacitor under test when the first charge-discharge circuit tests the supercapacitor under test.

[0011] Optionally, the first charging and discharging circuit includes: A relay, which is connected to the supercapacitor under test; A diode, wherein the diode is connected in parallel with the relay; The transistor's collector is connected to both the relay and the diode. The transistor's emitter is grounded, and its base is connected to the voltage input terminal via resistor R3. The relay is also connected to resistor R2 and sampling resistor R1. The sampling resistor R1 is connected in series with a regulated power supply and control switch S. The output terminals of the control switch S, the sampling resistor R1, and the resistor R2 are all connected to the output terminals of the capacitor under test.

[0012] Optionally, at least one detection circuit for the supercapacitor under test is as follows: The second charging and discharging circuit is connected to the supercapacitor under test. A controller, connected to the second charging and discharging circuit, is used to control the second charging and discharging circuit to provide drive pulses to the main circuit; A power source, which is connected to the second charging and discharging circuit; A compensation circuit is provided, which is disposed between the power supply and the second charging and discharging circuit. One end of the compensation circuit is connected to the power supply, and the other end is connected to the second charging and discharging circuit.

[0013] Optionally, the compensation circuit includes: The grid-side charging voltage sampling unit is used to sample the real-time voltage input from the grid side when the supercapacitor under test is charged in the second charging and discharging circuit. A charging voltage comparison unit, connected to the grid-side charging voltage sampling unit, is used to compare the real-time voltage with a preset standard charging voltage when charging the supercapacitor under test, and obtain a charging voltage correction signal. The first supercapacitor under test voltage compensation unit is connected to the charging voltage comparison unit and is used to adjust the voltage across the supercapacitor under test according to the charging voltage correction signal when charging the supercapacitor under test. When the charging voltage correction signal indicates that the real-time voltage is greater than the standard charging voltage, the voltage across the supercapacitor under test is controlled to be reduced. When the charging voltage correction signal indicates that the real-time voltage is less than the standard charging voltage, the voltage across the supercapacitor under test is controlled to be increased. The supercapacitor under test charging voltage sampling unit is used to sample the real-time voltage across the supercapacitor under test when charging it. The supercapacitor under test voltage comparison unit is connected to the supercapacitor under test charging voltage sampling unit, and is used to compare the real-time voltage with the standard supercapacitor under test voltage when charging the supercapacitor under test, so as to obtain the supercapacitor under test voltage correction signal. The second supercapacitor voltage compensation unit is connected to the supercapacitor voltage comparison unit and is used to adjust the voltage across the supercapacitor under test according to the supercapacitor voltage correction signal when charging the supercapacitor under test. When the supercapacitor voltage correction signal indicates that the real-time voltage is greater than the standard supercapacitor voltage under test, the voltage across the supercapacitor under test is controlled to be reduced. When the charging voltage correction signal indicates that the real-time voltage is less than the standard supercapacitor voltage under test, the voltage across the supercapacitor under test is controlled to be increased. The standard supercapacitor voltage under test is the voltage across the supercapacitor under test when the grid side inputs a standard charging voltage.

[0014] Optionally, at least one supercapacitor detection circuit under test includes a voltage setting circuit, a charging and discharging circuit, a charging control circuit, a discharging control circuit, an MCU circuit, and a power supply circuit. The power supply circuit provides voltage to the circuit, the MCU circuit provides the logic level for the charging control circuit and the discharging control circuit to realize the charging and discharging function, and provides the PWM signal input for the voltage setting circuit. The voltage setting circuit outputs the charging and discharging setting voltage, and the charging control circuit and the discharging control circuit provide the final charging and discharging control signal for the final charging and discharging circuit. The charging and discharging circuit is connected to the supercapacitor under test.

[0015] Optionally, the step of preprocessing the acquired charge / discharge capacity information to obtain the charge / discharge capacity features corresponding to each charge / discharge capacity information includes: The charge / discharge capacity information is processed using a multi-fractional step-by-step method to obtain charge / discharge capacity characteristics.

[0016] The capacitance testing method of the supercapacitor under test in this application uses multiple capacitance detection circuits to detect the capacitance and compares the capacitance detected by each detection circuit with each other. This allows for a more accurate capacitance to be obtained through relative comparison and prevents situations where detection errors caused by using only one detection method go unnoticed. Attached Figure Description

[0017] Figure 1 This is a schematic flowchart of a method for testing the capacitance of a supercapacitor according to an embodiment of this application. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0019] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this application.

[0020] Figure 1 This is a schematic flowchart of a method for testing the capacitance of a supercapacitor according to an embodiment of this application.

[0021] like Figure 1 The capacitance testing method for the supercapacitor shown includes: Establish multiple detection circuits for supercapacitors under test; Each supercapacitor under test is tested using a separate detection circuit, and the charge and discharge capacity information of the supercapacitor under test detected by each detection circuit is obtained. For each charge / discharge capacity information, the following operation is performed: MATLAB is used to fit each charge / discharge capacity information to obtain a fitted curve; For each fitted curve, perform the following operation: calculate the similarity between the fitted curve and other fitted curves to obtain the similarity value between the fitted curve and each other fitted curve. Each fitted curve is checked to see if it meets the preset conditions. If it does, the charge / discharge capacity information corresponding to the fitted curve that does not meet the preset conditions is discarded.

[0022] The capacitance testing method of the supercapacitor under test in this application uses multiple capacitance detection circuits to detect the capacitance and compares the capacitance detected by each detection circuit with each other. This allows for a more accurate capacitance to be obtained through relative comparison and prevents situations where detection errors caused by using only one detection method go unnoticed.

[0023] In this embodiment, the preset condition is: If there is a fitted curve whose similarity value to all other fitted curves does not exceed a preset threshold, then it is determined that the preset condition is met.

[0024] In this embodiment, the capacitance testing method for the supercapacitor under test further includes: The acquired charge and discharge capacity information is preprocessed to obtain the charge and discharge capacity characteristics corresponding to each charge and discharge capacity information. Obtain the trained neural network; The various charge / discharge capacity features are fused and input into the trained neural network to obtain the remaining lifetime of the supercapacitor under test.

[0025] In this embodiment, the charge / discharge capacity information is sequence information, for example: ;in, Among them, A k This is the charge / discharge capacity sequence sampled during the k-th cycle, where k is the index number of the cycle. 1 ,ka 2 ,k and a n ,k These are the first, second, and nth sampled values ​​in the kth iteration, respectively, where 1, 2, and n are the number of samples.

[0026] In this embodiment, during the testing process of each supercapacitor under test by the test circuit, the charging capacity or discharging capacity of the supercapacitor under test is recorded once every preset time interval.

[0027] In this embodiment, a detection circuit for a supercapacitor under test is as follows: A first charging and discharging circuit is used to connect to the supercapacitor under test. A first feedback circuit, connected to the control circuit, is used to obtain the capacitance of the supercapacitor under test when the first charge-discharge circuit tests the supercapacitor under test.

[0028] In this embodiment, the first charging and discharging circuit includes: A relay, which is connected to the supercapacitor under test; A diode, wherein the diode is connected in parallel with the relay; The transistor's collector is connected to both the relay and the diode. The transistor's emitter is grounded, and its base is connected to the voltage input terminal via resistor R3. The relay is also connected to resistor R2 and sampling resistor R1. The sampling resistor R1 is connected in series with a regulated power supply and control switch S. The output terminals of the control switch S, the sampling resistor R1, and the resistor R2 are all connected to the output terminals of the capacitor under test.

[0029] In this embodiment, a detection circuit for a supercapacitor under test is as follows: The second charging and discharging circuit is connected to the supercapacitor under test. A controller, connected to the second charging and discharging circuit, is used to control the second charging and discharging circuit to provide drive pulses to the main circuit; A power source, which is connected to the second charging and discharging circuit; A compensation circuit is provided, which is disposed between the power supply and the second charging and discharging circuit. One end of the compensation circuit is connected to the power supply, and the other end is connected to the second charging and discharging circuit.

[0030] In this embodiment, the compensation circuit includes: The grid-side charging voltage sampling unit is used to sample the real-time voltage input from the grid side when the supercapacitor under test is charged in the second charging and discharging circuit. A charging voltage comparison unit, connected to the grid-side charging voltage sampling unit, is used to compare the real-time voltage with a preset standard charging voltage when charging the supercapacitor under test, and obtain a charging voltage correction signal. The first supercapacitor under test voltage compensation unit is connected to the charging voltage comparison unit and is used to adjust the voltage across the supercapacitor under test according to the charging voltage correction signal when charging the supercapacitor under test. When the charging voltage correction signal indicates that the real-time voltage is greater than the standard charging voltage, the voltage across the supercapacitor under test is controlled to be reduced. When the charging voltage correction signal indicates that the real-time voltage is less than the standard charging voltage, the voltage across the supercapacitor under test is controlled to be increased. The supercapacitor under test charging voltage sampling unit is used to sample the real-time voltage across the supercapacitor under test when charging it. The supercapacitor under test voltage comparison unit is connected to the supercapacitor under test charging voltage sampling unit, and is used to compare the real-time voltage with the standard supercapacitor under test voltage when charging the supercapacitor under test, so as to obtain the supercapacitor under test voltage correction signal. The second supercapacitor voltage compensation unit is connected to the supercapacitor voltage comparison unit and is used to adjust the voltage across the supercapacitor under test according to the supercapacitor voltage correction signal when charging the supercapacitor under test. When the supercapacitor voltage correction signal indicates that the real-time voltage is greater than the standard supercapacitor voltage under test, the voltage across the supercapacitor under test is controlled to be reduced. When the charging voltage correction signal indicates that the real-time voltage is less than the standard supercapacitor voltage under test, the voltage across the supercapacitor under test is controlled to be increased. The standard supercapacitor voltage under test is the voltage across the supercapacitor under test when the grid side inputs a standard charging voltage.

[0031] In this embodiment, a supercapacitor detection circuit includes a voltage setting circuit, a charging and discharging circuit, a charging control circuit, a discharging control circuit, an MCU circuit, and a power supply circuit. The power supply circuit provides voltage to the circuit, the MCU circuit provides the logic level for the charging control circuit and the discharging control circuit to realize the charging and discharging function, and provides the PWM signal input for the voltage setting circuit. The voltage setting circuit outputs the charging and discharging setting voltage, and the charging control circuit and the discharging control circuit provide the final charging and discharging control signal for the final charging and discharging circuit. The charging and discharging circuit is connected to the supercapacitor under test.

[0032] In this embodiment, the preprocessing of the acquired charge / discharge capacity information to obtain the charge / discharge capacity features corresponding to each charge / discharge capacity information includes: The charge / discharge capacity information is processed using a multi-fractional step-by-step method to obtain charge / discharge capacity characteristics.

[0033] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions 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 this application.

Claims

1. A method for testing the capacitance of a supercapacitor under test, characterized in that, The capacitance testing method for the supercapacitor under test includes: Acquire multiple supercapacitor detection circuits to be tested; Each supercapacitor under test is tested using a separate detection circuit, and the charge and discharge capacity information of the supercapacitor under test detected by each detection circuit is obtained. For each charge / discharge capacity information, the following operation is performed: MATLAB is used to fit each charge / discharge capacity information to obtain a fitted curve; For each fitted curve, perform the following operation: calculate the similarity between the fitted curve and other fitted curves to obtain the similarity value between the fitted curve and each other fitted curve. Determine whether each fitted curve meets the preset conditions. If it does, discard the charge and discharge capacity information corresponding to the fitted curve that meets the preset conditions. The preset conditions are: If there is a fitted curve whose similarity value to all other fitted curves does not exceed a preset threshold, then it is determined that the preset condition is met.

2. The capacitance testing method for the supercapacitor under test as described in claim 1, characterized in that, The capacitance testing method for the supercapacitor under test further includes: The acquired charge and discharge capacity information is preprocessed to obtain the charge and discharge capacity characteristics corresponding to each charge and discharge capacity information. Obtain the trained neural network; The various charge / discharge capacity features are fused and input into the trained neural network to obtain the remaining lifetime of the supercapacitor under test.

3. The capacitance testing method for the supercapacitor under test as described in claim 2, characterized in that, During the testing process of each supercapacitor under test by the test circuit, the charging capacity or discharging capacity of the supercapacitor under test is recorded once every preset time interval.

4. The capacitance testing method for the supercapacitor under test as described in claim 3, characterized in that, At least one detection circuit for the supercapacitor under test is as follows: A first charging and discharging circuit is used to connect to the supercapacitor under test. A first feedback circuit, connected to a control circuit, is used to obtain the capacitance of the supercapacitor under test when the first charging and discharging circuit tests the supercapacitor under test.

5. The capacitance testing method for the supercapacitor under test as described in claim 4, characterized in that, The first charging and discharging circuit includes: A relay, which is connected to the supercapacitor under test; A diode, wherein the diode is connected in parallel with the relay; The transistor's collector is connected to both the relay and the diode. The transistor's emitter is grounded, and its base is connected to the voltage input terminal via resistor R3. The relay is also connected to resistor R2 and sampling resistor R1. The sampling resistor R1 is connected in series with a regulated power supply and control switch S. The output terminals of the control switch S, the sampling resistor R1, and the resistor R2 are all connected to the output terminals of the capacitor under test.

6. The capacitance testing method for the supercapacitor under test as described in claim 5, characterized in that, At least one detection circuit for the supercapacitor under test is as follows: The second charging and discharging circuit is connected to the supercapacitor under test. A controller, connected to the second charging and discharging circuit, is used to control the second charging and discharging circuit to provide drive pulses to the main circuit; A power source, which is connected to the second charging and discharging circuit; A compensation circuit is provided, which is disposed between the power supply and the second charging and discharging circuit. One end of the compensation circuit is connected to the power supply, and the other end is connected to the second charging and discharging circuit.

7. The capacitance testing method for the supercapacitor under test as described in claim 6, characterized in that, The compensation circuit includes: The grid-side charging voltage sampling unit is used to sample the real-time voltage input from the grid side when the supercapacitor under test is charged in the second charging and discharging circuit. A charging voltage comparison unit, connected to the grid-side charging voltage sampling unit, is used to compare the real-time voltage with a preset standard charging voltage when charging the supercapacitor under test, and obtain a charging voltage correction signal. The first supercapacitor under test voltage compensation unit is connected to the charging voltage comparison unit and is used to adjust the voltage across the supercapacitor under test according to the charging voltage correction signal when charging the supercapacitor under test. When the charging voltage correction signal indicates that the real-time voltage is greater than the standard charging voltage, the voltage across the supercapacitor under test is controlled to be reduced. When the charging voltage correction signal indicates that the real-time voltage is less than the standard charging voltage, the voltage across the supercapacitor under test is controlled to be increased. The supercapacitor under test charging voltage sampling unit is used to sample the real-time voltage across the supercapacitor under test when charging it. The supercapacitor under test voltage comparison unit is connected to the supercapacitor under test charging voltage sampling unit, and is used to compare the real-time voltage with the standard supercapacitor under test voltage when charging the supercapacitor under test, so as to obtain the supercapacitor under test voltage correction signal. The second supercapacitor voltage compensation unit is connected to the supercapacitor voltage comparison unit and is used to adjust the voltage across the supercapacitor under test according to the supercapacitor voltage correction signal when charging the supercapacitor under test. When the supercapacitor voltage correction signal indicates that the real-time voltage is greater than the standard supercapacitor voltage under test, the voltage across the supercapacitor under test is controlled to be reduced. When the supercapacitor voltage correction signal indicates that the real-time voltage is less than the standard supercapacitor voltage under test, the voltage across the supercapacitor under test is controlled to be increased. The standard supercapacitor voltage under test is the voltage across the supercapacitor under test when the grid side inputs a standard charging voltage.

8. The capacitance testing method for the supercapacitor under test as described in claim 7, characterized in that, At least one supercapacitor under test detection circuit includes a voltage setting circuit, a charging and discharging circuit, a charging control circuit, a discharging control circuit, an MCU circuit, and a power supply circuit; The power supply circuit provides voltage to the circuit, the MCU circuit provides the logic level for the charging control circuit and the discharging control circuit to realize the charging and discharging function, and provides the PWM signal input for the voltage setting circuit. The voltage setting circuit outputs the charging and discharging setting voltage, and the charging control circuit and the discharging control circuit provide the final charging and discharging control signal for the final charging and discharging circuit. The charging and discharging circuit is connected to the supercapacitor under test.

9. The capacitance testing method for the supercapacitor under test as described in claim 8, characterized in that, The step of preprocessing the acquired charge / discharge capacity information to obtain the charge / discharge capacity features corresponding to each charge / discharge capacity information includes: The charge / discharge capacity information is processed using a multi-fractional step-by-step method to obtain charge / discharge capacity characteristics.

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