Method and device for online monitoring of switchgear

Abstract

The present invention provides a method and device for online monitoring of switchgear, which realizes data preprocessing by filtering the real-time mechanical characteristic curve, can reduce the amount of data calculation, is beneficial to subsequent data processing, and occupies little data memory. In addition, since the similarity of the curves is compared, it is not affected by whether the number of sampling points of the compared curves is the same, whether there is a delay, and whether the horizontal coordinates are consistent.

Description

Technical Field

[0001] The invention relates to the field of power systems, and in particular to a method and a device for online monitoring of switchgear. Background Art

[0002] Medium voltage switchgear equipment is a device that opens and closes, controls and protects electricity in the power system, and its normal operation needs to be guaranteed. In the prior art, some factories adopt online monitoring, that is, real-time monitoring of a component in the switchgear to detect the fault of the component in time. Therefore, how to analyze the data obtained during online monitoring and detect faults in time is an urgent problem to be solved. Summary of the invention

[0003] In view of this, the present invention proposes a method for online monitoring of a switchgear, comprising: obtaining a real-time mechanical characteristic curve of a monitored component, the real-time mechanical characteristic curve having a total of m sampling points, the monitored component having a preset reference mechanical characteristic curve, the reference mechanical characteristic curve being obtained when the monitored component is in a normal working state, the method further comprising:

[0004] Retaining the first sampling point and the mth sampling point of the real-time mechanical characteristic curve;

[0005] Taking the first sampling point of the real-time mechanical characteristic curve as the initial first reference point;

[0006] Assign the value of f to 1;

[0007] Obtaining an absolute value of a difference between an i+fth sampling point in the real-time mechanical characteristic curve and the first reference point as a first absolute value, wherein the i-th sampling point represents the first reference point;

[0008] determining whether to retain the i+fth sampling point and the i+f-1th sampling point according to the first absolute value;

[0009] If the result of the determination is yes, the i+fth sampling point is used as the updated first reference point, and the operation of assigning the value of f to 1 is returned to execute, until the absolute value of the difference between the m-1th sampling point and the first reference point is obtained as the first absolute value, and it is determined whether to retain the m-1th sampling point and the m-2th sampling point according to the first absolute value;

[0010] The curve formed by all the retained sampling points is used as the filtered real-time mechanical characteristic curve;

[0011] The similarity between the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve is determined, and whether the monitored component fails is determined based on the similarity.

[0012] According to the method as described above, optionally, it also includes:

[0013] If the determination result is no, after updating the value of f to f+1, the process returns to executing the operation of obtaining the absolute value of the difference between the i+fth sampling point in the real-time mechanical characteristic curve and the first reference point as the first absolute value.

[0014] According to the method as described above, optionally, before obtaining the absolute value of the difference between the i+fth sampling point in the real-time mechanical characteristic curve and the first reference point as the first absolute value, the method further includes:

[0015] Obtaining an original reference mechanical characteristic curve of the monitored component under normal working conditions, the reference mechanical characteristic curve having n sampling points;

[0016] The first sampling point and the nth sampling point of the reference mechanical characteristic curve are retained;

[0017] The first sampling point of the reference mechanical characteristic curve is used as the initial second reference point;

[0018] Assign the value of s to 1;

[0019] Obtaining an absolute value of a difference between a j+sth sampling point in the reference mechanical characteristic curve and the second reference point as a second absolute value, wherein the jth sampling point represents the second reference point;

[0020] determining whether to retain the j+sth sampling point and the j+s-1th sampling point according to the second absolute value;

[0021] If the result of the determination is yes, the j+sth sampling point is used as the updated second reference point, and the operation of assigning the value of s to 1 is returned to execute until the first absolute value of the difference between the n-1th sampling point and the first reference point is obtained and it is determined whether to retain the n-1th sampling point and the n-2th sampling point according to the first absolute value;

[0022] The curve formed by all the retained sampling points is used as the final reference mechanical characteristic curve.

[0023] According to the method as described above, optionally, determining whether to retain the j+sth sampling point and the j+s-1th sampling point according to the second absolute value includes:

[0024] Determine whether the second absolute value corresponding to the j+sth sampling point is greater than or equal to a filtering threshold;

[0025] If the judgment result is yes, the j+sth sampling point and the j+s-1th sampling point are retained.

[0026] According to the method as described above, optionally, determining whether to retain the i+fth sampling point and the i+f-1th sampling point according to the absolute value includes:

[0027] Determine whether the absolute value corresponding to the i+fth sampling point is greater than or equal to a filtering threshold;

[0028] If the determination result is yes, the i+fth sampling point and the i+f-1th sampling point are retained.

[0029] According to the method as described above, optionally, determining the similarity between the filtered real-time mechanical characteristic curve and the filtered reference mechanical characteristic curve comprises:

[0030] determining a first minimum Euclidean distance between each sampling point of the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve;

[0031] If a first minimum Euclidean distance is greater than or equal to a first preset threshold, determining the sampling point corresponding to the first minimum Euclidean distance as the first recording point;

[0032] Obtaining a first weight value according to the number of the first recording points and the minimum Euclidean distance corresponding to each of the first recording points;

[0033] determining a second minimum Euclidean distance between each sampling point of the filtered reference mechanical characteristic curve and the real-time mechanical characteristic curve;

[0034] If the second minimum Euclidean distance is greater than or equal to a second preset threshold, determining the sampling point corresponding to the second minimum Euclidean distance as the second recording point;

[0035] Obtaining a second weight value according to the number of the second recording points and the minimum Euclidean distance corresponding to each of the second recording points;

[0036] The similarity between the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve is determined according to the first weight value and the second weight value.

[0037] According to the method as described above, optionally,

[0038] The first weight value dW1 is determined according to the following formula:

[0039] Wherein, t represents the number of first record points, w(t) is a function related to t, and Ep represents the minimum Euclidean distance corresponding to the pth first record point;

[0040] The second weight value dw2 is determined according to the following formula:

[0041] Wherein, k represents the number of second record points, w(k) is a function related to k, and Eq represents the minimum Euclidean distance corresponding to the qth second record point.

[0042] According to the method described above, optionally, w(t)=1 / t, w(k)=1 / k.

[0043] The present invention also provides a device for online monitoring of a switchgear, comprising:

[0044] A first acquisition unit, used for acquiring a real-time mechanical characteristic curve of a monitored component, the real-time mechanical characteristic curve having a total of m sampling points, the monitored component having a preset reference mechanical characteristic curve, the reference mechanical characteristic curve being acquired when the monitored component is in a normal working state;

[0045] The device also includes:

[0046] A retaining unit, used for retaining the first sampling point and the mth sampling point of the real-time mechanical characteristic curve;

[0047] An initial reference point unit, used for taking the first sampling point of the real-time mechanical characteristic curve as an initial first reference point;

[0048] An assignment unit, used to assign the value of f to 1;

[0049] a second acquisition unit, configured to acquire an absolute value of a difference between an i+fth sampling point in the real-time mechanical characteristic curve and the first reference point as a first absolute value, wherein the ith sampling point represents the first reference point;

[0050] a first determining unit, configured to determine whether to retain the i+fth sampling point and the i+f-1th sampling point according to the first absolute value, and trigger a first updating unit if the determination result is yes;

[0051] The first updating unit is used to use the i+fth sampling point as the updated first reference point and trigger the assignment unit until the absolute value of the difference between the m-1th sampling point and the first reference point is obtained as the first absolute value and whether to retain the m-1th sampling point and the m-2th sampling point is determined according to the first absolute value;

[0052] A composition unit, used for taking a curve composed of all the retained sampling points as a filtered real-time mechanical characteristic curve;

[0053] A second determination unit is used to determine the similarity between the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve, and determine whether the monitored component fails according to the similarity.

[0054] According to the device as described above, optionally, it further comprises:

[0055] A second updating unit is used to update the value of f to f+1 and then trigger the second acquiring unit.

[0056] According to the device as described above, optionally,

[0057] The first acquisition unit is also used to acquire an original reference mechanical characteristic curve of the monitored component under normal working conditions, the reference mechanical characteristic curve having n sampling points;

[0058] The retaining unit is also used to retain the first sampling point and the nth sampling point of the reference mechanical characteristic curve;

[0059] The initial reference point unit is also used to use the first sampling point of the reference mechanical characteristic curve as the initial second reference point;

[0060] The assignment unit is also used to assign the value of s to 1;

[0061] The second acquisition unit is further used to acquire an absolute value of a difference between a j+sth sampling point in the reference mechanical characteristic curve and the second reference point as a second absolute value, wherein the jth sampling point represents the second reference point;

[0062] The first determining unit is further used to determine whether to retain the j+sth sampling point and the j+s-1th sampling point according to the second absolute value, and if the determination result is yes, trigger the first updating unit;

[0063] The first updating unit is further used to use the j+sth sampling point as the updated second reference point and trigger the assignment unit until a first absolute value of a difference between the n-1th sampling point and the first reference point is obtained and whether to retain the n-1th sampling point and the n-2th sampling point is determined according to the first absolute value;

[0064] The forming unit is also used to use the curve formed by all the retained sampling points as the final reference mechanical characteristic curve.

[0065] According to the above device, optionally, the first determining unit is specifically configured to:

[0066] Determine whether the second absolute value corresponding to the j+sth sampling point is greater than or equal to a filtering threshold;

[0067] If the judgment result is yes, the j+sth sampling point and the j+s-1th sampling point are retained.

[0068] According to the above device, optionally, the first determining unit is specifically configured to:

[0069] Determine whether the absolute value corresponding to the i+fth sampling point is greater than or equal to a filtering threshold;

[0070] If the determination result is yes, the i+fth sampling point and the i+f-1th sampling point are retained.

[0071] According to the device as described above, optionally, the second determining unit specifically includes:

[0072] a first determining subunit, configured to determine a first minimum Euclidean distance between each sampling point of the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve;

[0073] a second determining subunit, configured to determine, if a first minimum Euclidean distance is greater than or equal to a first preset threshold, a sampling point corresponding to the first minimum Euclidean distance as a first recording point;

[0074] a first acquisition subunit, configured to acquire a first weight value according to the number of the first recording points and the minimum Euclidean distance corresponding to each of the first recording points;

[0075] a third determination subunit, configured to determine a second minimum Euclidean distance between each sampling point of the filtered reference mechanical characteristic curve and the real-time mechanical characteristic curve;

[0076] a fourth determining subunit, configured to determine, if a second minimum Euclidean distance is greater than or equal to a second preset threshold, a sampling point corresponding to the second minimum Euclidean distance as a second recording point;

[0077] a second acquisition subunit, configured to acquire a second weight value according to the number of the second recording points and the minimum Euclidean distance corresponding to each of the second recording points;

[0078] A fifth determining subunit is used to determine the similarity between the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve according to the first weight value and the second weight value.

[0079] According to the device as described above, optionally,

[0080] The first acquisition subunit is specifically used for:

[0081] The first weight value dW1 is determined according to the following formula:

[0082] Wherein, t represents the number of first record points, w(t) is a function related to t, and Ep represents the minimum Euclidean distance corresponding to the pth first record point;

[0083] The second acquisition subunit is specifically used for:

[0084] The second weight value dw2 is determined according to the following formula:

[0085] Wherein, k represents the number of second record points, w(k) is a function related to k, and Eq represents the minimum Euclidean distance corresponding to the qth second record point.

[0086] The present invention also provides a device for online monitoring of a switchgear, wherein the switchgear comprises a plurality of monitored components, and the device comprises:

[0087] at least one memory for storing instructions;

[0088] At least one processor is configured to execute the method for online monitoring of a switchgear according to any one of the above items according to the instructions stored in the memory.

[0089] The present invention further provides a readable storage medium, wherein the readable storage medium stores machine-readable instructions. When the machine-readable instructions are executed by a machine, the machine executes the method for online monitoring of a switchgear according to any one of the above items.

[0090] It can be seen from the above scheme that, since the present invention realizes data preprocessing by filtering the real-time mechanical characteristic curve, it can reduce the amount of data calculation, is beneficial to subsequent data processing, and occupies less data memory. In addition, since it is to compare the similarity of the curves, it is not affected by whether the number of sampling points of the compared curves is the same, whether there is a delay, and whether the horizontal coordinates are consistent. BRIEF DESCRIPTION OF THE DRAWINGS

[0091] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that the above and other features and advantages of the present invention will be more apparent to those skilled in the art. In the accompanying drawings:

[0092] Figure 1 The figure is a flow chart of a method for online monitoring of a switchgear according to an embodiment of the present invention.

[0093] Figure 2 The figure is a flow chart of a method for online monitoring of a switchgear according to another embodiment of the present invention.

[0094] Figure 3 Schematic diagram of the structure of an apparatus for online monitoring of switchgear according to an embodiment of the present invention.

[0095] Figure 4 Schematic diagram of the structure of an apparatus for online monitoring of switchgear according to another embodiment of the present invention. DETAILED DESCRIPTION

[0096] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail with reference to the following embodiments.

[0097] In the present invention, it is necessary to obtain the real-time mechanical characteristic curve of the monitored component. For example, in the process of the trolley in the switch cabinet moving from the experimental position to the working position, its voltage value can be measured in real time by the sensor, and the curve composed of the multiple voltage values ​​can be used as the real-time mechanical characteristic curve; the monitored component can also be the drive shaft in the switch cabinet, and specifically the current value corresponding to the drive shaft moving from the closing position to the opening position can be monitored, and the curve composed of the multiple current values ​​can be used as the real-time mechanical characteristic curve. That is, the curve composed of the corresponding multiple sampling points in one operation of the monitored component is used as the real-time mechanical characteristic curve. The monitored component also corresponds to a preset reference mechanical characteristic curve, which is the mechanical characteristic curve of the monitored component when it is working normally.

[0098] Embodiment 1

[0099] This embodiment provides a method for online monitoring of a switchgear. The method is performed by a device for online monitoring of a switchgear, and the device can be integrated in a relay protection device.

[0100] like Figure 1 FIG. 1 is a flow chart of a method for online monitoring of a switchgear according to this embodiment. The method comprises:

[0101] Step 100: Obtain a real-time mechanical characteristic curve of a monitored component, where the real-time mechanical characteristic curve has m sampling points in total.

[0102] The monitored components can be set according to actual needs, such as the switch cabinet trolley, control shaft, ground knife, energy storage motor, opening and closing coil, etc., which will not be elaborated here. The real-time mechanical characteristic curve refers to the curve corresponding to the movement of the monitored component, which can be obtained by recording. Characteristics are, for example, current, voltage or vibration. The real-time mechanical characteristic curve is a curve composed of multiple sampling points, and the curve can be a curve of a complete action. For example, the trolley moves from one position to another, and the control shaft rotates from one position to another, which are all complete actions.

[0103] In addition, the monitored component has a preset reference mechanical characteristic curve. The reference mechanical characteristic curve is obtained when the monitored component is in normal working state, and the attributes of the reference mechanical characteristic curve are consistent with the real-time mechanical characteristic curve, such as current, voltage or vibration. The reference mechanical characteristic curve is composed of multiple sampling points, such as a curve of a complete action, such as a trolley moving from one position to another, and a control shaft rotating from one position to another, which are all complete actions.

[0104] The horizontal axis of each curve may be time, and the vertical axis may be the attribute value. The difference between the sampling points is the attribute difference, such as the voltage difference or the current difference.

[0105] Step 101, retaining the first sampling point and the mth sampling point of the real-time mechanical characteristic curve.

[0106] The first sampling point and the mth sampling point are retained to make the duration of the real-time mechanical characteristic curve consistent with the duration of the reference mechanical characteristic curve, so as to avoid the situation where the contours of the two curves are inconsistent due to the removal of the first sampling point or the mth sampling point, thereby causing errors in the monitoring results.

[0107] That is to say, no matter what the subsequent determination result is, the first sampling point and the last sampling point should be retained.

[0108] Step 102: taking the first sampling point of the real-time mechanical characteristic curve as the initial first reference point.

[0109] The real-time mechanical characteristic curve has m sampling points. According to the acquisition time, the earliest acquired sampling point is used as the first reference point.

[0110] Step 103, assign the value of f to 1.

[0111] The value of f can be regarded as an initial value. If step 103 is not triggered again, the value of f changes according to subsequent operations. If step 103 is triggered again, the value of f is still assigned to 1. The purpose of assigning f is to enable the value of f in step 104 to have a specific value.

[0112] It should be noted that there is no sequence between step 103 and step 101 and step 102.

[0113] Step 104 : obtaining an absolute value of a difference between an i+fth sampling point in the real-time mechanical characteristic curve and a first reference point as a first absolute value, wherein the ith sampling point represents the first reference point.

[0114] In this embodiment, the number of sampling points of the real-time mechanical characteristic curve is m. When the first sampling point is used as the first reference point, the absolute value of the difference between the second sampling point and the first sampling point is first obtained. Since the sampling point itself is a value representing an attribute, such as current, voltage, amplitude difference, etc., the difference between the sampling points is the current difference, voltage difference or amplitude difference, etc.

[0115] Step 105 , determining whether to retain the i+f th sampling point and the i+f-1 th sampling point according to the first absolute value, if the determination result is yes, executing step 106 .

[0116] Specifically, it can be determined whether the first absolute value corresponding to the i+fth sampling point is greater than or equal to a filtering threshold. If the determination result is yes, the i+fth sampling point and the i+f-1th sampling point are retained. If the determination result is no, the i+fth sampling point is not retained. The filtering threshold is preset and can be set according to actual needs. Step 105 can be performed immediately after step 104 is fully executed. It can be understood that if the i+f-1th sampling point has been retained, it does not need to be retained again. The i+fth sampling point and the previous sampling point are retained to make the contour of the curve as consistent as possible with the original curve shape. Not retaining here means not performing the retention operation, which does not mean that the i+fth sampling point will be abandoned, and it may be retained later.

[0117] This step can retain feature data while reducing data.

[0118] If the determination result of step 105 is no, the following operations may be selected:

[0119] After the value of f is updated to f+1, the operation returns to execute the operation of obtaining the first absolute value of the difference between the i+fth sampling point in the real-time mechanical characteristic curve and the first reference point.

[0120] This step is to increase the value of f by 1 and then assign it to f.

[0121] For example, in step 103, the initial value of f is 1, and step 104 obtains the absolute value of the difference between the second sampling point and the first sampling point. If the determination result based on the absolute value is no, the second sampling point and the first sampling point are not retained, and the value of f is updated to 2, and step 104 is executed. Since the first sampling point has been retained, even if the determination result of step 105 is no, the first sampling point is still retained. It should be noted that not retaining the second sampling point and the first sampling point does not mean that the two sampling points are deleted, but they are not currently retained, and may be retained later. After the determination result is no, the absolute value of the difference between the third sampling point and the first sampling point is calculated next, and it is determined whether to retain the third sampling point and the second sampling point based on the absolute value. If the determination result is yes, step 106 is executed. If the result of the determination is no, the value of f is updated to 3, and the absolute value of the difference between the fourth sampling point and the first sampling point is calculated, and whether to retain the fourth sampling point and the fifth sampling point is determined according to the absolute value of the difference. Similarly, if it is determined that the corresponding sampling point and the previous sampling point need to be retained, step 106 is executed.

[0122] Step 106, taking the i+fth sampling point as the updated first reference point, and returning to step 103, until the first absolute value of the difference between the m-1th sampling point and the first reference point is obtained and determining whether to retain the m-1th sampling point and the m-2th sampling point according to the first absolute value.

[0123] For example, the first sampling point is currently used as the first reference point. If the determination result of step 105 is yes, then step 106 uses the second sampling point as the first reference point and executes the operation of step 105. If the determination result is still yes, then the third sampling point is used as the first reference point and the operation of step 105 is executed; if the determination result becomes no, then the first absolute value of the difference between the fifth sampling point and the third sampling point currently used as the first reference point can be obtained, and it is determined whether to retain the fifth sampling point according to the first absolute value. If the determination result is yes, then the fifth sampling point is updated as the first reference point in the next step.

[0124] This is done until the absolute value between the second to last sampling point and the first reference point is obtained, and then it is determined whether to retain the second to last sampling point and the third to last sampling point according to the absolute value.

[0125] Step 107, and use the curve formed by all the retained sampling points as the filtered real-time mechanical characteristic curve.

[0126] That is to say, the dotted line formed by all the sampling points that have been subjected to the retention operation is used as the real-time characteristic curve after filtering.

[0127] Step 108 , determining the similarity between the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve, and determining whether the monitored component fails based on the similarity.

[0128] Specifically, when the similarity is 100%, it indicates that the monitored component has no fault; when the similarity is less than or equal to a threshold, it indicates that the monitored component has fault.

[0129] Optionally, the reference mechanical characteristic curve of this embodiment is also generated through filtering operations such as steps 101 to 106. Specifically, it is as follows:

[0130] Obtaining a reference mechanical characteristic curve of the monitored component under normal operating conditions, the reference operating curve having n sampling points;

[0131] The first sampling point and the nth sampling point of the reference mechanical characteristic curve are retained;

[0132] The first sampling point of the reference mechanical characteristic curve is used as the initial second reference point;

[0133] Assign the value of s to 1;

[0134] Obtaining an absolute value of a difference between a j+sth sampling point in the reference mechanical characteristic curve and a second reference point as a second absolute value, wherein the jth sampling point represents the second reference point;

[0135] Determine whether the absolute value corresponding to the j+sth sampling point is greater than or equal to a threshold value, and if the determination result is yes, retain the j+sth sampling point and the j+s-1th sampling point;

[0136] Determine whether to retain the j+sth sampling point and the j+s-1th sampling point according to the second absolute value; if the determination result is yes, use the j+sth sampling point as the updated second reference point, and return to execute the operation of assigning the value of s to 1, until the first absolute value of the difference between the n-1th sampling point and the first reference point is obtained and determine whether to retain the n-1th sampling point and the n-2th sampling point according to the first absolute value;

[0137] The curve formed by all the retained sampling points is used as the final reference mechanical characteristic curve.

[0138] Wherein determining whether to retain the j+sth sampling point and the j+s-1th sampling point according to the second absolute value includes:

[0139] Determine whether the second absolute value corresponding to the j+sth sampling point is greater than or equal to a filtering threshold;

[0140] If the judgment result is yes, the j+sth sampling point and the j+s-1th sampling point are retained.

[0141] In this way, the data volume of the reference mechanical characteristic curve generated by the filtering operation will also be reduced. The process of processing the reference operation curve is actually similar to the process of filtering the real-time mechanical characteristic curve, both of which are for retaining characteristic points on the basis of reducing the data volume.

[0142] According to the method for online monitoring of switchgear of this embodiment, by filtering the real-time mechanical characteristic curve, data preprocessing is realized, which can reduce the amount of data calculation, is beneficial to subsequent data processing, and occupies little data memory. In addition, since the similarity of the curves is compared, it is not affected by whether the number of sampling points of the compared curves is the same, whether there is a delay, and whether the horizontal coordinates are consistent.

[0143] Embodiment 2

[0144] This embodiment further supplements the method for online monitoring of switchgear in the first embodiment.

[0145] like Figure 2 As shown, the method for online monitoring of a switchgear in this embodiment includes:

[0146] Step 200: acquiring a real-time mechanical characteristic curve of a monitored component, wherein the monitored component has a preset reference mechanical characteristic curve, and the real-time mechanical characteristic curve has m sampling points.

[0147] This step is the same as step 101 and will not be described again here.

[0148] In this embodiment, the reference mechanical characteristic curve may be generated in the following manner:

[0149] Obtaining a reference operating curve of the monitored component under normal working conditions, the reference mechanical characteristic curve having n sampling points;

[0150] The first sampling point and the nth sampling point of the reference mechanical characteristic curve are retained;

[0151] The first sampling point of the reference mechanical characteristic curve is used as the initial second reference point;

[0152] Assign the value of s to 1;

[0153] Obtaining an absolute value of a difference between a j+sth sampling point in the reference mechanical characteristic curve and a second reference point as a second absolute value, wherein the jth sampling point represents the second reference point;

[0154] It is determined whether to retain the j+sth sampling point and the j+s-1th sampling point according to the second absolute value. If the determination result is yes, the j+sth sampling point is used as the updated second reference point, and the operation of assigning the value of f to 1 is returned to be executed until the first absolute value of the difference between the n-1th sampling point and the first reference point is obtained and it is determined whether to retain the n-1th sampling point and the n-2th sampling point according to the first absolute value, and the curve formed by all the retained sampling points is used as the final reference mechanical characteristic curve.

[0155] Optionally, determining whether to retain the j+s th sampling point and the j+s-1 th sampling point according to the second absolute value includes:

[0156] Determine whether the second absolute value corresponding to the j+sth sampling point is greater than or equal to a filtering threshold;

[0157] If the judgment result is yes, the j+sth sampling point and the j+s-1th sampling point are retained.

[0158] How to generate the reference mechanical characteristic curve is consistent with the above-mentioned embodiment and will not be described in detail here.

[0159] Step 201 , retain the first sampling point and the mth sampling point of the real-time mechanical characteristic curve, and execute step 202 .

[0160] This step is consistent with step 101 and will not be repeated here.

[0161] Step 202 , taking the first sampling point of the real-time mechanical characteristic curve as the initial first reference point, and executing step 203 .

[0162] This step is consistent with step 102 and will not be described again here.

[0163] Step 203, assign the value of f to 1.

[0164] The order of step 203 and the above steps can be adjusted, and this embodiment only shows one order.

[0165] Step 204 , obtaining the absolute value of the difference between the i+f th sampling point in the real-time mechanical characteristic curve and the first reference point as the first absolute value, and executing step 205 .

[0166] Among them, the i-th sampling point represents the first reference point, and the value of f is initially 1.

[0167] This step is consistent with step 104 and will not be described again here.

[0168] Step 205 , determining whether to retain the i+f th sampling point and the i+f-1 th sampling point according to the first absolute value, if the determination result is yes, executing step 206 , if the determination result is no, executing step 208 .

[0169] This step is consistent with step 105 and will not be repeated here.

[0170] Step 206, if it is determined that the absolute value of the difference between the m-1th sampling point and the first reference point has been obtained as the first absolute value and the m-1th sampling point and the m-2th sampling point are retained according to the first absolute value, then step 209 is executed; otherwise, step 207 is executed.

[0171] There are many ways to determine whether the first absolute value of the difference between the m-1th sampling point and the first reference point has been obtained and whether to retain the m-1th sampling point and the m-2th sampling point according to the first absolute value. For example, directly determine whether the i+fth sampling point in the last execution of step 203 is the m-1th sampling point; or determine whether the first reference point updated in step 207 is the m-1th point. If it is determined to be the m-1th point, it can be determined to obtain the absolute value of the difference between the m-1th sampling point and the first reference point as the first absolute value. Of course, there can be other ways, which can be determined according to actual needs.

[0172] Step 207 , taking the (i+f)th sampling point as the updated first reference point, and returning to step 203 .

[0173] For example, if the current first reference point is the first sampling point, then step 207 is to use the second sampling point as the updated first reference point, and then return to the operation of step 204, that is, to use the absolute value of the difference between the third sampling point and the second sampling point as the first absolute value, and continue to execute step 205. It should be noted that there is no order between step 207 and step 206. For example, the operation of using the i+fth sampling point as the updated first reference point in step 207 can be executed first, and step 206 can be executed immediately. Then, it is determined whether to execute step 204 or step 209 according to the determination result. The specific setting can be based on actual needs.

[0174] Step 208 , update the value of f to f+1, and return to execute step 204 .

[0175] For example, if step 204 is to obtain the absolute value of the difference between the second sampling point and the first sampling point in the real-time mechanical characteristic curve, and the determination result in step 205 is no, then step 207 obtains the absolute value of the difference between the third sampling point and the first sampling point in the real-time mechanical characteristic curve and executes step 205. If the determination result is still no, then the absolute value of the difference between the lower four sampling points and the first sampling point in the real-time mechanical characteristic curve is obtained and step 205 is executed. If it is determined that the third sampling point and the second sampling point need to be retained based on the absolute value of the difference between the third sampling point and the first sampling point, step 206 is executed to use the third sampling point in the real-time mechanical characteristic curve as the first reference point, and obtain the absolute value of the difference between the fourth sampling point and the third sampling point, and then continue to determine whether to retain the fourth sampling point and the third sampling point. And so on.

[0176] Step 209 , taking the curve formed by all the retained sampling points as the filtered real-time mechanical characteristic curve, and executing step 210 .

[0177] Step 210, determine the first minimum Euclidean distance between each sampling point of the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve. If the first minimum Euclidean distance is greater than or equal to a first preset threshold, determine the sampling point corresponding to the first minimum Euclidean distance as the first recording point, obtain a first weight value according to the number of first recording points and the minimum Euclidean distance corresponding to each first recording point, and execute step 211.

[0178] The first minimum Euclidean distance between a sampling point of the real-time mechanical characteristic curve and the reference mechanical characteristic curve can be obtained in the following manner: the Euclidean distances between the sampling point on the real-time mechanical characteristic curve and each sampling point on the reference mechanical characteristic curve are obtained, and the smallest one is selected as the first minimum Euclidean distance between the sampling point and the reference mechanical characteristic curve. Each sampling point of the real-time mechanical characteristic curve corresponds to a first minimum Euclidean distance.

[0179] The first preset threshold can be determined according to actual needs and will not be elaborated here.

[0180] In this embodiment, the first weight value dW1 may be determined by using the following formula:

[0181] Wherein, t represents the number of first recording points, w(t) is a function related to t, and Ep represents the minimum Euclidean distance corresponding to the pth first recording point. Optionally, w(t)=1 / t.

[0182] Step 211, determine the second minimum Euclidean distance between each sampling point of the reference mechanical characteristic curve and the filtered real-time mechanical characteristic curve. If the second minimum Euclidean distance is greater than or equal to a second preset threshold, determine the sampling point corresponding to the second minimum Euclidean distance as the second recording point, obtain a second weight value according to the number of second recording points and the minimum Euclidean distance corresponding to each second recording point, and execute step 212.

[0183] The second minimum Euclidean distance between a sampling point of the reference mechanical characteristic curve and the real-time mechanical characteristic curve can be obtained in the following manner: obtain the Euclidean distances between the sampling point on the reference mechanical characteristic curve and each sampling point on the real-time mechanical characteristic curve, and select the smallest one as the second minimum Euclidean distance between the sampling point and the real-time mechanical characteristic curve. Each sampling point of the reference mechanical characteristic curve corresponds to a second minimum Euclidean distance.

[0184] In this embodiment, the second weight value dw2 may be determined by using the following formula:

[0185] Wherein, k represents the number of second recording points, w(k) is a function related to k, and Eq represents the minimum Euclidean distance corresponding to the qth second recording point. This w(k)=1 / k.

[0186] It should be noted that there is no sequence between step 210 and step 211. Step 210 may be performed first and then step 211, or step 210 may be performed first and then step 211, or they may be performed simultaneously. The details will not be repeated here.

[0187] Step 212 , determining the similarity between the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve according to the first weight value and the second weight value, and executing step 213 .

[0188] For example, the larger of the first weight value and the second weight value is used as the comparison weight value. If the comparison weight value is 0, the similarity is 100%. If the comparison weight value is greater than or equal to a third preset threshold, the similarity is 0. If the comparison weight value is greater than 0 and less than the third preset threshold, a linear fit is performed based on the weight values ​​of the real-time mechanical characteristic curve and the reference mechanical characteristic curve to obtain a curve between the similarity and the weight value, and then the similarity is determined based on the curve and the weight. The specific linear fitting method belongs to the prior art and will not be repeated here. For example, the horizontal axis of a coordinate system can be set to the similarity, and the vertical axis of a coordinate system can be set to the comparison weight value, the similarity is 0, the comparison weight value is the third preset threshold as one end of a line segment, the similarity is 100%, and the comparison weight value is 0 as the other end of a line segment. When the comparison weight value is greater than 0 and less than the third preset threshold, the similarity is determined based on the line segment on the coordinate system.

[0189] Step 213: Determine whether the monitored component fails based on the similarity.

[0190] For example, if the similarity is 100%, then the monitored component has no fault. If the similarity is 0 or less than a threshold, then the monitored component has a fault. The threshold here can be set according to actual needs.

[0191] In practical applications, if the monitored component is a ground switch of a switch cabinet, after filtering operations from step 201 to step 209, the sampling points of its real-time mechanical characteristic curve can be reduced from more than 20,000 to more than 1,000, which greatly reduces subsequent processing operations.

[0192] In this embodiment, by calculating the weighted distance of the data, the abnormal points of the data can be selected more sensitively, and then the abnormal state of the monitored components can be accurately judged based on these abnormal points to avoid omissions. Secondly, since multiple abnormal points are weighted, the superposition effect is closer to the real result, and the result deviation will not be large due to the uncertainty of a single abnormal point.

[0193] Embodiment 3

[0194] This embodiment provides an apparatus for online monitoring of a switchgear, which is used to execute the method for online monitoring of a switchgear of the first embodiment. The apparatus for online monitoring of a switchgear may be integrated into a relay protection device or may be separately provided, which is not limited here.

[0195] like Figure 3, which is a schematic diagram of the structure of the device for online monitoring of switchgear according to the present embodiment. The device for online monitoring of switchgear comprises a first acquisition unit 300, a reservation unit 301, an initial reference point unit 302, an assignment unit 303, a second acquisition unit 304, a first determination unit 305, a first update unit 306, a formation unit 307 and a second determination unit 308.

[0196] The first acquisition unit 300 is used to acquire a real-time mechanical characteristic curve of a monitored component, wherein the real-time mechanical characteristic curve has a total of m sampling points, and the monitored component has a preset reference mechanical characteristic curve, which is acquired by the monitored component under normal working conditions; the retention unit 301 is used to retain the 1st sampling point and the mth sampling point of the real-time mechanical characteristic curve; the initial reference point unit 302 is used to use the 1st sampling point of the real-time mechanical characteristic curve as the initial first reference point; the assignment unit 303 is used to assign the value of f to 1; the second acquisition unit 304 is used to acquire the absolute value of the difference between the i+fth sampling point in the real-time mechanical characteristic curve and the first reference point as the first absolute value, wherein the ith sampling point represents the first reference point; the first determination unit 305 is used to determine the absolute value of the difference between the i+fth sampling point and the first reference point in the real-time mechanical characteristic curve as the first absolute value. The first updating unit 306 is used to determine whether to retain the i+fth sampling point and the i+f-1th sampling point according to the first absolute value, and if the determination result is yes, a first updating unit 306 is triggered; the first updating unit 306 is used to use the i+fth sampling point as the updated first reference point, and trigger the assignment unit 303 until the absolute value of the difference between the m-1th sampling point and the first reference point is obtained as the first absolute value and whether to retain the m-1th sampling point and the m-2th sampling point is determined according to the first absolute value; the constituting unit 307 is used to use the curve constituted by all the retained sampling points as the filtered real-time mechanical characteristic curve; the second determining unit 308 is used to determine the similarity between the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve, and determine whether the monitored component has a fault according to the similarity.

[0197] Optionally, the reference characteristic curve may be pre-stored in the second determination unit 308, or may be pre-stored in other storages, as long as the second determination unit can obtain it when needed.

[0198] Alternatively, if Figure 3 As shown, the device of this embodiment further includes a second updating unit 309. When the determination result of the first determining unit 305 is no, the second updating unit 309 is used to update the value of f to f+1 and then trigger the second acquiring unit 304.

[0199] Optionally, the first acquisition unit 300 of this embodiment is further used to acquire the original reference mechanical characteristic curve of the monitored component under normal working conditions, and the reference mechanical characteristic curve has n sampling points; the retention unit 301 is further used to retain the first sampling point and the nth sampling point of the reference mechanical characteristic curve; the initial reference point unit 302 is further used to use the first sampling point of the reference mechanical characteristic curve as the initial second reference point; the assignment unit 303 is further used to assign the value of s to 1; the second acquisition unit 304 is further used to acquire the absolute value of the difference between the j+sth sampling point and the second reference point in the reference mechanical characteristic curve as the second absolute value, wherein the jth sampling point is the first sampling point and the nth sampling point of the reference mechanical characteristic curve. The sample point represents the second reference point; the first determining unit 305 is further used to determine whether to retain the j+sth sampling point and the j+s-1th sampling point according to the second absolute value, and if the determination result is yes, trigger the first updating unit 306; the first updating unit 306 is further used to use the j+sth sampling point as the updated second reference point, and trigger the assignment 303 until the first absolute value of the difference between the n-1th sampling point and the first reference point is obtained and whether to retain the n-1th sampling point and the n-2th sampling point is determined according to the first absolute value; the constituting unit 307 is further used to use the curve constituted by all the retained sampling points as the final reference mechanical characteristic curve.

[0200] Optionally, the first determining unit 305 is specifically configured to:

[0201] Determine whether the second absolute value corresponding to the j+sth sampling point is greater than or equal to a filtering threshold;

[0202] If the judgment result is yes, then the j+sth sampling point and the j+s-1th sampling point are retained.

[0203] Optionally, the first determining unit 305 is specifically configured to:

[0204] Determine whether the absolute value corresponding to the i+fth sampling point is greater than or equal to a filtering threshold;

[0205] If the determination result is yes, the i+fth sampling point and the i+f-1th sampling point are retained.

[0206] The working methods of each unit in this embodiment are the same as those in the previous embodiment and will not be described again here.

[0207] It can be understood that, when receiving the data of the corresponding curve, each of the above units will process the data of the corresponding curve.

[0208] According to the device for online monitoring of switchgear of this embodiment, by filtering the real-time mechanical characteristic curve, data preprocessing is realized, which can reduce the amount of data calculation, is beneficial to subsequent data processing, and occupies little data memory. In addition, since the similarity of the curves is compared, it is not affected by whether the number of sampling points of the compared curves is the same, whether there is a delay, and whether the horizontal coordinates are consistent.

[0209] Embodiment 4

[0210] This embodiment further supplements the device for online monitoring of switchgear in the third embodiment.

[0211] like Figure 4 , which is a schematic diagram of the structure of the device for online monitoring of switchgear according to this embodiment. The second determining unit 308 of this embodiment specifically includes a first determining subunit 3081, a second determining subunit 3082, a first acquiring subunit 3083, a third determining subunit 3084, a fourth determining subunit 3085, a second acquiring subunit 3086 and a fifth determining subunit 3087.

[0212] Among them, the first determination subunit 3081 is used to determine the first minimum Euclidean distance between each sampling point of the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve; the second determination subunit 3082 is used to determine the sampling point corresponding to the first minimum Euclidean distance as the first recording point if the first minimum Euclidean distance is greater than or equal to a first preset threshold; the first acquisition subunit 3083 is used to obtain a first weight value according to the number of first recording points and the minimum Euclidean distance corresponding to each first recording point; the third determination subunit 3084 is used to determine the second minimum Euclidean distance between each sampling point of the filtered reference mechanical characteristic curve and the real-time mechanical characteristic curve; the fourth determination subunit 3085 is used to determine the sampling point corresponding to the second minimum Euclidean distance as the second recording point if the second minimum Euclidean distance is greater than or equal to a second preset threshold; the second acquisition subunit 3086 is used to obtain a second weight value according to the number of second recording points and the minimum Euclidean distance corresponding to each second recording point; the fifth determination subunit 3087 is used to determine the similarity between the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve according to the first weight value and the second weight value.

[0213] Optionally, the first acquisition subunit 3083 is specifically used for:

[0214] The first weight value dW1 is determined according to the following formula:

[0215] Wherein, t represents the number of first record points, w(t) is a function related to t, and Ep represents the minimum Euclidean distance corresponding to the pth first record point;

[0216] The second acquisition subunit 3086 is specifically used for:

[0217] The second weight value dw2 is determined according to the following formula:

[0218] Wherein, k represents the number of second record points, w(k) is a function related to k, and Eq represents the minimum Euclidean distance corresponding to the qth second record point.

[0219] Optionally, w(t)=1 / t, w(k)=1 / k.

[0220] In this embodiment, by calculating the weighted distance of the data, the abnormal points of the data can be selected more sensitively, and then the abnormal state of the monitored components can be accurately judged based on these abnormal points to avoid omissions. Secondly, since multiple abnormal points are weighted, the superposition effect is closer to the real result, and the result deviation will not be large due to the uncertainty of a single abnormal point.

[0221] The present invention also provides a device for online monitoring of a switchgear, wherein the switchgear includes a plurality of monitored components, and the device includes at least one memory and at least one processor. The memory is used to store instructions. The processor is used to execute the method for online monitoring of a switchgear described in any of the above embodiments according to the instructions stored in the memory.

[0222] An embodiment of the present invention further provides a readable storage medium in which machine-readable instructions are stored. When the machine-readable instructions are executed by a machine, the machine executes the method for online monitoring of a switchgear described in any of the above embodiments.

[0223] The readable medium stores machine-readable instructions, which, when executed by the processor, cause the processor to execute any of the aforementioned methods. Specifically, a system or device equipped with a readable storage medium may be provided, on which a software program code implementing the functions of any of the above-mentioned embodiments is stored, and a computer or processor of the system or device reads and executes the machine-readable instructions stored in the readable storage medium.

[0224] In this case, the program code itself read from the machine-readable medium can realize the function of any one of the above-mentioned embodiments, and thus the machine-readable code and the machine-readable storage medium storing the machine-readable code constitute a part of the present invention.

[0225] Examples of readable storage media include floppy disks, hard disks, magneto-optical disks, optical disks (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), magnetic tapes, non-volatile memory cards, and ROMs. Alternatively, the program code may be downloaded from a server computer or a cloud via a communication network.

[0226] Those skilled in the art should understand that the various embodiments disclosed above can be modified and altered in various ways without departing from the essence of the invention. Therefore, the protection scope of the present invention should be defined by the appended claims.

[0227] It should be noted that not all steps and units in the above-mentioned processes and system structure diagrams are necessary, and some steps or units can be ignored according to actual needs. The execution order of each step is not fixed and can be adjusted as needed. The device structure described in the above-mentioned embodiments can be a physical structure or a logical structure, that is, some units may be implemented by the same physical entity, or some units may be implemented by multiple physical entities, or some components in multiple independent devices may be implemented together.

[0228] In the above embodiments, the hardware unit can be realized by mechanical means or electrical means. For example, a hardware unit or a processor can include permanent dedicated circuits or logic (such as special processors, FPGA or ASIC) to complete the corresponding operation. The hardware unit or the processor can also include programmable logic or circuits (such as general-purpose processors or other programmable processors), which can be temporarily set by software to complete the corresponding operation. Concrete implementation (mechanical means or dedicated permanent circuits or temporarily set circuits) can be determined based on cost and time considerations.

[0229] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for online monitoring of a switchgear, comprising: A real-time mechanical characteristic curve of a monitored component is obtained, wherein the real-time mechanical characteristic curve has a total of m sampling points, and the monitored component has a preset reference mechanical characteristic curve, wherein the reference mechanical characteristic curve is obtained when the monitored component is in a normal working state, and the method further comprises: Retaining the first sampling point and the mth sampling point of the real-time mechanical characteristic curve; Taking the first sampling point of the real-time mechanical characteristic curve as the initial first reference point; Assign the value of f to 1; Obtaining an absolute value of a difference between an i+fth sampling point in the real-time mechanical characteristic curve and the first reference point as a first absolute value, wherein the i-th sampling point represents the first reference point; determining whether to retain the i+fth sampling point and the i+f-1th sampling point according to the first absolute value; If the result of the determination is yes, the i+fth sampling point is used as the updated first reference point, and the operation of assigning the value of f to 1 is returned to execute, until the absolute value of the difference between the m-1th sampling point and the first reference point is obtained as the first absolute value, and it is determined whether to retain the m-1th sampling point and the m-2th sampling point according to the first absolute value; The curve formed by all the retained sampling points is used as the filtered real-time mechanical characteristic curve; Determining the similarity between the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve, and determining whether the monitored component fails based on the similarity; Determining the similarity between the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve includes: determining a first minimum Euclidean distance between each sampling point of the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve; If a first minimum Euclidean distance is greater than or equal to a first preset threshold, determining the sampling point corresponding to the first minimum Euclidean distance as the first recording point; Obtaining a first weight value according to the number of the first recording points and the minimum Euclidean distance corresponding to each of the first recording points; determining a second minimum Euclidean distance between each sampling point of the reference mechanical characteristic curve and the filtered real-time mechanical characteristic curve; If the second minimum Euclidean distance is greater than or equal to a second preset threshold, determining the sampling point corresponding to the second minimum Euclidean distance as the second recording point; Obtaining a second weight value according to the number of the second recording points and the minimum Euclidean distance corresponding to each of the second recording points; determining a similarity between the filtered real-time mechanical characteristic curve and a reference mechanical characteristic curve according to the first weight value and the second weight value; The first weight value dW1 is determined according to the following formula: Wherein, t represents the number of first record points, w(t) is a function related to t, and Ep represents the minimum Euclidean distance corresponding to the pth first record point; The second weight value dw2 is determined according to the following formula: Wherein, k represents the number of second record points, w(k) is a function related to k, and Eq represents the minimum Euclidean distance corresponding to the qth second record point.

2. The method according to claim 1, characterized in that Also includes: If the determination result is no, after updating the value of f to f+1, the process returns to executing the operation of obtaining the absolute value of the difference between the i+fth sampling point in the real-time mechanical characteristic curve and the first reference point as the first absolute value.

3. The method according to claim 1, characterized in that Before obtaining the absolute value of the difference between the i+fth sampling point in the real-time mechanical characteristic curve and the first reference point as the first absolute value, the method further includes: Obtaining an original reference mechanical characteristic curve of the monitored component under normal working conditions, the reference mechanical characteristic curve having n sampling points; The first sampling point and the nth sampling point of the reference mechanical characteristic curve are retained; The first sampling point of the reference mechanical characteristic curve is used as the initial second reference point; Assign the value of s to 1; Obtaining an absolute value of a difference between a j+sth sampling point in the reference mechanical characteristic curve and the second reference point as a second absolute value, wherein the jth sampling point represents the second reference point; determining whether to retain the j+sth sampling point and the j+s-1th sampling point according to the second absolute value; If the result of the determination is yes, the j+sth sampling point is used as the updated second reference point, and the operation of assigning the value of s to 1 is returned to execute until the first absolute value of the difference between the n-1th sampling point and the first reference point is obtained and it is determined whether to retain the n-1th sampling point and the n-2th sampling point according to the first absolute value; The curve formed by all the retained sampling points is used as the final reference mechanical characteristic curve.

4. The method according to claim 3, characterized in that Determining whether to retain the j+sth sampling point and the j+s-1th sampling point according to the second absolute value includes: Determine whether the second absolute value corresponding to the j+sth sampling point is greater than or equal to a filtering threshold; If the judgment result is yes, the j+sth sampling point and the j+s-1th sampling point are retained.

5. The method according to claim 1, characterized in that Determining whether to retain the i+fth sampling point and the i+f-1th sampling point according to the absolute value includes: Determine whether the absolute value corresponding to the i+fth sampling point is greater than or equal to a filtering threshold; If the determination result is yes, the i+fth sampling point and the i+f-1th sampling point are retained.

6. The method according to claim 1, characterized in that w(t)=1 / t, w(k)=1 / k.

7. Devices for online monitoring of switchgear, including: A first acquisition unit, used for acquiring a real-time mechanical characteristic curve of a monitored component, the real-time mechanical characteristic curve having a total of m sampling points, the monitored component having a preset reference mechanical characteristic curve, the reference mechanical characteristic curve being acquired when the monitored component is in a normal working state; It is characterized in that it also includes: A retaining unit, used for retaining the first sampling point and the mth sampling point of the real-time mechanical characteristic curve; An initial reference point unit, used for taking the first sampling point of the real-time mechanical characteristic curve as an initial first reference point; An assignment unit, used to assign the value of f to 1; a second acquisition unit, configured to acquire an absolute value of a difference between an i+fth sampling point in the real-time mechanical characteristic curve and the first reference point as a first absolute value, wherein the ith sampling point represents the first reference point; a first determining unit, configured to determine whether to retain the i+fth sampling point and the i+f-1th sampling point according to the first absolute value, and trigger a first updating unit if the determination result is yes; The first updating unit is used to use the i+fth sampling point as the updated first reference point and trigger the assignment unit until the absolute value of the difference between the m-1th sampling point and the first reference point is obtained as the first absolute value and whether to retain the m-1th sampling point and the m-2th sampling point is determined according to the first absolute value; A composition unit, used for taking a curve composed of all the retained sampling points as a filtered real-time mechanical characteristic curve; a second determination unit, configured to determine a similarity between the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve, and determine whether the monitored component fails according to the similarity; The second determining unit specifically includes: a first determining subunit, configured to determine a first minimum Euclidean distance between each sampling point of the filtered real-time mechanical characteristic curve and the reference mechanical characteristic curve; a second determining subunit, configured to determine, if a first minimum Euclidean distance is greater than or equal to a first preset threshold, a sampling point corresponding to the first minimum Euclidean distance as a first recording point; a first acquisition subunit, configured to acquire a first weight value according to the number of the first recording points and the minimum Euclidean distance corresponding to each of the first recording points; a third determination subunit, configured to determine a second minimum Euclidean distance between each sampling point of the reference mechanical characteristic curve and the filtered real-time mechanical characteristic curve; a fourth determining subunit, configured to determine, if a second minimum Euclidean distance is greater than or equal to a second preset threshold, a sampling point corresponding to the second minimum Euclidean distance as a second recording point; a second acquisition subunit, configured to acquire a second weight value according to the number of the second recording points and the minimum Euclidean distance corresponding to each of the second recording points; a fifth determining subunit, configured to determine a similarity between the filtered real-time mechanical characteristic curve and a reference mechanical characteristic curve according to the first weight value and the second weight value; The first acquisition subunit is specifically used for: The first weight value dW1 is determined according to the following formula: Wherein, t represents the number of first record points, w(t) is a function related to t, and Ep represents the minimum Euclidean distance corresponding to the pth first record point; The second acquisition subunit is specifically used for: The second weight value dw2 is determined according to the following formula: Wherein, k represents the number of second record points, w(k) is a function related to k, and Eq represents the minimum Euclidean distance corresponding to the qth second record point.

8. The device according to claim 7, characterized in that Also includes: A second updating unit is used to update the value of f to f+1 and then trigger the second acquiring unit.

9. The device according to claim 7, characterized in that The first acquisition unit is also used to acquire an original reference mechanical characteristic curve of the monitored component under normal working conditions, the reference mechanical characteristic curve having n sampling points; The retaining unit is also used to retain the first sampling point and the nth sampling point of the reference mechanical characteristic curve; The initial reference point unit is also used to use the first sampling point of the reference mechanical characteristic curve as the initial second reference point; The assignment unit is also used to assign the value of s to 1; The second acquisition unit is further used to acquire an absolute value of a difference between a j+sth sampling point in the reference mechanical characteristic curve and the second reference point as a second absolute value, wherein the jth sampling point represents the second reference point; The first determining unit is further used to determine whether to retain the j+sth sampling point and the j+s-1th sampling point according to the second absolute value, and if the determination result is yes, trigger the first updating unit; The first updating unit is further used to use the j+sth sampling point as the updated second reference point and trigger the assignment unit until a first absolute value of a difference between the n-1th sampling point and the first reference point is obtained and whether to retain the n-1th sampling point and the n-2th sampling point is determined according to the first absolute value; The forming unit is further used to use the curve formed by all the retained sampling points as the final reference mechanical characteristic curve.

10. The device according to claim 9, characterized in that The first determining unit is specifically configured to: Determine whether the second absolute value corresponding to the j+sth sampling point is greater than or equal to a filtering threshold; If the judgment result is yes, the j+sth sampling point and the j+s-1th sampling point are retained.

11. The device according to claim 7, characterized in that The first determining unit is specifically configured to: Determine whether the absolute value corresponding to the i+fth sampling point is greater than or equal to a filtering threshold; If the determination result is yes, the i+fth sampling point and the i+f-1th sampling point are retained.

12. A device for online monitoring of a switchgear, the switchgear comprising a plurality of monitored components, characterized in that: The device comprises: at least one memory for storing instructions; At least one processor is configured to execute the method for online monitoring of a switchgear according to any one of claims 1 to 6 according to the instructions stored in the memory.

13. A readable storage medium, characterized in that: The readable storage medium stores machine-readable instructions. When the machine-readable instructions are executed by a machine, the machine executes the method for online monitoring of a switchgear according to any one of claims 1 to 6.

Images