A transformer testing device and tester based on double DSP chips

Abstract

The application discloses a transformer testing device and tester based on double DSP chips, which is used for improving the speed and precision of transformer data sampling. The device comprises a first DSP chip, a second DSP chip, a high-pass filter module, an amplification circuit, a first AD conversion circuit, a second AD conversion circuit, a first signal acquisition module, a second signal acquisition module, a logic circuit module, a data storage and a USB communication interface. The application generates a sine wave signal with a preset frequency point as an excitation signal through the second DSP chip, generates a square wave with a preset frequency multiplication through the first DSP chip, and samples signals from the data storage according to the square wave with the preset frequency multiplication, so that the double DSP design is realized, the existing single DSP chip design is improved, high-speed sampling is realized, data overlap is avoided, the influence on data precision is reduced, the integrated cost is reduced, and the practical application value is improved.

Description

Technical Field

[0001] This invention relates to the field of transformer testing technology, and in particular to a transformer testing device and instrument based on dual DSP chips. Background Technology

[0002] Transformers are one of the main pieces of equipment in a power system, and their performance directly affects the safe operation of the power system. Therefore, monitoring the operating status of transformers, especially preventative testing, is particularly important. Currently, there are two methods for preventative testing of transformers both domestically and internationally: one is using a comprehensive transformer testing platform; the other is using specialized instruments for various testing items. However, the first method involves a large and heavy comprehensive transformer testing platform (weighing hundreds of kilograms), and since transformers are often installed in a dispersed manner in distribution networks, it is inconvenient to carry them outdoors for testing, making it only suitable for laboratory testing and research. The second method, which involves carrying several specialized testing instruments to perform different tests, is currently the main method for preventative transformer testing.

[0003] Currently, the hardware implementation of transformer testers both domestically and internationally mainly falls into two categories: one is microprocessors including DSPs or microcontrollers, and the other is industrial control computer technology based on virtual instruments. Single microprocessors are the most commonly used in China. However, due to their limited clock speed, single microprocessors struggle to perform high-speed sampling and lack a good human-machine interface. Summary of the Invention

[0004] This invention provides a transformer testing device and instrument based on dual DSP chips, which can improve the speed and accuracy of transformer data sampling.

[0005] This invention provides a transformer testing device based on a dual-DSP chip, comprising:

[0006] First DSP chip, second DSP chip, high-pass filter module, amplifier circuit, first AD conversion circuit, second AD conversion circuit, first signal acquisition module, second signal acquisition module, logic circuit module, data storage, USB communication interface;

[0007] The second DSP chip is connected to the high-pass filter module; the high-pass filter module is connected to the amplifier circuit.

[0008] The first AD conversion circuit is connected to the first signal acquisition module;

[0009] The second AD conversion circuit is connected to the second signal acquisition module;

[0010] The second signal acquisition module, the first AD conversion circuit, and the second AD conversion circuit are respectively connected to the logic circuit module;

[0011] The logic circuit module, the first AD conversion circuit, and the second AD conversion circuit are connected to the data memory.

[0012] The data storage is connected to the first DSP chip via a data address bus;

[0013] The logic circuit module is connected to the first DSP chip via a control bus;

[0014] The first DSP chip is connected to the USB communication interface;

[0015] The first DSP chip is used to generate a square wave with a preset frequency multiplication factor;

[0016] The second DSP chip is used to generate a sine wave signal at a preset frequency.

[0017] The present invention also provides a transformer tester, the tester comprising: a central control module, a DC resistance test module, an AC resistance test module, a transformer turns ratio test module, an AC parameter test module, and a central control module;

[0018] The DC resistance test module, the AC resistance test module, the transformer turns ratio test module, and the AC parameter test module are connected to the central control module via an RS485 bus.

[0019] The DC resistance test module, the AC resistance test module, the transformer turns ratio test module, and the AC parameter test module are each integrated by a test device.

[0020] Optionally, the DC test module is used to test the DC resistance parameters of the transformer under test.

[0021] Optionally, the AC resistance testing module is used to test the insulation resistance parameters of the transformer under test.

[0022] Optionally, the transformer turns ratio test module is used to test the turns ratio parameters of the transformer.

[0023] Optionally, the AC parameter testing module is used to test the loss parameters and power frequency withstand voltage parameters of the transformer under test.

[0024] Optionally, the tester further includes a constant current source;

[0025] The constant current source is connected to the DC resistance test module, the AC resistance test module, the transformer turns ratio test module, and the AC parameter test module, respectively.

[0026] Optionally, the tester also includes a display screen;

[0027] The central control module is connected to the display screen.

[0028] Optionally, the tester also includes a printer;

[0029] The central control module is connected to the printer.

[0030] Optionally, the central control module is connected to a computer.

[0031] As can be seen from the above technical solutions, the present invention has the following advantages:

[0032] One aspect of this invention discloses a transformer testing device based on dual DSP chips, comprising a first DSP chip, a second DSP chip, a high-pass filter module, an amplifier circuit, a first AD conversion circuit, a second AD conversion circuit, a first signal acquisition module, a second signal acquisition module, a logic circuit module, a data storage device, and a USB communication interface. In this embodiment, an excitation signal is generated and output by a second DSP chip. This excitation signal is used to test the parameter characteristics of the transformer under test. The second DSP chip also generates a standard input signal corresponding to the excitation signal and sends it to a first signal acquisition module. The second signal acquisition module receives the response input signal from the transformer under test under the action of the excitation signal. The first DSP chip outputs control instructions to a logic circuit module. The logic circuit module outputs timing instructions to a first AD conversion circuit and a second AD conversion circuit, causing the first and second AD conversion circuits to transmit the standard input signal and the response input signal to a data memory according to the timing instructions. The first DSP chip generates a square wave with a preset frequency multiplication and acquires the standard input signal data and response input signal data from the data memory based on the square wave. This achieves high-speed sampling of the test data and avoids data overlap, which affects data accuracy. The first DSP chip analyzes the transformer characteristic parameters based on the standard input signal data and the response input signal data and outputs the analyzed transformer characteristic parameter results through a USB communication interface, thus realizing the testing of the transformer characteristic parameters.

[0033] In this embodiment, a sinusoidal signal at a preset frequency is generated by the second DSP chip as the excitation signal, and a square wave with a preset multiplier is generated by the first DSP chip. The signal is sampled from the data memory according to the square wave with the preset multiplier, thus realizing a dual-DSP design. This improves the existing single DSP chip design. Furthermore, through the structure and data interaction of the first DSP chip, logic circuit module, and data memory, high-speed sampling is achieved, and data overlap is avoided, which affects data accuracy. At the same time, the cost of integration is reduced, and the practical application value is improved.

[0034] Another aspect of the present invention provides a transformer tester, comprising: a central control module, a DC resistance test module, an AC resistance test module, a transformer turns ratio test module, an AC parameter test module, and a central control module;

[0035] The DC resistance test module, the AC resistance test module, the transformer turns ratio test module, and the AC parameter test module are connected to the central control module via an RS485 bus.

[0036] The DC resistance test module, the AC resistance test module, the transformer turns ratio test module, and the AC parameter test module are all integrated by the aforementioned test devices.

[0037] In this embodiment, each test module is integrated with a corresponding test device. Therefore, by employing test modules integrated with a dual-DSP chip transformer test device, each test module possesses high-speed data sampling capabilities and independent data processing functions. Furthermore, integrating these test modules into the test instrument achieves the integration and unification of multiple different test functions, improving transformer testing efficiency and avoiding the problem in existing transformer testing where multiple dedicated instruments are required to test a single test item. This provides a more portable test instrument with multiple testing functions. Moreover, in this embodiment, each test module transmits test data to the central control module via an RS485 bus. The central control module manages the test data obtained by each test module, avoiding the inconvenience of data management after testing caused by different test instruments from different manufacturers and incomplete data communication between them, which is common in existing transformer testing. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram of a transformer testing device based on dual DSP chips provided in an embodiment of the present invention;

[0040] Figure 2 This is a schematic diagram of the structure of a transformer tester provided in an embodiment of the present invention;

[0041] Figure 3 This invention provides a schematic diagram of the rear panel assembly structure of a transformer tester according to an embodiment of the present invention;

[0042] Figure 4 This invention provides a schematic diagram of the front panel assembly structure of a transformer tester according to an embodiment of the present invention;

[0043] Figure 5 This invention provides a schematic diagram of the internal assembly structure of a transformer tester according to an embodiment of the present invention;

[0044] Figure 6 This invention provides a schematic diagram of the internal assembly structure of a transformer tester according to an embodiment of the present invention;

[0045] Figure 7 This is a schematic diagram of the internal assembly structure of a transformer tester provided in an embodiment of the present invention. Detailed Implementation

[0046] This invention provides a transformer testing device and instrument based on dual DSP chips, which improves the speed and accuracy of transformer data sampling and facilitates the integration of multiple testing functions into one device.

[0047] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0048] Please see Figure 1 , Figure 1 This is a schematic diagram of a transformer testing device based on dual DSP chips, provided as an embodiment of the present invention.

[0049] The first aspect of this embodiment provides a transformer testing device based on dual DSP chips, comprising: a first DSP chip 1, a second DSP chip 2, a high-pass filter module 3, an amplifier circuit 4, a first AD conversion circuit 7, a second AD conversion circuit 8, a first signal acquisition module 5, a second signal acquisition module 6, a logic circuit module 9, a data storage device, and a USB communication interface 11.

[0050] The second DSP chip 2 is connected to the high-pass filter module 3; the high-pass filter module 3 is connected to the amplifier circuit 4;

[0051] The first AD conversion circuit 7 is connected to the first signal acquisition module 5;

[0052] The second AD conversion circuit 8 is connected to the second signal acquisition module 6;

[0053] The second signal acquisition module 6, the first AD conversion circuit 7, and the second AD conversion circuit 8 are respectively connected to the logic circuit module 9;

[0054] The logic circuit module 9, the first AD conversion circuit 7, and the second AD conversion circuit 8 are connected to the data memory;

[0055] The data memory is connected to the first DSP chip 1 via a data address bus;

[0056] The logic circuit module 9 is connected to the first DSP chip 1 via a control bus;

[0057] The first DSP chip 1 is connected to the USB communication interface 11 via a control bus and a data address bus;

[0058] The first DSP chip 1 is used to generate a square wave with a preset frequency multiplication factor;

[0059] The second DSP chip 2 is used to generate a sine wave signal at a preset frequency.

[0060] It should be noted that in this embodiment, the second DSP chip 2 is used as a waveform processing DSP chip to generate sine wave signals at preset frequency points. In this embodiment, it is specifically used to generate sine wave signals with a frequency range of 1kHz to 1MHz and a step size of 1kHz, totaling 1000 frequency points.

[0061] The sinusoidal signal generated by the second DSP chip 2 is filtered by a high-pass filter module and an amplifier circuit to reduce DC interference. After the filtered sinusoidal signal is subjected to a Fourier transform, a signal with an amplitude of +5V is obtained as an excitation signal. This excitation signal is used to output and act on the transformer under test during testing.

[0062] The first signal acquisition module 5 is used to acquire standard input signals. The standard input signal refers to the standard response signal corresponding to the excitation signal. It is used as a benchmark for judging whether the transformer parameter characteristics are normal or not. It can be understood as a standard reference value.

[0063] It is understandable that when the second DSP chip 2 generates the excitation signal, it simultaneously outputs a standard response signal corresponding to the excitation signal to the first signal acquisition module 5.

[0064] The second signal acquisition module 6 is used to acquire the response input signal. The response input signal refers to the actual response signal fed back by the transformer under test under the action of the excitation signal.

[0065] The first AD conversion circuit 7 is used to receive the standard input signal from the first signal acquisition module 5, perform analog-to-digital conversion on the standard input signal, and transmit the standard digital signal obtained after analog-to-digital conversion to the data memory according to the timing instructions output by the logic circuit module.

[0066] The second AD conversion circuit 8 is used to receive the response input signal from the second signal acquisition module, and to perform analog-to-digital conversion on the standard input signal. According to the timing instructions output by the logic circuit module, the standard digital signal obtained after analog-to-digital conversion is transmitted to the data memory according to the timing relationship.

[0067] The logic circuit module 9 is used to receive control instructions sent by the first DSP chip 1, and output corresponding timing instructions to the first AD conversion circuit 7 and the second AD conversion circuit 8 according to the control instructions, so as to control the first AD conversion circuit 7 and the second AD conversion circuit 8 to transmit the corresponding timing standard input signals and response input signals to the data memory.

[0068] The first DSP chip 1 is used to output control instructions to the logic circuit module, and also to generate a square wave with a preset frequency multiplication. It samples the signal from the data memory according to the square wave with the preset frequency multiplication, processes the sampled signal, and outputs the processed result through the USB communication interface 11.

[0069] Signal processing refers to the processing of standard input signals and response signals, performing waveform analysis to obtain the analytical results of the characteristic parameters of the transformer under test. The first DSP chip 1 can output the analyzed waveform results to a PC or other cloud platforms via a USB communication interface.

[0070] As an example, the first DSP chip 1 generates a square wave with a frequency multiplied by 32, thereby ensuring that the signal sampling rate is 32 times that of the measured signal, so that there can be 32 sampling points in each sampling period, thus controlling the signal acquisition rate.

[0071] This embodiment discloses a transformer testing device based on dual DSP chips, including a first DSP chip 1, a second DSP chip 2, a high-pass filter module 3, an amplifier circuit 4, a first AD conversion circuit 7, a second AD conversion circuit 8, a first signal acquisition module 5, a second signal acquisition module 6, a logic circuit module 9, a data storage device 10, and a USB communication interface 11. In this embodiment, the second DSP chip 2 generates an excitation signal for output, which is used to test the parameter characteristics of the transformer under test. The second DSP chip 2 also generates a standard input signal corresponding to the excitation signal and sends it to the first signal acquisition module 5. The second signal acquisition module 6 receives the response input signal fed back by the transformer under test under the action of the excitation signal. The first DSP chip 1 outputs control instructions to the logic circuit module. The logic circuit module outputs timing instructions to the first AD conversion circuit 7 and the second AD conversion circuit 8 according to the received control instructions. The first AD conversion circuit 7 and the second AD conversion circuit 8 transmit the standard input signal and the response input signal to the data memory according to the timing relationship. The first DSP chip 1 generates a square wave with a preset frequency multiplication and acquires the standard input signal data and response input signal data in the data memory according to the square wave. This achieves high-speed sampling of the test data and avoids data overlap, which affects data accuracy. The first DSP chip 1 analyzes the transformer characteristic parameters based on the standard input signal data and the response input signal data, and outputs the obtained transformer characteristic parameter results through the USB communication interface 11 to realize the testing of the transformer characteristic parameters.

[0072] In this embodiment, a sinusoidal signal at a preset frequency is generated by the second DSP chip 2 as the excitation signal, and a square wave with a preset multiplier is generated by the first DSP chip 1. The signal is sampled from the data memory according to the square wave with the preset multiplier, thus realizing a dual DSP design. This improves the existing single DSP chip design. Furthermore, through the structure and data interaction of the first DSP chip 1, the logic circuit module, and the data memory, high-speed sampling is achieved, and data overlap is avoided, which affects data accuracy. At the same time, the cost of integration is reduced, and the practical application value is improved.

[0073] Please see Figure 2 , Figure 2 This is a schematic diagram of the structure of a transformer tester provided in an embodiment of the present invention.

[0074] The second aspect of this embodiment provides a transformer tester, wherein the tester includes: a central control module 205, a DC resistance test module 201, an AC resistance test module 202, a transformer turns ratio test module 203, an AC parameter test module 204, and a central control module 205.

[0075] The DC resistance testing module 201, the AC resistance testing module 202, the transformer turns ratio testing module 203, and the AC parameter testing module 204 are connected to the central control module 205 via an RS485 bus.

[0076] The DC resistance test module 201, the AC resistance test module 202, the transformer turns ratio test module 203, and the AC parameter test module 204 are respectively integrated by the test device provided in the first aspect of this embodiment.

[0077] In this embodiment, the transformer testing device based on a dual-DSP chip is integrated to obtain a DC resistance testing module 201, an AC resistance testing module 202, a transformer turns ratio testing module 203, and an AC parameter testing module 204. Each testing module is integrated into a separate testing device. Therefore, by using the integrated testing modules based on the dual-DSP chip transformer testing device, each testing module possesses high-speed data sampling capabilities and independent data processing functions. Furthermore, integrating these testing modules into the testing instrument achieves the integration and unification of multiple different testing functions, improving the testing efficiency of transformers. It also avoids the problem in existing transformer testing where multiple dedicated instruments are required to test a single test item, providing a more portable testing instrument with multiple testing functions. Furthermore, in this embodiment, each test module transmits test data to the central control module 205 via an RS485 bus. The central control module 205 manages the test data obtained by each test module, avoiding the problem in existing transformer testing where different test instruments may come from different manufacturers and the test data from multiple test instruments are not completely compatible, causing inconvenience in data management after the test. At the same time, it avoids the problem of testers needing to master the use of multiple instruments, resulting in a high learning cost.

[0078] Understandably, each test module can be used independently or connected to the computer 501. The host computer can connect to each functional module simultaneously to form a comprehensive electrical equipment testing system. The host computer 501 can operate each functional module and also perform display and printing functions.

[0079] In one specific embodiment, the tester further includes a constant current source; the constant current source is connected to the DC resistance test module 201, the AC resistance test module 202, the transformer turns ratio test module 203 and the AC parameter test module 204 respectively.

[0080] It should be noted that the constant current source is used to provide a stable current input for the DC test module, and the DC resistance test module 201 uses high-current flow-controlled power supply technology to test DC resistance parameters.

[0081] In one specific embodiment, the AC resistance testing module 202 is used to test the insulation resistance parameters of the transformer under test. The transformer turns ratio testing module 203 is used to test the turns ratio parameters of the transformer. The AC parameter testing module 204 is used to test the loss parameters and power frequency withstand voltage parameters of the transformer under test. The DC testing module is used to test the DC resistance parameters of the transformer under test.

[0082] It should be noted that the DC resistance test module 201, AC resistance test module 202, AC parameter test module 204, and transformer turns ratio test module 203 have corresponding test methods pre-written using Visual C++ programming.

[0083] In one specific embodiment, the tester further includes a display screen 301;

[0084] The central control module 205 is connected to the display screen 301.

[0085] In one specific embodiment, the tester further includes a printer 401;

[0086] The central control module 205 is connected to the printer 401.

[0087] In one specific embodiment, the central control module 205 is connected to the computer 501.

[0088] This embodiment provides a transformer tester that can acquire signals at high speed. It integrates multiple testing functions into one instrument, achieving high integration, modular networking, data standardization, small size, and light weight. It has multiple functions such as DC resistance, insulation resistance, no-load loss parameters, turns ratio error testing, and power frequency withstand voltage testing of distribution transformers, providing a more portable testing instrument for the field of transformer testing.

[0089] Please see Figure 3-7 , Figure 3-7 The following diagram illustrates the assembly structure of a transformer tester provided by an embodiment of the present invention.

[0090] The third aspect of this embodiment provides a transformer tester, which includes a rear panel in addition to the contents of the first and third aspects described above.

[0091] See Figure 3 The rear panel includes a DC resistance test port, an insulation resistance test port, a transformer turns ratio test port, an AC parameter test port, and a power frequency withstand voltage test port.

[0092] The DC resistance test ports include: I+ port, I- port, U+ port, and U- port.

[0093] The insulation resistance test ports include: L port, G port, and E port.

[0094] The transformer turns ratio test ports include: high-voltage side three-phase ports A, B, C, O; low-voltage side three-phase ports a, b, c, O.

[0095] The AC parameter test ports include: IA+ port, IB+ port, IC+ port; IA- port, IB- port, IC- port; UA port, UB port, UC port, and UO port.

[0096] The power frequency withstand voltage test ports include: power supply port, instrument port, and output port.

[0097] In practical applications, the transformer under test can be connected to the corresponding port according to the requirements of the test project.

[0098] In one specific embodiment, the rear panel also includes a power interface and a communication interface.

[0099] The power interface is used to connect to an external power source, and the communication interface is used to establish a communication connection with external terminal devices or a host computer to enable data interaction with external devices.

[0100] In one specific embodiment, see Figure 4 The front panel of the transformer tester is equipped with a printer, a monitor, and a USB interface.

[0101] In another preferred embodiment, see Figure 5-6 The V+ port in the DC test module is connected to the I+ port on the rear panel, and the V- port in the DC test module is connected to the AC resistance test module.

[0102] The AC resistance test module provides I+, I-, U+, and U- ports for connecting to the rear panel ports.

[0103] The AC parameter module terminals are respectively connected to the corresponding windings of the transformer, the panel switch AC220V, and the transformer AC220V.

[0104] The transformer turns ratio test module provides a terminal module for connecting the 7.5V winding terminal and the 13V winding terminal of the transformer. During testing, the transformer turns ratio is measured by connecting to the transformer.

[0105] In one specific embodiment, the AC resistance test module is used to connect to the UA and UB terminals, the U0 and UB terminals on the rear panel, and the CT board on the rear panel to measure AC resistance. The CT board refers to the terminals for each current input on the rear panel.

[0106] In another preferred embodiment, the rear panel also includes an 8P aviation socket.

[0107] The upper terminal module of the AC parameter module is connected to the 8P aviation socket, which is used for voltage boosting, voltage bucking, closing, and opening to enable phase-by-phase loss testing and insulation withstand voltage testing.

[0108] The AC parameter module is also used to measure AC losses using an automatic measurement method for Z-type transformers.

[0109] The tester provided in this embodiment can correctly display all electrical parameters under conditions such as third harmonic frequency, and realizes synchronous measurement of all data within the same cycle, automatic waveform distortion correction, temperature correction, dynamic addition and deletion of data tables, and has functions such as data storage, generation of data reports, viewing of data curves, and printing of data curves.

[0110] In another preferred embodiment, the DC resistance test module is connected to the AC parameter test module and the AC resistance test module respectively via wires.

[0111] The AC resistance module is connected to the transformer turns ratio test module via wires.

[0112] In a specific application example, the usage process of a transformer tester provided in this embodiment is as follows:

[0113] S1: Start the tester. On the display screen, click the "Set Serial Port" shortcut button, set the serial port number according to the selected computer communication serial port, set the baud rate according to the communication baud rate set by the tester, and click the "OK" button to complete the settings and save them. After setting the serial port, the program will close the serial port. If you want to perform device testing, please reopen the serial port.

[0114] S2: Click the "Open Serial Port" shortcut button.

[0115] Any device testing operation requires the computer to communicate with the testing instrument via a serial port. Therefore, please ensure that the serial port is open before testing. If the serial port is open normally, the "Open Serial Port" button will be grayed out, and the "Serial Port Status" at the bottom of the window will display "Open".

[0116] S3: Enter the name and / or device number of the device under test.

[0117] To distinguish the device under test and facilitate test data retrieval, please enter or select the name of the device under test before testing. For devices that have already been tested, click the drop-down arrow to directly select the device name. For devices that have not been tested, you can directly enter the device name, and the program will automatically save the device name and related parameters. The device name can contain Chinese characters, numbers, and symbols, with a maximum of 24 Chinese characters. Some tests also require entering the device number, which must be 8 digits or English letters and cannot contain Chinese characters.

[0118] S4: Depending on the testing requirements of different projects, click the drop-down button to select the corresponding test project;

[0119] S5: Enter the relevant parameters of the device under test and click the "Start Test" button to begin the test.

[0120] Before starting the test, please enter the relevant parameters of the device under test. If the parameters are incomplete, the program will provide a corresponding prompt. For detailed parameter descriptions of the device under test, please refer to the instruction manual of the corresponding device.

[0121] S6: When the monitor displays the test results, click the "Save Data" button to save the test results.

[0122] After the test begins, if data communication and instrument status are normal, the test results will be displayed on the monitor or computer. When the data display is stable, you can click the "Save Data" button to save the test results. The program does not save the test results automatically, so if you wish to retain the test results, please be sure to click the "Save Data" button.

[0123] S7: After saving the test results, click the "Stop Test" button to stop the current test item.

[0124] Once the test begins, the test parameters, test items, and other data will not be able to be modified or selected. After the current test item is completed and saved, please click the "Stop Test" button to stop the current test item. At this time, you can continue to test other items.

[0125] S8: When you need to query data, you can click the query button to view past test records on the current page;

[0126] S9: When the tester is not connected to another computer, test records can be exported via USB interface.

[0127] If a computer is not connected to save test records during testing, test records can be exported from the testing instrument using a USB flash drive. This function reads the recorded data from the USB flash drive and displays it on the current page. The currently displayed data can be saved to the computer by clicking the "Save Data" button, or it can be printed.

[0128] S10: When data needs to be printed, select the print function to print.

[0129] It can print the currently displayed test records and export them as Word or Excel files;

[0130] S11: After completing all test items, click the "Exit" button to close the current test instrument screen;

[0131] To exit, click the "Exit" button to close the current test instrument screen.

[0132] In another specific application example, for the "three-wire phase separation" test item, the usage procedure of a transformer tester provided in this embodiment is as follows:

[0133] For the "three-wire phase separation" test, when using the above instrument to perform the three-wire phase separation test, the program will control the instrument to perform the AB, CA, and BC phase tests sequentially. Clicking the "Start Test" button will prompt the program with the following message:

[0134] Measurement of phases AB is in progress. Once the data stabilizes, click the "Next Phase" button to measure phase CA.

[0135] Once the data for phases AB stabilizes, click the "Next Phase" button. Do not turn off the test power. Adjust the wiring to phase CA. The program will then prompt:

[0136] Phase CA is being measured. Once the data stabilizes, click the "Next Phase" button to measure phase BC.

[0137] Once the CA phase data stabilizes, click the "Next Phase" button. Do not turn off the test power. Adjust the wiring to phases BC. The program will then prompt:

[0138] The BC phase is being measured. Once the data stabilizes, click the "Stop Measurement" button to end the measurement.

[0139] Once the BC phase data stabilizes, click the "Stop Measurement" button to end the measurement. After ending the measurement, click the "Save Data" button to save the test results.

[0140] In a specific example, the tester provided in this embodiment mainly has the following technical specifications:

[0141] DC resistance measurement accuracy range: ±0.2%, measurement range: 100μΩ~10kΩ;

[0142] AC parameter measurement accuracy range: voltage, current ±0.2%, power: ±0.5% (cosφ>0.1);

[0143] Transformer ratio measurement accuracy: ±0.1% (0.8~1000), ±0.2% (1000~2000), ±0.5% (2000~5000); Measurement range: 0.8~5000.

[0144] Insulation resistance accuracy: ±10%, measurement range: 0.1~4000;

[0145] Power frequency withstand voltage: 5KVA, accuracy: 0.5%;

[0146] Main unit dimensions: 400×280×200mm; Main unit weight: 12kg.

[0147] As can be seen from the above, compared with the size of existing conventional instruments, the transformer tester provided in this embodiment has more testing functions, while reducing the size and weight, making it easier to carry.

[0148] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0149] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between apparatuses or units through some interfaces, and may be electrical, mechanical, or other forms.

[0150] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0151] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each functional unit can be a separate physical entity, or two or more functional units can be integrated into one processing unit. The integrated unit described above can be implemented in hardware or as a software functional unit.

[0152] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0153] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A transformer testing device based on dual DSP chips, characterized in that, include: First DSP chip, second DSP chip, high-pass filter module, amplifier circuit, first AD conversion circuit, second AD conversion circuit, first signal acquisition module, second signal acquisition module, logic circuit module, data storage, USB communication interface; The second DSP chip is connected to the high-pass filter module; the high-pass filter module is connected to the amplifier circuit. The first AD conversion circuit is connected to the first signal acquisition module; The second AD conversion circuit is connected to the second signal acquisition module; The second signal acquisition module, the first AD conversion circuit, and the second AD conversion circuit are respectively connected to the logic circuit module; The logic circuit module, the first AD conversion circuit, and the second AD conversion circuit are connected to the data memory. The data storage is connected to the first DSP chip via a data address bus; The logic circuit module is connected to the first DSP chip via a control bus; The first DSP chip is connected to the USB communication interface; The second DSP chip is used to generate a sinusoidal signal at a preset frequency point, and inputs the sinusoidal signal into the high-pass filter module and the amplifier circuit in sequence to obtain an excitation signal and a standard response signal corresponding to the excitation signal. The excitation signal is then input to the transformer under test, and the standard response signal is input to the first signal acquisition module. The first AD conversion circuit is used to receive the standard response signal from the first signal acquisition module, and to perform analog-to-digital conversion on the standard response signal. According to the timing instructions output by the logic circuit module, the standard digital signal corresponding to the standard response signal obtained after analog-to-digital conversion is transmitted to the data memory according to the timing relationship. The second signal acquisition module is used to acquire the response input signal; the response input signal is the actual response signal fed back by the transformer under test under the action of the excitation signal; The second AD conversion circuit is used to receive the response input signal from the second signal acquisition module, and to perform analog-to-digital conversion on the response input signal. According to the timing instructions output by the logic circuit module, the standard digital signal corresponding to the response input signal obtained after analog-to-digital conversion is transmitted to the data memory according to the timing relationship. The first DSP chip is used to generate a square wave with a preset frequency multiplication factor, sample the signal from the data memory according to the square wave with the preset frequency multiplication factor, process the sampled signal, and output the processed result through the USB communication interface. It is also used to output control commands to the logic circuit module, so that the logic circuit module outputs corresponding timing commands to the first AD conversion circuit and the second AD conversion circuit according to the control commands.

2. A transformer tester, characterized in that, The tester includes: a central control module, a DC resistance test module, an AC resistance test module, a transformer turns ratio test module, an AC parameter test module, and a central control module; The DC resistance test module, the AC resistance test module, the transformer turns ratio test module, and the AC parameter test module are connected to the central control module via an RS485 bus. The DC resistance test module, the AC resistance test module, the transformer turns ratio test module, and the AC parameter test module are each integrated by the test device as described in claim 1.

3. The testing instrument according to claim 2, characterized in that, The DC resistance test module is used to test the DC resistance parameters of the transformer under test.

4. The testing instrument according to claim 2, characterized in that, The AC resistance test module is used to test the insulation resistance parameters of the transformer under test.

5. The testing instrument according to claim 2, characterized in that, The transformer turns ratio test module is used to test the turns ratio parameters of the transformer.

6. The testing instrument according to claim 2, characterized in that, The AC parameter testing module is used to test the loss parameters and power frequency withstand voltage parameters of the transformer under test.

7. The testing instrument according to claim 2, characterized in that, The tester also includes a constant current source; The constant current source is connected to the DC resistance test module, the AC resistance test module, the transformer turns ratio test module, and the AC parameter test module, respectively.

8. The testing instrument according to claim 2, characterized in that, The tester also includes a display screen; The central control module is connected to the display screen.

9. The testing instrument according to claim 2, characterized in that, The testing instrument also includes a printer; The central control module is connected to the printer.

10. The testing instrument according to claim 2, characterized in that, The central control module is connected to the computer.

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