Self-calibration direct current voltage divider and test method and test device thereof

Abstract

The invention discloses a direct-current voltage divider capable of self-calibration. The direct-current voltage divider comprises a high-voltage arm and a low-voltage arm which are connected in series, the high-voltage arm comprises a first resistor and a first capacitor which are connected in parallel; in the low-voltage arm, one end of the first resistance-capacitance unit is connected with one end of the high-voltage arm, the other end is connected with the other end of the second resistance-capacitance unit, and the switch is connected in parallel with two ends of the second resistance-capacitance unit. The invention further discloses a test method and a test device of the self-calibration direct-current voltage divider, a switch is controlled to be switched on, direct-current voltage is applied to the input end of the direct-current voltage divider, and first output voltage is obtained; the control switch is turned on to obtain a second output voltage; and calculating the relative variation of the high-voltage arm first resistor so as to obtain the resistance value of the high-voltage arm first resistor. According to the technical scheme, different low-voltage arm parameters are adjusted through the on-off state of the switch, different output voltage values are obtained through two times of testing under the same input voltage, the actual high-voltage arm resistance value is obtained through calculation, and therefore detection of the high-voltage arm resistance value is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of direct current voltage measurement, and in particular relates to a self-calibrated direct current voltage divider and a testing method and a testing device thereof. Background Art

[0002] In recent years, UHV DC transmission and flexible DC transmission have developed rapidly in my country. DC voltage divider (or "DC voltage transformer") is a key equipment in DC converter station, which is used for real-time monitoring of DC operating voltage, harmonic voltage and fault step voltage of DC busbars such as ±800kV, ±400kV and ±100kV. The DC measurement accuracy during normal operation is usually 0.5%.

[0003] DC voltage dividers generally use the principle of resistor-capacitor voltage division. Both the high-voltage arm and the low-voltage arm are precision resistors and capacitors in parallel. Precision resistors are the core components of DC voltage dividers. In particular, the high-voltage arm resistors have high operating voltages and large resistance values, and are easily affected by temperature and voltage. In addition, the high-voltage arm resistors are generally composed of multiple discrete resistor elements connected in series and in parallel, and the number can reach hundreds or even thousands. When a single resistor is abnormal or the welding point has poor contact, it is not easy to be discovered. The complete autonomy and controllability of key power equipment has become a trend. At present, the manufacturing process level and some performance indicators of domestic precision resistors are still somewhat behind those of foreign countries. The long-term stability under high voltage needs to be verified, and the detection of the high-voltage arm resistance value needs to be strengthened.

[0004] The regular maintenance of the DC voltage divider in the converter station makes it difficult to accurately and directly measure the high-voltage arm resistance value of up to hundreds of MΩ, and the direct measurement method is affected by the parallel capacitance, resulting in inaccurate test results. Generally, only a relatively low DC voltage of about 100kV can be applied on site, and there is usually no standard DC voltage transformer as a reference on site, so it is impossible to obtain the accurate actual voltage value, and therefore it is impossible to reversely infer the accurate high-voltage arm resistance value through the actual transformation ratio of the voltage test. For the small changes in the high-voltage arm resistance value inside the DC voltage divider that exceed the allowable value, there is a lack of convenient and effective inspection methods, which is not conducive to equipment operation and maintenance. Summary of the invention

[0005] The purpose of the present invention is to provide a self-calibrated DC voltage divider and a test method and a test device thereof, which can adjust different low-voltage arm parameters by switching on and off, obtain different output voltage values ​​by testing twice under the same input voltage, and calculate the actual high-voltage arm resistance value, thereby realizing the detection of the high-voltage arm resistance value.

[0006] In order to achieve the above object, the solution of the present invention is:

[0007] A self-calibrating DC voltage divider comprises a high voltage arm and a low voltage arm connected in series;

[0008] The high voltage arm comprises a first resistor and a first capacitor, wherein the first resistor and the first capacitor are connected in parallel;

[0009] The low-voltage arm comprises a first resistor-capacitor unit, a second resistor-capacitor unit and a switch, one end of the first resistor-capacitor unit is connected to one end of the high-voltage arm, the other end of the first resistor-capacitor unit is connected to the other end of the second resistor-capacitor unit, and the switch is connected in parallel to the two ends of the second resistor-capacitor unit; the first resistor-capacitor unit comprises a second resistor and a second capacitor, the second resistor and the second capacitor are connected in parallel; the second resistor-capacitor unit comprises a third resistor and a third capacitor, the third resistor and the third capacitor are connected in parallel;

[0010] The input end of the DC voltage divider is the other end of the high voltage arm and the other end of the second resistor-capacitor unit in the low voltage arm, and the output end of the DC voltage divider is the two ends of the low voltage arm;

[0011] R1*C1=R2*C2=R3*C3, wherein R1, R2, and R3 are the resistance values ​​of the first resistor, the second resistor, and the third resistor respectively, and C1, C2, and C3 are the resistance values ​​of the first capacitor, the second capacitor, and the third capacitor respectively.

[0012] The resistance of the first resistor is in the hundreds of MΩ level, and a mesh resistor, a rod resistor, or a plurality of resistor elements connected in series, in parallel, or in mixed connection is used.

[0013] The resistance values ​​of the second resistor and the third resistor are in the order of hundreds or tens of kΩ.

[0014] The high-voltage arm is installed in a sealed, air-filled or oil-filled hollow insulator, and the low-voltage arm is installed in an openable low-voltage terminal box.

[0015] The method for testing the self-calibrating DC voltage divider as described above comprises:

[0016] Controlling the switch to close, applying a DC voltage to the input end of the DC voltage divider, and obtaining a first output voltage of the DC voltage divider;

[0017] The control switch is turned on, the DC voltage is maintained, and a second output voltage of the DC voltage divider is obtained;

[0018] The relative change of the first resistor of the high-voltage arm is calculated, thereby obtaining the resistance value of the first resistor of the high-voltage arm.

[0019] Particularly, obtaining the first output voltage / the second output voltage of the DC voltage divider includes, after waiting for the output voltage to be stable, collecting the output voltage of the DC voltage divider multiple times and taking an average value as the first output voltage / the second output voltage.

[0020] In particular, calculating the relative change of the first resistor of the high-voltage arm includes calculating the relative change of the first resistor of the high-voltage arm δR1 using the following formula:

[0021]

[0022] Among them, R1 is the initial resistance value of the first resistor of the high voltage arm, R2 is the resistance value of the second resistor of the low voltage arm, and R3 is the resistance value of the third resistor of the low voltage arm; U2 is the first output voltage of the DC voltage divider, and U2' is the second output voltage of the DC voltage divider.

[0023] The test device of the self-calibrating DC voltage divider as described above comprises:

[0024] A first output voltage acquisition module is configured to acquire a first output voltage of the DC voltage divider when the switch is closed and a DC voltage is applied to the input end of the DC voltage divider;

[0025] A first output voltage acquisition module is configured to acquire a second output voltage of the DC voltage divider when the switch is turned on and a DC voltage is applied to the input end of the DC voltage divider; and

[0026] The resistance change calculation module is configured to calculate the relative change of the first resistor of the high-voltage arm, so as to obtain the resistance value of the first resistor of the high-voltage arm.

[0027] The first output voltage acquisition module acquires the first output voltage of the DC voltage divider, including, after the output voltage is stabilized, collecting the output voltage of the DC voltage divider for multiple times and taking an average value as the first output voltage;

[0028] The second output voltage acquisition module acquires the second output voltage of the DC voltage divider, including, after the output voltage is stabilized, collecting the output voltage of the DC voltage divider for multiple times and taking an average value as the second output voltage.

[0029] The resistance change calculation module calculates the relative change of the first resistor of the high-voltage arm, including using the following formula to calculate the relative change of the first resistor of the high-voltage arm δR1:

[0030]

[0031] Among them, R1 is the initial resistance value of the first resistor of the high voltage arm, R2 is the resistance value of the second resistor of the low voltage arm, and R3 is the resistance value of the third resistor of the low voltage arm; U2 is the first output voltage of the DC voltage divider, and U2' is the second output voltage of the DC voltage divider.

[0032] A computer device comprises a memory, a processor, and a computer program stored in the memory and executable on the processor; when the processor executes the computer program, the steps of the above-mentioned test method are implemented.

[0033] A computer-readable storage medium stores a computer program; when the computer program is executed by a processor, the steps of the test method described above are implemented.

[0034] After adopting the above scheme, the beneficial effects of the present invention include at least: based on the DC voltage divider in the form of parallel resistor-capacitor connection, the present invention sets two series resistor-capacitor units as the low-voltage arm, which can be adjusted to different low-voltage arm parameters by the switch on and off states, and two tests under the same input voltage can obtain different output voltage values, thereby obtaining the actual high-voltage arm resistance value by calculation without a standard DC voltage transformer as a reference, and then obtaining the relative change of the high-voltage arm resistance, thereby realizing the detection of the high-voltage arm resistance value. According to the relative change of the high-voltage arm resistance, it can be judged whether the operating state of the DC voltage divider is normal, and guide the operation and maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a circuit structure schematic diagram of the DC voltage divider of the present invention;

[0036] Figure 2 It is a flow chart of the testing method of the present invention. DETAILED DESCRIPTION

[0037] The following is a more detailed description of the specific embodiments of the present invention in conjunction with the accompanying drawings and examples, so that the scheme of the present invention and its advantages in various aspects can be better understood. However, the specific embodiments and examples described below are only for the purpose of illustration, rather than for limiting the present invention.

[0038] The present invention provides a self-calibrating DC voltage divider, comprising a high voltage arm and a low voltage arm connected in series;

[0039] The high-voltage arm includes a first resistor and a first capacitor, and the first resistor and the first capacitor are connected in parallel; wherein the resistance of the first resistor is in the hundreds of MΩ level, and a mesh resistor, a rod resistor, or a plurality of resistor elements connected in series, in parallel, or in mixed connection is adopted;

[0040] The low-voltage arm includes a first resistor-capacitor unit, a second resistor-capacitor unit and a switch, one end of the first resistor-capacitor unit is connected to one end of the high-voltage arm, the other end of the first resistor-capacitor unit is connected to the other end of the second resistor-capacitor unit, and the switch is connected in parallel to the two ends of the second resistor-capacitor unit; the first resistor-capacitor unit includes a second resistor and a second capacitor, the second resistor and the second capacitor are connected in parallel; the second resistor-capacitor unit includes a third resistor and a third capacitor, the third resistor and the third capacitor are connected in parallel; wherein the resistance values ​​of the second resistor and the third resistor are in the hundreds or tens of kΩ level;

[0041] The input end of the DC voltage divider is the other end of the high voltage arm and the other end of the second resistor-capacitor unit in the low voltage arm, and the output end of the DC voltage divider is the two ends of the low voltage arm;

[0042] R1*C1=R2*C2=R3*C3, wherein R1, R2, and R3 are the resistance values ​​of the first resistor, the second resistor, and the third resistor respectively, and C1, C2, and C3 are the resistance values ​​of the first capacitor, the second capacitor, and the third capacitor respectively.

[0043] The high-voltage arm is installed in a sealed, air-filled or oil-filled hollow insulator, and the low-voltage arm is installed in an openable low-voltage terminal box.

[0044] The present invention also provides a method for testing the aforementioned self-calibrated DC voltage divider, comprising:

[0045] Controlling the switch to close, applying a DC voltage to the input end of the DC voltage divider, and obtaining a first output voltage of the DC voltage divider;

[0046] The control switch is turned on, the DC voltage is maintained, and a second output voltage of the DC voltage divider is obtained;

[0047] The relative change of the first resistor of the high-voltage arm is calculated, thereby obtaining the resistance value of the first resistor of the high-voltage arm.

[0048] The step of obtaining the first output voltage / the second output voltage of the DC voltage divider includes, after the output voltage is stabilized, collecting the output voltage of the DC voltage divider for multiple times and taking an average value as the first output voltage / the second output voltage.

[0049] The step of calculating the relative change of the first resistor of the high-voltage arm includes calculating the relative change of the first resistor of the high-voltage arm δR1 using the following formula:

[0050]

[0051] Among them, R1 is the initial resistance value of the first resistor of the high voltage arm, R2 is the resistance value of the second resistor of the low voltage arm, and R3 is the resistance value of the third resistor of the low voltage arm; U2 is the first output voltage of the DC voltage divider, and U2' is the second output voltage of the DC voltage divider.

[0052] The present invention also provides a testing device for the aforementioned self-calibrating DC voltage divider, comprising:

[0053] A first output voltage acquisition module is configured to acquire a first output voltage of the DC voltage divider when the switch is closed and a DC voltage is applied to the input end of the DC voltage divider;

[0054] A first output voltage acquisition module is configured to acquire a second output voltage of the DC voltage divider when the switch is turned on and a DC voltage is applied to the input end of the DC voltage divider; and

[0055] The resistance change calculation module is configured to calculate the relative change of the first resistor of the high-voltage arm, so as to obtain the resistance value of the first resistor of the high-voltage arm.

[0056] The first output voltage acquisition module acquires the first output voltage of the DC voltage divider, including, after the output voltage is stabilized, collecting the output voltage of the DC voltage divider for multiple times and taking the average value as the first output voltage;

[0057] The second output voltage acquisition module acquires the second output voltage of the DC voltage divider, including, after the output voltage is stabilized, collecting the output voltage of the DC voltage divider for multiple times and taking an average value as the second output voltage.

[0058] The resistance change calculation module calculates the relative change of the first resistance of the high-voltage arm, including using the following formula to calculate the relative change of the first resistance of the high-voltage arm δR1:

[0059]

[0060] Among them, R1 is the initial resistance value of the first resistor of the high voltage arm, R2 is the resistance value of the second resistor of the low voltage arm, and R3 is the resistance value of the third resistor of the low voltage arm; U2 is the first output voltage of the DC voltage divider, and U2' is the second output voltage of the DC voltage divider.

[0061] like Figure 1 As shown, an embodiment of the present invention provides a self-calibrating DC voltage divider, including a high-voltage arm and a low-voltage arm connected in series, the high-voltage arm and the low-voltage arm are both parallel connections of resistors and capacitors, wherein the high-voltage arm and the low-voltage arm are both parallel connections of resistors and capacitors, the high-voltage arm is formed by a resistor R1 and a capacitor C1 in parallel, and the low-voltage arm is composed of two parts of resistor-capacitor units connected in series, including a resistor R2, a capacitor C2, a resistor R3, and a capacitor C3, wherein R2 and R3 are respectively connected in parallel with C2 and C3 and then connected in series, a switch S1 is connected in parallel at both ends of R3 and C3, the relationship between the resistor and the capacitor is R1*C1=R2*C2=R3*C3, the input voltage is applied to both ends of the voltage divider, and the voltage is output from both ends of the low-voltage arm.

[0062] The high-voltage arm resistor R1 has a resistance of hundreds of MΩ and operates at a high voltage. It is composed of a plurality of resistor elements connected in series and in parallel, or a mesh resistor or a rod resistor with a certain length.

[0063] The low-voltage arm resistors, including R2 and R3, have a resistance of hundreds or tens of kΩ, work at low voltage, and use high-stability, low-temperature drift precision resistors;

[0064] In normal operation, the switch S1 is closed, and R3 and C3 do not participate in voltage division;

[0065] In the self-calibration state, the switch S1 is opened, and R3 and C3 participate in voltage division.

[0066] Preferably, depending on the operating voltage and installation space, the high-voltage arm is installed in a sealed, gas-filled or oil-filled hollow insulator, and the low-voltage arm is installed in an openable low-voltage terminal box, so that the switch S1 in the low-voltage arm can be easily operated.

[0067] Table 1 below shows a design parameter of a ±800kV DC voltage divider in an embodiment of the present invention, wherein the operating voltage of R2 and R3 is less than 100V, and they work at low voltage. Highly stable and low temperature drift precision resistors are used, and their resistance values ​​can also be conveniently measured. Under normal operation, it can be considered that the resistance values ​​of R2 and R3 will not change. The purpose of capacitors C1, C2, and C3 is to equalize the voltage under alternating voltage and improve the frequency characteristics. The loss value is very low. After being stable under DC voltage, it can be considered that they have no effect on the voltage divider value.

[0068] Table 1

[0069] Rated primary DC voltage 800kV <![CDATA[R1]]> 800MΩ <![CDATA[R2]]> 50kΩ <![CDATA[R3]]> 50kΩ <![CDATA[C1]]> 250pF <![CDATA[C2]]> 4μF <![CDATA[C3]]> 4μF

[0070] like Figure 2 As shown, an embodiment of the present invention provides a self-calibration test method for a DC voltage divider, based on the DC voltage divider provided in the above embodiment, comprising the following steps:

[0071] Step 1, when the DC voltage divider is in normal operation, a certain DC voltage is applied from the input end of the DC voltage divider. After the voltage stabilizes, a precision meter is used to test and record the output voltage of the DC voltage divider. Multiple measurements are taken and the average value is obtained to obtain U2. The stabilization time of the output voltage value under DC voltage is related to the resistance and capacitance parameters. Generally, it can be stabilized within a few seconds. For convenience, a longer time can be uniformly determined. For example, the data is recorded after the voltage is applied for 1 minute. The accuracy can be improved by taking multiple measurements and taking the average value. In addition, precision meters use precision meters with higher resolution and accuracy, such as Keithley 2001 digital multimeter, which has a 7.5-bit resolution and a basic accuracy of 0.0018%.

[0072] Step 2, keep applying voltage, open switch S1, enter the self-calibration state, and after the voltage stabilizes, use a precision meter to test and record the output voltage of the DC voltage divider, measure multiple times and take the average value to obtain U2'.

[0073] Step 3, when the initial value of R1 and R2 and R3 are known, the relative change of the high-voltage arm resistance R1 is calculated by the following formula:

[0074]

[0075] Step 4, complete the test, close the switch S1, and restore the DC voltage divider to normal operation.

[0076] Take the DC voltage divider in Table 1 as an example. It is known that the initial value of R1 is 800MΩ, and R2 and R3 are both 50kΩ. If the applied DC voltage is about 100kV, the actual voltage has a certain deviation, but the accurate voltage value cannot be directly measured and obtained. Here it is still calculated based on 100kV. At this time, the rated output voltage of the DC voltage divider should be 6.2496V. If R1 has a deviation of 0.5%, that is, it becomes 804MΩ, if a 7.5-bit resolution meter is used for testing, the DC voltage divider output voltage actually measured in step 1 is:

[0077]

[0078] The actual measured voltage at the output of the DC voltage divider in step 2 is

[0079]

[0080] The relative change of the high-voltage arm resistance R1 calculated by step 3 is:

[0081] δR1=0.42%

[0082] The test results are basically consistent with the actual 0.5% deviation, indicating that the test method is feasible. If a meter with higher resolution, such as an 8.5-bit resolution meter, is used, a more accurate result can be obtained.

[0083] An embodiment of the present invention also provides another computer device, including a processor and a memory configured to store a computer program that can be run on the processor; wherein, when the processor is configured to run the computer program, the method steps in the aforementioned embodiment are executed.

[0084] In practical applications, the processor includes a field programmable gate array (FPGA), a central processing unit (CPU) or a digital signal processor (DSP). It is understandable that for different devices, the electronic device used to implement the function of the processor can also be other, and the embodiment of the present invention does not specifically limit it.

[0085] The above-mentioned memory can be a volatile memory (volatile memory), such as a random access memory (RAM); or a non-volatile memory (non-volatile memory), such as a read-only memory (ROM), a flash memory, a hard disk (HDD) or a solid-state drive (SSD); or a combination of the above-mentioned types of memory, and provide instructions and data to the processor.

[0086] In an exemplary embodiment, an embodiment of the present invention further provides a computer-readable storage medium for storing a computer program.

[0087] Optionally, the computer-readable storage medium can be applied to any one of the methods in the embodiments of the present invention, and the computer program enables the computer to execute the corresponding processes implemented by the processor in each method in the embodiments of the present invention. For the sake of brevity, they are not described here.

[0088] In the several embodiments provided by the present invention, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0089] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes. The schemes in the embodiments of the present invention may be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0090] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0091] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0092] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0093] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0094] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A self-calibrating DC voltage divider, characterized in that: It includes a high-voltage arm and a low-voltage arm connected in series; The high voltage arm comprises a first resistor and a first capacitor, wherein the first resistor and the first capacitor are connected in parallel; The low-voltage arm comprises a first resistor-capacitor unit, a second resistor-capacitor unit and a switch, one end of the first resistor-capacitor unit is connected to one end of the high-voltage arm, the other end of the first resistor-capacitor unit is connected to the other end of the second resistor-capacitor unit, and the switch is connected in parallel to the two ends of the second resistor-capacitor unit; the first resistor-capacitor unit comprises a second resistor and a second capacitor, the second resistor and the second capacitor are connected in parallel; the second resistor-capacitor unit comprises a third resistor and a third capacitor, the third resistor and the third capacitor are connected in parallel; The input end of the DC voltage divider is the other end of the high voltage arm and the other end of the second resistor-capacitor unit in the low voltage arm, and the output end of the DC voltage divider is the two ends of the low voltage arm; R1*C1=R2*C2=R3*C3, wherein R1, R2, and R3 are the resistance values ​​of the first resistor, the second resistor, and the third resistor respectively, and C1, C2, and C3 are the resistance values ​​of the first capacitor, the second capacitor, and the third capacitor respectively.

2. The self-calibrating DC voltage divider according to claim 1, characterized in that: The resistance of the first resistor is in the hundreds of MΩ level, and a mesh resistor, a rod resistor, or a plurality of resistor elements connected in series, in parallel, or in mixed connection is used.

3. The self-calibrating DC voltage divider according to claim 1, wherein: The resistance values ​​of the second resistor and the third resistor are in the order of hundreds or tens of kΩ.

4. The self-calibrating DC voltage divider according to claim 1, wherein: The high-voltage arm is installed in a sealed, air-filled or oil-filled hollow insulator, and the low-voltage arm is installed in an openable low-voltage terminal box.

5. The method for testing a self-calibrated DC voltage divider according to claim 1, wherein: Controlling the switch to close, applying a DC voltage to the input end of the DC voltage divider, and obtaining a first output voltage of the DC voltage divider; The control switch is turned on, the DC voltage is maintained, and a second output voltage of the DC voltage divider is obtained; The relative change of the first resistor of the high-voltage arm is calculated, thereby obtaining the resistance value of the first resistor of the high-voltage arm.

6. The testing method according to claim 5, characterized in that: Obtaining the first output voltage / second output voltage of the DC voltage divider includes, after the output voltage is stabilized, collecting the output voltage of the DC voltage divider multiple times and taking an average value as the first output voltage / second output voltage.

7. The testing method according to claim 5, characterized in that: Calculating the relative change of the first resistor of the high-voltage arm includes calculating the relative change of the first resistor of the high-voltage arm δR1 using the following formula: Among them, R1 is the initial resistance value of the first resistor of the high voltage arm, R2 is the resistance value of the second resistor of the low voltage arm, and R3 is the resistance value of the third resistor of the low voltage arm; U2 is the first output voltage of the DC voltage divider, and U2' is the second output voltage of the DC voltage divider.

8. The self-calibrating DC voltage divider testing device according to claim 1, characterized in that: include, A first output voltage acquisition module is configured to acquire a first output voltage of the DC voltage divider when the switch is closed and a DC voltage is applied to the input end of the DC voltage divider; A first output voltage acquisition module is configured to acquire a second output voltage of the DC voltage divider when the switch is turned on and a DC voltage is applied to the input end of the DC voltage divider; as well as, The resistance change calculation module is configured to calculate the relative change of the first resistor of the high-voltage arm, so as to obtain the resistance value of the first resistor of the high-voltage arm.

9. The testing device according to claim 8, characterized in that: The first output voltage acquisition module acquires the first output voltage of the DC voltage divider, including, after the output voltage is stabilized, collecting the output voltage of the DC voltage divider for multiple times and taking an average value as the first output voltage; The second output voltage acquisition module acquires the second output voltage of the DC voltage divider, including, after the output voltage is stabilized, collecting the output voltage of the DC voltage divider for multiple times and taking an average value as the second output voltage.

10. The testing device according to claim 8, characterized in that: The resistance change calculation module calculates the relative change of the first resistance of the high-voltage arm, including calculating the relative change of the first resistance of the high-voltage arm δR1 using the following formula: Among them, R1 is the initial resistance value of the first resistor of the high voltage arm, R2 is the resistance value of the second resistor of the low voltage arm, and R3 is the resistance value of the third resistor of the low voltage arm; U2 is the first output voltage of the DC voltage divider, and U2' is the second output voltage of the DC voltage divider.

11. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor; characterized in that: When the processor executes the computer program, the steps of the testing method according to any one of claims 5 to 7 are implemented.

12. A computer-readable storage medium storing a computer program; characterized in that: When the computer program is executed by a processor, the steps of the testing method according to any one of claims 5 to 7 are implemented.

Images