Portable direct-current voltage transformer fault detection device and method

Abstract

The invention discloses a portable direct-current voltage transformer fault detection device and method, relates to the technical field of direct-current voltage transformer fault detection, and aims to solve the problems that in the prior art, direct-current voltage transformer fault detection needs power-off maintenance, and the detection precision is poor. The portable direct-current voltage transformer fault detection device comprises a main control system, and the main control system adopts an FPGA + ARM dual-processor architecture; the FPGA is connected with a plurality of photoelectric converters and two A / D conversion modules; the FPGA is used for acquiring output voltage digital signal data of the direct-current voltage transformer and transmitting the output voltage digital signal data to the ARM, and the ARM is used for calculating the output voltage digital signal data of the direct-current voltage transformer and judging the fault position of the direct-current voltage transformer. According to the invention, power-off maintenance is not needed, and online segmented detection and judgment are realized so as to complete rapid troubleshooting of faults.

Description

Technical Field

[0001] The invention relates to a portable DC voltage transformer fault detection device and method, belonging to the technical field of DC voltage transformer fault detection. Background Art

[0002] DC transformer is an important primary equipment in the construction and operation of DC transmission system. It provides accurate and reliable measurement information for DC control and protection system. Its operation reliability and measurement accuracy are directly related to the safe and stable operation of DC transmission system.

[0003] At present, China has mastered the core technologies of design, testing, commissioning and production of complete sets of DC transmission equipment, but the research on DC electronic transformers is still relatively backward. Compared with DC transmission equipment, the nationalization process of DC electronic transformers is still relatively slow. There is a lack of corresponding product development experience and fault detection methods, and it is impossible to find the abnormal causes and abnormal points of DC electronic transformers through field tests. In particular, the localization rate of DC voltage transformers is still relatively low. The primary part is still mainly based on Snivent's DC voltage divider, and the secondary part has basically been localized in order to cooperate with control and protection. This distribution of functions has brought great trouble to field testing and fault detection. In recent years, the phenomenon of DC voltage reduction during operation has occurred many times in various converter stations, which has seriously affected the operation safety of the converter stations.

[0004] At present, UHV DC voltage transformers are basically composed of three parts: primary voltage divider, secondary voltage divider, and digital sampling system. The primary voltage divider adopts the principle of resistor-capacitor voltage division, and is composed of a high-voltage arm and a low-voltage arm. The high-voltage arm is composed of a multi-stage resistor-capacitor parallel voltage division circuit in series, and the voltage level is determined by the number of resistor-capacitor circuits in series. Figure 1 R1 and C1 are the equivalent resistance and capacitance of the entire high-voltage arm. In order to obtain good transfer characteristics, the resistors and capacitors in the entire voltage divider circuit are connected in parallel to sample the same time constant. The low-voltage arm is composed of a sampling resistor Rs and a sampling capacitor Cs in parallel. In order to prevent the impact voltage from causing harm to the rear secondary circuit, a TVS voltage regulator is generally connected in parallel to the low-voltage arm to limit the secondary output overvoltage.

[0005] The secondary voltage divider of the DC voltage transformer is composed of multiple pure resistors in parallel, which divide the secondary voltage output by the primary voltage divider into a small voltage signal that can be collected by the digital sampling system. The number of voltage divider circuits is determined by the application requirements of the secondary equipment on site. Since the secondary voltage divider circuit is connected in parallel to the low-voltage arm of the primary voltage divider, the resistance value of the low-voltage arm of the primary voltage divider circuit is changed. In order to ensure the consistency of its AC and DC voltage division, a pre-balancing capacitor Ch is connected in parallel to the secondary voltage divider circuit to balance the resistance value of the secondary voltage divider.

[0006] The digital sampling system of DC voltage transformer consists of remote module and merging unit. The remote module is installed on site, and the small voltage signal output by the secondary voltage divider is converted into a digital signal after conditioning and sampling. The output of the remote module is a serial digital optical signal. The merging unit receives and processes the data sent by multiple acquisition units, and outputs the measured data according to the specified protocol for use by the secondary equipment.

[0007] At present, most of the DC voltage transformers in China use Snivent's DC voltage divider. In the localization transformation, domestic field data acquisition is used to achieve impedance matching and accuracy matching between the voltage divider and the remote module. Therefore, a differential amplifier will be configured between the secondary voltage divider and the remote module. The differential amplifier is used to increase the input impedance of the remote module, while avoiding the influence of the input impedance of the remote module on the voltage divider resistance of the secondary voltage divider. In order to solve the output accuracy problem in the secondary voltage division process, an adjustable resistor will be used in the differential amplifier to fine-tune its output voltage to ensure the overall output accuracy of the DC voltage transformer.

[0008] According to the analysis of DC voltage transformers, during the operation of DC voltage transformers, the DC voltage divider has a relatively low probability of failure, the resistance has the best stability, and the failure rate can be basically ignored, but the capacitance will have some changes. Therefore, for DC voltage transformers, its failures are mainly concentrated in the differential amplifier, remote module, and optical fiber loop.

[0009] The existing DC voltage transformer test method is an offline test method that requires power outage for maintenance, which undoubtedly increases the operating risk of the DC transmission system. In addition, the test object is the overall accuracy of the DC voltage transformer. The accuracy error problem can be found but it is impossible to make a fixed-point judgment on the accuracy error. At the same time, if the DC voltage transformer has a communication failure, the test cannot be completed. The test requires a DC voltage source and a DC transformer tester. These devices are not only bulky, but also require an external power supply, which makes on-site testing inconvenient and costly. Summary of the invention

[0010] The purpose of the present invention is to overcome the deficiencies in the prior art and to provide a portable DC voltage transformer fault detection device and method, which can realize online segmented detection and judgment to quickly troubleshoot faults without power outage for maintenance.

[0011] To achieve the above object, the present invention is implemented by adopting the following technical solutions: In one aspect, the present invention provides a portable DC voltage transformer fault detection device, wherein the DC voltage transformer comprises a DC voltage divider, a differential amplifier, a remote module and a merging unit connected in sequence, wherein the DC voltage divider comprises a primary voltage divider and a secondary voltage divider; The detection device includes a main control system, and the main control system adopts an FPGA+ARM dual processor architecture; The FPGA is connected to a plurality of photoelectric converters and two A / D conversion modules, each of the photoelectric converters is connected to an optical fiber serial port, the optical fiber serial port is used to collect optical signals in the communication link of the DC voltage transformer, and the photoelectric converter is used to convert the optical signals into output voltage digital quantity signal data and transmit them to the FPGA; The A / D conversion module is used to collect the voltage signal and the optical fiber serial digital signal in the communication link of the DC voltage transformer, and convert them into output voltage digital quantity signal data, and transmit them to the FPGA; The FPGA is used to receive the output voltage digital signal data of the DC voltage transformer and transmit it to the ARM, and the ARM is used to judge the fault position of the DC voltage transformer after processing the output voltage digital signal data of the DC voltage transformer.

[0012] Optionally, the main control system is also connected to a high temperature constant temperature crystal oscillator, and the high temperature constant temperature crystal oscillator is used as a system clock to control the data synchronization of each communication link.

[0013] Optionally, the A / D conversion module is connected to the FPGA via an SPI bus, and the A / D conversion module includes a digital-to-analog converter, an internal conversion clock and a multi-function serial interface.

[0014] Optionally, the photoelectric converter includes a fiber optic receiver, and the fiber optic receiver is connected to the fiber optic serial port, the current signal acquisition module and the FPGA; The optical fiber receiver is used to receive the optical signal collected by the optical fiber serial port, and converts the optical signal into a TTL level signal for transmission to the FPGA in one way, and converts the optical signal into a current signal for transmission to the current signal acquisition module in another way. The current signal acquisition module includes a resistor and an A / D chip connected in sequence. The resistor is used to convert the current signal into a voltage signal for transmission to the A / D chip. The A / D chip is connected to the FPGA, and the A / D chip is used to convert the voltage signal into an output voltage digital signal data for transmission to the FPGA.

[0015] Optionally, the ARM is connected to the FPGA via an on-chip bus, the ARM is connected to an Ethernet PHY chip and a control panel, the control panel is used for human-computer interaction, the Ethernet PHY chip is connected to an RJ45 debugging interface, and the Ethernet PHY chip and the RJ45 debugging interface cooperate to download and debug programs; The main control system is also connected to a rechargeable battery, and the rechargeable battery is used to supply power to the main control system.

[0016] On the other hand, the present invention further provides a portable DC voltage transformer fault detection method, which is implemented by the portable DC voltage transformer fault detection device described in any one of the above items, and comprises: The optical fiber serial ports are respectively connected to the spare optical fiber serial ports of the corresponding merging units, and the communication link to which the fault belongs is judged to obtain the judgment result of the faulty communication link; Select an optical fiber serial port to connect to the input end of the merging unit in the faulty communication link, detect the optical fiber loop and optical fiber signal in the faulty communication link, and obtain the inspection result of the faulty communication link; According to the inspection result of the faulty communication link, the A / D conversion module is connected to the output ends of the secondary voltage divider and the differential amplifier respectively, and an optical fiber serial port is selected to be connected to the output end of the remote module in the faulty communication link, and the fault position in the faulty communication link is judged to obtain the fault position judgment result in the faulty communication link.

[0017] Further, the fiber optic serial ports are connected to the spare fiber optic serial ports of the corresponding merging units, and the communication link to which the fault belongs is judged to obtain the fault communication link judgment result, including: Connect the optical fiber serial ports to the spare optical fiber serial ports of the corresponding merging units, collect the optical signals of each communication link, and convert them into digital signal data; Processing the digital signal data of each communication link to obtain synchronous DC voltage amplitude data of each communication link; Compare the synchronous DC voltage amplitude data of each communication link with the actual line voltage. If the synchronous DC voltage amplitude data of all communication links are abnormal to the actual line voltage, it is determined that the DC voltage divider is faulty. If the synchronous DC voltage amplitude data of all communication links are consistent with the actual line voltage, the difference between the synchronous DC voltage amplitude data of each communication link is calculated, and the difference is compared with the preset accuracy error. If the difference is less than the preset accuracy error, it is judged that the DC voltage transformer is not faulty. If the difference of one of the communication links is higher than the preset accuracy error, it is judged that the communication link is faulty.

[0018] Further, the selecting of an optical fiber serial port to be connected to the input end of the merging unit in the faulty communication link, detecting the optical fiber loop and the optical fiber signal in the faulty communication link, and obtaining the faulty communication link inspection result includes: Select an optical fiber serial port to connect to the input end of the merging unit in the faulty communication link, collect the optical signal, and convert it into digital signal data; Optical power detection is performed based on the digital signal data. If the optical power is lower than the preset value, the optical fiber serial port is connected to the output end of the remote module in the faulty communication link to detect the optical power of the remote module. If the optical powers of the input end of the merging unit and the output end of the remote module are both lower than the preset range, it is determined that there is a fault in the remote module; if the optical power of the input end of the merging unit is lower than the preset range, and the optical power of the remote module is higher than the preset range, it is determined that there is a fault in the optical fiber between the remote module and the merging unit.

[0019] Further, according to the inspection result of the faulty communication link, the A / D conversion module is connected to the output ends of the secondary voltage divider and the differential amplifier respectively, and an optical fiber serial port is selected to be connected to the output end of the remote module in the faulty communication link, and the fault position in the faulty communication link is judged to obtain the fault position judgment result in the faulty communication link, including: When the optical power of the remote module in the optical fiber loop and the optical fiber signal detection result in the faulty communication link is within a preset range, the A / D conversion module is connected to the output ends of the secondary voltage divider and the differential amplifier respectively, and an optical fiber serial port is connected to the output end of the remote module in the faulty communication link, and the voltage signal data of the output ends of the secondary voltage divider and the differential amplifier and the optical fiber serial digital signal data of the output end of the remote module are respectively collected and converted into digital quantity signal data respectively; Processing the digital signal data of the secondary voltage divider, the output end of the differential amplifier and the output end of the remote module to obtain the synchronous DC voltage amplitude data of the secondary voltage divider, the output end of the differential amplifier and the output end of the remote module; Taking the synchronous DC voltage amplitude data at the output end of the secondary voltage divider as a reference, the synchronous DC voltage amplitude data at the output end of the differential amplifier and the output end of the remote module are compared with the synchronous DC voltage amplitude data at the output end of the secondary voltage divider. If there are errors in the synchronous DC voltage amplitude data at the output end of the differential amplifier and the output end of the remote module and the errors are consistent, it is determined that the differential amplifier is faulty. If there is no error in the synchronous DC voltage amplitude data at the output end of the differential amplifier and there is an error in the synchronous DC voltage amplitude data at the output end of the remote module, it is determined that the remote module is faulty. If there is no error in the synchronous DC voltage amplitude data at the output end of the differential amplifier and the output end of the remote module, it is determined that the secondary voltage divider is faulty.

[0020] Furthermore, the data processing includes: Extract digital signal data in a 200ms time window; The digital signal data is calculated using generalized polynomial fitting to obtain the DC voltage amplitude data; The interrupt signal generated by the high constant temperature crystal oscillator is used through FPGA to interrupt the A / D conversion module and the acquisition of the optical fiber serial port, and the digital signal data is time-stamped through the interrupt control; The digital signal data is subjected to a secondary linear interpolation calculation according to the time scale to obtain the synchronous DC voltage amplitude data.

[0021] Compared with the prior art, the present invention has the following beneficial effects: The DC voltage transformer fault detection device provided by the present invention adopts a dual-core CPU, realizes the miniaturization and portability of the device, reduces the risk of DC system failure shutdown due to DC voltage transformer fault inspection, and can realize segmented detection to quickly troubleshoot the fault, which is convenient and quick to use; The entire detection process of the DC voltage transformer fault detection method provided by the present invention adopts an online detection method, which does not require power outage for maintenance, and achieves high detection accuracy and rapid troubleshooting of fault points. The present invention adopts a high constant temperature crystal oscillator as the main frequency of the detection device, and then adopts the hardware precise frequency division of FPGA as the sampling clock of the A / D sampling loop, and simultaneously obtains the precise time of the digital sampling moment to ensure the clock accuracy of the entire system and reduce the influence of time error on the detection error; generalized polynomial fitting is used to calculate the amplitude of the DC component, eliminating the influence of harmonic signal machine noise and the like. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of an existing portable DC voltage transformer fault detection device; Figure 2 It is a structural schematic diagram of a portable DC voltage transformer fault detection device in an embodiment of the present invention; Figure 3 A schematic diagram of the structure of a photoelectric converter of a portable DC voltage transformer fault detection device in an embodiment of the present invention; Figure 4 A schematic diagram of a flow chart of a portable DC voltage transformer fault detection method in an embodiment of the present invention; Figure 5 A schematic diagram of multi-port serial optical fiber data synchronization self-calibration wiring of a portable DC voltage transformer fault detection method in an embodiment of the present invention; Figure 6 The present invention is a schematic diagram of the remote module accuracy online self-test wiring of a portable DC voltage transformer fault detection method in an embodiment of the present invention. DETAILED DESCRIPTION

[0023] 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. Example 1

[0024] The embodiment of the present invention provides a portable DC voltage transformer fault detection device. The structure of the DC voltage transformer to be tested is as follows: Figure 1 As shown, it consists of three parts: a primary voltage divider, a secondary voltage divider, and a digital sampling system. The digital sampling system includes a differential amplifier (i.e., an isolation amplifier), a remote module, and multiple merging units.

[0025] like Figure 2 As shown, the main control system of the portable DC voltage transformer fault detection device adopts a dual-core CPU, which is composed of FPGA+ARM dual cores. FPGA and ARM are connected through an on-chip bus. FPGA is responsible for external data collection and data transmission due to its good real-time characteristics, and the ARM core is responsible for data calculation, data generation, human-computer interaction, and program downloading and debugging. In this embodiment, the main control system adopts Xilinx's ZYNQ 7020 chip.

[0026] The FPGA is connected to multiple photoelectric converters and two A / D conversion modules, wherein the photoelectric converter is connected to the FPGA via an I / O interface, and the photoelectric converters are all connected to a fiber optic serial port. In this embodiment, the fiber optic serial port adopts an ST interface, which can be connected to the spare fiber optic serial port of the merging unit of the DC voltage transformer to be tested or the output end of the remote module through the fiber optic serial port, which is used to collect optical signals.

[0027] Since the DC voltage transformer is basically configured on site in a 4-master N-standby mode, 4 merging units are generally configured to correspond to 3 control and protection units and 1 resonance monitoring unit, with a total of 4 communication links, so the number of optoelectronic converters in this embodiment is 4.

[0028] The internal structure of the photoelectric converter is as follows Figure 3 As shown, it specifically includes an optical fiber receiver. In this embodiment, the optical fiber receiver adopts Avago's AFBR-2418TZ, with an operating temperature of -40~85°C, a receiving data wavelength of 865nm, a maximum receiving data rate of 50MBd, and good data compatibility. The optical fiber receiver can convert the optical signal collected by the receiving optical fiber serial port into a TTL level signal output, which is received and analyzed by the FPGA.

[0029] At the same time, the optical fiber receiver converts the optical signal into a current signal output (RSSI) during the photoelectric conversion to detect the intensity of the received optical signal. The larger the output current, the stronger the optical power. One current signal output is connected to a current signal acquisition module, including a resistor and an A / D chip connected in sequence. The current signal is sampled by the resistor R and converted into a voltage signal to be collected by the A / D chip. The A / D chip then converts the collected voltage signal into a digital signal and transmits it to the FPGA. After calculation and processing by the main control system, the optical power can be detected. Among them, the recommended value of the resistor R is 2k, and the resistor R is also connected in parallel with the capacitor C, which acts as a filter.

[0030] The A / D conversion module is connected to the FPGA via the SPI bus. The two A / D conversion modules are respectively used to connect the secondary voltage divider of the DC voltage transformer and the output end of the differential amplifier. The A / D conversion module is used to collect voltage signals and optical fiber serial digital signals to realize voltage difference sampling.

[0031] In this embodiment, the A / D conversion module uses an 18-bit successive approximation analog-to-digital converter A / D7982 with a maximum sampling rate of 1000kSPS, which can achieve high-precision, high-sampling-rate analog-to-digital conversion functions. The A / D7982 is powered by a single 2.5V power supply and includes a low-power, high-speed, 18-bit non-missing-code sampling A / DC (digital-to-analog converter), an internal conversion clock, and a multi-function serial interface port. The reference voltage is provided externally and can be set to the power supply voltage. The power consumption and throughput rate of the A / D conversion module vary linearly. It supports SPI communication mode and daisy chain connection mode, and provides an optional busy indication.

[0032] ARM is connected to a control panel through an off-chip bus. The control panel is used to realize human-computer interaction and is connected to an Ethernet PHY chip through an MII interface. The Ethernet PHY chip is connected to an RJ45 debugging interface to realize program downloading and debugging.

[0033] The main control system is also connected to a rechargeable battery and a high constant temperature crystal oscillator. The rechargeable battery capacity can reach 11200mA and can be used for 24 hours on a single charge, making it portable. The high constant temperature crystal oscillator can be used as the clock of the entire system with a frequency accuracy level of up to 5ppm. Example 2

[0034] like Figure 4 As shown, this embodiment provides a portable DC voltage transformer fault detection method, which is implemented based on the portable DC voltage transformer fault detection device of embodiment 1, and includes the following steps: Step 1: Multi-fiber serial port data synchronization self-calibration Combination Figure 5, connect the optical fiber serial port to the spare optical fiber serial port of the corresponding merging unit, collect the optical signals of each communication link, and convert them into digital signal data.

[0035] The digital signal data of each communication link is processed to obtain the synchronous DC voltage amplitude data of each communication link. The specific operations of the data processing include: Since there are a large number of high-frequency signals in the DC transmission system, the 200ms time window data is extracted when calculating the DC component, and the DC voltage amplitude data is obtained by generalized polynomial fitting to eliminate the influence of harmonic signals and noise.

[0036] The expression of the polynomial function of generalized polynomial fitting is: ; ; in, Indicates i DC voltage amplitude data, m represents the order of accuracy, represents the polynomial coefficients, N represents the number of intermediate variables, Indicates i An intermediate variable, Represents weight.

[0037] Since the voltage signal fluctuates during normal operation and there are synchronization errors between data at different times, the test equipment needs to process the signal synchronously. FPGA uses hardware decoding, and since the optical fiber length is only a few meters to tens of meters, the optical fiber transmission delay error between all multiple communication links can be ignored, that is, the arrival time is considered to be the departure time of the merged unit data. Therefore, after receiving the message, the arrival time of the message header is marked according to the absolute time of the high constant temperature crystal oscillator, and then decoded and calculated by quadratic linear interpolation to obtain the synchronous DC voltage amplitude data of each communication link, thereby realizing data synchronization of each communication link.

[0038] Then, the DC voltage amplitude data of the four communication links at the same time are compared with the actual line voltage. If the synchronous DC voltage amplitude data of all communication links are abnormal from the actual line voltage, it is judged that there is a fault in the DC voltage divider. At this time, the only option is to wait for power outage and maintenance to replace the DC voltage divider.

[0039] If the synchronous DC voltage amplitude data of all communication links conform to the actual voltage of the line, the difference between the synchronous DC voltage amplitude data of each communication link is calculated, and the difference is compared with the preset precision error. If the differences are all less than the preset precision error, it is judged that the DC voltage transformer is not faulty. If the difference of one of the communication links is higher than the preset precision error, it is judged that the communication link is faulty (without considering the possibility of multiple communication links being faulty at the same time).

[0040] Step 2: Check a single communication link The optical fiber loop and the optical fiber signal in the faulty communication link determined in step 1 are checked.

[0041] Connect a fiber optic serial port to the input end of the merging unit in the faulty communication link, collect the optical signal, and convert it into digital signal data. Perform optical power detection on the digital signal data, then connect the fiber optic serial port to the output end of the remote module in the faulty communication link to detect the optical power of the remote module. If the optical powers of the merging unit input end and the remote module output end are both lower than the preset range, it is determined that the optical transmitter of the remote module is faulty and the remote module needs to be replaced. If the optical power of the merging unit input end is lower than the preset range, while the optical power of the remote module output end is higher than the preset range, it is determined that the optical fiber between the remote module and the first merging unit is faulty and the optical fiber needs to be replaced.

[0042] Step 3: Online accuracy detection of remote modules like Figure 6 As shown, if the optical power at the output end of the remote module is within a preset range, the A / D conversion module is connected to the output ends of the secondary voltage divider and the differential amplifier respectively, and the optical fiber serial port is kept connected to the output end of the remote module in the faulty communication link, and the voltage signal data at the output ends of the secondary voltage divider and the differential amplifier and the optical fiber serial digital signal data are respectively collected and converted into digital signal data respectively.

[0043] The digital signal data of the output end of the secondary voltage divider, the differential amplifier and the output end of the remote module are processed to obtain the synchronous DC voltage amplitude data of the output end of the secondary voltage divider, the differential amplifier and the output end of the remote module. The data processing steps are the same as step one.

[0044] Taking the synchronous DC voltage amplitude data at the output of the secondary voltage divider as a reference, the synchronous DC voltage amplitude data at the output of the differential amplifier and the output of the remote module are compared with the synchronous DC voltage amplitude data at the output of the secondary voltage divider: If the synchronous DC voltage amplitude data at the output of the differential amplifier and the output of the remote module have errors and the errors are consistent, it is determined that the differential amplifier is faulty. At this time, it can be determined whether to adjust the adjustable resistor in the differential amplifier or replace the differential amplifier to complete the troubleshooting according to the error size. If the synchronous DC voltage amplitude data at the output of the differential amplifier does not have an error, and the synchronous DC voltage amplitude data at the output of the remote module has an error, it is determined that the remote module is faulty and the remote module can be replaced; if the synchronous DC voltage amplitude data at the output of the differential amplifier and the output of the remote module do not have an error, it is determined that the secondary voltage divider is faulty.

[0045] It should be noted that, in addition to replacing the connection position of the optical fiber interface, the detection method in this embodiment, data processing and judgment are all automatically completed by ARM, and finally the detection results are output to the control panel for the staff to view.

[0046] 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 portable DC voltage transformer fault detection device, wherein the DC voltage transformer comprises a DC voltage divider, a differential amplifier, a remote module and a plurality of merging units connected in sequence, wherein the DC voltage divider comprises a primary voltage divider and a secondary voltage divider, and wherein: It includes a main control system, which adopts FPGA+ARM dual processor architecture; The FPGA is connected to a plurality of photoelectric converters and two A / D conversion modules, each of the photoelectric converters is connected to a fiber optic serial port, the fiber optic serial port is used to collect optical signals in the communication link of the DC voltage transformer, the photoelectric converter is used to convert the optical signals into output voltage digital quantity signal data, and transmit the data to the FPGA; the A / D conversion module is used to collect voltage signals and optical fiber serial digital signals in the communication link of the DC voltage transformer, and convert the signals into output voltage digital quantity signal data, and transmit the data to the FPGA; The FPGA is used to receive the output voltage digital signal data of the DC voltage transformer and transmit it to the ARM, and the ARM is used to judge the fault position of the DC voltage transformer after processing the output voltage digital signal data of the DC voltage transformer.

2. The portable DC voltage transformer fault detection device according to claim 1, characterized in that: The main control system is also connected to a high temperature constant temperature crystal oscillator, which is used as a system clock to control the data synchronization of each communication link.

3. The portable DC voltage transformer fault detection device according to claim 1, characterized in that: The A / D conversion module is connected to the FPGA via an SPI bus, and the A / D conversion module includes a digital-to-analog converter, an internal conversion clock and a multifunctional serial interface.

4. The portable DC voltage transformer fault detection device according to claim 1, characterized in that: The photoelectric converter includes a fiber optic receiver, and the fiber optic receiver is connected to the fiber optic serial port, the current signal acquisition module and the FPGA; The optical fiber receiver is used to receive the optical signal collected by the optical fiber serial port, and converts the optical signal into a TTL level signal for transmission to the FPGA in one way, and converts the optical signal into a current signal for transmission to the current signal acquisition module in another way. The current signal acquisition module includes a resistor and an A / D chip connected in sequence. The resistor is used to convert the current signal into a voltage signal for transmission to the A / D chip. The A / D chip is connected to the FPGA, and the A / D chip is used to convert the voltage signal into an output voltage digital signal data for transmission to the FPGA.

5. The portable DC voltage transformer fault detection device according to claim 1, characterized in that: The ARM is connected to the FPGA via an on-chip bus, the ARM is connected to an Ethernet PHY chip and a control panel, the control panel is used for human-computer interaction, the Ethernet PHY chip is connected to an RJ45 debugging interface, and the Ethernet PHY chip and the RJ45 debugging interface cooperate to download and debug programs; The main control system is also connected to a rechargeable battery, and the rechargeable battery is used to supply power to the main control system.

6. A portable DC voltage transformer fault detection method, characterized in that: The detection method is implemented by the portable DC voltage transformer fault detection device according to any one of claims 1 to 5, which comprises: The optical fiber serial ports are respectively connected to the spare optical fiber serial ports of the corresponding merging units, and the communication link to which the fault belongs is judged to obtain the judgment result of the faulty communication link; Select an optical fiber serial port to connect to the input end of the merging unit in the faulty communication link, detect the optical fiber loop and optical fiber signal in the faulty communication link, and obtain the inspection result of the faulty communication link; According to the inspection result of the faulty communication link, the A / D conversion module is connected to the output ends of the secondary voltage divider and the differential amplifier respectively, and an optical fiber serial port is selected to be connected to the output end of the remote module in the faulty communication link, and the fault position in the faulty communication link is judged to obtain the fault position judgment result in the faulty communication link.

7. The portable DC voltage transformer fault detection method according to claim 6, characterized in that: The method of connecting the optical fiber serial ports to the standby optical fiber serial ports of the corresponding merging units and determining the communication link to which the fault belongs to obtain a determination result of the faulty communication link includes: Connect the optical fiber serial ports to the spare optical fiber serial ports of the corresponding merging units, collect the optical signals of each communication link, and convert them into digital signal data; Processing the digital signal data of each communication link to obtain synchronous DC voltage amplitude data of each communication link; Compare the synchronous DC voltage amplitude data of each communication link with the actual line voltage. If the synchronous DC voltage amplitude data of all communication links are abnormal to the actual line voltage, it is determined that the DC voltage divider is faulty. If the synchronous DC voltage amplitude data of all communication links are consistent with the actual line voltage, the difference between the synchronous DC voltage amplitude data of each communication link is calculated, and the difference is compared with the preset accuracy error. If the difference is less than the preset accuracy error, it is judged that the DC voltage transformer is not faulty. If the difference of one of the communication links is higher than the preset accuracy error, it is judged that the communication link is faulty.

8. The portable DC voltage transformer fault detection method according to claim 6, characterized in that: The method of selecting an optical fiber serial port to connect to the input end of the merging unit in the faulty communication link, detecting the optical fiber loop and the optical fiber signal in the faulty communication link, and obtaining the faulty communication link inspection result includes: Select an optical fiber serial port to connect to the input end of the merging unit in the faulty communication link, collect the optical signal, and convert it into digital signal data; Optical power detection is performed based on the digital signal data. If the optical power is lower than the preset value, the optical fiber serial port is connected to the output end of the remote module in the faulty communication link to detect the optical power of the remote module. If the optical powers of the input end of the merging unit and the output end of the remote module are both lower than the preset range, it is determined that there is a fault in the remote module; if the optical power of the input end of the merging unit is lower than the preset range, and the optical power of the remote module is higher than the preset range, it is determined that there is a fault in the optical fiber between the remote module and the merging unit.

9. The portable DC voltage transformer fault detection method according to claim 6, characterized in that: According to the inspection result of the faulty communication link, the A / D conversion module is connected to the output ends of the secondary voltage divider and the differential amplifier respectively, and an optical fiber serial port is selected to be connected to the output end of the remote module in the faulty communication link, and the fault position in the faulty communication link is judged to obtain the fault position judgment result in the faulty communication link, including: When the optical power of the remote module in the optical fiber loop and the optical fiber signal detection result in the faulty communication link is within a preset range, the A / D conversion module is connected to the output ends of the secondary voltage divider and the differential amplifier respectively, and an optical fiber serial port is connected to the output end of the remote module in the faulty communication link, and the voltage signal data of the output ends of the secondary voltage divider and the differential amplifier and the optical fiber serial digital signal data of the output end of the remote module are respectively collected and converted into digital quantity signal data respectively; Processing the digital signal data of the secondary voltage divider, the output end of the differential amplifier and the output end of the remote module to obtain the synchronous DC voltage amplitude data of the secondary voltage divider, the output end of the differential amplifier and the output end of the remote module; Taking the synchronous DC voltage amplitude data at the output end of the secondary voltage divider as a reference, the synchronous DC voltage amplitude data at the output end of the differential amplifier and the output end of the remote module are compared with the synchronous DC voltage amplitude data at the output end of the secondary voltage divider. If there are errors in the synchronous DC voltage amplitude data at the output end of the differential amplifier and the output end of the remote module and the errors are consistent, it is determined that the differential amplifier is faulty. If there is no error in the synchronous DC voltage amplitude data at the output end of the differential amplifier and there is an error in the synchronous DC voltage amplitude data at the output end of the remote module, it is determined that the remote module is faulty. If there is no error in the synchronous DC voltage amplitude data at the output end of the differential amplifier and the output end of the remote module, it is determined that the secondary voltage divider is faulty.

10. The portable DC voltage transformer fault detection method according to claim 7 or 9, characterized in that: The data processing includes: Extract digital signal data in a 200ms time window; The digital signal data is calculated using generalized polynomial fitting to obtain the DC voltage amplitude data; The interrupt signal generated by the high constant temperature crystal oscillator is used through FPGA to interrupt the A / D conversion module and the acquisition of the optical fiber serial port, and the digital signal data is time-stamped through the interrupt control; The digital signal data is subjected to a secondary linear interpolation calculation according to the time scale to obtain the synchronous DC voltage amplitude data.

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