Calibration system for small signal measuring plate of direct-current control protection device

Abstract

The invention discloses a DC control protection device small signal measurement board calibration system, and the system comprises a management module which is used for transmitting a test instruction to a program control DC source according to the obtained parameter information of a to-be-tested product, and transmitting a sampling instruction to a sampling calibration module; the program control direct current source is used for outputting a test signal to the product to be tested according to the received test instruction; the sampling calibration module is used for sampling an output signal of the to-be-tested product according to the received sampling instruction to obtain a sampling signal; performing data processing on the sampling signal to obtain null shift and gain calibration coefficients of the to-be-tested product; transmitting the null shift and gain calibration coefficient of the to-be-tested product to the to-be-tested product; and null shift and gain calibration coefficients returned after the product to be tested is stored are checked. According to the invention, the independent calibration test of the small signal measuring board of the direct current control protection device is realized, the calibrated small signal measuring board and the DSP sampling board can be randomly paired for use during engineering maintenance, the production and engineering maintenance efficiency is improved, and the manpower and material resource cost is saved.

Description

Technical Field

[0001] The invention belongs to the technical field of automatic testing of a direct current control protection device, and in particular relates to a small signal measurement board calibration system for a direct current control protection device. Background Art

[0002] The small signal measurement board of the DC control protection device is used to collect small signal voltage or current in the DC transmission system, filter, amplify and digitize the collected signals, and transmit the processed data to the main control unit. Through precise signal acquisition and processing, real-time monitoring of signal anomalies, timely detection of faults, avoidance of system instability caused by accumulation of small deviations, and ensure stable operation of the system. Therefore, it is necessary to calibrate the measurement accuracy of the small signal measurement board of the DC control protection device before the whole machine is installed to ensure the accuracy of signal measurement.

[0003] The existing DC control protection device small signal measurement board measurement accuracy calibration method is generally carried out in the whole machine test link. The DC control protection device is manually powered on, and the voltage and current analog quantities are added to the small signal measurement board of the DC control protection device using a DC control protection tester. Then the calibration program is manually executed through the LCD. After the DSP sampling board calibration program is calculated through sampling, the calibrated zero drift and gain coefficient are stored in the specified memory. The problem with this method is that it is necessary to manually control the DC control protection tester to add quantity, operate the LCD menu to execute the calibration items, save the accuracy coefficient, etc., which is inefficient, and there are problems of misoperation and missed operation, and the reliability is not high. At the same time, the small signal measurement board of the DC control protection device and the DSP sampling board are bound together for calibration. When the small signal measurement board measurement accuracy problem is handled on the engineering site, the small signal measurement board and the DSP sampling board must be replaced at the same time, which greatly increases the manpower and material costs. Considering the actual engineering needs and the control hardware cost, the small signal measurement board does not have an AD sampling chip in the hardware design, which brings difficulties to the separate calibration test of the small signal measurement board. Summary of the invention

[0004] In order to solve the deficiencies in the prior art, the present invention provides a small signal measurement board calibration system for a DC control protection device, which realizes independent calibration and testing of the small signal measurement board of the DC control protection device. During engineering maintenance, the calibrated small signal measurement board and the DSP sampling board can be arbitrarily paired for use, thereby improving production and engineering maintenance efficiency and saving manpower and material costs.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a small signal measurement board calibration system of a DC control protection device, comprising: a management module, used to send a test instruction to a programmable DC source according to the acquired parameter information of the product to be tested, and send a sampling instruction to a sampling calibration module; the programmable DC source is used to output a test signal to the product to be tested according to the received test instruction; the sampling calibration module is used to sample the output signal of the product to be tested according to the received sampling instruction to obtain a sampling signal; data processing is performed on the sampling signal to obtain the zero drift and gain calibration coefficients of the product to be tested; the zero drift and gain calibration coefficients of the product to be tested are transmitted to the product to be tested; and the zero drift and gain calibration coefficients transmitted back after being stored by the product to be tested are verified.

[0006] Furthermore, it also includes a barcode scanner for scanning the QR code on the product to be tested and transmitting the code to the management module, so as to obtain parameter information of the product to be tested.

[0007] Furthermore, it also includes a display module that is communicatively connected to the management module, and the display module is used to display the calibration progress and calibration results.

[0008] Furthermore, the management module is respectively connected to the barcode scanner and the programmable DC source via the RS232 serial port, is respectively connected to the display module via the RS485 serial port, and is respectively connected to the product to be tested and the sampling and calibration module via the CAN bus; the product to be tested and the sampling and calibration module are respectively connected to each other via the CAN bus.

[0009] Furthermore, the parameter information of the product to be tested includes a board model, a version number, and a board unique identification code.

[0010] Furthermore, the test signal is a small signal DC voltage or current output by a programmable DC source according to a received test instruction; the output signal of the product to be tested is a DC voltage signal output by the product to be tested after the input small signal DC voltage or current is converted by a circuit.

[0011] Furthermore, data processing is performed on the sampling signal, including: performing linear fitting on the sampling signal using the least square method, and calculating the zero drift and gain calibration coefficients.

[0012] Furthermore, the zero drift and gain calibration coefficients sent back after storage of the product to be tested are checked, including: after the sampling calibration module transmits the zero drift and gain calibration coefficients of the product to be tested to the product to be tested, the product to be tested stores the received zero drift and gain calibration coefficients in a designated memory, and then reads back the stored zero drift and gain calibration coefficients from the designated memory and sends them back to the sampling calibration module; the sampling calibration module checks the zero drift and gain calibration coefficients sent back by the product to be tested with the original calculated data to ensure that the two are consistent.

[0013] Furthermore, the sampling calibration module is configured with a DC control protection device standard sampling board test chip, and the DC control protection device standard sampling board test chip is loaded with a DSP sampling calculation calibration program.

[0014] Furthermore, the management module includes: a power board, a CPU management board and a backplane assembled in the chassis for power supply, wherein the backplane is used for the insertion and connection of the power board, the CPU management board, the product to be tested, the sampling and calibration module and the display module.

[0015] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the management module of the present invention sends a test instruction to the programmable DC source and a sampling instruction to the sampling calibration module according to the acquired parameter information of the product to be tested; the programmable DC source outputs a test signal to the product to be tested according to the received test instruction; the sampling calibration module samples the output signal of the product to be tested according to the received sampling instruction to obtain a sampling signal; data processing is performed on the sampling signal to obtain the zero drift and gain calibration coefficients of the product to be tested; the zero drift and gain calibration coefficients of the product to be tested are transmitted to the product to be tested; the zero drift and gain calibration coefficients transmitted back after storage of the product to be tested are verified; an independent calibration test of the small signal measurement board of the DC control protection device is realized, and the calibrated small signal measurement board and the DSP sampling board can be arbitrarily paired for use during engineering maintenance, thereby improving production and engineering maintenance efficiency and saving manpower and material costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural block diagram of a small signal measurement board calibration system for a DC control protection device provided by an embodiment of the present invention; Figure 2 is a flowchart of the management module performing automatic calibration in an embodiment of the present invention; Figure 3 It is a flowchart of the small signal measurement board module performing calibration in an embodiment of the present invention. DETAILED DESCRIPTION

[0017] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0018] A small signal measurement board calibration system for a DC control protection device, a program-controlled DC source, used to output a test signal to a product under test according to a received test instruction; a sampling calibration module, used to sample the output signal of the product under test according to the received sampling instruction to obtain a sampling signal; data processing the sampling signal to obtain the zero drift and gain calibration coefficients of the product under test; transmitting the zero drift and gain calibration coefficients of the product under test to the product under test; verifying the zero drift and gain calibration coefficients transmitted back after storage of the product under test. A barcode scanner, used to scan the QR code on the product under test and transmit it to the management module, so as to obtain the parameter information of the product under test; a display module connected to the management module for communication, used to display the calibration progress and calibration results.

[0019] like Figure 1 As shown, the program-controlled DC source receives the instruction sent by the management module, and outputs a small-signal DC voltage or current to the small-signal measurement board module (i.e., the product to be tested) of the DC control protection device.

[0020] The barcode scanner scans the QR code on the small signal measurement board module of the DC control protection device and sends the scanned parameter information to the management module.

[0021] After receiving and verifying the parameter information of the small signal measurement board module of the DC control protection device, the management module sends a control message to the program-controlled DC source, and the program-controlled DC source outputs a small signal DC voltage or current to the small signal measurement board module of the DC control protection device.

[0022] The small signal measurement board module of the DC control protection device converts the input small signal DC voltage or current through the circuit to output a DC voltage signal.

[0023] After receiving the sampling instruction sent by the management module, the DC control protection device standard sampling board module (i.e., sampling calibration module) collects the DC voltage signal output by the DC control protection device small signal measurement board module, calculates the zero drift and gain calibration coefficients using the least squares linear fitting method, and then sends the zero drift and gain calibration coefficients to the DC control protection device small signal measurement board through the CAN bus. The DC control protection device small signal measurement board receives and stores it in the specified memory, then reads back the stored data from the specified memory and sends it back to the DC control protection device standard sampling board module. The DC control protection device standard sampling board module compares its original calculated data with the stored data sent back by the DC control protection device small signal measurement board to ensure that the two are consistent.

[0024] The DC control protection device standard sampling board module and the DC control protection device small signal measurement board module send the real-time test progress and test results to the management module through the CAN bus, and the management module controls the LCD display module (i.e., the display module) to display the real-time calibration test progress and calibration test results.

[0025] The management module includes a power board, a CPU management board and a backplane assembled in the chassis for power supply, wherein the backplane is used for the insertion and connection of the power board, the CPU management board, the DC control protection device small signal measurement board module, the DC control protection device standard sampling board module and the LCD display module.

[0026] The management module transmits data with the small signal measurement board module of the DC control protection device and the standard sampling board module of the DC control protection device through the CAN bus.

[0027] The standard sampling board module of the DC control protection device transmits data with the small signal measurement board module of the DC control protection device through the CAN bus.

[0028] The barcode scanner sends parameter information obtained by scanning the QR code on the small signal measurement board module of the DC control protection device to the management module through the RS232 serial port.

[0029] The program-controlled DC source receives instructions sent by the management module through the RS232 serial port.

[0030] The LCD display module transmits data with the management module via the RS485 serial port.

[0031] The parameter information of the small signal measurement board module of the DC control protection device includes the board model, version number, and board unique identification code.

[0032] The DC control protection device standard sampling board module includes a DC control protection device standard sampling board test chip, wherein the DC control protection device standard sampling board test chip is loaded with a DSP sampling calculation calibration program.

[0033] The flowchart of the management module performing automatic calibration in the embodiment of the present invention is as follows: Figure 2 As shown. After the calibration test starts, the CPU management board in the management module configures the complete test items and test process to form a test case text; the tester scans the QR code of the small signal measurement board module of the DC control protection device through a barcode scanner, and the management module receives the QR code information of the small signal measurement board module of the DC control protection device and verifies that it is correct. According to the test process, it powers on to confirm the self-test status of the small signal measurement board module and the standard sampling board module of the DC control protection device, and sends a test instruction to the standard sampling board module of the DC control protection device; and receives and analyzes the test calibration data sent by the standard sampling board module of the DC control protection device, and generates a test report based on the test calibration data.

[0034] The flowchart of the small signal measurement board module of the DC control protection device in the embodiment of the present invention performing calibration is as follows: Figure 3As shown, the small signal measurement board module of the DC control protection device receives the test calibration step instructions sent by the management module, specifically executes the test calibration content included in the test calibration project, and sends the test calibration data to the management module in real time.

[0035] The present invention solves the sampling calculation and data exchange problems existing in the automatic calibration of the small signal measurement board of the DC control protection device, and effectively improves the reliability and efficiency of the calibration of the small signal measurement board of the DC control protection device; realizes the independent calibration test of the small signal measurement board of the DC control protection device, and the calibrated small signal measurement board and the DSP sampling board can be arbitrarily paired for use during engineering maintenance, thereby improving the production and engineering maintenance efficiency and saving manpower and material costs.

[0036] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A small signal measurement board calibration system for a DC control protection device, characterized in that: include: A management module, used to send a test instruction to the program-controlled DC source and a sampling instruction to the sampling and calibration module according to the acquired parameter information of the product to be tested; A program-controlled DC source, used to output a test signal to the product under test according to the received test instruction; A sampling calibration module, used to sample the output signal of the product to be tested according to the received sampling instruction to obtain a sampling signal; Performing data processing on the sampled signal to obtain zero drift and gain calibration coefficients of the product to be tested; Transmit the zero drift and gain calibration coefficients of the product to be tested to the product to be tested; Verify the zero drift and gain calibration coefficients sent back after storage of the product under test.

2. The DC control protection device small signal measurement board calibration system according to claim 1, characterized in that: It also includes a barcode scanner for scanning the QR code on the product to be tested and transmitting the code to the management module to obtain parameter information of the product to be tested.

3. The DC control protection device small signal measurement board calibration system according to claim 2, characterized in that: It also includes a display module that is communicatively connected to the management module, and the display module is used to display the calibration progress and calibration results.

4. The DC control protection device small signal measurement board calibration system according to claim 3, characterized in that: The management module is respectively connected to the barcode scanner and the programmable DC source via the RS232 serial port, is respectively connected to the display module via the RS485 serial port, and is respectively connected to the product to be tested and the sampling and calibration module via the CAN bus; the product to be tested and the sampling and calibration module are connected via the CAN bus.

5. The DC control protection device small signal measurement board calibration system according to claim 1, characterized in that: The parameter information of the product to be tested includes the board model, version number, and board unique identification code.

6. The DC control protection device small signal measurement board calibration system according to claim 1, characterized in that: The test signal is a small signal DC voltage or current output by a programmable DC source according to a received test instruction; the output signal of the product to be tested is a DC voltage signal output by the product to be tested after the input small signal DC voltage or current is converted by a circuit.

7. The DC control protection device small signal measurement board calibration system according to claim 1, characterized in that: The sampling signal is subjected to data processing, including: performing linear fitting on the sampling signal using the least square method, and calculating the zero drift and gain calibration coefficients.

8. The DC control protection device small signal measurement board calibration system according to claim 1, characterized in that: Verifying the zero drift and gain calibration coefficients sent back after storage of the product under test, including: after the sampling calibration module transmits the zero drift and gain calibration coefficients of the product under test to the product under test, the product under test stores the received zero drift and gain calibration coefficients in a designated memory, and then reads back the stored zero drift and gain calibration coefficients from the designated memory and sends them back to the sampling calibration module; the sampling calibration module verifies the zero drift and gain calibration coefficients sent back by the product under test with the original calculated data to ensure that the two are consistent.

9. The DC control protection device small signal measurement board calibration system according to claim 1, characterized in that: The sampling calibration module is configured with a DC control protection device standard sampling board test chip, and the DC control protection device standard sampling board test chip is loaded with a DSP sampling calculation calibration program.

10. The DC control protection device small signal measurement board calibration system according to claim 1, characterized in that: The management module includes: a power board, a CPU management board and a backplane assembled in the chassis for power supply, wherein the backplane is used for inserting and connecting the power board, the CPU management board, the product to be tested, the sampling calibration module and the display module.

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