A multi-dimensional diagnosis method and system for signal sampling channels

Abstract

The present invention discloses a multi-dimensional diagnosis method and system for a signal sampling channel. When multiple voltage transformer groups are from the same voltage source, by calculating the sampling channel difference value and the three-phase imbalance difference value, if the sampling channel difference value and the three-phase imbalance difference value are greater than a preset value, the sampling channel is abnormal. If the multiple voltage transformer groups are not from the same voltage source, if the input voltage, output voltage and three-phase voltage suddenly change within a preset time, the sampling channel of the voltage transformer online monitoring device is judged to be abnormal. This method evaluates the signal sampling channel status of the voltage transformer online monitoring device from three dimensions: the same voltage and same phase sequence diagnosis method, the same voltage and different phase sequence diagnosis method, and the different voltage diagnosis method. It can effectively diagnose abnormal channels and improve the accuracy and reliability of data collected by the signal sampling channel.

Description

Technical Field

[0001] The present invention relates to the field of signal diagnosis technology, and in particular to a multi-dimensional diagnosis method and system for a signal sampling channel. Background Art

[0002] As a component of electric energy metering, the operational accuracy of voltage transformers (VTs) is of particular concern to power suppliers, transmitters, and consumers. Currently, VT error detection relies on offline testing during power outages, which cannot accurately assess the accuracy of VTs during operation. To monitor the accuracy of VT errors during operation, online VT metering performance monitoring devices have emerged. These devices collect the output signal from the metering winding of a VT during operation and employ an intelligent analysis model within them. Without a physical standard, they can calculate VT errors and provide metering performance status.

[0003] At present, the testing items of the voltage transformer metering performance online monitoring device include insulation performance and metering performance, all of which are completed in the laboratory and installed after passing the test. As a secondary power equipment, its own reliability during long-term operation will directly affect the evaluation results of its monitoring equipment. At present, after the voltage transformer metering performance online monitoring device is powered on and put into operation, there are no in-operation testing requirements, and the online monitoring device itself does not have the function of self-diagnosis of the sampling channel accuracy during operation. Therefore, after long-term operation, the accuracy of the sampling of each sampling channel itself is difficult to evaluate, which brings reliability risks to the error analysis results and metering performance evaluation of the monitored voltage transformer. Summary of the Invention

[0004] The present invention provides a multi-dimensional diagnosis method and system for signal sampling channels, which realizes the positioning of abnormal sampling channels from multi-dimensional perspectives and improves the accuracy and reliability of data collected by signal sampling channels.

[0005] In order to solve the above technical problems, an embodiment of the present invention provides a multi-dimensional diagnosis method for a signal sampling channel, comprising:

[0006] Identify whether multiple voltage transformer groups are the same voltage source;

[0007] When the multiple voltage transformer groups are the same voltage source, a first sub-sampling channel and a second sub-sampling channel in the voltage transformer group are used to collect voltage transformer signals to obtain a first voltage transformer signal and a second voltage transformer signal, so that the diagnostic system obtains a channel difference value according to the first voltage transformer signal and the second voltage transformer signal;

[0008] When the channel difference value is greater than a preset first threshold, it is determined that the sampling channel of the voltage transformer online monitoring device is abnormal, and the three-phase unbalance difference value of each voltage transformer group is calculated. When the three-phase unbalance difference value is greater than a preset second threshold, it is confirmed that the sampling channel of the voltage transformer group whose three-phase unbalance difference value is greater than the preset second threshold is abnormal;

[0009] When multiple voltage transformer groups are not from the same voltage source, the input voltage, output voltage and three-phase voltage of the substation within the preset time are collected. If the input voltage, output voltage and three-phase voltage do not change consistently within the preset time, it is determined whether the change trend is a sudden change. If it is a sudden change, it is determined that the sampling channel of the voltage transformer online monitoring device is abnormal.

[0010] In the embodiment of the present invention, by identifying whether multiple voltage sensor groups are the same voltage source, when multiple voltage transformer groups are the same voltage source, the first sub-sampling channel and the second sub-sampling channel in the voltage transformer group are used to collect voltage transformer signals to obtain the first voltage transformer signal and the second voltage transformer signal. When the channel difference value obtained between the first voltage transformer signal and the second voltage transformer signal is greater than a preset value, it is determined that the sampling channel of the voltage transformer online monitoring device is abnormal, and then the three-phase unbalance difference value of each voltage transformer group is calculated. When the three-phase unbalance difference value is greater than the preset value, it is confirmed that the voltage transformer with the three-phase unbalance difference value greater than the preset value is abnormal. The sampling channel of the group is abnormal; if multiple voltage transformer groups are not from the same voltage source, the input voltage, output voltage and three-phase voltage of the substation within the preset time are collected. If the input voltage, output voltage and three-phase voltage change inconsistently within the preset time, it is determined whether the change trend is a mutation. If it is a mutation, it is determined that the sampling channel of the voltage transformer online monitoring device is abnormal. This method evaluates the signal sampling channel status of the voltage transformer online monitoring device from three dimensions: the same voltage and same phase sequence diagnosis method, the same voltage and different phase sequence diagnosis method, and the different voltage diagnosis method. It can effectively diagnose abnormal channels and improve the accuracy and reliability of data collected by the signal sampling channel.

[0011] As a preferred solution, the channel difference value is obtained according to the first voltage transformer signal and the second voltage transformer signal collected by the second sampling channel, specifically:

[0012] The channel difference value is calculated according to the first voltage transformer signal and the second voltage transformer signal using a calculation formula, wherein the calculation formula is:

[0013] f=(xx′) / x′

[0014] Wherein, f represents the channel difference value, x represents the first voltage transformer signal, and x′ represents the second voltage transformer signal.

[0015] As a preferred solution, the three-phase unbalance difference value of each voltage transformer group is calculated. When the three-phase unbalance difference value is greater than a preset second threshold, it is confirmed that the sampling channel of the voltage transformer group whose three-phase unbalance difference value is greater than the preset second threshold is abnormal. Specifically:

[0016] Calculate the three-phase unbalance of each sampling channel in each voltage transformer group using the amplitude and phase angle;

[0017] The three-phase unbalance of each sampling channel in each voltage transformer group is compared to obtain an unbalance difference value, wherein the calculation formula is:

[0018] V=|ε-ε′|

[0019] Wherein, V represents the imbalance difference value, ε represents the imbalance of the first sampling channel, and ε′ represents the imbalance of the second sampling channel;

[0020] If the unbalance difference value is greater than the preset second threshold, it is determined that the sampling channel of the voltage transformer group is abnormal.

[0021] As a preferred solution, the preset first threshold value and the preset second threshold value are obtained according to the accuracy level of the sampling channel;

[0022] When the accuracy level of the sampling channel changes, the preset first threshold and the preset second threshold can be modified according to the change in the accuracy level of the sampling channel.

[0023] As a preferred solution, in order to solve the same technical problem, an embodiment of the present invention further provides a signal sampling channel multi-dimensional diagnosis system, including an identification module, an acquisition module, a first judgment module and a second judgment module;

[0024] The identification module is used to identify whether multiple voltage transformer groups are the same voltage source;

[0025] The acquisition module is configured to, when the multiple voltage transformer groups are from the same voltage source, respectively use a first sub-sampling channel and a second sub-sampling channel to acquire voltage transformer signals to obtain a first voltage transformer signal and a second voltage transformer signal, so that the diagnostic system can obtain a channel difference value based on the first voltage transformer signal and the second voltage transformer signal acquired by the second sampling channel;

[0026] The first judgment module is configured to determine that a sampling channel of the voltage transformer online monitoring device is abnormal when the channel difference value is greater than a preset first threshold value, and calculate the three-phase unbalance difference value of each voltage transformer group; when the three-phase unbalance difference value is greater than a preset second threshold value, confirm that the sampling channel of the voltage transformer group whose three-phase unbalance difference value is greater than the preset second threshold value is abnormal;

[0027] The second judgment module is used to collect the input voltage, output voltage and three-phase voltage of the substation within a preset time when multiple voltage transformer groups are not from the same voltage source. If the input voltage, output voltage and three-phase voltage do not change consistently within the preset time, it is judged whether the change trend is a mutation. If it is a mutation, it is judged that the sampling channel of the voltage transformer online monitoring device is abnormal.

[0028] As a preferred solution, the first judgment module includes an imbalance calculation unit, an imbalance difference value calculation unit and a comparison unit.

[0029] The unbalance calculation unit is used to calculate the three-phase unbalance of each sampling channel in each voltage transformer group using amplitude and phase angle;

[0030] The imbalance difference value calculation unit is used to compare the three-phase imbalance of each sampling channel in each voltage transformer group to obtain the imbalance difference value, wherein the calculation formula is:

[0031] V=|ε-ε′|

[0032] Wherein, V represents the imbalance difference value, ε represents the imbalance of the first sampling channel, and ε′ represents the imbalance of the second sampling channel;

[0033] The comparison unit is configured to determine that a sampling channel of the voltage transformer group is abnormal if the unbalance difference value is greater than a preset second threshold value.

[0034] As a preferred solution, in order to solve the same technical problem, an embodiment of the present invention also provides a multi-dimensional diagnostic device for a signal sampling channel, including: a memory, a processor, and a computer program stored in the memory and runnable on the processor. When the processor executes the program, a multi-dimensional diagnostic method for a signal sampling channel as shown in an embodiment of the present invention is implemented.

[0035] As a preferred solution, in order to solve the same technical problem, an embodiment of the present invention further provides a storage medium, on which a computer program is stored. When the computer program is executed by a processor, a multi-dimensional diagnostic method for a signal sampling channel is implemented as shown in an embodiment of the present invention.

[0036] The present invention identifies whether multiple voltage sensor groups are the same voltage source. When multiple voltage transformer groups are the same voltage source, the first sub-sampling channel and the second sub-sampling channel in the voltage transformer group are used to collect voltage transformer signals to obtain the first voltage transformer signal and the second voltage transformer signal. When the channel difference value obtained by the first voltage transformer signal and the second voltage transformer signal is greater than a preset value, it is determined that the sampling channel of the voltage transformer online monitoring device is abnormal, and then the three-phase unbalance difference value of each voltage transformer group is calculated. When the three-phase unbalance difference value is greater than the preset value, it is confirmed that the sampling channel of the voltage transformer group whose three-phase unbalance difference value is greater than the preset value is abnormal. The sampling channel is abnormal; if multiple voltage transformer groups are not from the same voltage source, the input voltage, output voltage and three-phase voltage of the substation within the preset time are collected. If the input voltage, output voltage and three-phase voltage do not change consistently within the preset time, it is determined whether the change trend is a mutation. If it is a mutation, it is determined that the sampling channel of the voltage transformer online monitoring device is abnormal. This method evaluates the signal sampling channel status of the voltage transformer online monitoring device from three dimensions: the same voltage and same phase sequence diagnosis method, the same voltage and different phase sequence diagnosis method, and the different voltage diagnosis method. It can effectively diagnose abnormal channels and improve the accuracy and reliability of data collected by the signal sampling channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 : A schematic flow chart of an embodiment of the multi-dimensional diagnostic method for signal sampling channels provided by the present invention;

[0038] Figure 2 : Schematic diagram of a device for online monitoring of voltage transformer metrological performance, which is an embodiment of the multi-dimensional diagnostic method for signal sampling channels provided by the present invention;

[0039] Figure 3 : A wiring schematic diagram of an online monitoring device for voltage transformer metering performance in a 220kV substation, which is an embodiment of the multi-dimensional diagnostic method for signal sampling channels provided by the present invention;

[0040] Figure 4 : A schematic diagram of the device structure of an embodiment of the signal sampling channel multi-dimensional diagnostic device provided by the present invention. DETAILED DESCRIPTION

[0041] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0042] Example 1

[0043] Please refer to Figure 1 , a multi-dimensional diagnostic method for a signal sampling channel provided by an embodiment of the present invention, the multi-dimensional diagnostic method for a signal sampling channel includes steps 101 to 104, each of which is specifically as follows:

[0044] Step 101: Identify whether multiple voltage transformer groups are the same voltage source.

[0045] In this embodiment, if Figure 2 The dual-channel signal sampling method described above completes wiring inside the device, while externally, a voltage transformer is still connected to a signal acquisition channel. This reduces the workload of external wiring, avoids repeated wiring of the same signal at the construction site, and reduces equipment installation risks. The online voltage transformer metrological performance monitoring device includes multiple sets of sensors, and different judgment methods are required depending on whether the multiple sets of voltage transformers are from the same voltage source. When the multiple sets of voltage transformers collected by the online voltage transformer metrological performance monitoring device are from the same voltage source, the relative error of the same voltage signal in the two channels is compared, and then combined with the error limit of the sampling channel itself, the maximum allowable relative deviation of the two sampling channels is calculated as the difference threshold to achieve channel status assessment. The three-phase imbalance of the multiple sets of the same voltage source is then calculated as a diagnostic method for whether the sampling channels are abnormal. When the multiple sets of voltage transformers collected by the online monitoring device are from different voltage sources, such as collecting the input and output voltages of a transformer, the changing trends of the transformer input and output voltages are analyzed to determine whether they are synchronized.

[0046] Step 102: When the multiple voltage transformer groups are the same voltage source, use the first subsampling channel and the second subsampling channel in the voltage transformer group to collect voltage transformer signals to obtain a first voltage transformer signal and a second voltage transformer signal, so that the diagnostic system can obtain a channel difference value based on the first voltage transformer signal and the second voltage transformer signal.

[0047] Optionally, a channel difference value is obtained according to the first voltage transformer signal and the second voltage transformer signal collected by the second sampling channel, specifically:

[0048] The channel difference value is calculated according to the first voltage transformer signal and the second voltage transformer signal using a calculation formula, wherein the calculation formula is:

[0049] f=(xx′) / x′

[0050] Wherein, f represents the channel difference value, x represents the first voltage transformer signal, and x′ represents the second voltage transformer signal.

[0051] Optionally, the preset first threshold and the preset second threshold are obtained according to the accuracy level of the sampling channel;

[0052] When the accuracy level of the sampling channel changes, the preset first threshold and the preset second threshold can be modified according to the change in the accuracy level of the sampling channel.

[0053] In this embodiment, when multiple voltage transformer groups are the same voltage source, based on the existing voltage transformer metering performance online monitoring device, the signal acquisition terminals are expanded by 1 times, that is, the same voltage signal is connected to two sampling channels at the same time. When each voltage transformer signal enters the online monitoring device, two sampling channels are used for simultaneous sampling. When a voltage signal in one of the two sampling channels shows a large difference, one channel in the voltage sampling loop is abnormal. The channel difference value is determined by the following formula:

[0054] f=(xx′) / x′,

[0055] Wherein, x represents the first sampling channel when sampling the same voltage signal, x′ represents the second sampling channel when sampling the same voltage signal, and f represents the channel difference value.

[0056] Step 103: When the channel difference value is greater than the preset first threshold value, it is determined that the sampling channel of the voltage transformer online monitoring device is abnormal, and the three-phase imbalance difference value of each voltage transformer group is calculated. When the three-phase imbalance difference value is greater than the preset second threshold value, it is confirmed that the sampling channel of the voltage transformer group whose three-phase imbalance difference value is greater than the preset second threshold value is abnormal.

[0057] Optionally, the amplitude and phase angle are used to calculate the three-phase unbalance of each sampling channel in each voltage transformer group;

[0058] The three-phase unbalance of each sampling channel in each voltage transformer group is compared to obtain an unbalance difference value, wherein the calculation formula is:

[0059] V=|ε-ε′|

[0060] Wherein, V represents the imbalance difference value, ε represents the imbalance of the first sampling channel, and ε′ represents the imbalance of the second sampling channel;

[0061] If the unbalance difference value is greater than the preset second threshold, it is determined that the sampling channel of the voltage transformer group is abnormal.

[0062] In this embodiment, by comparing the relative errors of the same voltage signal in the two channels, combined with the error limit of the sampling channel itself, the maximum allowable relative deviation of the two sampling channels is calculated as the threshold of the difference, thereby realizing the first step of the channel status assessment. At this time, it is only known which phase sampling has an abnormality, but it is impossible to determine which group of channels in the dual channels is abnormal. When |f| is greater than the preset value, it means that the difference is large and the signal sampling is abnormal. When one of the two sampling channels of the same voltage signal has an abnormality, this method is used to diagnose the sampling channel abnormality, but it cannot be detected which group of voltage transformer channels has an abnormality.

[0063] When multiple sets of voltage transformers collected by the online monitoring device come from the same voltage source, the three-phase voltage imbalance is calculated and compared across the same set of voltage transformers in dual-channel sampling. The difference between the two, exceeding the maximum allowable deviation of the sampling channel, is used as the anomaly threshold. Same-voltage, different-phase-sequence diagnosis evaluates a set of three-phase voltages, A, B, and C. Therefore, when an anomaly occurs, it's difficult to determine which of the three phases is at fault. In this case, the same-voltage, same-phase-sequence diagnosis method is combined to locate the abnormal channel.

[0064] For example, in a substation with two mother transformers running in parallel, or in a substation where the outgoing line is used as the meter, the amplitude and phase angle are used to calculate the three-phase imbalance of two sampling channels of multiple voltage transformers with the same voltage source according to the existing formula. When the imbalance of any group exceeds the preset value, the sampling signal of that group is abnormal. The imbalance difference value is determined by the following formula:

[0065] V=|ε-ε′|

[0066] Among them, when the primary voltage sources of the voltage transformers collected by the first and second groups of the online monitoring device are the same, ε represents the three-phase voltage unbalance of the first group, ε′ represents the three-phase voltage unbalance of the second group, and V represents the difference value of the three-phase voltage unbalance.

[0067] As an example of this embodiment, when |f| > 0.04%, the difference is large and the signal sampling is abnormal. The 0.04% is based on the fact that the signal acquisition units are all at level 0.02. In extreme cases, one is +0.02% and the other is -0.02%, so the maximum difference between the two is 0.04%. When |ε-ε′| > 0.04%, the difference is large and the signal sampling is abnormal.

[0068] As an example of this embodiment, the substation is a dual-mother parallel operation substation. The voltage transformer metering performance online monitoring device collects the output signals of the 220kV I-mother and II-mother voltage transformers and the 110kV I-mother and II-mother voltage transformers, and collects a total of 4 groups of 12 voltage transformer signals. The wiring principle of the voltage transformer metering performance online monitoring device in the station is as follows: Figure 3 As shown. Each signal sampling channel of the voltage transformer metering performance online monitoring device is designed as a dual sampling channel, and the wiring has been completed internally. Figure 3 The dotted lines are used to mark the internal wiring of the device. Assume that the voltage signals collected by the voltage transformer metering performance online monitoring device are as follows:

[0069] V 1A 57.777V; V′ 1A 57.761V; V 1B 57.667V; V′ 1B 57.657V; V 1C 57.817V; V′ 1C 57.555V;

[0070] V 2A 56.621V; V′ 2A 56.631V; V 2B 57.676V; V′ 2B 57.687V; V 2C 57.821V; V′ 2C 57.819V;

[0071] V 3A 57.333V; V′ 3A 57.325V; V 3B 57.431V; V′ 3B 57.564V; V 3C 57.353V; V′ 3C 57.349V;

[0072] V 4A 57.340V; V′ 4A 57.331V; V 4B 57.444V; V′ 4B 57.437V; V 4C 57.360V; V′ 4C 57.351V.

[0073] The signal sampling channel diagnosis of the voltage transformer metering performance online monitoring device adopts the same voltage and phase sequence diagnosis method and the steps are as follows:

[0074] Compare the difference between Vxn and V′xn and calculate according to the formula f=(Vxn-V′xn) / V′xn. The result is as follows: f 1A =(V 1A -V′ 1A ) / V′ 1A =0.028%; f 1B =(V1B -V′ 1B ) / V′ 1B =0.017%; f 1C =(V 1C -V′ 1C ) / V′ 1C =0.455%;

[0075] f 2A =(V 2A -V′ 2A ) / V′ 2A =-0.017%; f 2B =(V 2B -V′ 2B ) / V′ 2B =-0.019%; f 2C =(V 2C -V′ 2C ) / V′ 2C =0.003%;

[0076] f 3A =(V 3A -V′ 3A ) / V′ 3A =-0.014%; f 3B =(V 3B -V′ 3B ) / V′ 3B =-0.231%;f 3C =(V 3C -V′ 3C ) / V′ 3C =0.007%;

[0077] f 4A =(V 4A -V′ 4A ) / V′ 4A =0.016%; f 4B =(V 4B -V′ 4B ) / V′ 4B =0.012%; f 4C =(V 4C -V′ 4C ) / V′ 4C =0.016%

[0078] Calculation shows that the first group C channel and the third group B channel of the voltage transformer metering performance online monitoring device are abnormal, but it cannot be determined which channel between Vxn and V′xn is the abnormal channel, and further calculation is needed.

[0079] The calculation of three-phase voltage imbalance requires the use of amplitude and phase angle, and is performed according to the existing formula.

[0080] According to the three-phase imbalance of the transmission line should be within 4%, the three-phase imbalance of the four groups of voltage transformers is calculated respectively, and the imbalance of the two sampling channels of each group of voltage transformers is obtained. When the imbalance of any group exceeds 4%, the sampling signal of that group is abnormal. Assuming that the imbalance of the first sampling channel of the first group of voltage transformers exceeds 4%, combined with the abnormality of the phase C of channel 1 in step 1), the abnormal channel can be located from the phase C of the first sampling channel, that is, channel V 13 abnormal.

[0081] Step 104: When multiple voltage transformer groups are not from the same voltage source, the input voltage, output voltage and three-phase voltage of the substation within a preset time are collected. If the input voltage, output voltage and three-phase voltage do not change consistently within the preset time, it is determined whether the change trend is a sudden change. If it is a sudden change, it is determined that the sampling channel of the voltage transformer online monitoring device is abnormal.

[0082] In this embodiment, when the online monitoring device collects multiple sets of voltage transformers from different voltage sources, by analyzing long-term sampling data, it is observed whether the voltage change trends of the transformer input and output are the same, and the abnormality of the signal sampling channel is judged. When the sampling signal of a certain channel deviates from that of other channels, it can be known that the channel is abnormal. For example, when collecting the input and output voltages of the transformer, by analyzing whether the change trends of the transformer input and output voltages are synchronized, and whether the collected A, B, and C three-phase voltage changes are synchronized, it is necessary to distinguish whether it is a sudden change or a gradual change when asynchrony occurs, to achieve signal sampling channel diagnosis. When the change trends of the input and output signals are consistent, or are consistent after a sudden change, the sampling channel is normal; otherwise, the signal sampling is abnormal.

[0083] As an example of this embodiment, the first and second groups of voltage transformers are the input ends of the substation, and the third and fourth groups of voltage transformers are the output ends of the transformer. Figure 3 As shown in the figure, when the input voltage of the transformer increases, the output voltage also increases. Only when the transformer tap changer is activated, the output voltage will suddenly change, and the three phases A, B, and C will suddenly change at the same time, but the change trend of the input and output is still consistent. If the voltage transformer measurement performance online monitoring device is used for long-term sampling, it is found that the change trend of the B phase of the second sampling channel of the third group of voltage transformers is opposite to that of the A and C phases, then the results of the same voltage and phase sequence diagnostic method can be used in combination with the steps to locate V' 3B abnormal.

[0084] Example 2

[0085] Accordingly, see Figure 4 , Figure 44 is a schematic diagram of the structure of a signal sampling channel multi-dimensional diagnosis system provided by the present invention. As shown in the figure, the signal sampling channel multi-dimensional diagnosis system includes an identification module 401, an acquisition module 402, a first judgment module 403 and a second judgment module 404;

[0086] The identification module 401 is used to identify whether multiple voltage transformer groups are the same voltage source;

[0087] The acquisition module 402 is configured to acquire voltage transformer signals using a first sub-sampling channel and a second sub-sampling channel, respectively, to obtain a first voltage transformer signal and a second voltage transformer signal when the multiple voltage transformer groups are from the same voltage source, so that the diagnostic system can obtain a channel difference value based on the first voltage transformer signal and the second voltage transformer signal acquired by the second sampling channel.

[0088] The first judgment module 403 is configured to determine that a sampling channel of the voltage transformer online monitoring device is abnormal when the channel difference value is greater than a preset first threshold value, and calculate a three-phase unbalance difference value of each voltage transformer group; when the three-phase unbalance difference value is greater than a preset second threshold value, confirm that the sampling channel of the voltage transformer group whose three-phase unbalance difference value is greater than the preset second threshold value is abnormal;

[0089] The second judgment module 404 is used to collect the input voltage, output voltage and three-phase voltage of the substation within a preset time when multiple voltage transformer groups are not from the same voltage source. If the input voltage, output voltage and three-phase voltage do not change consistently within the preset time, it is determined whether the change trend is a sudden change. If it is a sudden change, it is determined that the sampling channel of the voltage transformer online monitoring device is abnormal.

[0090] Optionally, the first judgment module 403 includes an imbalance calculation unit 4031, an imbalance difference value calculation unit 4032 and a comparison unit 4033.

[0091] The imbalance calculation unit 4031 is used to calculate the three-phase imbalance of each sampling channel in each voltage transformer group using amplitude and phase angle;

[0092] The imbalance difference value calculation unit 4032 is used to compare the three-phase imbalance of each sampling channel in each voltage transformer group to obtain an imbalance difference value, wherein the calculation formula is:

[0093] V=|ε-ε′|

[0094] Wherein, V represents the imbalance difference value, ε represents the imbalance of the first sampling channel, and ε′ represents the imbalance of the second sampling channel;

[0095] The comparison unit 4033 is configured to determine that a sampling channel of the voltage transformer group is abnormal if the unbalance difference value is greater than a preset second threshold value.

[0096] For more detailed working principles and processes of this embodiment, please refer to, but not limited to, the relevant description of Embodiment 1.

[0097] The signal sampling channel multi-dimensional diagnosis system executes the signal sampling channel multi-dimensional diagnosis method, by identifying whether multiple voltage sensor groups are the same voltage source. When multiple voltage transformer groups are the same voltage source, the first sub-sampling channel and the second sub-sampling channel in the voltage transformer group are used to collect the voltage transformer signal to obtain the first voltage transformer signal and the second voltage transformer signal. When the channel difference value obtained by the first voltage transformer signal and the second voltage transformer signal is greater than the preset value, it is determined that the sampling channel of the voltage transformer online monitoring device is abnormal, and then the three-phase unbalance difference value of each voltage transformer group is calculated. When the three-phase unbalance difference value is greater than the preset value, it is confirmed that the three-phase unbalance difference value is large. The sampling channel of the voltage transformer group with a preset value is abnormal; if multiple voltage transformer groups are not from the same voltage source, the input voltage, output voltage and three-phase voltage of the substation within the preset time are collected. If the input voltage, output voltage and three-phase voltage do not change consistently within the preset time, it is determined whether the change trend is a mutation. If it is a mutation, it is determined that the sampling channel of the voltage transformer online monitoring device is abnormal. This method evaluates the signal sampling channel status of the voltage transformer online monitoring device from three dimensions: the same voltage and same phase sequence diagnosis method, the same voltage and different phase sequence diagnosis method, and the different voltage diagnosis method. It can effectively diagnose abnormal channels and improve the accuracy and reliability of data collected by the signal sampling channel.

[0098] Example 3

[0099] Accordingly, the signal sampling channel multi-dimensional diagnostic device provided by the present invention includes: a processor and a memory,

[0100] A computer program is stored in the memory, and the computer program is configured to be executed by a processor, and the processor performs operations corresponding to the multi-dimensional diagnosis method of the signal sampling channel as shown in the first embodiment of the present application.

[0101] Example 4

[0102] Accordingly, the present invention provides a storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the multi-dimensional diagnosis method for signal sampling channels as shown in the first embodiment are implemented.

[0103] Compared with the prior art, the present invention provides a multi-dimensional diagnosis method and system for signal sampling channels. By identifying whether multiple voltage sensor groups are the same voltage source, when multiple voltage transformer groups are the same voltage source, the first sub-sampling channel and the second sub-sampling channel in the voltage transformer group are used to collect voltage transformer signals to obtain the first voltage transformer signal and the second voltage transformer signal. When the channel difference value obtained by the first voltage transformer signal and the second voltage transformer signal is greater than the preset value, it is determined that the sampling channel of the voltage transformer online monitoring device is abnormal, and then the three-phase unbalance difference value of each voltage transformer group is calculated. When the three-phase unbalance difference value is greater than the preset value, it is confirmed that the three-phase unbalance difference The sampling channel of the voltage transformer group whose value is greater than the preset value is abnormal. If multiple voltage transformer groups are not from the same voltage source, the input voltage, output voltage and three-phase voltage of the substation within the preset time are collected. If the input voltage, output voltage and three-phase voltage do not change consistently within the preset time, it is determined whether the change trend is a mutation. If it is a mutation, it is determined that the sampling channel of the voltage transformer online monitoring device is abnormal. This method evaluates the signal sampling channel status of the voltage transformer online monitoring device from three dimensions: the same voltage and same phase sequence diagnosis method, the same voltage and different phase sequence diagnosis method, and the different voltage diagnosis method. It can effectively diagnose abnormal channels and improve the accuracy and reliability of data collected by the signal sampling channel.

[0104] The specific embodiments described above further illustrate the objectives, technical solutions, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included within the scope of protection of the present invention for those skilled in the art.

Claims

1. A multi-dimensional diagnostic method for signal sampling channels, characterized in that: include: Identify whether multiple voltage transformer groups are the same voltage source; When the multiple voltage transformer groups are the same voltage source, using a first sub-sampling channel and a second sub-sampling channel in the voltage transformer group to collect voltage transformer signals to obtain a first voltage transformer signal and a second voltage transformer signal, so that the diagnostic system obtains a channel difference value according to the first voltage transformer signal and the second voltage transformer signal; When the channel difference value of a certain voltage transformer group is greater than a preset first threshold, it is determined that the sampling channel of the voltage transformer group is abnormal, and the three-phase unbalance of the first sub-sampling channel and the second sub-sampling channel in the voltage transformer group is calculated. When the three-phase unbalance of a certain sub-sampling channel of the voltage transformer group is greater than 4%, it is confirmed that the sub-sampling channel of the voltage transformer group is abnormal; When the multiple voltage transformer groups are not from the same voltage source, the input voltage and output voltage of the substation within a preset time are collected to determine whether the change trends of the input voltage and the output voltage are consistent within the preset time. If not, determine whether the change trend is a mutation. If it is a mutation, determine that the sampling channel of the voltage transformer group is abnormal.

2. The multi-dimensional diagnostic method for signal sampling channels according to claim 1, characterized in that: The channel difference value is obtained according to the first voltage transformer signal and the second voltage transformer signal collected by the second sampling channel, specifically: The channel difference value is calculated according to the first voltage transformer signal and the second voltage transformer signal using a calculation formula, wherein the calculation formula is: f=(xx´) / x´ Where f represents the channel difference value, x represents the first voltage transformer signal, and x´ represents the second voltage transformer signal.

3. A multi-dimensional diagnostic system for signal sampling channels, characterized in that: It includes an identification module, a collection module, a first judgment module and a second judgment module; The identification module is used to identify whether multiple voltage transformer groups are the same voltage source; The acquisition module is configured to, when the multiple voltage transformer groups are the same voltage source, respectively use a first sub-sampling channel and a second sub-sampling channel to acquire voltage transformer signals to obtain a first voltage transformer signal and a second voltage transformer signal, so that the diagnostic system obtains a channel difference value based on the first voltage transformer signal and the second voltage transformer signal acquired by the second sampling channel; The first judgment module is configured to determine that a sampling channel of a certain voltage transformer group is abnormal when the channel difference value of the certain voltage transformer group is greater than a preset first threshold value, and calculate the three-phase unbalance of the first sub-sampling channel and the second sub-sampling channel in the certain voltage transformer group; and confirm that the sub-sampling channel of the certain voltage transformer group is abnormal when the three-phase unbalance of the certain sub-sampling channel of the certain voltage transformer group is greater than 4%; The second judgment module is used to collect the input voltage and output voltage of the substation within a preset time when the multiple voltage transformer groups are not from the same voltage source, and determine whether the change trends of the input voltage and the output voltage are consistent within the preset time; if not, determine whether the change trend is a mutation; if it is a mutation, determine that the sampling channel of the voltage transformer group is abnormal.

4. A multi-dimensional diagnostic device for signal sampling channels, characterized in that: include: memory for storing computer programs; A processor, configured to implement the multi-dimensional diagnosis method for signal sampling channels according to any one of claims 1 to 2 when executing the computer program.

5. A storage medium, characterized in that The storage medium stores a computer program, which, when executed by a processor, implements the steps of the multi-dimensional diagnostic method for signal sampling channels according to any one of claims 1 to 2.

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