Current testing device and current testing method

Abstract

The invention discloses a current testing device and a current testing method, and relates to the technical field of current testing, and the device comprises a controller, a Rogowski coil assembly, an integrating circuit assembly, an amplifier assembly and a filter assembly. A controller for determining a target Rogowski coil, a target integrating circuit, a target amplifier, and a target filter based on the control signal, the coil information, the integrator information, the amplifier information, and the filter information; and the current test circuit generates a switching signal and controls the target Rogowski coil to be electrically connected with the target integrating circuit based on the switching signal, the target integrating circuit is electrically connected with the target amplifier, and the target amplifier is electrically connected with the target filter, so that the actual current value of the tested device is obtained based on the electrically connected current test circuit. The method and the device are used for solving the problems of poor accuracy and low efficiency during power semiconductor testing in the prior art, and the accuracy and the testing efficiency of power semiconductor testing are improved.

Description

Technical Field

[0001] The present application relates to the technical field of current testing, and in particular to a current testing device and a current testing method. Background Art

[0002] With the rapid development of power electronics technology, the performance and reliability of power semiconductor devices are critical in the design of various power systems, such as power conversion, drive control and energy management, electric systems, renewable energy systems, smart grids and industrial automation.

[0003] In the field of power semiconductor testing, it is necessary to test the dynamic performance of power semiconductors. Common dynamic parameter testing methods include: double pulse test and short circuit test. However, for the same power semiconductor, there is a large difference in the current generated under these two test conditions. Usually, the current generated by the short circuit test is 8 to 10 times the double pulse test current.

[0004] This significant current difference makes the current test device face challenges during the measurement process, and it is difficult to simultaneously meet the accurate measurement requirements under different test conditions. Usually, the Rogowski coil selected for short-circuit testing has a large range. When the same large-range Rogowski coil is used to test the small current of the double pulse test, it will cause a large deviation in the double pulse current waveform and it will be impossible to obtain accurate test results. If a small-range Rogowski coil is replaced, the attenuation ratio of the circuit and oscilloscope must be readjusted, which will greatly affect the efficiency of the test. Summary of the invention

[0005] In response to the above-mentioned problems and technical needs, the applicant has proposed a current testing device and a current testing method to solve the problems of poor accuracy and low efficiency in the prior art when performing power semiconductor testing, thereby improving the accuracy and testing efficiency of power semiconductor testing.

[0006] The embodiment of the present application provides a current testing device, the device comprising: a controller, a Rogowski coil component, an integration circuit component, an amplifier component and a filter component;

[0007] The Rogowski coil assembly includes: at least two Rogowski coils, the integration circuit assembly includes: at least two integration circuits, the amplifier assembly includes at least two amplifiers, and the filter assembly includes: at least two filters;

[0008] The controller is respectively connected to the Rogowski coil component, the integration circuit component, the amplifier component and the filter component;

[0009] The Rogowski coil component is electrically connected to the integration circuit component, the integration circuit component is electrically connected to the amplifier component, and the amplifier component is electrically connected to the filter component;

[0010] The controller is used to receive a control signal, coil information of the Rogowski coil assembly, integrator information of the integration circuit assembly, amplifier information of the amplifier assembly, and filter information of the filter assembly; based on the control signal, the coil information, the integrator information, the amplifier information, and the filter information, determine a target Rogowski coil from the Rogowski coil assembly, determine a target integration circuit from the integration circuit assembly, determine a target amplifier from the amplifier assembly, and determine a target filter from the filter assembly; generate a switching signal, and based on the switching signal, control the target Rogowski coil to be electrically connected to the target integration circuit, the target integration circuit to be electrically connected to the target amplifier, and the target amplifier to be electrically connected to the target filter, so as to obtain an actual current value of the device under test based on the current test circuit after electrical connection;

[0011] Wherein, the control signal includes: an estimated current value.

[0012] According to the current testing device of one embodiment of the present application, the controller is used to input the control signal, the coil information, the integrator information, the amplifier information and the filter information into a pre-trained neural network model to obtain the target Rogowski coil, the target integration circuit, the target amplifier and the target filter output by the neural network model;

[0013] The neural network model is trained based on control signal samples, coil information samples, integrator information samples, amplifier information samples, filter information samples and actual current value samples.

[0014] According to the current testing device of one embodiment of the present application, the controller is used to input the control signal, the coil information, the integrator information, the amplifier information and the filter information into the neural network model;

[0015] Extracting features of the control signal through a coding layer to obtain a first feature vector; splicing the first feature vector and the coil information to obtain first splicing information;

[0016] Inputting the first splicing information into the coil head layer to obtain a second eigenvector output by the coil head layer and used to characterize the target Rogowski coil; summing the first eigenvector and the second eigenvector to obtain a third eigenvector; splicing the third eigenvector and the integrator information to obtain second splicing information;

[0017] Inputting the second splicing information into the integrator head layer to obtain a fourth eigenvector output by the integrator head layer and used to characterize the target integration circuit; summing the third eigenvector and the fourth eigenvector to obtain a fifth eigenvector; splicing the fifth eigenvector and the amplifier information to obtain third splicing information;

[0018] Inputting the third splicing information into an amplifier head layer to obtain a sixth eigenvector output by the amplifier head layer and used to characterize the target amplifier; summing the fifth eigenvector and the sixth eigenvector to obtain a seventh eigenvector; splicing the seventh eigenvector and the filter information to obtain fourth splicing information;

[0019] Inputting the fourth splicing information into a filter head layer to obtain an eighth eigenvector output by the filter head layer and used to characterize the target filter;

[0020] The target Rogowski coil is obtained by analyzing the second eigenvector, the target integrating circuit is obtained by the fourth eigenvector, the target amplifier is obtained by the sixth eigenvector, and the target filter is obtained by the eighth eigenvector.

[0021] According to a current testing device of one embodiment of the present application, the first splicing information includes: splicing information of the first eigenvector and coil information corresponding to each Rogowski coil;

[0022] The second splicing information includes: splicing information of the third eigenvector and the integrator information corresponding to each integration circuit respectively;

[0023] The third splicing information includes: splicing information of the fifth eigenvector and amplifier information corresponding to each amplifier;

[0024] The fourth splicing information includes: splicing information of the seventh eigenvector and filter information corresponding to each filter.

[0025] According to a current testing device according to an embodiment of the present application, the training process of the neural network model includes:

[0026] Acquire a training sample data set, wherein the training sample data set includes: a control signal sample, a coil information sample, an integrator information sample, an amplifier information sample, a filter information sample, and an actual current value sample;

[0027] Inputting the training sample data set into a neural network model, and outputting a predicted Rogowski coil, a predicted integrator circuit, a predicted amplifier, and a predicted filter through the neural network model;

[0028] Electrically connecting the predicted Rogowski coil and the predicted integration circuit, the predicted integration circuit and the predicted amplifier, the predicted amplifier and the predicted filter to obtain a predicted current test circuit;

[0029] Obtaining a measured current value obtained based on the predicted current test circuit;

[0030] The consistency rate of the actual current value sample and the measured current value is compared, and the model parameters of the neural network model are adjusted based on the consistency rate until the number of adjustment iterations reaches a preset number, and it is determined that the training of the neural network model is completed.

[0031] According to a current testing device of an embodiment of the present application, the target Rogowski coil is used to be connected to the device under test to sense the electromotive force generated by the current of the device under test;

[0032] The target integration circuit is used to integrate the electromotive force induced by the target Rogowski coil to obtain a voltage signal proportional to the current of the device under test;

[0033] The target amplifier is used to amplify the voltage signal obtained by the target integration circuit to obtain an amplified voltage signal;

[0034] The target filter is used to filter the voltage signal obtained by the amplifier to obtain a final voltage signal.

[0035] According to a current testing device of an embodiment of the present application, the coil information includes: any one or more of the coil number, inductance value, number of coil turns, coil diameter and coil material of each Rogowski coil;

[0036] The integrator information includes: any one or more of the integrator number, time parameter, integration capacitance, integration resistance and frequency response of each integrator;

[0037] The amplifier information includes: any one or more of the amplifier number, gain, bandwidth and phase response of each amplifier;

[0038] The filter information includes: any one or more of the filter number, cutoff frequency and filter order of each filter.

[0039] According to the current testing device of one embodiment of the present application, the control signal further includes: test duration.

[0040] The present application also provides a current testing method, which is applied to the current testing device described in any of the above embodiments, and the method includes:

[0041] receiving a control signal, coil information, integrator information, amplifier information and filter information corresponding to the current testing device, wherein the control signal includes: an estimated current value;

[0042] determining a target Rogowski coil, a target integrator circuit, a target amplifier, and a target filter from the current testing device based on the control signal, the coil information, the integrator information, the amplifier information, and the filter information;

[0043] A switching signal is generated, and based on the switching signal, the target Rogowski coil is controlled to be electrically connected to the target integration circuit, the target integration circuit is electrically connected to the target amplifier, and the target amplifier is electrically connected to the target filter, so as to obtain an actual current value of the device under test based on the current test circuit after the electrical connection.

[0044] According to an embodiment of the present application, the current testing method further includes, after receiving the control signal:

[0045] Obtain the compensation current value corresponding to the current test condition;

[0046] The estimated current value is compensated based on the compensation current value to obtain a compensated estimated current value.

[0047] The current testing device and current testing method provided by the embodiments of the present application include: a controller, a Rogowski coil assembly, an integration circuit assembly, an amplifier assembly and a filter assembly. The present application determines the target Rogowski coil from the Rogowski coil assembly, determines the target integration circuit from the integration circuit assembly, determines the target amplifier from the amplifier assembly, and determines the target filter from the filter assembly based on the estimated current value, coil information, integrator information, amplifier information and filter information. It can be seen that the current testing device of the present application can adapt to currents of various ranges and can quickly and effectively obtain a target device that matches the estimated current value; and can control the target Rogowski coil to be electrically connected to the target integration circuit, the target integration circuit to be electrically connected to the target amplifier, and the target amplifier to be electrically connected to the target filter based on the generated switching signal to obtain a current testing circuit, thereby realizing automatic switching of the current testing circuit, the purpose of which is to switch to a current testing circuit that matches the estimated current value, and obtain the actual current value of the device under test based on the current testing circuit after electrical connection, thereby solving the problems of poor accuracy and low efficiency in the prior art when performing power semiconductor testing, and improving the accuracy and test efficiency of power semiconductor testing.

[0048] The current testing device of the present application can automatically switch between multi-range current testing circuits and can simultaneously meet the measurement requirements of dual pulse testing and short-circuit testing. That is, through the switching mechanism, it can quickly adapt to different test conditions without replacing the current testing device, thereby achieving efficient and accurate measurement of the dynamic parameters of power semiconductors and improving the current testing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0050] Figure 1 is a structural schematic diagram of a current testing device provided in an embodiment of the present application;

[0051] Figure 2 is a circuit diagram of a current testing device provided in an embodiment of the present application;

[0052] Figure 3 It is a structural schematic diagram of a neural network model provided in an embodiment of the present application;

[0053] Figure 4 It is a flow chart of the current testing method provided in the embodiment of the present application. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] The present application embodiment provides a current testing device, such as Figure 1 As shown, the device includes: a controller 101 , a Rogowski coil component 102 , an integration circuit component 103 , an amplifier component 104 and a filter component 105 .

[0056] The Rogowski coil assembly 102 includes at least two Rogowski coils, the integration circuit assembly 103 includes at least two integration circuits, the amplifier assembly 104 includes at least two amplifiers, and the filter assembly 105 includes at least two filters.

[0057] The controller 101 is connected to the Rogowski coil assembly 102 , the integrating circuit assembly 103 , the amplifier assembly 104 and the filter assembly 105 respectively.

[0058] The Rogowski coil assembly 102 is electrically connected to the integration circuit assembly 103 , the integration circuit assembly 103 is electrically connected to the amplifier assembly 104 , and the amplifier assembly 104 is electrically connected to the filter assembly 105 .

[0059] The controller 101 is used to receive a control signal, coil information of a Rogowski coil assembly 102, integrator information of an integration circuit assembly 103, amplifier information of an amplifier assembly 104, and filter information of a filter assembly 105; based on the control signal, coil information, integrator information, amplifier information, and filter information, determine a target Rogowski coil from the Rogowski coil assembly 102, determine a target integration circuit from the integration circuit assembly 103, determine a target amplifier from the amplifier assembly 104, and determine a target filter from the filter assembly 105; generate a switching signal, and based on the switching signal, control the target Rogowski coil to be electrically connected to the target integration circuit, the target integration circuit to be electrically connected to the target amplifier, and the target amplifier to be electrically connected to the target filter, so as to obtain an actual current value of the device under test based on the current test circuit after electrical connection.

[0060] Wherein, the control signal includes: an estimated current value.

[0061] The device under test includes a power semiconductor.

[0062] Among them, Figure 1 Two Rogowski coils, two integrating circuits, two amplifiers and two filters are used as examples for illustration, which are only examples and are not used to limit the protection scope of the present application.

[0063] Among them, through Figure 2 The circuit diagram of the current test device is shown below. Figure 2 Here, MCU represents the controller 101, letter I represents the current of the device under test, and Vout represents the output voltage.

[0064] Specifically, a Rogowski coil is usually composed of one or more turns of winding wire, which is in the shape of a ring, and the inside of the coil is open without an iron core. This design allows the Rogowski coil to not interfere with the flow of the measured current during the measurement process. According to Faraday's law of electromagnetic induction, a changing magnetic field will induce an electromotive force in a closed loop. The measurement principle of the Rogowski coil can be summarized as follows: when an alternating current passes through a conductor, a changing magnetic field is generated around the conductor; the Rogowski coil is located in this magnetic field, and the change in the magnetic field will induce an electromotive force in the Rogowski coil, and the induced electromotive force is proportional to the rate of change of the current in the conductor.

[0065] Specifically, the control signal can communicate with the controller 101 through a variety of communication methods, such as serial port, network port, GPIB, etc. The control signal includes any signal that can represent control information, such as a level signal (e.g., rising edge, falling edge, high and low level, etc.), and the controller 101 parses the estimated current value through the change of the level signal.

[0066] The current testing device provided in the embodiment of the present application includes: a controller, a Rogowski coil assembly, an integration circuit assembly, an amplifier assembly and a filter assembly. The present application determines the target Rogowski coil from the Rogowski coil assembly, determines the target integration circuit from the integration circuit assembly, determines the target amplifier from the amplifier assembly, and determines the target filter from the filter assembly based on the estimated current value, coil information, integrator information, amplifier information and filter information. It can be seen that the current testing device of the present application can adapt to currents of various ranges and can quickly and effectively obtain a target device that matches the estimated current value; and can control the target Rogowski coil to be electrically connected to the target integration circuit, the target integration circuit to be electrically connected to the target amplifier, and the target amplifier to be electrically connected to the target filter based on the generated switching signal to obtain a current testing circuit, thereby realizing automatic switching of the current testing circuit, the purpose of which is to switch to a current testing circuit that matches the estimated current value, and obtain the actual current value of the device under test based on the current testing circuit after electrical connection, thereby solving the problems of poor accuracy and low efficiency in the prior art when performing power semiconductor testing, and improving the accuracy and test efficiency of power semiconductor testing.

[0067] The current testing device of the present application can automatically switch between multi-range current testing circuits and can simultaneously meet the measurement requirements of dual pulse testing and short-circuit testing. That is, through the switching mechanism, it can quickly adapt to different test conditions without replacing the current testing device, thereby achieving efficient and accurate measurement of the dynamic parameters of power semiconductors and improving the current testing efficiency.

[0068] In a specific embodiment, the control signal also includes: test duration.

[0069] The test duration is used to characterize the test duration of the current test of the device under test, and has no influence on the determination of the current test circuit.

[0070] In a specific embodiment, the coil information includes: any one or more of the coil number, inductance, number of coil turns, coil diameter, and coil material of each Rogowski coil. The integrator information includes: any one or more of the integrator number, time parameter, integral capacitance, integral resistance, and frequency response of each integrator. The amplifier information includes: any one or more of the amplifier number, gain, bandwidth, and phase response of each amplifier. The filter information includes: any one or more of the filter number, cutoff frequency, and filter order of each filter.

[0071] In a specific embodiment, the controller 101 is used to input the control signal, coil information, integrator information, amplifier information and filter information into a pre-trained neural network model to obtain the target Rogowski coil, target integrator circuit, target amplifier and target filter output by the neural network model.

[0072] The neural network model is trained based on control signal samples, coil information samples, integrator information samples, amplifier information samples, filter information samples and actual current value samples.

[0073] In a specific embodiment, the training process of the neural network model includes:

[0074] Acquire a training sample data set; input the training sample data set into a neural network model, and output a predicted Rogowski coil, a predicted integration circuit, a predicted amplifier, and a predicted filter through the neural network model; electrically connect the predicted Rogowski coil and the predicted integration circuit, the predicted integration circuit and the predicted amplifier, and the predicted amplifier and the predicted filter to obtain a predicted current test circuit; obtain a measured current value obtained based on the predicted current test circuit; compare the consistency rate of the actual current value sample and the measured current value, and adjust the model parameters of the neural network model based on the consistency rate until the number of adjustment iterations reaches a preset number, and determine that the neural network model training is completed.

[0075] The training sample data set includes: control signal samples, coil information samples, integrator information samples, amplifier information samples, filter information samples and actual current value samples.

[0076] Specifically, the model parameters of the neural network model are adjusted by calculating the error between the actual current value sample and the measured current value.

[0077] Specifically, during the neural network model training phase, actual current values ​​and configuration information (target Rogowski coil, target integration circuit, target amplifier, target filter, and the connection relationship between each device) under various circuit configurations (current test circuit) under different currents (fixed-end current values) are collected.

[0078] For example, when performing a double pulse test, the current peak value (estimated current value) generated by the device under test will be estimated based on the set double pulse parameters. At this time, the current waveform of the double pulse can be simulated as the input of the Rogowski coil. For example, assuming a fixed pulse current of 10A and a pulse width of 20 microseconds, a variety of current test circuits to be selected are combined using Rogowski coils with different coil turns, integration circuits with different parameters, amplifiers with different amplification factors, and filters with different filtering ranges. The pulse current can be measured.

[0079] At this time, each combination can be used as a training sample. Then, a large number of training samples can be obtained by modifying the pulse current value.

[0080] Specifically, considering the response speed of the model, the head layer of the neural network model of the present application adopts a long short-term memory neural network (LSTM) and other network layers are implemented with full connection, and the number of network nodes in each layer is small, for example, 64 nodes or 128 nodes.

[0081] The present application can quickly and accurately obtain a current test circuit that matches the control signal by pre-training a neural network model.

[0082] In a specific embodiment, the controller 101 is used to input the control signal, coil information, integrator information, amplifier information and filter information into the neural network model. The control signal is feature extracted through the coding layer to obtain a first feature vector; the first feature vector and the coil information are spliced ​​to obtain first splicing information. The first splicing information is input into the coil head layer to obtain a second feature vector output by the coil head layer for characterizing the target Rogowski coil; the first feature vector and the second feature vector are summed to obtain a third feature vector; the third feature vector and the integrator information are spliced ​​to obtain second splicing information. The second splicing information is input into the integrator head layer to obtain a fourth feature vector output by the integrator head layer for characterizing the target integration circuit; the third feature vector and the fourth feature vector are summed to obtain a fifth feature vector; the fifth feature vector and the amplifier information are spliced ​​to obtain third splicing information. The third splicing information is input into the amplifier head layer to obtain the sixth eigenvector output by the amplifier head layer for characterizing the target amplifier; the fifth eigenvector and the sixth eigenvector are summed to obtain the seventh eigenvector; the seventh eigenvector and the filter information are spliced ​​to obtain the fourth splicing information. The fourth splicing information is input into the filter head layer to obtain the eighth eigenvector output by the filter head layer for characterizing the target filter.

[0083] The target Rogowski coil is obtained by analyzing the second eigenvector, the target integrating circuit is obtained by the fourth eigenvector, the target amplifier is obtained by the sixth eigenvector, and the target filter is obtained by the eighth eigenvector.

[0084] Specifically, after obtaining the second eigenvector, the second eigenvector is analyzed by the first decoding layer to obtain the target Rogowski coil; after obtaining the fourth eigenvector, the fourth eigenvector is analyzed by the second decoding layer to obtain the target integration circuit; after obtaining the sixth eigenvector, the sixth eigenvector is analyzed by the third decoding layer to obtain the target amplifier; after obtaining the eighth eigenvector, the eighth eigenvector is analyzed by the fourth decoding layer to obtain the target filter.

[0085] In a specific embodiment, the first splicing information includes: the splicing information of the first eigenvector and the coil information corresponding to each Rogowski coil; the second splicing information includes: the splicing information of the third eigenvector and the integrator information corresponding to each integration circuit; the third splicing information includes: the splicing information of the fifth eigenvector and the amplifier information corresponding to each amplifier; the fourth splicing information includes: the splicing information of the seventh eigenvector and the filter information corresponding to each filter.

[0086] Specifically, the concatenation operation of the coil information, integrator information, amplifier information, and filter information with the feature vector output by the previous stage is the same, and the operation of the concatenated information passing through the head layer and then passing through the decoding layer to obtain the decoding result is also the same. Therefore, the coil information is used as an example here for explanation, and other devices can be deduced by analogy:

[0087] The coil number, inductance, number of turns, coil diameter and coil material of each Rogowski coil are integrated into a coil vector C. Multiple Rogowski coils will have multiple coil vectors (corresponding to coil information). For example, C n Represents, where 1<=n<=N, where N represents the number of Rogowski coils.

[0088] The first eigenvector and coil information are concatenated, that is, H is merged with C1, H is merged with C2, H is merged with C3, ..., H is merged with C N Merge. Where H represents the first eigenvector, which is a one-dimensional vector, and C n is also a one-dimensional vector. Finally, the N vectors are merged to obtain the first concatenated information Q. The dimension of Q is (1, N, H+C).

[0089] The merging order of the vectors is the order in which the coil numbers of the Rogowski coils are arranged from small to large.

[0090] The dimension of the second feature vector M after the coil head layer calculation is (1, N, H). M is reshaped to a vector of (1*N, H), and then the decoding layer is used to calculate the vector J of dimension (N, 1). The vector J is converted into a probability distribution with values ​​between 0 and 1 by performing a Softmax operation on the vector J, and the Rogowski coil corresponding to the index number corresponding to the maximum probability is determined as the target Rogowski coil. The index number of the vector J is the same as the index number of the vector Q.

[0091] The second eigenvector also includes the first eigenvector.

[0092] Among them, Figure 3 As shown, the neural network model includes: an encoding layer, a coil head layer, a first decoding layer, a coil selection result output layer, a first fusion layer, an integrator head layer, a second decoding layer, an integrator selection result output layer, a second fusion layer, an amplifier head layer, a third decoding layer, an amplifier selection result output layer, a third fusion layer, a filter head layer, a fourth decoding layer and a filter selection result output layer.

[0093] In a specific embodiment, the target Rogowski coil is used to connect to the device under test to sense the electromotive force generated by the current of the device under test; the target integration circuit is used to integrate the electromotive force induced by the target Rogowski coil to obtain a voltage signal proportional to the current of the device under test; the target amplifier is used to amplify the voltage signal obtained by the target integration circuit to obtain an amplified voltage signal; the target filter is used to filter the voltage signal obtained by the amplifier to obtain a final voltage signal.

[0094] Specifically, the function of the Rogowski coil is as follows: According to Ampere's loop theorem and Faraday's law of electromagnetic induction, the loop current will generate a magnetic field, and the Rogowski coil can induce an electromotive force according to the change of the magnetic field. The magnitude of the induced electromotive force can be changed by increasing or decreasing the number of turns of the Rogowski coil. The more turns the higher the induced voltage of the Rogowski coil, the more suitable it is for measuring higher currents; conversely, fewer turns are suitable for measuring lower currents. Therefore, the current measurement range can be changed by adding a variety of Rogowski coils with different numbers of turns.

[0095] The function of the integration circuit is to integrate the voltage signal induced by the Rogowski coil to obtain an output signal proportional to the actual current. The integration time constant can be adjusted by changing the resistance and capacitance values ​​in the integration circuit, thereby changing the range to a certain extent. Among them, the parameter adjustment of the integration circuit depends to a certain extent on the parameters of the Rogowski coil. Therefore, the design of the integration circuit should be compatible with Rogowski coils with different numbers of turns.

[0096] The function of the amplifier is to amplify the weak voltage signal induced by the Rogowski coil to make it within the measurable range. By changing the gain of the amplifier, the measurement range can be expanded or reduced. By setting amplifiers with different gains, different current measurement ranges can be set.

[0097] The function of the filter is to suppress high-frequency noise and interference signals to ensure the purity and accuracy of the measured signal. A variety of filters are designed to adapt to different types of interference signals, which basically do not affect the range of current measurement.

[0098] Specifically, a rapidly changing current signal is induced by the Rogowski coil, and the induced voltage signal is integrated through an integration circuit to obtain a voltage signal proportional to the actual current. The voltage signal is then filtered and amplified through a filter and an amplifier, and transmitted to an oscilloscope for display.

[0099] The Rogowski coil switches the range by changing the number of turns. When it receives a signal from the controller, the coil of the corresponding range will be connected to the measurement circuit, and it generates an electromotive force by inducing the rapidly changing measured current. The integration circuit switches the range by adjusting the integration time constant. When it receives a signal from the controller, the integration circuit of the corresponding range will be connected to the measurement circuit, which integrates the electromotive force induced by the Rogowski coil to obtain a voltage signal proportional to the measured current. The amplifier switches the range by changing the amplification gain. When it receives a signal from the controller, the amplifier of the corresponding range will be connected to the measurement circuit, which amplifies the filtered voltage signal and inputs it into the oscilloscope for voltage acquisition and display. The filter is switched according to the noise type of the current, and it is difficult to directly change the size of the range. When it receives a signal from the controller, a filter with a better filtering effect will be connected to the measurement circuit, which filters the voltage signal generated by the circuit to obtain a purer voltage signal and reduce the impact of noise.

[0100] The integration circuit used in the embodiment is a first-order active RC integration circuit.

[0101] The amplifier used in the embodiment is a first-order proportional amplifier.

[0102] The filter used in the embodiment is a first-order low-pass filter.

[0103] The present application can realize accurate measurement of current and a wider measurement range: by switching the Rogowski coil range, the optimal range selection under different current measurements can be achieved, ensuring high-precision measurement in different current ranges and reducing errors.

[0104] The present application can effectively increase the measurement efficiency: when the measured current changes by a large order of magnitude, a Rogowski coil of an inappropriate range will produce a large error, and usually it is necessary to manually replace the Rogowski coil of other ranges, which greatly affects the measurement efficiency. This problem can be avoided by automatically switching multi-range Rogowski coils, while also reducing costs.

[0105] This application can effectively improve the safety of the equipment: in high current testing, if the range is not set properly, it may cause damage to the measuring equipment and the equipment under test. The automatic range switching can automatically select the appropriate range according to the current size, avoiding equipment damage caused by improper range setting, and improving the safety of the overall test system.

[0106] This application is suitable for a variety of test scenarios: the automatically switched multi-range Rogowski coil can flexibly adapt to various test scenarios without the need to replace different measuring equipment, thereby improving the versatility and adaptability of the test system.

[0107] This application uses a neural network model to calculate the optimal current measurement circuit configuration under different working conditions, thereby improving the response speed and accuracy of the controller.

[0108] The present application also provides a current testing method, which is applied to the current testing device described in any of the above embodiments, and the repetitive parts are not repeated here. Figure 4 As shown, the method includes:

[0109] Step 401, receiving a control signal, coil information, integrator information, amplifier information and filter information corresponding to a current testing device.

[0110] Wherein, the control signal includes: an estimated current value.

[0111] Step 402 : determining a target Rogowski coil, a target integrator circuit, a target amplifier, and a target filter from a current testing device based on the control signal, the coil information, the integrator information, the amplifier information, and the filter information.

[0112] Step 403, generating a switching signal, and based on the switching signal, controlling the target Rogowski coil to be electrically connected to the target integration circuit, the target integration circuit to be electrically connected to the target amplifier, and the target amplifier to be electrically connected to the target filter, so as to obtain the actual current value of the device under test based on the current test circuit after electrical connection.

[0113] In a specific embodiment, after receiving the control signal, a compensation current value corresponding to the current test condition is obtained; and the estimated current value is compensated based on the compensation current value to obtain the compensated estimated current value.

[0114] Specifically, a mapping relationship between the test conditions and the compensation current value is preset.

[0115] Among them, the test condition includes estimating the current value.

[0116] On the other hand, the present invention also provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute the current testing methods provided by the above methods.

[0117] On the other hand, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which is implemented when the computer program is executed by a processor to perform the current testing method provided in the above embodiments.

[0118] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0119] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0120] Finally, it should be noted that the above is only the preferred implementation of the present application, and the present application is not limited to the above embodiments. It is understood that other improvements and changes directly derived or associated by those skilled in the art without departing from the spirit and concept of the present application should be considered to be included in the scope of protection of the present application.

Claims

1. A current testing device, characterized in that: The device comprises: a controller, a Rogowski coil component, an integration circuit component, an amplifier component and a filter component; The Rogowski coil assembly includes: at least two Rogowski coils, the integration circuit assembly includes: at least two integration circuits, the amplifier assembly includes at least two amplifiers, and the filter assembly includes: at least two filters; The controller is respectively connected to the Rogowski coil component, the integration circuit component, the amplifier component and the filter component; The Rogowski coil component is electrically connected to the integration circuit component, the integration circuit component is electrically connected to the amplifier component, and the amplifier component is electrically connected to the filter component; The controller is used to receive a control signal, coil information of the Rogowski coil assembly, integrator information of the integration circuit assembly, amplifier information of the amplifier assembly, and filter information of the filter assembly; based on the control signal, the coil information, the integrator information, the amplifier information, and the filter information, determine a target Rogowski coil from the Rogowski coil assembly, determine a target integration circuit from the integration circuit assembly, determine a target amplifier from the amplifier assembly, and determine a target filter from the filter assembly; generate a switching signal, and based on the switching signal, control the target Rogowski coil to be electrically connected to the target integration circuit, the target integration circuit to be electrically connected to the target amplifier, and the target amplifier to be electrically connected to the target filter, so as to obtain an actual current value of the device under test based on the current test circuit after electrical connection; Wherein, the control signal includes: an estimated current value.

2. The current testing device according to claim 1, characterized in that: The controller is used to input the control signal, the coil information, the integrator information, the amplifier information and the filter information into a pre-trained neural network model to obtain the target Rogowski coil, the target integrator circuit, the target amplifier and the target filter output by the neural network model; The neural network model is trained based on control signal samples, coil information samples, integrator information samples, amplifier information samples, filter information samples and actual current value samples.

3. The current testing device according to claim 2, characterized in that: The controller is used to input the control signal, the coil information, the integrator information, the amplifier information and the filter information into the neural network model; Extracting features of the control signal through a coding layer to obtain a first feature vector; splicing the first feature vector and the coil information to obtain first splicing information; Inputting the first splicing information into the coil head layer to obtain a second eigenvector output by the coil head layer and used to characterize the target Rogowski coil; summing the first eigenvector and the second eigenvector to obtain a third eigenvector; splicing the third eigenvector and the integrator information to obtain second splicing information; Inputting the second splicing information into the integrator head layer to obtain a fourth eigenvector output by the integrator head layer and used to characterize the target integration circuit; summing the third eigenvector and the fourth eigenvector to obtain a fifth eigenvector; splicing the fifth eigenvector and the amplifier information to obtain third splicing information; Inputting the third splicing information into an amplifier head layer to obtain a sixth eigenvector output by the amplifier head layer and used to characterize the target amplifier; summing the fifth eigenvector and the sixth eigenvector to obtain a seventh eigenvector; splicing the seventh eigenvector and the filter information to obtain fourth splicing information; Inputting the fourth splicing information into a filter head layer to obtain an eighth eigenvector output by the filter head layer and used to characterize the target filter; The target Rogowski coil is obtained by analyzing the second eigenvector, the target integrating circuit is obtained by the fourth eigenvector, the target amplifier is obtained by the sixth eigenvector, and the target filter is obtained by the eighth eigenvector.

4. The current testing device according to claim 3, characterized in that: The first splicing information includes: splicing information of the first characteristic vector and coil information corresponding to each Rogowski coil; The second splicing information includes: splicing information of the third eigenvector and the integrator information corresponding to each integration circuit respectively; The third splicing information includes: splicing information of the fifth eigenvector and amplifier information corresponding to each amplifier; The fourth splicing information includes: splicing information of the seventh eigenvector and filter information corresponding to each filter.

5. The current testing device according to any one of claims 1 to 4, characterized in that: The training process of the neural network model includes: Acquire a training sample data set, wherein the training sample data set includes: a control signal sample, a coil information sample, an integrator information sample, an amplifier information sample, a filter information sample, and an actual current value sample; Inputting the training sample data set into a neural network model, and outputting a predicted Rogowski coil, a predicted integrator circuit, a predicted amplifier, and a predicted filter through the neural network model; Electrically connecting the predicted Rogowski coil and the predicted integration circuit, the predicted integration circuit and the predicted amplifier, the predicted amplifier and the predicted filter to obtain a predicted current test circuit; Obtaining a measured current value obtained based on the predicted current test circuit; The consistency rate of the actual current value sample and the measured current value is compared, and the model parameters of the neural network model are adjusted based on the consistency rate until the number of adjustment iterations reaches a preset number, and it is determined that the training of the neural network model is completed.

6. The current testing device according to any one of claims 1 to 4, characterized in that: The target Rogowski coil is used to connect to the device under test and sense the electromotive force generated by the current of the device under test; The target integration circuit is used to integrate the electromotive force induced by the target Rogowski coil to obtain a voltage signal proportional to the current of the device under test; The target amplifier is used to amplify the voltage signal obtained by the target integration circuit to obtain an amplified voltage signal; The target filter is used to filter the voltage signal obtained by the amplifier to obtain a final voltage signal.

7. The current testing device according to any one of claims 1 to 4, characterized in that: The coil information includes: any one or more of the coil number, inductance value, number of coil turns, coil diameter and coil material of each Rogowski coil; The integrator information includes: any one or more of the integrator number, time parameter, integration capacitance, integration resistance and frequency response of each integrator; The amplifier information includes: any one or more of the amplifier number, gain, bandwidth and phase response of each amplifier; The filter information includes: any one or more of the filter number, cutoff frequency and filter order of each filter.

8. The current testing device according to any one of claims 1 to 4, characterized in that: The control signal also includes: test duration.

9. A current testing method, characterized in that: Applied to the current testing device according to any one of claims 1 to 8, the method comprises: receiving a control signal, coil information, integrator information, amplifier information and filter information corresponding to the current testing device, wherein the control signal includes: an estimated current value; determining a target Rogowski coil, a target integrator circuit, a target amplifier, and a target filter from the current testing device based on the control signal, the coil information, the integrator information, the amplifier information, and the filter information; A switching signal is generated, and based on the switching signal, the target Rogowski coil is controlled to be electrically connected to the target integration circuit, the target integration circuit is electrically connected to the target amplifier, and the target amplifier is electrically connected to the target filter, so as to obtain an actual current value of the device under test based on the current test circuit after the electrical connection.

10. The current testing method according to claim 9, characterized in that: After receiving the control signal, it also includes: Obtain the compensation current value corresponding to the current test condition; The estimated current value is compensated based on the compensation current value to obtain a compensated estimated current value.

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