Accuracy evaluation device and method for Rogowski coil calibrator

Abstract

The invention discloses an accuracy evaluation device and method for a Rogowski coil calibrator, and relates to the field of Rogowski coils. According to the method, a standard current transformer is electrically connected with the output end of a primary current generator and is used for generating alternating magnetic flux through detected current and inducing secondary current based on the alternating magnetic flux; the input end of the coaxial shunt is connected with the output of the standard current transformer, the output end of the coaxial shunt is connected with the Rogowski coil calibrator, and the coaxial shunt is used for converting the secondary current into a voltage signal and inputting the voltage signal into the Rogowski coil calibrator; and the Rogowski coil calibrator is connected with the output of the standard current transformer and is used for analyzing the secondary current output by the standard current transformer and the voltage signal input by the coaxial shunt, that is, the calibration can be realized through one standard current transformer, the use of two standard current sources is avoided, and the equipment cost and the operation complexity are reduced.

Description

Technical Field

[0001] The invention relates to the field of Rogowski coils, and in particular to an accuracy evaluation device and method for a Rogowski coil tester. Background Art

[0002] In the prior art, the commonly used Figure 2 The calibration structure of the dual standard power supply shown in the figure uses two standard current sources L1 and L2 working online as the standard for calibration. The specific connection method is:

[0003] The current output terminal S of the standard current source L1 01 , S X1 Connect to the standard sampling unit terminals S1 and S2 of the calibrator. The current output terminal S of the standard current source L2 02 , S X2 Connect to the terminals K1 and K2 of the sampling unit under test of the calibrator through the current-voltage converter, that is, input voltage signals to the terminals K1 and K2 of the sampling unit under test through the current-voltage converter. And ground as required.

[0004] Adjust the standard current source to output current signals I1 and I2 of corresponding amplitude and phase (L1 outputs I1, L2 outputs I2). Keep I1 and I2 consistent with the product specifications. Observe and record the indications of the calibrator. Analyze and evaluate the accuracy of the Rogowski coil calibrator based on the indications of the calibrator.

[0005] The main problems with this verification method include:

[0006] High cost: Using two online standard current sources as the standard for calibration, the equipment cost is relatively high. Complex operation: The output of the two standard current sources needs to be precisely adjusted, which is relatively complex. Long time period: The entire calibration process takes a long time, affecting work efficiency. Dependence on external equipment: The need to rely on external standard current sources increases the difficulty of equipment management and maintenance. Summary of the invention

[0007] In order to solve the above technical problems and improve the output accuracy of the Rogowski coil tester during verification, the present invention proposes an accuracy evaluation device for the Rogowski coil tester, comprising:

[0008] A primary current generator, used to generate the current to be measured;

[0009] a standard current transformer, electrically connected to the output terminal of the primary current generator, for generating an alternating magnetic flux through the current to be measured, and inducing a secondary current based on the alternating magnetic flux;

[0010] A coaxial shunt, whose input end is connected to the output of the standard current transformer and whose output end is connected to the Rogowski coil calibrator, is used to convert the secondary current into a voltage signal and input it into the Rogowski coil calibrator;

[0011] The Rogowski coil tester is connected to the output of the standard current transformer and is used to analyze the secondary current output by the standard current transformer and the voltage signal input by the coaxial shunt.

[0012] Furthermore, the standard current transformer comprises: a primary side and a secondary side; wherein:

[0013] The primary side is electrically connected to the output end of the primary current generator; the primary side is used to generate an alternating magnetic flux through the current to be measured; and the secondary side generates a secondary current through electromagnetic induction under the action of the alternating magnetic flux.

[0014] Further, the primary side includes: a primary coil;

[0015] The output end of the primary current generator outputs the measured current to the primary coil; the primary coil generates an alternating magnetic flux through the measured current.

[0016] Furthermore, the input end and the output end of the coaxial shunt both include a positive terminal and a negative terminal.

[0017] Further, the secondary side includes: a secondary coil, and a positive connection terminal S1 arranged at the positive end of the secondary coil and a negative connection terminal S2 arranged at the negative end of the secondary coil;

[0018] The secondary coil is connected to the positive pole of the Rogowski coil tester through the positive pole connection terminal S1 and is connected to the negative pole of the coaxial shunt input end through the negative pole connection terminal S2; the negative pole of the Rogowski coil tester is connected to the positive pole of the coaxial shunt input end;

[0019] The secondary coil induces a secondary current based on the alternating magnetic flux generated by the primary coil and inputs the secondary current into the coaxial shunt and the Rogowski coil tester.

[0020] Furthermore, the Rogowski coil tester comprises:

[0021] A standard signal input terminal, which is used to connect the secondary current induced by the secondary coil and input it into the coaxial shunt; the positive pole K1 of the standard signal input terminal is connected to the positive connection terminal S1, and the negative pole K2 is connected to the positive pole of the coaxial shunt input terminal; the negative pole of the coaxial shunt input terminal is connected to the negative connection terminal S2;

[0022] The measured signal input terminal is used to access the voltage signal output by the coaxial shunt; the positive pole V1 of the measured signal input terminal is connected to the positive terminal of the coaxial shunt output terminal, and the negative pole V2 is connected to the negative terminal of the coaxial shunt output terminal.

[0023] Furthermore, the accuracy assessment device further comprises:

[0024] The evaluator connected to the output terminal of the Rogowski coil calibrator is used to receive the analysis result of the Rogowski coil calibrator and evaluate the accuracy of the Rogowski coil calibrator according to the analysis result.

[0025] Furthermore, the primary current generator comprises:

[0026] A voltage regulator and a current booster; the input end of the voltage regulator is connected to a power supply, and the output end is connected to the input end of the current booster; the voltage regulator is used to adjust the voltage input to the current booster; the output end of the current booster is used to output the measured current to the primary coil; the measured current output by the current booster increases with the increase of the output voltage of the voltage regulator.

[0027] The embodiment of the present invention further proposes a method for evaluating the accuracy of a Rogowski coil tester, comprising:

[0028] Construct an accuracy evaluation device, and form a current loop through the accuracy evaluation device; the accuracy evaluation device includes: a primary current generator; a standard current transformer, which is electrically connected to the output end of the primary current generator; a coaxial shunt, whose input end is connected to the output of the standard current transformer, and whose output end is connected to a Rogowski coil tester; an evaluator connected to the output end of the Rogowski coil tester; the Rogowski coil tester is connected to the output of the standard current transformer;

[0029] Generate the measured current through a primary current generator;

[0030] The measured current generated by the primary current generator is used to generate an alternating magnetic flux through a standard current transformer, and a secondary current is induced based on the alternating magnetic flux;

[0031] The secondary current output by the standard current transformer is connected through a coaxial shunt and converted into a voltage signal before being input into the Rogowski coil tester;

[0032] The ratio difference and phase difference between the secondary current output by the standard current transformer and the voltage signal input by the coaxial shunt are calculated by using the Rogowski coil tester;

[0033] The accuracy of the Rogowski coil tester is evaluated by an evaluator using ratio difference and phase difference.

[0034] Furthermore, the evaluator uses the ratio difference and the phase difference to evaluate the accuracy of the Rogowski coil tester, specifically: judging whether the ratio difference does not exceed a first preset value and whether the phase difference does not exceed a second preset value. If both conditions are met, it indicates that the accuracy of the Rogowski coil tester is good.

[0035] Compared with the prior art, the present invention has at least the following beneficial effects:

[0036] (1) In the present invention, the standard current transformer is electrically connected to the output end of the primary current generator, and is used to generate an alternating magnetic flux through the measured current, and to induce a secondary current based on the alternating magnetic flux; the coaxial shunt has an input end connected to the output of the standard current transformer, and an output end connected to a Rogowski coil calibrator, and is used to convert the secondary current into a voltage signal and input it into the Rogowski coil calibrator; the Rogowski coil calibrator is connected to the output of the standard current transformer, and is used to analyze the secondary current output by the standard current transformer and the voltage signal input by the coaxial shunt. That is, the present invention can realize calibration through a single standard current transformer, avoiding the use of two standard current sources, and reducing equipment cost and operation complexity;

[0037] (2) The coaxial shunt can directly convert the secondary current signal of the standard current transformer into a voltage signal, which simplifies the calibration process. At the same time, since the coaxial shunt is equivalent to a pure resistor, the current signal will not produce an angle difference after being transformed by the coaxial shunt, thereby improving the output accuracy of the Rogowski coil calibrator;

[0038] (3) By simultaneously inputting the secondary current signal of the standard current transformer into the standard signal input terminal of the calibrator and the coaxial shunt, the integrity and accuracy of the signal are ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 The present invention is a structural diagram of an accuracy evaluation device for a Rogowski coil calibrator;

[0040] Figure 2 This is a verification structure diagram of a dual-standard power supply used in the prior art;

[0041] Figure 3 The present invention is a flow chart of an accuracy evaluation method for a Rogowski coil calibrator;

[0042] Figure 4 A detailed structural diagram of an accuracy assessment device for a Rogowski coil calibrator.

[0043] In the figure:

[0044] 11. Voltage regulator; 12. Current booster; 2. Standard current transformer; 21. Primary coil; 22. Secondary coil; 23. Iron core; 3. Rogowski coil calibrator; 4. Coaxial shunt. DETAILED DESCRIPTION

[0045] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0046] Embodiment 1

[0047] In order to solve the above technical problems and improve the output accuracy of the Rogowski coil calibrator during calibration, Figure 1 or Figure 4 As shown, the present invention proposes an accuracy evaluation device for a Rogowski coil tester, comprising:

[0048] A primary current generator, used to generate the current to be measured;

[0049] The primary current generator comprises:

[0050] A voltage regulator 11 and a current booster 12; the input end of the voltage regulator 11 is connected to a power supply, and the output end is connected to the input end of the current booster 12; the voltage regulator 11 is used to adjust the voltage input to the current booster 12; the output end of the current booster 12 is used to output the measured current to the primary coil 21; the measured current output by the current booster 12 increases with the increase of the output voltage of the voltage regulator.

[0051] A standard current transformer 2, electrically connected to the output terminal of the primary current generator, for generating an alternating magnetic flux through the current to be measured, and inducing a secondary current based on the alternating magnetic flux;

[0052] In this embodiment, the accuracy level of the standard current transformer 2 is 0.01S.

[0053] The standard current transformer 2 comprises: a primary side and a secondary side, and an iron core 23 arranged between the primary side and the secondary side; wherein:

[0054] The primary side is electrically connected to the output end of the primary current generator; the primary side is used to generate an alternating magnetic flux through the current to be measured; and the secondary side generates a secondary current through electromagnetic induction under the action of the alternating magnetic flux.

[0055] The primary side includes: a primary coil 21;

[0056] The output end of the primary current generator outputs the measured current to the primary coil 21; the primary coil 21 generates an alternating magnetic flux through the measured current.

[0057] The input end and the output end of the coaxial shunt 4 both include a positive terminal and a negative terminal.

[0058] The secondary side includes: a secondary coil 22, and a positive connection terminal S1 provided at the positive end of the secondary coil 22 and a negative connection terminal S2 provided at the negative end of the secondary coil 22;

[0059] A coaxial shunt 4, whose input end is connected to the output of the standard current transformer 2, and whose output end is connected to the Rogowski coil tester 3, is used to convert the secondary current into a voltage signal and input it into the Rogowski coil tester 3;

[0060] In this embodiment, the accuracy grade of the coaxial splitter 4 is 0.005.

[0061] The Rogowski coil tester 3 is connected to the output of the standard current transformer 2 and is used to analyze the secondary current output by the standard current transformer 2 and the voltage signal input by the coaxial shunt 4 .

[0062] The secondary coil 22 is connected to the positive electrode of the Rogowski coil tester 3 through the positive electrode connection terminal S1 and is connected to the negative electrode of the input end of the coaxial shunt 4 through the negative electrode connection terminal S2; the negative electrode of the Rogowski coil tester is connected to the positive electrode of the input end of the coaxial shunt;

[0063] The secondary coil 22 induces a secondary current based on the alternating magnetic flux generated by the primary coil 21 and inputs the secondary current into the coaxial shunt 4 and the Rogowski coil tester 3 .

[0064] The Rogowski coil tester 3 comprises:

[0065] A standard signal input terminal, which is used to receive the secondary current induced by the secondary coil 22 and input the coaxial shunt 4; the positive electrode K1 of the standard signal input terminal is connected to the positive electrode connection terminal S1, and the negative electrode K2 is connected to the positive electrode of the input terminal of the coaxial shunt 4; the negative electrode of the input terminal of the coaxial shunt 4 is connected to the negative electrode connection terminal S2;

[0066] That is to say, a current loop is formed between the standard current transformer 2, the Rogowski coil tester 3 and the coaxial shunt 4: positive electrode connection terminal S1> positive electrode K1 of the standard signal input terminal> negative electrode K2 of the standard signal input terminal> positive electrode + of the input terminal of the coaxial shunt 4> negative electrode of the input terminal of the coaxial shunt 4-> negative electrode connection terminal S2. Through this current loop, the Rogowski coil tester 3 and the coaxial shunt 4 can both be connected to the secondary current induced by the secondary coil 22.

[0067] The measured signal input terminal is used to access the voltage signal output by the coaxial shunt 4; the positive pole V1 of the measured signal input terminal is connected to the positive terminal + of the output terminal of the coaxial shunt 4, and the negative pole V2 is connected to the negative terminal - of the output terminal of the coaxial shunt 4.

[0068] In the prior art, the Rogowski coil calibrator is used to calibrate the standard signal ( Figure 2I1 in) and the measured signal ( Figure 2 In this embodiment, the secondary current collected by the standard current transformer 2 is sent to the standard signal input terminal of the Rogowski coil tester 3. The secondary current signal passes through the coaxial shunt 4 at the same time and is converted into a voltage signal, which is sent to the measured signal input terminal of the Rogowski coil tester 3. The Rogowski coil tester 3 calculates the ratio difference and phase difference through the secondary current output by the standard current transformer 2 and the voltage signal input by the coaxial shunt 4.

[0069] It should be explained that the coaxial shunt 4 is essentially a precision resistor element. When current flows through it, a corresponding voltage drop will be generated, and this voltage drop is proportional to the current flowing through it. Because it is purely resistive, it will not introduce any phase delay or distortion in theory, which means that after the current signal passes through the coaxial shunt 4, its phase remains unchanged. In the calibration process of the Rogowski coil tester 3, this embodiment uses this point to eliminate the influence of phase error. Specifically, when the coaxial shunt 4 is used to replace the traditional current-voltage converter, it is actually replacing the component with unknown characteristics with a component with a known characteristic (coaxial shunt 4). Since the phase error of the coaxial shunt 4 is extremely small and almost negligible, it can be assumed that it has no effect on the phase. Therefore, when the output voltage of the coaxial shunt 4 is compared with the secondary current of the standard current transformer 2, any observed phase difference can be attributed to the error of the Rogowski coil tester 3 itself. In other words, if it is found that the Rogowski coil tester 3 shows a certain phase difference or ratio difference, it can be concluded that this is a deviation of the instrument itself, rather than the true attribute of the object to be measured.

[0070] The advantage of this calibration structure is that it greatly simplifies the calibration process while also providing higher accuracy and stability. In this way, not only can the performance of the Rogowski coil tester 3 be quickly and effectively evaluated, but also its reliability and consistency during the calibration process can be ensured.

[0071] The accuracy assessment device also includes:

[0072] The evaluator connected to the output terminal of the Rogowski coil tester 3 is used to receive the analysis result of the Rogowski coil tester 3 and evaluate the accuracy of the Rogowski coil tester 3 according to the analysis result.

[0073] It should be noted that if either the ratio difference or the phase difference exceeds a preset allowable error range, the evaluator will consider the accuracy of the Rogowski coil tester to be insufficient. The preset allowable error range is usually set according to industry standards or specific application requirements.

[0074] In the present invention, the standard current transformer is electrically connected to the output end of the primary current generator, and is used to generate an alternating magnetic flux through the measured current, and to induce a secondary current based on the alternating magnetic flux; the coaxial shunt has an input end connected to the output of the standard current transformer, and an output end connected to a Rogowski coil calibrator, and is used to convert the secondary current into a voltage signal and input it into the Rogowski coil calibrator; the Rogowski coil calibrator is connected to the output of the standard current transformer, and is used to analyze the secondary current output by the standard current transformer and the voltage signal input by the coaxial shunt, that is, the present invention can realize calibration through one standard current transformer, avoids the use of two standard current sources, and reduces equipment cost and operation complexity.

[0075] Embodiment 2

[0076] In order to solve the above technical problems and improve the output accuracy of the Rogowski coil calibrator during calibration, Figure 3 As shown, the embodiment of the present invention also proposes an accuracy evaluation method for a Rogowski coil tester, comprising:

[0077] Construct an accuracy evaluation device, and form a current loop through the accuracy evaluation device; the accuracy evaluation device includes: a primary current generator; a standard current transformer, which is electrically connected to the output end of the primary current generator; a coaxial shunt, whose input end is connected to the output of the standard current transformer, and whose output end is connected to a Rogowski coil tester; an evaluator connected to the output end of the Rogowski coil tester; the Rogowski coil tester is connected to the output of the standard current transformer;

[0078] Generate the measured current through a primary current generator;

[0079] The measured current generated by the primary current generator is used to generate an alternating magnetic flux through a standard current transformer, and a secondary current is induced based on the alternating magnetic flux;

[0080] The secondary current output by the standard current transformer is connected through a coaxial shunt and converted into a voltage signal before being input into the Rogowski coil tester;

[0081] The ratio difference and phase difference between the secondary current output by the standard current transformer and the voltage signal input by the coaxial shunt are calculated by using the Rogowski coil tester;

[0082] The accuracy of the Rogowski coil tester is evaluated by an evaluator using ratio difference and phase difference.

[0083] Specifically:

[0084] The secondary current output by the standard current transformer is a standard signal, whose amplitude and phase are known; this signal is used as a reference standard for comparison with the measured signal;

[0085] The voltage signal input by the coaxial shunt is the measured signal for measurement and analysis.

[0086] 1. Calculation of ratio difference. Ratio difference refers to the amplitude difference between the measured signal and the standard signal. The calculation formula is as follows:

[0087]

[0088] in:

[0089] IStandard is the secondary current (standard signal) output by the standard current transformer;

[0090] I is the current (measured signal) obtained by inverting the voltage signal converted by the coaxial shunt.

[0091] Assuming the resistance of the coaxial shunt is R, the measured current I 被测 The voltage signal V can be converted by the coaxial shunt 被测 The calculation results are:

[0092]

[0093] Therefore, the formula for calculating the ratio difference becomes:

[0094]

[0095] 2. Calculation of phase difference: Phase difference refers to the phase difference between the measured signal and the standard signal. The calculation formula is as follows:

[0096] Phase difference = θ 标准 -θ 被测 ;

[0097] in:

[0098] θ 标准 is the phase of the secondary current output by the standard current transformer;

[0099] θ 被测 is the phase of the voltage signal after conversion by the coaxial shunt;

[0100] Assumptions:

[0101] The secondary current I output by the standard current transformer 标准 =1A,θ 标准 =0°;

[0102] The resistance of the coaxial shunt is R = 1Ω;

[0103] The voltage signal V converted by the coaxial shunt 被测 =1.02V,θ 被测 =5°. Then:

[0104]

[0105]

[0106] Phase difference = 0°-5° = -5°;

[0107] The evaluator evaluates the accuracy of the Rogowski coil tester using the ratio difference and the phase difference, specifically: judging whether the ratio difference does not exceed a first preset value and whether the phase difference does not exceed a second preset value. If both conditions are met, it indicates that the accuracy of the Rogowski coil tester is good.

[0108] In this embodiment, the first preset value is 1% and the second preset value is 3°. Therefore, when the ratio difference is less than or equal to 1% and the phase difference is less than or equal to 3°, it indicates that the accuracy of the Rogowski coil tester is good.

[0109] In the present invention, a standard current transformer is electrically connected to the output end of a primary current generator, and is used to generate an alternating magnetic flux through a measured current, and to induce a secondary current based on the alternating magnetic flux; a coaxial shunt has an input end connected to the output of the standard current transformer, and an output end connected to a Rogowski coil calibrator, and is used to convert the secondary current into a voltage signal and input the voltage signal into the Rogowski coil calibrator; the Rogowski coil calibrator is connected to the output of the standard current transformer, and is used to analyze the secondary current output by the standard current transformer and the voltage signal input by the coaxial shunt, that is, the present invention can realize calibration through a standard current transformer, avoids the use of two standard current sources, and reduces equipment cost and operation complexity.

[0110] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0111] In addition, in the present invention, descriptions such as "first", "second", "one", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0112] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0113] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Claims

1. An accuracy assessment device for a Rogowski coil tester, characterized in that: include: A primary current generator, used to generate the current to be measured; a standard current transformer, electrically connected to the output terminal of the primary current generator, for generating an alternating magnetic flux through the current to be measured, and inducing a secondary current based on the alternating magnetic flux; A coaxial shunt, whose input end is connected to the output of the standard current transformer and whose output end is connected to the Rogowski coil calibrator, is used to convert the secondary current into a voltage signal and input it into the Rogowski coil calibrator; The Rogowski coil tester is connected to the output of the standard current transformer and is used to analyze the secondary current output by the standard current transformer and the voltage signal input by the coaxial shunt.

2. The accuracy evaluation device for a Rogowski coil tester according to claim 1, characterized in that: The standard current transformer comprises: a primary side and a secondary side; wherein: The primary side is electrically connected to the output end of the primary current generator; the primary side is used to generate an alternating magnetic flux through the current to be measured; and the secondary side generates a secondary current through electromagnetic induction under the action of the alternating magnetic flux.

3. The accuracy evaluation device for a Rogowski coil tester according to claim 2, characterized in that: The primary side includes: a primary coil; The output end of the primary current generator outputs the measured current to the primary coil; the primary coil generates an alternating magnetic flux through the measured current.

4. The accuracy evaluation device for a Rogowski coil tester according to claim 3, characterized in that: The input end and the output end of the coaxial shunt both include a positive terminal and a negative terminal.

5. The accuracy evaluation device for a Rogowski coil tester according to claim 4, characterized in that: The secondary side includes: a secondary coil, and a positive connection terminal S1 arranged at the positive end of the secondary coil and a negative connection terminal S2 arranged at the negative end of the secondary coil; The secondary coil is connected to the positive pole of the Rogowski coil tester through the positive pole connection terminal S1 and is connected to the negative pole of the coaxial shunt input end through the negative pole connection terminal S2; the negative pole of the Rogowski coil tester is connected to the positive pole of the coaxial shunt input end; The secondary coil induces a secondary current based on the alternating magnetic flux generated by the primary coil and inputs the secondary current into the coaxial shunt and the Rogowski coil tester.

6. The accuracy evaluation device for a Rogowski coil tester according to claim 5, characterized in that: The Rogowski coil tester comprises: A standard signal input terminal, which is used to connect the secondary current induced by the secondary coil and input it into the coaxial shunt; the positive pole K1 of the standard signal input terminal is connected to the positive connection terminal S1, and the negative pole K2 is connected to the positive pole of the coaxial shunt input terminal; the negative pole of the coaxial shunt input terminal is connected to the negative connection terminal S2; The measured signal input terminal is used to access the voltage signal output by the coaxial shunt; the positive pole V1 of the measured signal input terminal is connected to the positive terminal of the coaxial shunt output terminal, and the negative pole V2 is connected to the negative terminal of the coaxial shunt output terminal.

7. The accuracy evaluation device for a Rogowski coil tester according to claim 1, characterized in that: The accuracy assessment device also includes: The evaluator connected to the output terminal of the Rogowski coil calibrator is used to receive the analysis result of the Rogowski coil calibrator and evaluate the accuracy of the Rogowski coil calibrator according to the analysis result.

8. The accuracy evaluation device for a Rogowski coil tester according to claim 6, characterized in that: The primary current generator comprises: A voltage regulator and a current booster; the input end of the voltage regulator is connected to a power supply, and the output end is connected to the input end of the current booster; the voltage regulator is used to adjust the voltage input to the current booster; the output end of the current booster is used to output the measured current to the primary coil; the measured current output by the current booster increases with the increase of the output voltage of the voltage regulator.

9. A method for evaluating the accuracy of a Rogowski coil tester, characterized in that: include: constructing an accuracy evaluation device, and forming a current loop through the accuracy evaluation device; The accuracy evaluation device comprises: a primary current generator; a standard current transformer electrically connected to the output end of the primary current generator; a coaxial shunt, an input end of which is connected to the output of the standard current transformer, and an output end of which is connected to a Rogowski coil tester; an evaluator connected to the output end of the Rogowski coil tester; the Rogowski coil tester is connected to the output of the standard current transformer; Generate the measured current through a primary current generator; The measured current generated by the primary current generator is used to generate an alternating magnetic flux through a standard current transformer, and a secondary current is induced based on the alternating magnetic flux; The secondary current output by the standard current transformer is connected through a coaxial shunt and converted into a voltage signal before being input into the Rogowski coil tester; The ratio difference and phase difference between the secondary current output by the standard current transformer and the voltage signal input by the coaxial shunt are calculated by using the Rogowski coil tester; The accuracy of the Rogowski coil tester is evaluated by an evaluator using ratio difference and phase difference.

10. The accuracy evaluation method for a Rogowski coil tester according to claim 9, characterized in that: The evaluator evaluates the accuracy of the Rogowski coil tester using the ratio difference and the phase difference, specifically: judging whether the ratio difference does not exceed a first preset value and whether the phase difference does not exceed a second preset value. If both conditions are met, it indicates that the accuracy of the Rogowski coil tester is good.

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