Insulation monitoring device of IT system

Abstract

The utility model discloses an insulation monitoring device of an IT system, and relates to the technical field of power distribution systems. The insulation monitoring device comprises a power board, a sampling board and a logic board, wherein the power panel is electrically connected with the IT system and is used for injecting AMP monitoring pulses or alternating current pulses into the IT system; the sampling board comprises a bus dynamic switching sampling circuit and a high-voltage sampling circuit, the bus dynamic switching sampling circuit is electrically connected with the logic board and the power board and used for switching AMP monitoring pulses or alternating current pulses injected by the power board under the control of the logic board, and the high-voltage sampling circuit is electrically connected with the IT system and used for sampling insulation monitoring signals of the IT system; the logic board is also electrically connected with the bus dynamic switching sampling circuit, and is used for sending a pulse switching control signal to the bus dynamic switching sampling circuit, and is used for measuring and calculating an insulation monitoring signal after AMP monitoring pulse injection and an insulation monitoring signal after AC pulse insertion. The technical problem that an existing AMP measurement method is too long in monitoring time can be solved.

Description

Technical Field

[0001] This application relates to the field of power distribution system technology, and more particularly to an insulation monitoring device for an IT system. Background Technology

[0002] An IT system is a low-voltage power distribution system with a neutral point that is either ungrounded or grounded via high impedance. It is suitable for locations where high power supply continuity is required. The IT system has no direct electrical connection to the ground, or is only connected via high impedance (such as an arc suppression coil or resistor). Because it has no direct connection to the ground, when the equipment casing of the IT system leaks current, the IT system will not form a leakage current loop with the ground, thus protecting personnel safety to a certain extent.

[0003] Because IT systems do not form leakage circuits, commonly used residual current circuit breakers (RCCBs) are insufficient for monitoring leakage current in IT systems. Existing technologies typically employ insulation monitoring devices or fault location devices to monitor leakage faults in IT systems. Common insulation monitoring or fault location devices are usually based on the adaptive multi-parameter measurement (AMP) method for insulation monitoring of IT systems. The AMP method is a technique that improves the accuracy and anti-interference capability of insulation fault detection by dynamically injecting specific frequency AC test signals (such as low-frequency or high-frequency signals) into the IT system and measuring its impedance response to ground. The AMP method avoids power frequency harmonics, reducing false alarms. Furthermore, the AMP method can adaptively adjust test parameters, automatically optimizing them based on the system's capacitance to ground (such as changes in cable length), offering high sensitivity and the ability to detect minute insulation attenuations.

[0004] Although the traditional AMP measurement method has many advantages, it requires adaptive adjustment of test parameters based on the capacitance of the IT system being tested, dynamic injection of AC test signals in a specific frequency band, and multi-band analysis, which results in excessively long monitoring time and makes it unsuitable for scenarios with extremely high real-time requirements.

[0005] The above content is only used to help understand the technical solution of this application and does not represent an admission that the above content is prior art. Utility Model Content

[0006] The main purpose of this application is to provide an insulation monitoring device for IT systems, which aims to solve the technical problem of the existing AMP measurement method, which requires adaptive adjustment of test parameters according to the capacitance of the IT system and dynamic injection of AC test signals in a specific frequency band, resulting in excessively long monitoring time and making it unsuitable for scenarios with extremely high real-time requirements.

[0007] This application provides an insulation monitoring device for an IT system, comprising:

[0008] Power supply board, sampling board, and logic board; among them,

[0009] The power board is electrically connected to the IT system and is used to inject AMP monitoring pulses or AC pulses into the IT system;

[0010] The sampling board includes a bus dynamic switching sampling circuit and a high voltage sampling circuit. The bus dynamic switching sampling circuit is electrically connected to the logic board and the power board respectively, and is used to switch the AMP monitoring pulse or AC pulse injected by the power board under the control of the logic board. The high voltage sampling circuit is electrically connected to the IT system and is used to sample the insulation monitoring signal of the IT system.

[0011] The logic board is also electrically connected to the bus dynamic switching sampling circuit, used to send pulse switching control signals to the bus dynamic switching sampling circuit, and to calculate the insulation monitoring signal after injecting AMP monitoring pulses using the AMP measurement method, as well as to calculate the insulation monitoring signal after inserting AC pulses.

[0012] Preferably, in the above-mentioned insulation monitoring device, the power supply board includes:

[0013] The circuit includes a pulse injection circuit, a monitoring power supply circuit, a chip power supply circuit, and a logic power supply circuit; among which,

[0014] The pulse injection circuit is electrically connected to the bus dynamic switching sampling circuit and the IT system respectively, and is used to inject AMP monitoring pulses or AC pulses into the IT system under the control of the bus dynamic switching sampling circuit.

[0015] The monitoring power supply circuit is electrically connected to the sampling board and is used to power the sampling board.

[0016] The chip power supply circuit is used to feed back the insulation monitoring signal to the logic board;

[0017] The logic power supply circuit is used to power the logic board.

[0018] Preferably, in the above-mentioned insulation monitoring device, the bus dynamic switching sampling circuit is also electrically connected to the high-voltage sampling circuit and is also used to perform hardware sampling on the insulation monitoring signal collected by the high-voltage sampling circuit.

[0019] The aforementioned sampling board also includes a sampling microcontroller electrically connected to the bus dynamic switching sampling circuit and the logic board, which is used to perform sine filtering on the insulation monitoring signal after hardware sampling and send the sine-filtered insulation monitoring signal to the logic board.

[0020] Preferably, in the above-mentioned insulation monitoring device, the logic board includes:

[0021] The circuit includes a display operation circuit, an information storage circuit, a power output circuit, and an MCU circuit; among which,

[0022] The display operation circuit is electrically connected to both the external display operation module and the MCU circuit, and is used to display the calculation results of the MCU circuit and receive operation commands from the external display operation module.

[0023] The information storage circuit is electrically connected to the display operation circuit and the MCU circuit respectively, and is used to store operation instructions and calculation results;

[0024] The power output circuit is electrically connected to the power board and is used to control the power supply function of the power board.

[0025] The MCU circuit is electrically connected to the sampling board and is used to send pulse switching control signals to the sampling board, as well as to calculate the insulation monitoring signal after injecting AMP monitoring pulses and the insulation monitoring signal after inserting AC pulses using the AMP measurement method.

[0026] Preferably, in the above-mentioned insulation monitoring device, the MCU circuit includes:

[0027] The circuit includes a switching control subcircuit, a monitoring pulse filtering subcircuit, an AC pulse filtering subcircuit, and a data measurement subcircuit; among which,

[0028] The switching control sub-circuit is electrically connected to the bus dynamic switching sampling circuit and is used to send pulse switching control signals to the bus dynamic switching sampling circuit. The pulse switching control signals are used to control the bus dynamic switching sampling circuit and the AMP monitoring pulses or AC pulses injected by the switching power board.

[0029] The monitoring pulse filtering sub-circuit is electrically connected to the bus dynamic switching sampling circuit, and is used to perform Fourier transform filtering on the insulation monitoring signal after the AMP monitoring pulse is injected;

[0030] The AC pulse filtering sub-circuit is electrically connected to the bus dynamic switching sampling circuit and is used to filter the insulation monitoring signal after the AC pulse is inserted;

[0031] The data calculation sub-circuit is electrically connected to the monitoring pulse filter sub-circuit and the AC pulse filter sub-circuit respectively, and is used to calculate the filtered insulation monitoring signal.

[0032] Preferably, in the above-mentioned insulation monitoring device, the power board further includes an interface circuit electrically connected to the MCU circuit, the interface circuit including:

[0033] The fault relay control circuit, the early warning relay control circuit, the input / output circuit, and the communication output circuit are electrically connected to the logic board respectively; among them,

[0034] The communication output circuit is electrically connected to the MCU circuit and is used to output fault alarm information to the outside when the MCU circuit detects an abnormal insulation monitoring signal.

[0035] Preferably, in the above-mentioned insulation monitoring device, the logic board further includes a power interference compensation circuit electrically connected to the power board, used to assess the electromagnetic interference situation of the power board; the power interference compensation circuit includes:

[0036] The circuit includes a sampling subcircuit, a filter evaluation subcircuit, and a power quality evaluation subcircuit; among which,

[0037] The sampling sub-circuit is electrically connected to the power board and is used to perform AD sampling on the power supply voltage of the corresponding power supply in the power board to obtain the power supply sampling packet;

[0038] The filtering evaluation sub-circuit is electrically connected to the sampling sub-circuit and is used to evaluate the waveform of the power supply sampling packet using the insulation monitoring signal filtered by the MCU circuit.

[0039] The sampling sub-circuit is also used to drop the power sampling packet when the filtering evaluation sub-circuit evaluates the waveform of the power sampling packet as abnormal.

[0040] The power quality assessment sub-circuit is electrically connected to the sampling sub-circuit and is used to calculate the packet loss rate of the corresponding power supply and evaluate the power quality of the corresponding power supply according to the packet loss rate.

[0041] Preferably, in the above-mentioned insulation monitoring device, the MCU circuit further includes an interrupt control sub-circuit; the interrupt control sub-circuit is electrically connected to the data calculation sub-circuit and is used to periodically interrupt the AMP monitoring process of the insulation monitoring signal by the data calculation sub-circuit, and to perform AC pulse monitoring of the insulation monitoring signal.

[0042] Preferably, in the above-mentioned insulation monitoring device, the high-voltage sampling circuit includes a distributed capacitance sampling sub-circuit for sampling the distributed capacitance value of the IT system;

[0043] The MCU circuit also includes an AC pulse frequency setting sub-circuit, which is electrically connected to the distributed capacitance sampling sub-circuit and the bus dynamic switching sampling circuit, respectively. It is used to extend the injection frequency of the AC pulse through the bus dynamic switching sampling circuit when the distributed capacitance value is detected to be greater than or equal to a predetermined capacitance threshold.

[0044] Preferably, the above-mentioned insulation monitoring device further includes: an insulation protection circuit electrically connected to the IT system; the insulation protection circuit is also electrically connected to the logic board, and is used to provide insulation protection for the IT system when the logic board detects an abnormal insulation monitoring signal.

[0045] Preferably, the above-mentioned insulation monitoring device further includes a device housing, a status indicator and operation buttons fixed to the device housing; wherein,

[0046] The status indicator is electrically connected to the display operation circuit and is used to display the calculation results of the MCU circuit and the working status of the insulation monitoring device.

[0047] The operation buttons are electrically connected to the display operation circuit and are used to send operation commands to the display operation circuit.

[0048] The insulation monitoring device for the IT system proposed in this application has the following specific process:

[0049] The insulation monitoring device includes a power board, a sampling board, and a logic board. The power board is electrically connected to the IT system, and the sampling board includes a bus dynamic switching sampling circuit and a high-voltage sampling circuit. Specifically, the logic board sends a pulse switching control signal to the bus dynamic switching sampling circuit. Under the control of this pulse switching control signal, the bus dynamic switching sampling circuit cross-switches the power board to inject AMP monitoring pulses or AC pulses into the IT system. The high-voltage sampling circuit is electrically connected to the IT system, thus enabling real-time acquisition of the IT system's insulation monitoring signals. The logic board can calculate the insulation monitoring signal after the injection of AMP monitoring pulses and the insulation monitoring signal after the insertion of AC pulses. Because the insulation monitoring signal is obtained under the condition of injecting AMP monitoring pulses or AC pulses, the waveform of the insulation monitoring signal is correlated with the AMP monitoring pulses or AC pulses. When an insulation fault occurs in the IT system, the insulation monitoring signals caused by the AMP monitoring pulses and the insulation monitoring signals caused by the AC pulses will show waveform anomalies.

[0050] The technical solution provided in this application combines the advantages of AMP measurement and AC pulse measurement. By intermittently switching between injecting AMP monitoring pulses or AC pulses into the IT system, the insulation monitoring signal fed back by the IT system is periodically calculated using either AMP or AC pulse measurement. When the number of AC pulses reaches the calculation requirement, the calculation result can be output, thereby reducing the long cycle disadvantage of AMP detection and solving the problem that the traditional AMP measurement method has too long a monitoring time and is not suitable for scenarios with high real-time requirements, thus meeting the real-time measurement requirements. Furthermore, it retains the advantages of AMP measurement method, which automatically optimizes test parameters, has high sensitivity, and can detect minute insulation attenuation. Attached Figure Description

[0051] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0052] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0053] Figure 1A schematic diagram of the structure of an insulation monitoring device for a first type of IT system provided in this application embodiment;

[0054] Figure 2 This is a schematic diagram of the external structure of the insulation monitoring device for a second type of IT system provided in the embodiments of this application;

[0055] Figure 3 A schematic diagram of the structure of the insulation monitoring device for a third type of IT system provided in this application embodiment;

[0056] Figure 4 for Figure 2 The illustrated embodiment provides a schematic diagram of the structure of an MCU circuit;

[0057] Figure 5 This is a schematic diagram of the structure of a power supply interference compensation circuit provided in an embodiment of this application;

[0058] Figure 6 yes Figure 1 The illustrated embodiment provides an external structural diagram of an insulation monitoring device for an IT system.

[0059] Figure 7 This is a schematic diagram illustrating the principle of pulse signal insertion and monitoring provided in an embodiment of this application.

[0060] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings.

[0061] The relevant figures are labeled as follows:

[0062] 1-Power supply board, 2-Sampling board, 3-Logic board, 4-IT system, 5-External display and operation module, 6-Device casing, 7-Insulation protection circuit, 101-Pulse injection circuit, 102-Monitoring power supply circuit, 103-Chip power supply circuit, 104-Logic power supply circuit, 105-Interface circuit, 1051-Fault relay control circuit, 1052-Early warning relay control circuit, 1053-Input / output circuit, 1054-Communication output circuit, 201-Bus dynamic switching sampling circuit, 202-High voltage sampling circuit, 2021-Distributed capacitance sampling sub-circuit, 203-Sampling microcontroller, 301-Display and operation circuit, 302-Information storage circuit, 303-Power output circuit. 304-MCU circuit, 3041-Switching control sub-circuit, 3042-Monitoring pulse filtering sub-circuit, 3043-AC pulse filtering sub-circuit, 3044-Data calculation sub-circuit, 3045-AC pulse frequency setting sub-circuit, 305-Power interference compensation circuit, 3051-Sampling sub-circuit, 3052-Filter evaluation sub-circuit, 3053-Power quality evaluation sub-circuit, 501-Status indicator, 5011-Fault indicator, 5012-Warning indicator, 5013-Run indicator, 5014-Display screen, 502-Operation buttons, 5021-Setting buttons, 5022-Reset buttons, 5023-Test buttons, 503-Fixing holes, 504-Terminal blocks. Detailed Implementation

[0063] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0064] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0065] The existing technology has the following technical problems:

[0066] Existing insulation monitoring or fault location devices for monitoring leakage current faults in IT systems typically rely on the adaptive multi-parameter measurement (AMP) method. The AMP method improves the accuracy and interference resistance of insulation fault detection by dynamically injecting specific frequency AC test signals (such as low or high frequencies) into the IT system and measuring its impedance response to ground. However, because the AMP method requires adaptive adjustment of test parameters based on the capacitance of the IT system being tested, dynamically injecting specific frequency AC test signals, and performing multi-frequency analysis, the monitoring time is excessively long, making it unsuitable for scenarios with extremely high real-time requirements.

[0067] To address the aforementioned technical problems, the following embodiments of this application provide a solution. By switching between injecting AMP monitoring pulses or AC pulses into the IT system 4 and maintaining real-time sampling of the IT system 4, the insulation monitoring signal of the IT system 4 is sampled. Then, in the traditional AMP measurement method, the insulation monitoring signal after inserting AC pulses is calculated. In this way, when the number of AC pulses reaches the calculation requirement, the calculation result can be output, greatly reducing the long cycle disadvantage of AMP detection. This solves the problem that the traditional AMP measurement method has too long a monitoring time and is not suitable for scenarios with high real-time requirements, thereby improving the accuracy and stability of the AMP measurement method and enabling timely response to sudden insulation faults.

[0068] To better understand the above technical solutions, exemplary embodiments of this application will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of this application are shown in the drawings, it should be understood that this application can be implemented in various forms and should not be limited to the embodiments shown herein. Rather, these embodiments are provided so that this application can be thoroughly understood and its scope can be fully conveyed to those skilled in the art.

[0069] To achieve the above technical objectives, see [link to relevant documentation]. Figures 1 to 3 , Figure 1 This application provides a schematic flowchart of an insulation monitoring device for an IT system. Figure 1 As shown, the insulation monitoring device of this IT system includes:

[0070] Power board 1, sampling board 2, and logic board 3;

[0071] Among them, such as Figure 2 As shown, power board 1 is electrically connected to IT system 4 and is used to inject AMP monitoring pulses or AC pulses into IT system 4. AMP monitoring pulses are AC test signals of a specific frequency band, either low or high, suitable for the AMP measurement method of IT system 4; while AC pulses are fixed-frequency signals suitable for the AC injection method. The structure of the IT system to be measured is as follows: Figure 3 As shown, it includes the current loop formed by the DC bus and the ground.

[0072] like Figure 2As shown, sampling board 2 includes a bus dynamic switching sampling circuit 201 and a high-voltage sampling circuit 202. The bus dynamic switching sampling circuit 201 is electrically connected to logic board 3 and power board 1, respectively, and is used to switch between AMP monitoring pulses or AC pulses injected by power board 1 under the control of logic board 3. The high-voltage sampling circuit 202 is electrically connected to IT system 4 and is used to sample the insulation monitoring signal of IT system 4. The bus dynamic switching sampling circuit 201 is used to control the pulse injection circuit 101 to inject pulses into IT system 4, and to switch between the AMP monitoring pulses or AC pulses to be injected under the control of logic board 3. The DC bus of IT system 4 forms an AC loop with the ground. When AMP monitoring pulses or AC pulses are injected, this loop will produce a change in its ground impedance response. This ground impedance response can reflect the insulation performance of IT system 4, i.e., the aforementioned insulation monitoring signal of IT system 4. Here, the ground impedance response to be measured for the insulation monitoring signal includes distributed capacitance or insulation resistance, etc.

[0073] like Figure 2 As shown, logic board 3 is also electrically connected to bus dynamic switching sampling circuit 201, used to send pulse switching control signals to bus dynamic switching sampling circuit 201, and to calculate the insulation monitoring signal after injecting AMP monitoring pulses using the AMP measurement method, and to calculate the insulation monitoring signal after inserting AC pulses. By sending pulse switching control signals to bus dynamic switching sampling circuit 201, logic board 3 can control pulse injection circuit 101 to inject AMP monitoring pulses into IT system 4, or inject AC pulses into IT system 4, through bus dynamic switching sampling circuit 201. Under the influence of two types of pulses, IT system 4 generates insulation monitoring signals, which include ground impedance responses such as distributed capacitance and insulation resistance values. These ground impedance responses are collected by high-voltage sampling circuit 202 and fed back to logic board 3. When IT system 4 has slight insulation attenuation, these ground impedance responses will produce waveform changes. Logic board 3 uses the AMP measurement method to calculate the insulation monitoring signal and also calculates the insulation monitoring signal after inserting AC pulses. It can combine the advantages of the AMP measurement method and the AC pulse measurement method. When the number of AC pulses reaches the calculation requirements, the calculation results can be output, solving the problem that the traditional single use of the AMP measurement method leads to excessively long monitoring time and is not suitable for scenarios with high timeliness requirements.

[0074] In summary, the technical solution provided in this application combines the advantages of AMP measurement and AC pulse measurement. By intermittently switching between injecting AMP monitoring pulses or AC pulses into the IT system 4, the insulation monitoring signal fed back by the IT system 4 is periodically measured using either the AMP measurement method or the AC pulse measurement method. When the number of AC pulses reaches the calculation requirement, the calculation result can be output, thereby reducing the long cycle disadvantage of AMP detection and solving the problem that the traditional AMP measurement method has too long a monitoring time and is not suitable for scenarios with high real-time requirements, thus meeting the real-time measurement requirements. Furthermore, it retains the advantages of the AMP measurement method, which automatically optimizes test parameters, has high sensitivity, and can detect minute insulation attenuation.

[0075] In one preferred embodiment, such as Figure 2 As shown, in the above-mentioned insulation monitoring device, the power supply board 1 includes:

[0076] The circuit includes a pulse injection circuit 101, a monitoring power supply circuit 102, a chip power supply circuit 103, and a logic power supply circuit 104; among which,

[0077] The pulse injection circuit 101 is electrically connected to both the bus dynamic switching sampling circuit 201 and the IT system 4, and is used to interleave the injection of AMP monitoring pulses or AC pulses into the IT system 4 under the control of the bus dynamic switching sampling circuit 201; for example Figure 2 As shown, the pulse injection circuit 101 in this embodiment of the application is preferably a -50V to +50V pulse power supply circuit.

[0078] The monitoring power supply circuit 102 is electrically connected to the sampling board 2 and is used to supply power to the sampling board 2; for example Figure 2 As shown, the monitoring power supply circuit 102 of this application is preferably a -12V to +12V monitoring power supply circuit 102.

[0079] The chip power supply circuit 103 is used to feed back the insulation monitoring signal to the logic board 3; for example... Figure 2 As shown, the chip power supply circuit 103 of this application is preferably an AD chip 5V power supply circuit.

[0080] The logic power supply circuit 104 is used to power the logic board 3. For example... Figure 2 As shown, the logic power supply circuit 104 of this application is preferably a 5V logic power supply circuit.

[0081] The technical solution provided in this application embodiment allows the pulse injection circuit 101, under the control of the bus dynamic switching sampling circuit 201, to inject AMP monitoring pulses or AC pulses into the IT system 4. This causes the IT system 4 to feed back different insulation monitoring signals, enabling the logic board 3 to quickly monitor for insulation attenuation in the IT system 4 using a combination of AMP measurement and AC injection methods. The monitoring power supply circuit 102 is electrically connected to the sampling board 2 and provides power to it. Specifically, it is electrically connected to the bus dynamic switching sampling circuit 201, which powers the entire sampling board 2.

[0082] In one preferred embodiment, such as Figure 2 As shown, in the above insulation monitoring device, the bus dynamic switching sampling circuit 201 is also electrically connected to the high voltage sampling circuit 202, and is also used to perform hardware sampling on the insulation monitoring signal collected by the high voltage sampling circuit 202.

[0083] The aforementioned sampling board 2 further includes a sampling microcontroller 203 electrically connected to the bus dynamic switching sampling circuit 201 and the logic board 3, respectively. This microcontroller performs sinusoidal filtering on the hardware-sampled insulation monitoring signal and sends the sinusoidally filtered insulation monitoring signal to the logic board 3. In this embodiment, the sampling microcontroller 203 is preferably an AUC845BSZ62 sampling microcontroller 203. The sampling microcontroller 203 is mainly used for sampling and sinusoidal filtering. Then, the sampling result, i.e., the aforementioned insulation monitoring signal, is sent to the MCU circuit 304 of the logic board 3 via a serial port. The MCU circuit 304 of the logic board 3 performs Fourier transform filtering, value acquisition, and control cross-injection on the insulation monitoring signal.

[0084] The ADUC845BSZ62 sampling microcontroller 203 is used to perform sinusoidal filtering on the insulation monitoring signal and, in conjunction with logic board 3, controls the injection of a specific frequency. The filtered and injected insulation monitoring signal is then fed back to the MCU circuit 304 on logic board 3. It should be noted that the insulation monitoring signal is a series of sampled voltage values, which contain various waveform components, including the voltage waveform fed back after AMP injection, interference waveforms, and waveforms from indirect AC injection. Filtering and algorithms are needed to filter these waveforms to obtain the desired feedback result.

[0085] In the technical solution provided in this application embodiment, the bus dynamic switching sampling circuit 201 is electrically connected to the high-voltage sampling circuit 202. The high-voltage sampling circuit 202 has a hardware sampling function for the insulation monitoring signal acquired by the insulation monitoring signal. This hardware sampling function involves performing a series of step-down filtering operations on the insulation monitoring signal before it enters the sampling microcontroller 203. The sampling microcontroller 203 can perform sine wave filtering on the insulation monitoring signal, filtering out the sine wave and reducing signal interference. After sine wave filtering, the sampling microcontroller 203 sends the insulation monitoring signal to the logic board 3. Through the above method, signal interference of the insulation monitoring signal can be reduced, and the processing efficiency of the insulation monitoring signal by the logic board 3 can be improved.

[0086] In one preferred embodiment, such as Figure 2 As shown, in the above-mentioned insulation monitoring device, the logic board 3 includes:

[0087] The circuit includes a display operation circuit 301, an information storage circuit 302, a power output circuit 303, and an MCU circuit 304; among which,

[0088] The display operation circuit 301 is electrically connected to the external display operation module 5 and the MCU circuit 304 respectively, and is used to display the calculation results of the MCU circuit 304 and receive the operation instructions of the external display operation module 5.

[0089] The information storage circuit 302 is electrically connected to the display operation circuit 301 and the MCU circuit 304 respectively, and is used to store operation instructions and calculation results;

[0090] The power output circuit 303 is electrically connected to the power board 1 and is used to control the power supply function of the power board 1.

[0091] The MCU circuit 304 is electrically connected to the sampling board 2 and is used to send pulse switching control signals to the sampling board 2, as well as to use the AMP measurement method to measure the insulation monitoring signal after injecting AMP monitoring pulses and to measure the insulation monitoring signal after inserting AC pulses.

[0092] The MCU circuit 304 on logic board 3 performs Fourier transform filtering using the AMP algorithm to calculate the insulation result. During the calculation process, the AMP algorithm is interrupted, and AC pulses are injected. Multiple interrupted AC injection pulses are then calculated, thus achieving compatibility between the AMP method and the AC injection method. The AMP algorithm is interrupted during or after the insulation result calculation, ensuring a gap between the previous AMP frequency injection and the next.

[0093] In the technical solution provided in this application embodiment, the external display operation module 5 sends an operation command to the display operation circuit 301. The display operation circuit 301 sends the operation command to the information storage circuit 302 for storage and feeds it back to the MCU circuit 304. According to the operation command, the MCU circuit 304 sends a pulse switching control signal to the sampling board 2, and simultaneously collects and calculates the above-mentioned insulation monitoring signal to obtain the calculation result. When the MCU circuit 304 obtains the calculation result, it stores the calculation result in the information storage circuit 302 and simultaneously feeds the calculation result back to the display operation circuit 301 for display. In addition, the power output circuit 303 is electrically connected to the power board 1 and can be used to control the power supply function of the power board 1. Through the above structure, real-time measurement of the ground impedance response of the IT system 4 can be realized, improving the calculation efficiency of the insulation performance of the IT system 4.

[0094] In addition, as a preferred embodiment, such as Figure 4 As shown, in the above-mentioned insulation monitoring device, the MCU circuit 304 includes:

[0095] The circuit includes a switching control subcircuit 3041, a monitoring pulse filtering subcircuit 3042, an AC pulse filtering subcircuit 3043, and a data measurement subcircuit 3044; among which...

[0096] The switching control sub-circuit 3041 is electrically connected to the bus dynamic switching sampling circuit 201 and is used to send a pulse switching control signal to the bus dynamic switching sampling circuit 201. The pulse switching control signal is used to control the bus dynamic switching sampling circuit 201 to switch between injected AMP monitoring pulses or AC pulses.

[0097] The monitoring pulse filtering sub-circuit 3042 is electrically connected to the bus dynamic switching sampling circuit 201 and is used to perform Fourier transform filtering on the insulation monitoring signal after the AMP monitoring pulse is injected.

[0098] The AC pulse filter sub-circuit 3043 is electrically connected to the bus dynamic switching sampling circuit 201 and is used to filter the insulation monitoring signal after the AC pulse is inserted.

[0099] The data calculation sub-circuit 3044 is electrically connected to the monitoring pulse filter sub-circuit 3042 and the AC pulse filter sub-circuit 3043 respectively, and is used to calculate the filtered insulation monitoring signal.

[0100] The technical solution provided in this application embodiment, through the switching control sub-circuit 3041 electrically connected to the bus dynamic switching sampling circuit 201, can control the bus dynamic switching sampling circuit 201 via a pulse switching control signal. The bus dynamic switching sampling circuit 201 can switch between injecting AMP monitoring pulses or AC pulses into the IT system 4. Then, the high-voltage sampling circuit 202 can collect the insulation monitoring signal generated after the injection pulse. Since the insulation monitoring signal is generated by injecting AMP monitoring pulses or AC pulses respectively, the monitoring pulse filtering sub-circuit and the AC pulse filtering sub-circuit can be used to perform Fourier transform filtering on the insulation monitoring signal after injecting AMP monitoring pulses and filtering on the insulation monitoring signal after inserting AC pulses, respectively. Finally, the data calculation sub-circuit can calculate the filtered insulation monitoring signal to determine whether there is insulation performance degradation in the IT system 4. In addition, as Figure 7 As shown, AC pulses are inserted intermittently between the AMP monitoring pulses. By measuring multiple AC pulses, two things can be achieved: first, accurate identification of the AC-injected waveform frequency band can be ensured; second, the accuracy and stability of multi-point measurements can be improved. Here, the insulation monitoring signal is specifically measured by calculating the insulation resistance value.

[0101] In addition, as a preferred embodiment, such as Figure 2 As shown, in the above-mentioned insulation monitoring device, the power board 1 further includes an interface circuit 105 electrically connected to the MCU circuit 304. The interface circuit 105 includes:

[0102] The fault relay control circuit 1051, the early warning relay control circuit 1052, the input / output circuit 1053, and the communication output circuit 1054 are electrically connected to the logic board 3, respectively; among them,

[0103] The communication output circuit 1054 is electrically connected to the MCU circuit 304 and is used to output fault alarm information to the outside when the MCU circuit 304 detects an abnormality in the insulation monitoring signal. The communication output circuit 1054 can be either a CAN circuit or an RS485 circuit.

[0104] The technical solution provided in this application embodiment includes a fault relay control circuit 1051, a warning relay control circuit 1052, an input / output circuit 1053, and a communication output circuit 1054, which can provide external functional access for related relays, communication, fault display, and other functions. When the MCU circuit 304 detects an abnormal insulation monitoring signal, the communication output circuit 1054 outputs fault alarm information to the outside, enabling relevant technicians to promptly obtain and handle insulation faults in the IT system 4.

[0105] The monitoring power supply circuit 102 that supplies power to the sampling board 2 is susceptible to electromagnetic interference, which can affect the sampling performance of the sampling board 2. To address this issue, as a preferred embodiment, such as... Figure 3 As shown, in the above-mentioned insulation monitoring device, the logic board 3 also includes a power interference compensation circuit 305 electrically connected to the power board 1, used to evaluate the electromagnetic interference situation of the power board 1; see also Figure 6 The power supply interference compensation circuit 305 includes:

[0106] Sampling sub-circuit 3051, filter evaluation sub-circuit 3052, and power quality evaluation sub-circuit 3053; among which,

[0107] The sampling sub-circuit 3051 is electrically connected to the power board 1 and is used to perform AD sampling on the power supply voltage of the corresponding power supply in the power board 1 to obtain the power supply sampling packet.

[0108] The filtering evaluation sub-circuit 3052 is electrically connected to the sampling sub-circuit 3051 and is used to evaluate the waveform of the power supply sampling packet using the insulation monitoring signal filtered by the MCU circuit 304.

[0109] The sampling sub-circuit 3051 is also used to drop the power sampling packet when the filtering evaluation sub-circuit 3052 evaluates the waveform of the power sampling packet as abnormal.

[0110] The power quality assessment sub-circuit 3053 is electrically connected to the sampling sub-circuit 3051 and is used to calculate the packet loss rate of the corresponding power supply and evaluate the power quality of the corresponding power supply according to the packet loss rate.

[0111] The technical solution provided in this application embodiment includes setting up power supply electromagnetic interference (EMI) compensation. When the sampling sub-circuit 3051 detects the 24V system power supply (i.e., Figure 2 When the -12V to +12V monitoring power supply circuit 102 is subjected to electromagnetic interference, the filtering evaluation sub-circuit 3052 uses a filtering algorithm to evaluate the power supply status sampled by the AD converter. If the evaluated AD value segment is determined to be severely interfered with, the sampling end will perform a packet loss operation. Simultaneously, the system settings interface displays the system's sampling packet loss rate, i.e., the proportion of discarded sampling packets out of all sampling packets within a certain period, thus evaluating the system's power quality. It should be noted that the interference in the AD value is mainly determined by the algorithm to determine whether it conforms to the waveform after filtering using the AMP and AC injection methods. If the amplitude fluctuation of the obtained waveform data is abnormal, resulting in unreliable data, a packet loss operation will be performed. Then, the next set of sampled data is analyzed; if the packet loss rate is too high, it indicates excessive power supply interference.

[0112] In addition, as a preferred embodiment, the MCU circuit 304 in the above-mentioned insulation monitoring device further includes an interrupt control sub-circuit; the interrupt control sub-circuit is electrically connected to the data calculation sub-circuit and is used to periodically interrupt the AMP monitoring process of the insulation monitoring signal by the data calculation sub-circuit to perform AC pulse monitoring of the insulation monitoring signal.

[0113] Combination Figure 7 As shown in the schematic diagram of the pulse monitoring principle, the technical solution provided in this application interrupts the original fixed long-cycle AMP monitoring process and inserts an AC pulse monitoring process, thereby realizing the measurement of AC pulses. After the AMP monitoring process is interrupted, the computing resources are handed over to the AC pulse monitoring process, and the current continuous calculation results are provided to the AC pulse monitoring process, thereby improving the monitoring efficiency of the insulation performance of the IT system. AMP monitoring continues after the AC pulse monitoring ends.

[0114] pass Figure 7 As illustrated by the pulse monitoring principle, by combining AMP with AC pulse injection, the detection process is interrupted during the AMP detection cycle and pulse transmission cycle, and the detection state is maintained. At this time, an AC pulse method is inserted, inserting an AC detection pulse, and then returning to AMP detection. When the number of AC pulses reaches the calculation requirement, the result is output, greatly reducing the long cycle drawback of AMP detection and improving the accuracy and stability of the AMP method. Meanwhile, AC pulse injection enables a rapid response to sudden insulation faults.

[0115] Furthermore, the traditional AMP measurement method is capacitance sensitive to IT systems 4. While the traditional AMP method can adapt to certain variations in capacitance to ground, signal attenuation in extremely high-capacitance systems (such as long cable networks) leads to a decrease in measurement accuracy. To address the above technical problems, as a preferred embodiment, such as... Figure 2 As shown, in the above-mentioned insulation monitoring device, the high-voltage sampling circuit 202 includes a distributed capacitance sampling sub-circuit 2021, which is used to sample the distributed capacitance value of the IT system 4.

[0116] The MCU circuit 304 also includes an AC pulse frequency setting sub-circuit 3045, which is electrically connected to the distributed capacitance sampling sub-circuit 2021 and the bus dynamic switching sampling circuit 201, respectively. When the distributed capacitance value is detected to be greater than or equal to a predetermined capacitance threshold, the AC pulse injection frequency is extended by the bus dynamic switching sampling circuit 201.

[0117] The technical solution provided in this application embodiment can reduce the capacitance sensitivity of the traditional AMP measurement method to the IT system 4 by setting the AC pulse frequency setting sub-circuit 3045. The AC injection method is used to extend the AC injection frequency according to the distributed capacitance detected on site, so as to meet the operating conditions of large distributed capacitance.

[0118] Furthermore, if the insulation performance of IT system 4 deteriorates, or even if a leakage current loop forms between the equipment casing and the ground, it will affect the safety of operators. To solve the above technical problems, as a preferred embodiment, such as... Figure 2 As shown, the above-mentioned insulation monitoring device also includes:

[0119] An insulation protection circuit 7 is electrically connected to the IT system 4; the insulation protection circuit 7 is also electrically connected to the logic board 3, and is used to provide insulation protection for the IT system 4 when the logic board 3 detects an abnormal insulation monitoring signal.

[0120] By setting up the insulation protection circuit 7, the IT system 4 can be insulated and protected, reducing the possibility of leakage current from the equipment casing and the formation of a leakage circuit. The insulation protection circuit 7 can be a high-impedance resistor or an insulating material.

[0121] In addition, as a preferred embodiment, such as Figure 6 As shown, the above-mentioned insulation monitoring device also includes a device housing 6, a status indicator 501 and an operation button 502 fixed to the device housing 6; wherein,

[0122] The status indicator 501 is electrically connected to the display operation circuit 301 and is used to display the calculation results of the MCU circuit 304 and the working status of the insulation monitoring device.

[0123] The operation button 502 is electrically connected to the display operation circuit 301 and is used to send operation commands to the display operation circuit 301.

[0124] like Figure 6 As shown, the status indicator 501 of this application includes a fault indicator 5011, a warning indicator 5012, a running indicator 5013, and a display screen 5014, etc.; the operation buttons 502 include a setting button 5021, a reset button 5022, and a test button 5023, etc. The status indicator lights can display the calculation results of the MCU circuit 304, i.e., the insulation status of the IT system 4, and indicate parameters such as the working performance status of the insulation monitoring device. The operation buttons 502 can receive user operation commands and control the display operation circuit 301 to execute the corresponding operation commands. In addition, the device housing 6 also includes structures such as fixing holes 503 and wiring terminals 504.

[0125] In addition, combined Figure 7As illustrated by the pulse signal insertion and monitoring principle, the AMP monitoring pulse is combined with AC pulse injection. Specifically, the detection process is interrupted during the AMP detection cycle and pulse transmission cycle while maintaining the detection state. At this time, AC detection pulses are inserted using the AC pulse method, returning the calculation results of the insulation monitoring signal from the AMP measurement method. Similarly, AC pulse detection returns the calculation results of the insulation monitoring signal caused by the AC pulse. When the number of AC pulses reaches the calculation requirement, the calculation results are output, significantly reducing the long cycle drawback of AMP detection and improving the accuracy and stability of the AMP method. Furthermore, AC pulse injection enables a rapid response to sudden insulation faults.

[0126] Compared with the prior art, this application has the following advantages and positive effects:

[0127] This application utilizes the AC injection method to shorten the monitoring time for the insulation performance of IT systems, thus enabling the detection of temporary emergency faults. The AMP method is used for real-time monitoring of insulation attenuation, and the EMI interference detection and compensation function eliminates the need for frequency conversion. This compensation function improves the power supply stability of the system. Combining the AMP method with the AC injection method, along with the EMI interference compensation function, overcomes the shortcomings of either the single AMP measurement method or the AC pulse measurement method.

[0128] In addition, it should be noted that the above examples are only for understanding this application and do not constitute a limitation on the feeding control technology solution of this application. Any simple modifications based on this technical concept are within the protection scope of this application.

[0129] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0130] It should also be noted that in some alternative implementations, the functions marked in the boxes may occur in a different order than those shown in the accompanying drawings. For example, two consecutively indicated boxes may actually be executed substantially in parallel, and sometimes they may be executed in reverse order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and combinations of boxes in the block diagram and / or flowchart, can be implemented using a dedicated hardware-based system that performs the specified functions or operations, or can be implemented using a combination of dedicated hardware and computer instructions.

[0131] The modules described in the embodiments of this application can be implemented in software or hardware. The names of the modules do not necessarily limit the functionality of the unit itself.

[0132] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.

Claims

1. An insulation monitoring device for an IT system, characterized in that, include: The power supply board (1), sampling board (2), and logic board (3) are included; among them, The power board (1) is electrically connected to the IT system (4) and is used to inject AMP monitoring pulses or AC pulses into the IT system (4); The sampling board (2) includes a bus dynamic switching sampling circuit (201) and a high voltage sampling circuit (202). The bus dynamic switching sampling circuit (201) is electrically connected to the logic board (3) and the power board (1) respectively, and is used to switch the AMP monitoring pulse or AC pulse injected by the power board (1) under the control of the logic board (3). The high voltage sampling circuit (202) is electrically connected to the IT system (4) and is used to sample the insulation monitoring signal of the IT system (4). The logic board (3) is also electrically connected to the bus dynamic switching sampling circuit (201) for sending pulse switching control signals to the bus dynamic switching sampling circuit (201) and for using the AMP measurement method to calculate the insulation monitoring signal after injecting AMP monitoring pulses and to calculate the insulation monitoring signal after inserting AC pulses.

2. The insulation monitoring device according to claim 1, characterized in that, The power board (1) includes: The circuit includes a pulse injection circuit (101), a monitoring power supply circuit (102), a chip power supply circuit (103), and a logic power supply circuit (104); among which, The pulse injection circuit (101) is electrically connected to the bus dynamic switching sampling circuit (201) and the IT system (4) respectively, and is used to inject AMP monitoring pulses or AC pulses into the IT system (4) under the control of the bus dynamic switching sampling circuit (201). The monitoring power supply circuit (102) is electrically connected to the sampling board (2) and is used to supply power to the sampling board (2); The chip power supply circuit (103) is used to feed back the insulation monitoring signal to the logic board (3); The logic power supply circuit (104) is used to supply power to the logic board (3).

3. The insulation monitoring device according to claim 1, characterized in that, The bus dynamic switching sampling circuit (201) is also electrically connected to the high voltage sampling circuit (202) and is also used to perform hardware sampling on the insulation monitoring signal collected by the high voltage sampling circuit (202); The sampling board (2) further includes a sampling microcontroller (203) electrically connected to the bus dynamic switching sampling circuit (201) and the logic board (3), respectively, for performing sine filtering on the insulation monitoring signal after hardware sampling, and sending the sine-filtered insulation monitoring signal to the logic board (3).

4. The insulation monitoring device according to claim 1, characterized in that, The logic board (3) includes: The circuit includes a display operation circuit (301), an information storage circuit (302), a power output circuit (303), and an MCU circuit (304); among which, The display operation circuit (301) is electrically connected to the external display operation module (5) and the MCU circuit (304) respectively, and is used to display the calculation results of the MCU circuit (304) through the external display operation module (5) and to receive the operation instructions of the external display operation module (5); The information storage circuit (302) is electrically connected to the display operation circuit (301) and the MCU circuit (304) respectively, and is used to store the operation instructions and the calculation results; The power output circuit (303) is electrically connected to the power board (1) and is used to control the power supply function of the power board (1); The MCU circuit (304) is electrically connected to the sampling board (2) and is used to send a pulse switching control signal to the sampling board (2), and to use the AMP measurement method to measure the insulation monitoring signal after injecting the AMP monitoring pulse and to measure the insulation monitoring signal after inserting the AC pulse.

5. The insulation monitoring device according to claim 4, characterized in that, The MCU circuit (304) includes: The circuit includes a switching control subcircuit (3041), a monitoring pulse filtering subcircuit (3042), an AC pulse filtering subcircuit (3043), and a data calculation subcircuit (3044); among which, The switching control sub-circuit (3041) is electrically connected to the bus dynamic switching sampling circuit (201) and is used to send a pulse switching control signal to the bus dynamic switching sampling circuit (201). The pulse switching control signal is used to control the bus dynamic switching sampling circuit (201) to switch the AMP monitoring pulse or AC pulse injected by the power board (1). The monitoring pulse filtering sub-circuit (3042) is electrically connected to the bus dynamic switching sampling circuit (201) and is used to perform Fourier transform filtering on the insulation monitoring signal after the AMP monitoring pulse is injected. The AC pulse filtering sub-circuit (3043) is electrically connected to the bus dynamic switching sampling circuit (201) and is used to filter the insulation monitoring signal after the AC pulse is inserted. The data calculation sub-circuit (3044) is electrically connected to the monitoring pulse filtering sub-circuit (3042) and the AC pulse filtering sub-circuit (3043) respectively, and is used to calculate the filtered insulation monitoring signal.

6. The insulation monitoring device according to claim 5, characterized in that, The power board (1) further includes an interface circuit (105) electrically connected to the MCU circuit (304), the interface circuit (105) including: The fault relay control circuit (1051), the early warning relay control circuit (1052), the input / output circuit (1053), and the communication output circuit (1054) are electrically connected to the logic board (3), respectively; wherein, The communication output circuit (1054) is electrically connected to the MCU circuit (304) and is used to output fault alarm information to the outside when the MCU circuit (304) detects that the insulation monitoring signal is abnormal.

7. The insulation monitoring device according to claim 5, characterized in that, The logic board (3) further includes a power interference compensation circuit (305) electrically connected to the power board (1) for evaluating the electromagnetic interference of the power board (1); the power interference compensation circuit (305) includes: The circuit includes a sampling sub-circuit (3051), a filter evaluation sub-circuit (3052), and a power quality evaluation sub-circuit (3053); among which, The sampling sub-circuit (3051) is electrically connected to the power board (1) and is used to perform AD sampling on the power supply voltage of the corresponding power supply in the power board (1) to obtain a power sampling packet; The filtering evaluation sub-circuit (3052) is electrically connected to the sampling sub-circuit (3051) and is used to evaluate the waveform of the power sampling packet using the insulation monitoring signal filtered by the MCU circuit (304). The sampling sub-circuit (3051) is also used to perform a packet dropping operation on the power sampling packet when the filtering evaluation sub-circuit (3052) evaluates that the waveform of the power sampling packet is abnormal. The power quality assessment sub-circuit (3053) is electrically connected to the sampling sub-circuit (3051) and is used to count the packet loss rate of the corresponding power supply and evaluate the power quality of the corresponding power supply according to the packet loss rate.

8. The insulation monitoring device according to claim 5, characterized in that, The high-voltage sampling circuit (202) includes a distributed capacitance sampling sub-circuit (2021) for sampling the distributed capacitance value of the IT system (4); The MCU circuit (304) further includes an AC pulse frequency setting sub-circuit (3045), which is electrically connected to the distributed capacitance sampling sub-circuit (2021) and the bus dynamic switching sampling circuit (201) respectively. When the distributed capacitance value collected by the distributed capacitance sampling sub-circuit (2021) is greater than or equal to a predetermined capacitance threshold, the bus dynamic switching sampling circuit (201) extends the injection frequency of the AC pulse.

9. The insulation monitoring device according to claim 4, characterized in that, The insulation monitoring device also includes: The device housing (6) includes an external display operation module (5) fixed to the device housing (6); the external display operation module (5) includes a status indicator (501) and operation buttons (502); The status indicator (501) is electrically connected to the display operation circuit (301) and is used to display the calculation results of the MCU circuit (304) and the working status of the insulation monitoring device; The operation button (502) is electrically connected to the display operation circuit (301) and is used to send operation commands to the display operation circuit (301).

10. The insulation monitoring device according to claim 1, characterized in that, The insulation monitoring device also includes: An insulation protection circuit (7) electrically connected to the IT system (4) is also electrically connected to the logic board (3) for providing insulation protection to the IT system (4) when the logic board (3) detects an abnormality in the insulation monitoring signal.

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