Fault recording device, method and storage medium

Abstract

This invention discloses a fault recording device, method, and storage medium. The fault recording device is used to detect faults in AC / DC power supplies and includes: a DC circuit detection module, an AC circuit detection module, and a processor. The DC circuit detection module, based on the magnetic modulation principle, measures the target DC current of a target DC branch in the AC / DC power supply and inputs the target DC current into the processor. The AC circuit detection module, based on the Hall effect principle, measures the target AC current of a target AC branch in the AC / DC power supply and inputs the target AC current into the processor. The processor is used to determine whether a fault exists in the target DC branch based on the target DC current and whether a fault exists in the target AC branch based on the target AC current. This fault recording device can simultaneously and continuously monitor faults in both AC and DC branches of the AC / DC power supply, and the fault detection accuracy is high.

Description

Technical Field

[0001] This invention relates to the field of circuit testing technology, and in particular to fault recording devices, methods and storage media. Background Technology

[0002] Substation AC / DC power supplies play a crucial role in providing stable power to secondary equipment such as relay protection, automation, and communication systems within substations. The technical specifications for substation AC / DC power supply systems have clear and stringent requirements regarding input voltage asymmetry, voltage accuracy, and insulation levels. If abnormalities occur in the substation AC / DC power supply system, such as reduced insulation, loop reversals, or voltage imbalances, minor issues can lead to reduced lifespan of secondary equipment and poor communication quality; serious issues can result in malfunctions such as switch malfunctions or failures to operate, and communication interruptions with the dispatch data network. Therefore, fault detection of AC / DC power supplies is extremely important.

[0003] Currently, the centralized fault recording devices configured in substations and the portable fault recording devices available on the market can only sample and monitor conventional current and voltage. They cannot simultaneously and continuously monitor large AC current and DC leakage current. There is a lack of effective monitoring methods to detect whether there are faults in AC and DC power supplies, which brings great difficulties to on-site troubleshooting and fault analysis. Summary of the Invention

[0004] This invention provides a fault recording device, method, and storage medium to solve the technical problem in related technologies that it is impossible to simultaneously and continuously monitor large AC current and DC leakage current, and there is a lack of effective monitoring means to detect whether there is a fault in AC or DC power supply.

[0005] According to one aspect of the present invention, a fault recording device is provided for detecting faults in AC / DC power supplies. The fault recording device includes: a DC circuit detection module, an AC circuit detection module, and a processor, wherein the processor is connected to the DC circuit detection module and the AC circuit detection module respectively.

[0006] The DC circuit detection module, based on the principle of magnetic modulation, measures the target DC current of the target DC branch in the AC / DC power supply and inputs the target DC current to the processor.

[0007] The AC circuit detection module is based on the Hall effect principle, measures the target AC current of the target AC branch in the AC / DC power supply, and inputs the target AC current to the processor;

[0008] The processor is used to determine whether there is a fault in the target DC branch based on the target DC current, and to determine whether there is a fault in the target AC branch based on the target AC current.

[0009] According to another aspect of the present invention, a fault recording method is provided, the method being applied to a fault recording apparatus as described in the first aspect, the method comprising:

[0010] The processor acquires the target DC current of the target DC branch in the AC / DC power supply input from the DC circuit detection module;

[0011] The processor acquires the target AC current of the target AC branch in the AC / DC power supply input by the AC circuit detection module.

[0012] The processor determines whether there is a fault in the target DC branch based on the target DC current, and determines whether there is a fault in the target AC branch based on the target AC current.

[0013] According to another aspect of the present invention, a computer-readable storage medium is provided, the computer-readable storage medium storing computer instructions for causing a processor to execute and implement the fault recording method according to any embodiment of the present invention.

[0014] In the technical solution of this invention embodiment, the fault recording device is used to detect faults in AC / DC power supplies, including: a DC circuit detection module, an AC circuit detection module, and a processor, wherein the processor is connected to both the DC circuit detection module and the AC circuit detection module; the DC circuit detection module measures the target DC current of the target DC branch in the AC / DC power supply based on the magnetic modulation principle, and inputs the target DC current into the processor; the AC circuit detection module measures the target AC current of the target AC branch in the AC / DC power supply based on the Hall effect principle, and inputs the target AC current into the processor; the processor is used to determine whether there is a fault in the target DC branch based on the target DC current, and to determine whether there is a fault in the target AC branch based on the target AC current. It has the following technical advantages: Firstly, because it has both a DC circuit detection module and an AC circuit detection module, the fault recording device can simultaneously achieve continuous monitoring of faults in both AC and DC branches of the AC / DC power supply. Secondly, the AC circuit detection module detects the target AC current based on the Hall effect principle, enabling continuous measurement of large currents in the AC system with high measurement accuracy, thereby improving the accuracy of fault detection. Thirdly, the DC circuit detection module detects the target DC current based on the magnetic modulation principle, enabling continuous measurement of small currents in the DC system with high measurement accuracy, thereby improving the accuracy of fault detection.

[0015] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0017] Figure 1 This is a schematic diagram of the structure of a fault recording device according to an embodiment of the present invention;

[0018] Figure 2 This is a schematic diagram of an AC circuit detection module.

[0019] Figure 3 This is a schematic diagram of a DC circuit detection module.

[0020] Figure 4 This is a schematic diagram of the structure of a fault recording device according to another embodiment of the present invention;

[0021] Figure 5 This is a schematic flowchart of a fault recording method according to an embodiment of the present invention;

[0022] Figure 6 This is a schematic diagram of the DC branch being tested using a DC circuit detection module;

[0023] Figure 7 This is a schematic diagram of an AC branch circuit being tested using an AC circuit detection module;

[0024] Figure 8 This is another schematic diagram of detecting AC branches based on the AC circuit detection module. Detailed Implementation

[0025] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0026] It should be noted that the terms "target," "first," "second," etc., used in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the term "comprising" and any variations thereof are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0027] Figure 1 This is a schematic diagram of a fault recording device according to an embodiment of the present invention. This embodiment is applicable to scenarios where faults in both the DC and AC branches of an AC / DC power supply need to be detected simultaneously. Figure 1 As shown, the fault recording device provided in this embodiment includes the following modules: DC circuit detection module 12, AC circuit detection module 13, and processor 11.

[0028] The processor 11 is connected to the DC circuit detection module 12 and the AC circuit detection module 13 respectively.

[0029] The DC circuit detection module 12 is based on the magnetic modulation principle, measures the target DC current of the target DC branch in the AC / DC power supply, and inputs the target DC current to the processor 11.

[0030] The AC circuit detection module 13 is based on the Hall effect principle, measures the target AC current of the target AC branch in the AC / DC power supply, and inputs the target AC current to the processor 11.

[0031] The processor 11 is used to determine whether there is a fault in the target DC branch based on the target DC current and to determine whether there is a fault in the target AC branch based on the target AC current.

[0032] In this embodiment, the AC / DC power supply refers to a power supply capable of outputting both direct current (DC) and alternating current (AC). The DC power in the AC / DC power supply is obtained by rectifying the AC power supply; the two are interconnected and influence each other. The AC / DC power supply in this embodiment can be an AC / DC power supply configured within a substation, or it can be an AC / DC power supply used in other scenarios. This embodiment is not limited to these limitations.

[0033] This embodiment provides a fault recording device for detecting faults in AC / DC power supplies. This fault recording device can measure both high currents (0-200A) in AC systems and simultaneously and continuously and accurately measure low currents (0-500mA) in DC systems. The AC system in this embodiment includes multiple AC branches, and the DC system includes multiple DC branches.

[0034] The target DC branch refers to the DC branch currently being detected. The target AC branch refers to the AC branch currently being detected.

[0035] The AC circuit detection module in this embodiment is based on the Hall effect principle to detect the target AC current in the target AC branch.

[0036] More specifically, the AC circuit detection module in this embodiment uses a Hall current sensor with a Rogowski coil to measure the AC current.

[0037] Figure 2 This is a schematic diagram of the structure of an AC circuit detection module. (Example) Figure 2 As shown, the AC circuit detection module includes: a first core 131, a Hall element 132, a secondary coil 133, and an amplifier circuit (AMP) 134.

[0038] The first core 131 is a non-closed structure and has a first through hole 135. The first core 131 includes a first end 137 and a second end 138, with a gap 136 between the first end 137 and the second end 138.

[0039] The target AC branch 139 passes through the first through hole 135.

[0040] A Hall element 132 is disposed at the gap 136 of the first core 131. The first end of the Hall element 132 is connected to the first input terminal of the amplifier circuit 134, and the second end of the Hall element 132 is connected to the second input terminal of the amplifier circuit 134. The output terminal of the amplifier circuit 134 is connected to the secondary coil 133.

[0041] After the secondary coil 133 is wound around the first end 137 and the second end 138 of the first core 131, it forms the output terminal of the AC circuit detection module, which is used to output the target AC current.

[0042] In this embodiment, the first core 131 can be a non-closed iron core. Alternatively, the first core 131 can be a non-closed Rogowski coil. Figure 2The first core 131 shown is a non-closed annular shape; however, it can be understood that the first core 131 can also be other non-closed shapes. The gap 136 in this embodiment can also be referred to as an air gap.

[0043] Optionally, the first core 131 in this embodiment is flexible to meet the needs of various on-site measurements, fault location, etc.

[0044] The principle of the AC circuit detection module is as follows: The AC current flowing through the target AC branch 139 (also called the primary current, and the target AC branch can also be called the primary conductor) forms a magnetic field at the gap 136. Based on the Hall effect, the Hall element 132 at the gap 136 will induce a potential difference under the influence of the magnetic field at the gap 136. This results in current input to the amplifier circuit 134. The amplifier circuit 134 receives the input from the Hall element 132, and the output secondary current flows through the secondary coil 133. It can be understood that the magnetic field generated by the secondary current in the first core 131 cancels out the magnetic field generated by the primary current at the gap 136. Therefore, the current output by the secondary measurement can accurately reflect the magnitude of the primary current. This method meets the AC current channel range requirement of 0-200A for the fault recording device, enabling the fault recording device to measure large currents in the AC system in real time.

[0045] Alternatively, please continue to refer to Figure 2 The first terminal of Hall element 132 is connected to the first input terminal of amplifier circuit 134 through first resistor R1, and the second terminal of Hall element 132 is connected to the second input terminal of amplifier circuit 134 through second resistor R2. The output terminal of AC circuit detection module is connected to one end of measuring resistor R3, and the other end of measuring resistor R3 is grounded.

[0046] Optionally, the first core 131 in this embodiment can be a Rogowski coil, which has advantages such as wide bandwidth, small size, and large measurable current. The first core 131 in this embodiment can also be flexible. In this embodiment, a Hall element 132 is placed at the gap 136 of the first core 131 to prevent saturation of the first core 131, thus ensuring that the current output by the secondary measurement always changes with the primary current, accurately reflecting the magnitude of the primary current.

[0047] The AC circuit detection module in this embodiment is based on the Hall effect principle and uses the Rogowski coil method, which has the advantages of wide bandwidth, small size and large measurable current, to measure current. It also uses an integrator circuit to design a flexible current transformer (CT), which has the characteristics of fast response speed and no saturation, and is suitable for AC, especially wideband and high current measurement. At the same time, the flexible design with a movable opening expands the application of current measurement and can meet the needs of various field measurement and fault location.

[0048] The DC circuit detection module in this embodiment is based on the principle of magnetic modulation to detect the target DC current in the target DC branch.

[0049] Figure 3 This is a schematic diagram of the structure of a DC circuit detection module. (Example) Figure 3 As shown, the DC circuit detection module provided in this embodiment includes: an excitation current generator 121, an AC excitation coil W1, a second core 122, and a detection coil W3.

[0050] The second core 122 is a closed structure and has a second through hole 123. An AC excitation coil W1 is wound around the first region of the second core 122. An excitation current generator 121 is used to input an excitation signal to both ends of the AC excitation coil W1.

[0051] The target DC branch 124 penetrates the second through hole 123.

[0052] The detection coil W3 is wound around the second region of the second core 122, and the detection coil W3 is used to output the target DC current.

[0053] In this embodiment, the excitation signal Is can be a triangular wave signal, but it can also be a square wave, sawtooth wave, sine wave, etc. This embodiment is not limited to these. The second core 122 can be an iron core. Similar to the first core 131, the second core 122 can also be flexible.

[0054] The DC circuit detection module in this embodiment is a DC-specific leakage current small-signal measurement CT based on the magnetic modulation principle. It accurately measures mA-level DC current signals and adopts a through-hole input design, that is, the target DC branch 124 is set through the second through hole 123, which can meet different application requirements.

[0055] The following uses a triangular wave excitation signal as an example to illustrate the implementation principle of the DC circuit detection module: A triangular wave excitation signal flows through W1. If the current in the target DC branch 124 (also known as the primary side) is zero, the output of the detection coil W3 is a square wave (or a straight line). If the current in the target DC branch 124 is not zero, the output of the detection coil W3 is a pulse width modulation wave due to the magnetic field modulation effect generated by the current in the target DC branch 124. At this time, the change between the positive and negative pulses is proportional to the target DC current IO.

[0056] The DC circuit detection module provided in this embodiment can meet the DC current channel range requirement of the waveform recorder (0-500mA), enabling the waveform recorder to accurately measure the primary leakage current I0. Secondly, it abandons the traditional transmitter design approach, adopting an integrated, portable design that is small in size and easy to install in confined protection cabinets for measurement, adapting to scenarios involving mobile fault location. Furthermore, it integrates multiple DC-dedicated leakage current small-signal measurement CTs onto the waveform recorder, allowing simultaneous measurement of multiple DC branches, facilitating fault location.

[0057] This embodiment provides a fault recording device for detecting faults in AC / DC power supplies. The device includes a DC circuit detection module, an AC circuit detection module, and a processor, with the processor connected to both the DC and AC circuit detection modules. The DC circuit detection module, based on the magnetic modulation principle, measures the target DC current of a target DC branch in the AC / DC power supply and inputs the target DC current to the processor. The AC circuit detection module, based on the Hall effect principle, measures the target AC current of a target AC branch in the AC / DC power supply and inputs the target AC current to the processor. The processor determines whether a fault exists in the target DC branch based on the target DC current and whether a fault exists in the target AC branch based on the target AC current. It has the following technical advantages: Firstly, because it has both a DC circuit detection module and an AC circuit detection module, the fault recording device can simultaneously achieve continuous monitoring of faults in both AC and DC branches of the AC / DC power supply. Secondly, the AC circuit detection module detects the target AC current based on the Hall effect principle, enabling continuous measurement of large currents in the AC system with high measurement accuracy, thereby improving the accuracy of fault detection. Thirdly, the DC circuit detection module detects the target DC current based on the magnetic modulation principle, enabling continuous measurement of small currents in the DC system with high measurement accuracy, thereby improving the accuracy of fault detection.

[0058] Figure 4 This is a schematic diagram of a fault recording device according to another embodiment of the present invention. Figure 1 Based on the illustrated embodiment, the other modules included in the fault recording device will be described in detail. For example... Figure 4 As shown, the fault recording device provided in this embodiment also includes a resistance detection module connected to the processor.

[0059] The resistance detection module is used to detect the resistance to ground of the positive DC terminal or the negative DC terminal in the AC / DC power supply, and input the resistance to ground to the processor.

[0060] The processor determines whether there is a DC branch with a ground fault in the AC / DC power supply based on the resistance to ground.

[0061] The fault recording device in this embodiment employs an embedded hardware platform and an embedded software platform, fundamentally ensuring the stability and reliability of the device and guaranteeing its measurement stability.

[0062] like Figure 4 As shown, the device employs a Symmetric Multiprocessing (SMP) multi-core processing architecture. It is equipped with a hard drive connected to a serial bus interface, enabling the device to process and store massive amounts of current signals. Real-time software is designed and developed based on embedded concepts, and the Real-Time (RT) operating system RTLinux is used to ensure the real-time performance and stability of the device software. The device also features a file system, a graphical user interface, and application programs.

[0063] The device has memory, such as read-only memory (ROM), synchronous dynamic random-access memory (SDRAM), and random access memory (RAM).

[0064] Optionally, the fault recording device provided in this embodiment further includes an AC circuit analog-to-digital (A / D) conversion circuit, which is connected to the AC circuit detection module and is used to realize the analog-to-digital conversion of the output data of the AC circuit detection module.

[0065] Optionally, the fault recording device provided in this embodiment further includes: a DC circuit A / D conversion circuit, which is connected to the DC circuit detection module and is used to realize the analog-to-digital conversion of the output data of the DC circuit detection module.

[0066] Optionally, the fault recording device provided in this embodiment further includes: a resistor A / D conversion circuit, connected to the resistor detection module, used to realize analog-to-digital conversion of the output data of the resistor detection module.

[0067] In one embodiment, the fault recording device further includes an alternating current signal source, used to inject an alternating current signal into the DC system of the AC / DC power supply when it is determined that there is a DC branch in the AC / DC power supply that has experienced a ground fault.

[0068] In one embodiment, the fault recording device further includes a human-machine interface for receiving user-input commands or displaying measurement results to the user.

[0069] Human-computer interaction interfaces can include: input units, such as keyboards and mice; and output units, such as various types of displays and speakers.

[0070] In one embodiment, the fault recording device may further include a communication unit, such as a network interface card (NIC), a modem, a wireless transceiver, etc. The communication unit allows the fault recording device to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0071] The fault recording device in this embodiment may include multiple DC circuit detection modules and multiple AC circuit detection modules to detect multiple branches. The DC circuit detection module, AC circuit detection module, and resistance detection module in this embodiment, along with other modules of the fault recording device (referred to as the host computer in this embodiment), can be separately configured and connected to the host computer via wired or wireless communication.

[0072] In this embodiment, the fault recording device can display the waveforms of multiple DC and AC branch detection results on the same time axis, facilitating comprehensive fault analysis. Simultaneously, the sampling clamps have been improved to facilitate on-site measurement and fault location for different installation environments and wiring configurations. It integrates AC / DC system grounding fault location functions, thereby improving fault finding efficiency.

[0073] In this embodiment, the DC system measurement branch and the AC system measurement channel are divided into two windows. In each window, multiple branch measurement data waveforms are displayed on the same time axis, allowing for vertical and horizontal zooming, or overlaying of multiple waveforms for detailed comparison. The window displays the effective and instantaneous values ​​of each measurement branch. The measurement data can be displayed as a vector diagram. This implementation improves user experience and increases fault location efficiency.

[0074] When the AC current A / D conversion circuit of the fault recording device has a measured value input, the device acquires the data input from the AC circuit detection module and records the data; when the DC current A / D conversion circuit of the device has a measured value input, the device acquires the data input from the DC circuit detection module and records the data; when the resistance A / D conversion circuit of the device has a measured value input, the device acquires the data input from the resistance detection module and records the data.

[0075] The fault recording device provided in this embodiment can further improve the efficiency of fault finding.

[0076] The following describes in detail the processing procedure of the processor in the fault recording device to achieve fault detection.

[0077] Figure 5This is a schematic flowchart of a fault recording method according to an embodiment of the present invention. This embodiment can be implemented by a processor in a fault recording device. The processor can be implemented by software and / or hardware. Figure 5 As shown, the fault recording method provided in this embodiment includes the following steps:

[0078] Step 501: The processor obtains the target DC current of the target DC branch in the AC / DC power supply input by the DC circuit detection module.

[0079] Step 502: The processor obtains the target AC current of the target AC branch in the AC / DC power supply input by the AC circuit detection module.

[0080] Step 503: The processor determines whether there is a fault in the target DC branch based on the target DC current, and determines whether there is a fault in the target AC branch based on the target AC current.

[0081] In one implementation, the processor determines whether a target DC branch has a fault based on the target DC current in the following way: when the ground resistance input by the resistance detection module is less than a preset resistance threshold, the processor determines that there is a DC branch in the AC / DC power supply with a ground fault; after injecting an alternating current signal into the DC system of the AC / DC power supply, the processor determines the waveform of the target DC current; if the waveform of the target DC current is a non-linear periodic wave, the processor determines that there is a fault in the target DC branch, and identifies the location where the waveform of the target DC current in the target DC branch changes from a non-linear periodic wave to a straight line as the fault point; if the waveform of the target DC current is a straight line, the processor determines that there is no fault in the target DC branch; if the waveform of the target DC current is an irregular waveform, the processor determines that there is a fault in the next-level load branch of the target DC branch.

[0082] The above process will be illustrated with a specific example below. Figure 6 This is a schematic diagram illustrating the detection of the DC branch using a DC circuit detection module. The resistance to ground input to the resistance detection module refers to the resistance to ground of either the positive or negative DC terminal of the AC / DC power supply. (Corresponding to...) Figure 6 In this diagram, the positive DC terminal refers to +KM, and the negative DC terminal refers to -KM. Multiple DC branches are connected to the positive and negative DC terminals. Figure 6The following explanation uses a single DC branch as an example. When the resistance to ground input by the resistance detection module is less than the preset resistance threshold, it indicates a ground fault at the positive or negative terminal of the DC system, meaning there is a DC branch with a ground fault in the AC / DC power supply. It is necessary to identify the faulty DC branch from among multiple branches. At this point, after injecting an alternating current signal into the DC system of the AC / DC power supply, the DC current on each DC branch is acquired through the DC circuit detection module, and the waveform of each DC current is determined. When the branch capacitance is small, the DC current transformer (CT) is placed at the bus terminal of the branch. Then, the waveform of the DC current is used to determine whether a fault has occurred in the DC branch: if the waveform of the target DC current is a straight line, it is determined that the target DC branch is not faulty; if the waveform of the target DC current is an irregular waveform, it is determined that the next-level load branch of the target DC branch has a fault. If the waveform of the target DC current is a non-linear periodic wave, such as a sine wave, then on the target DC branch, move the DC circuit detection module from the bus end to the load end until the waveform of the target DC current changes from a non-linear periodic wave to a straight line. This indicates that a ground fault has occurred at the location of the change in the DC current waveform. Figure 6 In this case, assuming that at position L1, the waveform of the target DC current changes from a non-linear periodic wave to a straight line, then position L1 is determined to be the fault point.

[0083] It should be noted that, as Figure 6 As shown, when using the DC circuit detection module to detect the DC current in the DC branch, the wires connected to the positive DC terminal and the wires connected to the negative DC terminal in the DC branch are both placed at the second through hole of the second core.

[0084] For example, the preset resistance threshold can be 100KΩ.

[0085] In one implementation, the processor determines whether a fault exists in the target AC branch based on the target AC current in the following ways: when the residual current of the AC bus in the AC / DC power supply is greater than a preset first current threshold, it is determined that there is an AC branch with a ground fault in the AC / DC power supply, and the target AC current is obtained; when the target AC branch is a non-zero-load branch, when the target AC current is greater than a preset second current threshold, it is determined that there is a fault in the target AC branch, and the location where the target AC current in the target AC branch changes from being greater than the preset second current threshold to being less than or equal to the preset second current threshold is determined as the fault point; when the target AC branch is a zero-load branch, when the difference between the target AC current and the AC current of another AC branch is greater than a preset third current threshold, it is determined that the target AC branch and / or the other AC branch has a fault; wherein, the load of the target AC branch and the load of the other AC branch are the same load.

[0086] Optionally, when the target AC branch is a common zero-load branch, the fault recording method provided in this embodiment further includes: determining the position in the target AC branch where the difference changes from being greater than a preset third current threshold to being less than or equal to the preset third current threshold as a first position; determining the position in another AC branch where the difference changes from being greater than a preset third current threshold to being less than or equal to the preset third current threshold as a second position; if the difference of the target AC current at both ends of the first position is greater than the preset third current threshold, then the first position is determined to be a fault point; if the difference of the AC current at both ends of the second position is greater than the preset third current threshold, then the second position is determined to be a fault point.

[0087] The above process is illustrated with two specific examples below.

[0088] Figure 7 This is a schematic diagram illustrating the testing of an AC branch using an AC circuit detection module. For example... Figure 7 As shown, the target AC branch is a non-common-zero load branch. The residual current of the AC bus in an AC / DC power supply refers to I. sM =I aM +I bM +I cM +I nM , among which, I aM Referring to Figure 7 The current I on line A bM It refers to Figure 7 The current I on line B cM It refers to Figure 7 The current I on line B nM It refers to Figure 7 The current on the neutral line N. If I sM If the current exceeds a preset first current threshold, a ground fault is determined to exist in the AC system; that is, an AC branch with a ground fault exists. It is necessary to identify the faulty AC branch from among multiple AC branches. Figure 7 In the diagram, the AC circuit detection module (represented by CT) clamps the A, B, C, and neutral lines of the target AC branch. The target AC current I... s =I a +I b +I c +I n I a I b I c and I n like Figure 7 As shown in the diagram, when the target AC current exceeds a preset second current threshold, a fault is determined to exist in the target AC branch. Figure 7The example is illustrated using a second current threshold of 0. The AC current transformer (CT) is moved from the bus end to the load end until the target AC current changes from being greater than the preset second current threshold to being less than or equal to the preset second current threshold. The location where the AC current changes is determined as the fault point. Figure 7 In this context, If represents the AC current at the fault point. It should be noted that the target AC current refers to the residual current phasor of the cross-section of the target AC branch.

[0089] Figure 8 This is another schematic diagram illustrating the detection of AC branches using an AC circuit detection module. For example... Figure 8 As shown, the target AC branch is a zero-load branch. That is, the load of the target AC branch is the same as the load of the other AC branch. Figure 8 Taking the AC branch on the left as the target AC branch and the AC branch on the right as another AC branch as an example, the AC circuit detection module corresponding to the target AC branch is represented by CT1, and the AC circuit detection module corresponding to the other AC branch is represented by CT2. When the absolute value of the difference between the target AC current and the AC current of the other AC branch is greater than the preset third current threshold, that is:

[0090] |I s1 -I s2 |=|(I a1 +I b1 +I c1 +I n1 )-(I a2 +I b2 +I c2 +I n2 If the current exceeds the preset third current threshold, it is determined that at least one branch of the target AC branch and the other AC branch has failed.

[0091] At this point, two AC CTs are moved from the busbar end to the load end; that is, CT1 is moved from busbars A1, B1, C1, and N1 to the load end, and CT2 is moved from busbars A2, B2, C2, and N2 to the load end, until |I s1 -I s2 The current changes from being greater than the preset third current threshold to being less than or equal to the preset third current threshold. Figure 8 The example uses a third current threshold of 0. The position in the target AC branch where the difference changes from being greater than the preset third current threshold to being less than or equal to the preset third current threshold is defined as the first position. Figure 8 Position S1 is shown in the diagram. In another AC branch, the position where the difference changes from being greater than a preset third current threshold to being less than or equal to the preset third current threshold is determined as the second position, as shown in the diagram. Figure 8 The position S2 is shown in the diagram. Figure 8 In the figure, If represents the AC current at the fault point.

[0092] After identifying S1 and S2, it is necessary to determine which location is the actual fault point. This requires detecting the difference in target AC current at both ends of the first and second locations. In this embodiment, the two ends of the first location refer to the upper and lower sides of the first location, and the two sides of the second location refer to the upper and lower sides of the second location. Figure 8 In this context, "above the first position" refers to a position located above the first position and within a preset distance threshold. "Below the first position" refers to a position located below the first position and within a preset distance threshold.

[0093] Figure 8 The example uses a preset third current threshold of 0.05.

[0094] If |I s,S1,L -I s,S1,R If | > 0.05A, the first location is determined to be the fault point; if |I s,S2,L -I s,S2,R |>0.05A, the second location is determined to be the fault point. Where I s,S1,L This refers to the alternating current I on the upper side of S1. s,S1,R This refers to the alternating current on the lower side of S1. s,S2,L This refers to the alternating current on the upper side of S2. I s,S2,R This refers to the alternating current on the lower side of S2.

[0095] If |I s,S1,L -I s,S1,R |>0.05A and|I s,S2,L -I s,S2,R If |>0.05A, then both the first and second positions are determined to be fault points.

[0096] In one case, |I s,S1,L -I s,S1,R |>0.05A, and |I s,S2,L -I s,S2,R If |≤0.05A, the first location is determined to be the fault point.

[0097] In another case, |I s,S1,L -I s,S1,R |≤0.05A, and |I s,S2,L -I s,S2,R |>0.05A, the second location is determined to be the fault point.

[0098] It should be noted that the AC current of the AC branch in this embodiment refers to the residual current of the cross-section of the AC branch. The preset first current threshold, preset second current threshold, and preset third current threshold in this embodiment can be the same or different.

[0099] The fault recording method provided in this embodiment can simultaneously achieve continuous monitoring of faults in both AC and DC branches of an AC / DC power supply, while also achieving high accuracy in fault detection.

[0100] In some embodiments, the fault recording method may be implemented as a computer program or computer instructions tangibly contained in a computer-readable storage medium, such as the memory of the fault recording device. In some embodiments, part or all of the computer program may be loaded and / or installed onto the fault recording device via ROM and / or a communication unit. When the computer program is loaded into memory and executed by the processor, one or more steps of the fault recording method described above may be performed. Alternatively, in other embodiments, the processor may be configured to perform the fault recording method described above by any other suitable means (e.g., by means of firmware).

[0101] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0102] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0103] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0104] To provide user interaction, the systems and techniques described herein can be implemented on a fault recording device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the fault recording device. Other types of devices can also be used to provide user interaction; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0105] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0106] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0107] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0108] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A fault recording device, characterized in that, The fault recording device is used to detect faults in AC / DC power supplies. The fault recording device includes: a DC circuit detection module, an AC circuit detection module, and a processor. The processor is connected to the DC circuit detection module and the AC circuit detection module, respectively. The DC circuit detection module, based on the principle of magnetic modulation, measures the target DC current of the target DC branch in the AC / DC power supply and inputs the target DC current to the processor. The AC circuit detection module is based on the Hall effect principle, measures the target AC current of the target AC branch in the AC / DC power supply, and inputs the target AC current to the processor; The processor is used to determine whether there is a fault in the target DC branch based on the target DC current, and to determine whether there is a fault in the target AC branch based on the target AC current; The processor determines whether a target DC branch has a fault based on the target DC current, including: when the ground resistance input by the resistance detection module is less than a preset resistance threshold, the processor determines that a DC branch in the AC / DC power supply has a ground fault; after injecting an alternating current signal into the DC system of the AC / DC power supply, the processor determines the waveform of the target DC current; if the waveform of the target DC current is a non-linear periodic wave, the processor determines that the target DC branch has a fault, and identifies the location where the waveform of the target DC current in the target DC branch changes from a non-linear periodic wave to a linear wave as the fault point; if the waveform of the target DC current is a linear wave, the processor determines that the target DC branch does not have a fault; if the waveform of the target DC current is an irregular waveform, the processor determines that the next-level load branch of the target DC branch has a fault.

2. The apparatus according to claim 1, characterized in that, The AC circuit detection module includes: a first core, a Hall element, a secondary coil, and an amplifier circuit; The first core is a non-closed structure and has a first through hole. The first core includes a first end and a second end, and there is a gap between the first end and the second end. The target AC branch line passes through the first through hole; The Hall element is disposed in the gap of the first core, the first end of the Hall element is connected to the first input terminal of the amplifier circuit, the second end of the Hall element is connected to the second input terminal of the amplifier circuit, and the output terminal of the amplifier circuit is connected to the secondary coil. After the secondary coil is wound around the first end and the second end of the first core, it forms the output terminal of the AC circuit detection module, which is used to output the target AC current.

3. The apparatus according to claim 2, characterized in that, The first end of the Hall element is connected to the first input terminal of the amplifier circuit through a first resistor, and the second end of the Hall element is connected to the second input terminal of the amplifier circuit through a second resistor. The output terminal of the AC circuit detection module is connected to one end of the measuring resistor, and the other end of the measuring resistor is grounded.

4. The apparatus according to claim 1, characterized in that, The DC circuit detection module includes: an excitation current generator, an AC excitation coil, a second core, and a detection coil; The second core is a closed structure and has a second through hole; the AC excitation coil is wound around the first region of the second core, and the excitation current generator is used to input an excitation signal to both ends of the AC excitation coil; The target DC branch passes through the second through hole; The detection coil is wound around the second region of the second core, and the detection coil is used to output the target DC current.

5. The apparatus according to claim 1, characterized in that, The device further includes a resistance detection module connected to the processor. The resistance detection module is used to detect the resistance to ground of the positive DC terminal or the negative DC terminal in the AC / DC power supply, and input the resistance to ground to the processor. The processor determines whether there is a DC branch in the AC / DC power supply that has a ground fault based on the ground resistance.

6. A fault recording method, characterized in that, The method is applied to the fault recording device as described in any one of claims 1 to 5, and the method includes: The processor acquires the target DC current of the target DC branch in the AC / DC power supply input from the DC circuit detection module; The processor acquires the target AC current of the target AC branch in the AC / DC power supply input by the AC circuit detection module. The processor determines whether there is a fault in the target DC branch based on the target DC current, and determines whether there is a fault in the target AC branch based on the target AC current; The processor determines whether a target DC branch has a fault based on the target DC current, including: when the ground resistance input by the resistance detection module is less than a preset resistance threshold, the processor determines that a DC branch in the AC / DC power supply has a ground fault; after injecting an alternating current signal into the DC system of the AC / DC power supply, the processor determines the waveform of the target DC current; if the waveform of the target DC current is a non-linear periodic wave, the processor determines that the target DC branch has a fault, and identifies the location where the waveform of the target DC current in the target DC branch changes from a non-linear periodic wave to a linear wave as the fault point; if the waveform of the target DC current is a linear wave, the processor determines that the target DC branch does not have a fault; if the waveform of the target DC current is an irregular waveform, the processor determines that the next-level load branch of the target DC branch has a fault.

7. The method according to claim 6, characterized in that, The step of determining whether the target AC branch has a fault based on the target AC current includes: When the residual current of the AC bus in the AC / DC power supply is greater than a preset first current threshold, it is determined that there is an AC branch in the AC / DC power supply that has a ground fault, and the target AC current is obtained. When the target AC branch is a non-zero load branch, if the target AC current is greater than a preset second current threshold, it is determined that the target AC branch has a fault, and the location in the target AC branch where the target AC current changes from being greater than the preset second current threshold to being less than or equal to the preset second current threshold is determined as the fault point. When the target AC branch is a zero-load branch, if the absolute value of the difference between the target AC current and the AC current of another AC branch is greater than a preset third current threshold, it is determined that the target AC branch and / or the other AC branch has a fault; wherein, the load of the target AC branch and the load of the other AC branch are the same load.

8. The method according to claim 7, characterized in that, When the target AC branch is a common zero-load branch, the method further includes: The first position is defined as the location in the target AC branch where the difference changes from being greater than the preset third current threshold to being less than or equal to the preset third current threshold. In the other AC branch, the position where the difference changes from being greater than the preset third current threshold to being less than or equal to the preset third current threshold is determined as the second position; If the difference between the target AC currents at both ends of the first position is greater than the preset third current threshold, then the first position is determined to be a fault point. If the difference between the alternating currents at the two ends of the second position is greater than the preset third current threshold, then the second position is determined to be a fault point.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that cause a processor to execute the fault recording method according to any one of claims 6 to 8.

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