An intelligent monitoring method and system for a skid-mounted electric control integrated substation

Abstract

The present invention relates to the technical field of measuring and analyzing electrical variables, and proposes an intelligent monitoring method and system for a skid-mounted integrated electric control substation, comprising: in the skid-mounted integrated electric control substation, a distributed multi-domain intelligent management system is configured, and when the monitoring unit in the multi-domain intelligent management system is used to monitor the status of the circuit breaker in the gas-insulated switchgear and the air-insulated switchgear in the skid-mounted integrated electric control substation, the electrical parameter data of the circuit breaker in the operation process can be obtained in real time, and by in-depth analysis of the operating parameters during the opening and closing operations of the circuit breaker, an effective response can be made in time to the possible faults of the circuit breaker in the gas-insulated switchgear and the air-insulated switchgear in the substation, so as to ensure the safe and stable operation of the power system.

Description

Technical Field

[0001] The present invention relates to the technical field of measuring electric variable analysis, and in particular to an intelligent monitoring method and system for a skid-mounted electric-control integrated substation. Background Art

[0002] The skid-mounted integrated electric control substation is an intelligent substation that supports real-time automatic control, intelligent regulation, online analysis and decision-making of the power grid. It has been widely used in scenarios such as oil and gas stations. The monitoring of the skid-mounted integrated electric control substation can be configured with a distributed multi-domain intelligent management system. The distributed multi-domain intelligent management system can collect and monitor the substation, protection and control equipment in real time, and monitor, manage and control the internal operation and maintenance environment and safety status of the substation in real time, so as to realize timely early warning of abnormalities and faults. The application of the distributed multi-domain intelligent management system has greatly improved the reliability, safety, real-time performance and ease of use of the substation system of the skid-mounted integrated electric control substation, while reducing the occurrence of faults and effectively reducing the workload of operation and maintenance personnel.

[0003] During the operation of the skid-mounted integrated electric control substation, the operating status data of the circuit breakers in the skid-mounted integrated electric control substation is monitored and analyzed in real time, which can timely discover potential faults in the circuit breakers, realize remote operation and maintenance of the circuit breakers, improve the safety and reliability of the circuit breakers, and enhance the operation and maintenance management efficiency of the skid-mounted integrated electric control substation.

[0004] Generally, the current signal of a circuit breaker in normal operation has a specific waveform with five stages of change. The similarity between the current signal collected during the operation of the circuit breaker and the current signal in the normal operation of the circuit breaker can be used to monitor whether the circuit breaker has an operating mechanism failure. However, when the operating mechanism failure does not cause obvious changes in the current waveform, such as a failure in the opening and closing coil of the operating mechanism or a poor contact failure of the iron core when it is attracted, it is impossible to accurately detect the circuit breaker failure. Summary of the invention

[0005] The present invention provides an intelligent monitoring method and system for a skid-mounted electric control integrated substation to solve the problem of inaccurate fault detection and identification of circuit breakers with unclear current waveform changes. The technical solutions adopted are as follows:

[0006] In a first aspect, an embodiment of the present invention provides an intelligent monitoring method for a skid-mounted electric-control integrated substation, the method comprising the following steps:

[0007] During the opening and closing operation of the circuit breaker of the skid-mounted integrated electric control substation, current signals are collected, and a current sequence is obtained according to the current signals; during the opening and closing operation of the circuit breaker in normal operation, current signals of normal operation are collected, and a standard current sequence is obtained according to the current signals of normal operation; and according to the values ​​of the current signals, current transition moments in the collection moments corresponding to the current signals contained in the current sequence and the standard current sequence are respectively determined;

[0008] According to the difference in the change trend of the current signal before the current change moment at the acquisition moment contained in the current sequence and the standard current sequence, and the difference in the value of the current signal after the current change moment, the difference degree of the second stage of opening and closing of the current sequence is obtained;

[0009] Record any current signal included in the current sequence and the standard current sequence as the target current signal, determine the left local change trend and the right local change trend of the target current signal according to the change trend of the adjacent current signals in the local range of the sequence where the target current signal is located, determine the local change trend of the target current signal according to the difference between the left local change trend and the right local change trend of the target current signal, and obtain the second stage abnormality of the opening and closing of the current sequence according to the difference between the local change trends of the current signals included in the current sequence and the standard current sequence;

[0010] According to the difference degree of the second stage of opening and closing of the current sequence and the abnormality degree of the second stage of opening and closing, the fault detection result of the skid-mounted electric control integrated substation is obtained.

[0011] Furthermore, the current transition moments in the acquisition moments corresponding to the current signals included in the current sequence and the standard current sequence are determined according to the values ​​of the current signals, and the specific methods include:

[0012] Obtain all current peaks in the current sequence, and record the earliest acquisition time corresponding to the current peak as the current transition time of the current sequence;

[0013] All current peaks in the standard current sequence are obtained, and the earliest acquisition time corresponding to the current peak is recorded as the current transition time of the standard current sequence.

[0014] Further, the second stage difference degree of opening and closing of the current sequence is obtained according to the difference in the change trend of the current signal at the acquisition time before the current change time contained in the current sequence and the standard current sequence, and the difference in the value of the current signal after the current change time, including the specific method of:

[0015] With the current signal as the vertical axis and the collection time corresponding to the current signal as the horizontal axis, a plane rectangular coordinate system is established, and the points corresponding to all current signals whose collection time is before the current transformation time contained in the current sequence are marked, and straight line fitting is performed on all points to obtain a first fitting straight line, and the slope of the first fitting straight line is recorded as the pre-stroke stage trend of the current sequence, and the mean value of all current signals whose collection time is after the current transformation time contained in the current sequence is recorded as the core movement stage mean value of the current sequence;

[0016] Mark points corresponding to all current signals contained in the standard current sequence at the time of collection before the current transition moment in the plane rectangular coordinate system, perform straight line fitting on all points in the plane rectangular coordinate system to obtain a second fitting straight line, record the slope of the second fitting straight line as the pre-stroke stage trend of the standard current sequence, and record the mean value of all current signals contained in the standard current sequence at the time of collection after the current transition moment as the core movement stage mean value of the standard current sequence;

[0017] According to the difference between the trends of the pre-travel stage of the current sequence and the standard current sequence, and the difference between the mean values ​​of the core movement stage, the difference degree of the second stage of opening and closing of the current sequence is obtained.

[0018] Further, the second stage difference of the opening and closing of the current sequence is obtained according to the difference between the pre-travel stage trends of the current sequence and the standard current sequence, and the difference between the mean values ​​of the core movement stage, including the specific method of:

[0019] The absolute value of the difference between the trend of the pre-travel stage of the current sequence and the standard current sequence is recorded as the first absolute value of the current sequence; the absolute value of the difference between the mean value of the core movement stage of the current sequence and the standard current sequence is recorded as the second absolute value of the current sequence;

[0020] The linear normalized value of the sum of the first absolute value and the second absolute value of the current sequence is recorded as the difference degree of the second stage of opening and closing of the current sequence.

[0021] Further, the method of determining the left local change trend and the right local change trend of the target current signal according to the change trend of the adjacent current signals in the local range of the sequence where the target current signal is located includes the following specific methods:

[0022] In the sequence where the target current signal is located, the current signal at the first preset threshold number of acquisition moments before the acquisition moment corresponding to the target current signal is recorded as the previous adjacent signal of the target current signal, and the current signal at the first preset threshold number of acquisition moments after the acquisition moment corresponding to the target current signal is recorded as the subsequent adjacent signal of the target current signal;

[0023] According to the preceding adjacent signal and the following adjacent signal of the target current signal, a left local variation trend and a right local variation trend of the target current signal are determined.

[0024] Further, the method of determining the left local change trend and the right local change trend of the target current signal according to the front adjacent signal and the rear adjacent signal of the target current signal includes the following specific methods:

[0025] Perform straight line fitting on the previous adjacent signal of the target current signal and the acquisition time of the previous adjacent signal to obtain a third fitting straight line, and record the slope of the third fitting straight line as the left local change trend of the target current signal;

[0026] Perform straight-line fitting on the subsequent adjacent signal of the target current signal and the acquisition time of the subsequent adjacent signal to obtain a fourth fitting straight line, and record the slope of the fourth fitting straight line as the right local variation trend of the target current signal;

[0027] Further, the determining of the local variation trend of the target current signal includes the following specific methods:

[0028] The absolute value of the difference between the absolute values ​​of the left local change trend and the right local change trend of the target current signal is recorded as the third absolute value of the target current signal, and the linear normalized value of the third absolute value of the target current signal is recorded as the local change trend of the target current signal.

[0029] Further, the specific method of obtaining the abnormality degree of the second stage of the opening and closing of the current sequence includes:

[0030] The absolute value of the difference between the local change trends of the current signals at the same position in the current sequence and the standard current sequence is recorded as the fourth absolute value of the current signals at the same position, and the linear normalized value of the mean of the fourth absolute values ​​of all current signals at the same position in the current sequence and the standard current sequence is recorded as the second stage abnormality of the opening and closing of the current sequence.

[0031] Further, the fault detection result of the skid-mounted integrated electric control substation is obtained according to the difference degree of the second stage of the opening and closing of the current sequence and the abnormality degree of the second stage of the opening and closing, including the specific method of:

[0032] The product of the difference degree of the second stage of opening and closing of the current sequence and the abnormality degree of the second stage of opening and closing is recorded as the fault possibility of the current sequence;

[0033] When the fault probability of the current sequence is greater than or equal to a second preset threshold, it is determined that a circuit breaker fault occurs during the opening and closing operation of the circuit breaker of the skid-mounted electric-controlled integrated substation;

[0034] When the fault probability of the current sequence is less than the second preset threshold, it is determined that no circuit breaker fault occurs during the opening and closing operation of the circuit breaker of the skid-mounted electronically controlled integrated substation.

[0035] In the second aspect, an embodiment of the present invention further provides an intelligent monitoring system for a skid-mounted integrated electric-control substation, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements the steps of any one of the above-mentioned methods when executing the computer program.

[0036] The beneficial effects of the present invention are:

[0037] The present application divides the current transition moment according to the characteristic that the power gradually rises and then gradually falls in the pre-stroke stage and the core movement stage during the opening and closing operation. The current transition moment is the moment when the pre-stroke stage is changed to the core movement stage during the opening and closing operation. According to the characteristic that when a circuit breaker fault with unclear current waveform changes, such as coil circuit undervoltage, coil circuit overvoltage and coil aging, occurs, the current signal and the standard current signal will have different changing trends in the pre-stroke stage and the core movement stage, the possibility of circuit breaker fault occurrence is evaluated, and the difference degree of the second stage of opening and closing of the current sequence is obtained; in order to improve the comprehensiveness and accuracy of circuit breaker fault detection with unclear current waveform changes Accuracy, further consider the characteristics of the fault of poor core contact in the operating mechanism of the circuit breaker, that is, the current waveform of the circuit breaker of the skid-mounted integrated electric control substation does not change significantly, and only the characteristics of local current signal fluctuations will appear in the current sequence. Therefore, the difference in the significance of the change trend of the current signal contained in the current sequence and the standard current sequence in the local range is evaluated, and the abnormality of the second stage of opening and closing of the current sequence is obtained; finally, according to the difference degree of opening and closing of the second stage of the current sequence and the abnormality of opening and closing of the second stage, the fault detection result of the skid-mounted integrated electric control substation is obtained to solve the problem of inaccurate fault detection and identification of circuit breakers with unclear current waveform changes. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0039] Figure 1 A schematic flow chart of an intelligent monitoring method for a skid-mounted electric-control integrated substation provided by one embodiment of the present invention;

[0040] Figure 2A schematic diagram of the change phases of the current signal of the opening and closing operation provided by an embodiment of the present invention;

[0041] Figure 3 A schematic diagram of local current signal fluctuations provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] See also Figure 1 , which shows a flow chart of an intelligent monitoring method for a skid-mounted electric-control integrated substation provided by an embodiment of the present invention, the method comprising the following steps:

[0044] Step S001, collecting current signals during the opening and closing operations of the circuit breaker of the skid-mounted electrically-controlled integrated substation, obtaining a current sequence according to the current signals, collecting normal operating current signals during the opening and closing operations of the circuit breaker in normal operation, obtaining a standard current sequence according to the normal operating current signals, and determining current transition moments in the collection moments corresponding to the current signals contained in the current sequence and the standard current sequence according to the values ​​of the current signals.

[0045] The monitoring types of skid-mounted integrated electric control substation include but are not limited to fire monitoring, air conditioning control, temperature and humidity monitoring, lighting control, dehumidifier control, UPS monitoring, emergency lighting control, electric heater control, intelligent ventilation control, security control, SF6 gas monitoring, dry-type transformer monitoring, gas-insulated switchgear, air-insulated switchgear, main transformer monitoring, and high-voltage lightning arrester. Specifically, in the skid-mounted integrated electric control substation, a distributed multi-domain intelligent management system is configured, which covers multiple components such as emergency lighting system, fire monitoring system, HVAC system, security monitoring, sound and light alarm, dehumidifier, SF6 gas alarm, UPS power supply, dry-type transformer, gas-insulated switchgear online monitoring system, air-insulated switchgear online monitoring system, main transformer online monitoring system, and high-voltage lightning arrester online monitoring system.

[0046] Furthermore, as a key control and protection device of the skid-mounted integrated electric control substation, the circuit breaker's working state plays a direct and decisive role in the continuity and stability of the substation operation, and its state change is closely related to the state change of the entire substation. In the process of using the distributed multi-domain intelligent management system, the circuit breaker monitoring accuracy in the gas-insulated switchgear online monitoring system and the air-insulated switchgear online monitoring system provides strong support for the safe and stable operation of the entire substation.

[0047] When the monitoring unit in the multi-domain intelligent management system is used to monitor the status of the circuit breakers in the gas-insulated switchgear and air-insulated switchgear in the skid-mounted integrated electric control substation, the electrical parameter data of the circuit breaker during operation can be obtained in real time. Through in-depth analysis of the operating parameters during the circuit breaker opening and closing operations, effective responses can be made in a timely manner to possible faults in the gas-insulated switchgear and air-insulated switchgear in the substation to ensure the safe and stable operation of the power system.

[0048] Specifically, in the present application, during the opening and closing operation of the circuit breaker, the current signal of the circuit breaker in the gas-insulated switchgear and the air-insulated switchgear is collected by using the ammeter in the monitoring unit of the skid-mounted electric control integrated substation. The current signals of the circuit breakers during the opening and closing operation are arranged in the order of the collection time to obtain the current sequence.

[0049] During the opening and closing operation of the circuit breaker of the skid-mounted integrated electric control substation in normal operation, the current signal of the circuit breaker in the gas-insulated switchgear and air-insulated switchgear in normal operation is collected by using the ammeter in the monitoring unit of the skid-mounted integrated electric control substation. The current signals of the circuit breakers in normal operation during the opening and closing operation are arranged in the order of the collection time to obtain the standard current sequence.

[0050] Preferably, in one embodiment of the present application, the sampling frequency of the current signal of the circuit breaker is 5kHz, and the first current signal is collected from the beginning of the opening and closing operation until the end of the opening and closing operation. The current signal collection is stopped. In actual application, as other implementation methods, the implementer can decide the value of the sampling frequency of the current signal according to the actual situation, and this application does not impose any special restrictions.

[0051] It is understandable that both the current sequence and the standard current sequence are smoothed using a sliding average filter method to reduce the impact of noise in the collected current signal on subsequent analysis. Using a sliding average filter method to smooth the current sequence and the standard current sequence is a well-known technique and will not be described in detail.

[0052] When the circuit breaker of the skid-mounted integrated electric control substation is operated, the change of the current signal is usually divided into five stages: pre-travel stage, core movement stage, lock device action stage, continuous action stage, and current breaking stage. In the pre-travel stage, the circuit breaker's opening and closing command is issued, the coil begins to be energized, and the current gradually increases until sufficient magnetic force is generated to drive the core to move. In the core movement stage, the core begins to move. As the electromagnetic force required to maintain the core movement decreases, the current begins to decrease. When the core moves to a certain position and touches the operating mechanical load, the speed of the core movement will significantly decrease or stop. In the lock device action stage, the core hits the opening and closing lock device, the core may bounce briefly, and the opening and closing spring begins to act. At this time, the current will rise again. In the continuous action stage, the opening and closing action continues, and the current increases slowly or remains stable. In the current breaking stage, the switch auxiliary contacts are disconnected, and the current quickly decreases to 0.

[0053] The schematic diagram of the current signal change phases of the opening and closing operation is as follows Figure 2 As shown. Figure 2 In the figure, the horizontal axis is the time when the opening and closing operations start, in milliseconds, and the vertical axis is the value of the current signal, in amperes. The current signal goes through five stages: rising, falling, rising again, stabilizing and falling, which correspond to the pre-travel stage, the iron core movement stage, the locking device action stage, the continuous action stage and the current breaking stage respectively. The time period t1 corresponds to the pre-travel stage, and the time period t2 corresponds to the iron core movement stage.

[0054] When circuit breaker fault detection occurs, such as coil circuit undervoltage, coil circuit overvoltage and coil aging, where the current waveform changes are not obvious, the current signal will be different in the pre-stroke stage and the core movement stage compared to the normal working state, and the rising or falling trend of the current signal will be more obvious or weakened.

[0055] Obtain all current peaks in the current sequence, and record the earliest acquisition time corresponding to the current peak as the current transition time of the current sequence. Obtain all current peaks in the standard current sequence, and record the earliest acquisition time corresponding to the current peak as the current transition time of the standard current sequence. The current transition time is the moment when the pre-travel stage changes to the core movement stage during the opening and closing operation.

[0056] At this point, the current transition moments of the current sequence and the standard current sequence are obtained.

[0057] Step S002, obtaining the difference degree of the second stage of opening and closing of the current sequence according to the difference in the change trend of the current signal before the current change moment contained in the current sequence and the standard current sequence, and the difference in the value of the current signal after the current change moment.

[0058] According to the change trend of the current signal contained in the current sequence before the current change moment, the pre-trip phase trend of the current sequence is obtained. According to the value of the current signal contained in the current sequence after the current change moment, the pre-trip phase trend of the current sequence is obtained.

[0059] With the current signal as the vertical axis and the acquisition time corresponding to the current signal as the horizontal axis, a plane rectangular coordinate system is established, and the points corresponding to all current signals whose acquisition time is before the current transformation time contained in the current sequence are marked in the plane rectangular coordinate system, and a straight line is fitted to all points in the plane rectangular coordinate system to obtain the first fitting straight line and the slope of the first fitting straight line, and the slope of the first fitting straight line is recorded as the pre-stroke stage trend of the current sequence. The mean value of all current signals whose acquisition time is after the current transformation time contained in the current sequence is recorded as the core movement stage mean value of the current sequence.

[0060] The pre-travel stage trend of the current sequence is used to indicate the change trend of the current signal of the circuit breaker of the skid-mounted integrated electric control substation during the pre-travel stage. The core movement stage mean of the current sequence is used to indicate the average value of the current signal of the circuit breaker of the skid-mounted integrated electric control substation during the core movement stage.

[0061] According to the same method, based on all current signals collected before the current transition moment contained in the standard current sequence, the pre-stroke stage trend of the standard current sequence and the mean value of the core movement stage of the standard current sequence are obtained. Specifically: with the current signal as the vertical axis and the collection time corresponding to the current signal as the horizontal axis, a plane rectangular coordinate system is established, and the points corresponding to all current signals collected before the current transition moment contained in the standard current sequence are marked in the plane rectangular coordinate system, and all points in the plane rectangular coordinate system are fitted with a straight line to obtain the second fitting straight line and the slope of the second fitting straight line, and the slope of the second fitting straight line is recorded as the pre-stroke stage trend of the standard current sequence. The mean value of all current signals collected after the current transition moment contained in the standard current sequence is recorded as the mean value of the core movement stage of the standard current sequence.

[0062] Preferably, in one embodiment of the present application, the least squares method is used to perform straight line fitting on all points in a plane rectangular coordinate system. Using the least squares method to perform straight line fitting to obtain the fitted straight line and the slope of the fitted straight line is a well-known technique and will not be described in detail.

[0063] According to the difference between the trends of the pre-travel stage of the current sequence and the standard current sequence, and the difference between the mean values ​​of the core movement stage, the difference degree of the second stage of opening and closing of the current sequence is obtained.

[0064] Preferably, as an embodiment of the present application, the absolute value of the difference between the trends of the pre-stroke stage of the current sequence and the standard current sequence is recorded as the first absolute value of the current sequence; the absolute value of the difference between the mean values ​​of the core movement stage of the current sequence and the standard current sequence is recorded as the second absolute value of the current sequence; the linear normalized value of the sum of the first absolute value and the second absolute value of the current sequence is recorded as the difference degree of the second stage of opening and closing of the current sequence.

[0065] Specifically, the calculation formula for the difference degree of the second stage of the opening and closing of the current sequence is:

[0066]

[0067] In the formula, Indicates the difference of the second stage of the opening and closing of the current sequence; Represents the normalization function, which is used to linearly normalize the values ​​in brackets; Indicates the trend of the pre-trip phase of the current sequence; Indicates the trend of the pre-trip phase of the standard current sequence; represents the mean value of the core motion phase of the current sequence; Represents the mean value of the core motion phase of the standard current sequence.

[0068] The difference degree of the second stage of opening and closing of the current sequence is used to indicate the difference between the current signal and the standard current signal in the pre-stroke stage and the core movement stage when the circuit breaker of the skid-mounted integrated electric control substation performs opening and closing operations. It is an evaluation of the possibility of circuit breaker faults with insignificant current waveform changes, such as coil circuit undervoltage, coil circuit overvoltage and coil aging. The greater the difference between the pre-stroke stage trend of the current sequence and the standard current sequence, and the greater the difference between the core movement stage mean, the greater the difference degree of the second stage of opening and closing of the current sequence. At this time, compared with the normal working state, the more obvious the change in the rising or falling trend of the current signal in the pre-stroke stage and the core movement stage is, the greater the possibility of circuit breaker faults with insignificant current waveform changes in the circuit breaker of the skid-mounted integrated electric control substation.

[0069] At this point, the difference degree of the second stage of opening and closing of the current sequence is obtained.

[0070] Step S003, record any current signal contained in the current sequence and the standard current sequence as the target current signal, determine the left local change trend and the right local change trend of the target current signal according to the change trend of adjacent current signals in the local range of the sequence where the target current signal is located, determine the local change trend of the target current signal according to the difference between the left local change trend and the right local change trend of the target current signal, and obtain the abnormality degree of the second stage of opening and closing of the current sequence according to the difference between the local change trends of the current signals contained in the current sequence and the standard current sequence.

[0071] In order to improve the comprehensiveness of circuit breaker fault detection with insignificant current waveform changes, it is also necessary to consider the fault of poor contact of the core in the operating mechanism of the circuit breaker. When the core in the operating mechanism has a poor contact fault when it is pulled in, the current waveform of the circuit breaker of the skid-mounted integrated electric control substation does not change significantly, and only local current signal fluctuations will appear in the current sequence. Therefore, it is necessary to perform local analysis of the current signal in the current sequence to ensure the accuracy and comprehensiveness of circuit breaker fault detection and identification with insignificant current waveform changes.

[0072] The schematic diagram of local current signal fluctuation is as follows Figure 3 As shown. Figure 3 In the figure, the horizontal axis is the start time of the opening and closing operation, in milliseconds, and the vertical axis is the value of the current signal, in amperes. In the time period around 50 milliseconds, there are local current signal fluctuations.

[0073] Any current signal included in the current sequence and the standard current sequence is recorded as a target current signal. This embodiment is described by taking any current signal included in the current sequence and the standard current sequence as an example.

[0074] In the sequence where the target current signal is located, the current signal at the first preset threshold collection time adjacent to the collection time corresponding to the target current signal is recorded as the front adjacent signal of the target current signal, and the current signal at the first preset threshold collection time adjacent to the collection time corresponding to the target current signal is recorded as the rear adjacent signal of the target current signal.

[0075] In this embodiment, the value of the first preset threshold is 3. In actual application, as other implementation methods, the implementer can decide the value of the first preset threshold according to the actual situation, and this application does not impose any special restrictions.

[0076] It can be understood that when the target current signal cannot obtain the first preset threshold number of preceding adjacent signals and following adjacent signals, the target current signal is no longer subjected to the following analysis.

[0077] Taking the previous adjacent signal of the target current signal as the dependent variable and the acquisition time of the previous adjacent signal as the independent variable, the previous adjacent signal of the target current signal is linearly fitted with the acquisition time of the previous adjacent signal to obtain a third fitting straight line and the slope of the third fitting straight line, and the slope of the third fitting straight line is recorded as the left local change trend of the target current signal. Taking the subsequent adjacent signal of the target current signal as the dependent variable and the acquisition time of the subsequent adjacent signal as the independent variable, the subsequent adjacent signal of the target current signal is linearly fitted with the acquisition time of the subsequent adjacent signal to obtain a fourth fitting straight line and the slope of the fourth fitting straight line, and the slope of the fourth fitting straight line is recorded as the right local change trend of the target current signal.

[0078] The local variation trend of the target current signal is determined according to the difference between the left local variation trend and the right local variation trend of the target current signal.

[0079] Preferably, as an embodiment of the present application, the absolute value of the difference between the absolute values ​​of the left local change trend and the right local change trend of the target current signal is recorded as the third absolute value of the target current signal, and the linear normalized value of the third absolute value of the target current signal is recorded as the local change trend of the target current signal.

[0080] Specifically, the calculation formula for the local change trend of the target current signal is:

[0081]

[0082] In the formula, Indicates the local change trend of the target current signal; Represents the normalization function, which is used to linearly normalize the values ​​in brackets; Indicates the left local change trend of the target current signal; Indicates the right local change trend of the target current signal.

[0083] The local change trend of the target current signal is used to evaluate the significance of the change trend change of the current signal within the local range of the target current signal. When the difference between the left local change trend and the right local change trend of the target current signal is greater, the local change trend of the target current signal is greater. At this time, the change in the change trend of the current signal within the local range of the target current signal is more significant.

[0084] The local variation trend of any current signal included in the current sequence and the local variation trend of any current signal included in the standard current sequence can be obtained in the same manner.

[0085] According to the difference between the local variation trend of the current signal contained in the current sequence and the standard current sequence, the abnormality degree of the second stage of opening and closing of the current sequence is obtained.

[0086] Preferably, as an embodiment of the present application, the absolute value of the difference between the local change trends of the current signals at the same position contained in the current sequence and the standard current sequence is recorded as the fourth absolute value of the current signal at the same position, and the linear normalized value of the mean of the fourth absolute values ​​of all current signals at the same position contained in the current sequence and the standard current sequence is recorded as the second stage abnormality of the opening and closing of the current sequence.

[0087] Among them, the current sequence contains The rank of the current signal is .

[0088] Specifically, the calculation formula for the abnormality degree of the second stage of the opening and closing of the current sequence is:

[0089]

[0090] In the formula, Indicates the abnormality degree of the second stage of opening and closing of the current sequence; represents the normalization function; Indicates the minimum value between the number of current signals contained in the current sequence and the number of current signals contained in the standard current sequence; Indicates the Sgn sign function. When the value in the brackets is a positive number, the value of the Sgn sign function is 1. When the value in the brackets is a negative number, the value of the Sgn sign function is -1. When the value in the brackets is 0, the value of the Sgn sign function is 0. Indicates the first The local variation trend of a current signal; Indicates the first The local variation trend of a current signal.

[0091] The second stage abnormality of the opening and closing of the current sequence is a comprehensive evaluation of the significance of the local change trend of all current signals contained in the current sequence. When the difference between the local change trend of the current signal contained in the current sequence and the standard current sequence is greater, the second stage abnormality of the opening and closing of the current sequence is greater. At this time, the change trend of the current signal in the local range of all current signals contained in the current sequence is more significant, and the possibility of circuit breaker faults with unclear current waveform changes, such as poor contact of the core suction in the operating mechanism, is greater during the opening and closing operation.

[0092] At this point, the abnormality degree of the second stage of opening and closing of the current sequence is obtained.

[0093] Step S004, obtaining the fault detection result of the skid-mounted electric control integrated substation according to the difference degree of the second stage of opening and closing of the current sequence and the abnormality degree of the second stage of opening and closing.

[0094] The fault possibility of the current sequence is obtained according to the difference degree of the second stage of opening and closing of the current sequence and the abnormality degree of the second stage of opening and closing.

[0095] Preferably, as an embodiment of the present application, the product of the difference degree of the second stage of opening and closing of the current sequence and the abnormality degree of the second stage of opening and closing is recorded as the fault possibility of the current sequence.

[0096] A second preset threshold is set. When the fault probability of the current sequence is greater than or equal to the second preset threshold, it is determined that a circuit breaker fault occurs during the opening and closing operation of the circuit breaker of the skid-mounted integrated electric control substation. When the fault probability of the current sequence is less than the second preset threshold, it is determined that no circuit breaker fault occurs during the opening and closing operation of the circuit breaker of the skid-mounted integrated electric control substation.

[0097] In this embodiment, the value of the second preset threshold is 0.7.

[0098] It should be noted that in the skid-mounted integrated electric control substation, in addition to playing a control and protection role in the gas-insulated switchgear and air-insulated switchgear, the circuit breaker can also play a corresponding role in various detection and control types of equipment, including but not limited to air conditioning control, temperature and humidity monitoring, lighting control, dehumidifier control, UPS monitoring, emergency lighting control, and electric heater control.

[0099] When each monitoring and control system is running in the skid-mounted integrated electric control substation, the above process is used to perform fault detection on the circuit breaker in each monitoring and control system, and intelligent monitoring of each monitoring and control system in the skid-mounted integrated electric control substation is achieved through the fault detection of the circuit breaker.

[0100] At this point, the fault detection results of the skid-mounted electric-control integrated substation are obtained.

[0101] Based on the same inventive concept as the above method, an embodiment of the present invention also provides an intelligent monitoring system for a skid-mounted electrically-controlled integrated substation, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein when the processor executes the computer program, the steps of any one of the above-mentioned intelligent monitoring methods for a skid-mounted electrically-controlled integrated substation are implemented.

[0102] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An intelligent monitoring method for a skid-mounted electric control integrated substation, characterized in that: The method comprises the following steps: During the opening and closing operation of the circuit breaker of the skid-mounted integrated electric control substation, current signals are collected, and a current sequence is obtained according to the current signals; during the opening and closing operation of the circuit breaker in normal operation, current signals of normal operation are collected, and a standard current sequence is obtained according to the current signals of normal operation; and according to the values ​​of the current signals, current transition moments in the collection moments corresponding to the current signals contained in the current sequence and the standard current sequence are respectively determined; According to the difference in the change trend of the current signal before the current change moment at the acquisition moment contained in the current sequence and the standard current sequence, and the difference in the value of the current signal after the current change moment, the difference degree of the second stage of opening and closing of the current sequence is obtained; Record any current signal included in the current sequence and the standard current sequence as the target current signal, determine the left local change trend and the right local change trend of the target current signal according to the change trend of the adjacent current signals in the local range of the sequence where the target current signal is located, determine the local change trend of the target current signal according to the difference between the left local change trend and the right local change trend of the target current signal, and obtain the second stage abnormality of the opening and closing of the current sequence according to the difference between the local change trends of the current signals included in the current sequence and the standard current sequence; Obtain the fault detection results of the skid-mounted integrated electric control substation based on the difference degree of the second stage of opening and closing of the current sequence and the abnormality degree of the second stage of opening and closing; The specific method of obtaining the difference degree of the second stage of opening and closing of the current sequence according to the difference in the change trend of the current signal at the acquisition time before the current change time contained in the current sequence and the standard current sequence, and the difference in the value of the current signal after the current change time, includes: With the current signal as the vertical axis and the collection time corresponding to the current signal as the horizontal axis, a plane rectangular coordinate system is established, and the points corresponding to all current signals whose collection time is before the current transformation time contained in the current sequence are marked, and straight line fitting is performed on all points to obtain a first fitting straight line, and the slope of the first fitting straight line is recorded as the pre-stroke stage trend of the current sequence, and the mean value of all current signals whose collection time is after the current transformation time contained in the current sequence is recorded as the core movement stage mean value of the current sequence; Mark points corresponding to all current signals contained in the standard current sequence at the time of collection before the current transition moment in the plane rectangular coordinate system, perform straight line fitting on all points in the plane rectangular coordinate system to obtain a second fitting straight line, record the slope of the second fitting straight line as the pre-stroke stage trend of the standard current sequence, and record the mean value of all current signals contained in the standard current sequence at the time of collection after the current transition moment as the core movement stage mean value of the standard current sequence; According to the difference between the trends of the pre-travel stage of the current sequence and the standard current sequence, and the difference between the mean values ​​of the core movement stage, the difference degree of the second stage of the opening and closing of the current sequence is obtained; The method of obtaining the difference degree of the second stage of opening and closing of the current sequence according to the difference between the trends of the pre-travel stage of the current sequence and the standard current sequence, and the difference between the mean values ​​of the core movement stage, includes the following specific methods: The absolute value of the difference between the trend of the pre-travel stage of the current sequence and the standard current sequence is recorded as the first absolute value of the current sequence; the absolute value of the difference between the mean value of the core movement stage of the current sequence and the standard current sequence is recorded as the second absolute value of the current sequence; The linear normalized value of the sum of the first absolute value and the second absolute value of the current sequence is recorded as the second stage difference of the opening and closing of the current sequence; The method of determining the left local change trend and the right local change trend of the target current signal according to the change trend of the adjacent current signals within the local range of the sequence where the target current signal is located includes the following specific methods: In the sequence where the target current signal is located, the current signal at the first preset threshold number of acquisition moments before the acquisition moment corresponding to the target current signal is recorded as the previous adjacent signal of the target current signal, and the current signal at the first preset threshold number of acquisition moments after the acquisition moment corresponding to the target current signal is recorded as the subsequent adjacent signal of the target current signal; Determine a left local change trend and a right local change trend of the target current signal according to a front adjacent signal and a rear adjacent signal of the target current signal; The specific method of determining the left local change trend and the right local change trend of the target current signal according to the front adjacent signal and the rear adjacent signal of the target current signal includes: Perform straight line fitting on the previous adjacent signal of the target current signal and the acquisition time of the previous adjacent signal to obtain a third fitting straight line, and record the slope of the third fitting straight line as the left local change trend of the target current signal; Perform straight-line fitting on the subsequent adjacent signal of the target current signal and the acquisition time of the subsequent adjacent signal to obtain a fourth fitting straight line, and record the slope of the fourth fitting straight line as the right local variation trend of the target current signal; The specific method of obtaining the abnormality degree of the second stage of the opening and closing of the current sequence includes: The absolute value of the difference between the local change trends of the current signals of the same order contained in the current sequence and the standard current sequence is recorded as the fourth absolute value of the current signal of the same order, and the linear normalized value of the average of the fourth absolute values ​​of all the current signals of the same order contained in the current sequence and the standard current sequence is recorded as the abnormality degree of the second stage of opening and closing of the current sequence; The method of obtaining the fault detection result of the skid-mounted integrated electric control substation according to the difference degree of the second stage of the opening and closing of the current sequence and the abnormality degree of the second stage of the opening and closing includes: The product of the difference degree of the second stage of opening and closing of the current sequence and the abnormality degree of the second stage of opening and closing is recorded as the fault possibility of the current sequence; When the fault probability of the current sequence is greater than or equal to a second preset threshold, it is determined that a circuit breaker fault occurs during the opening and closing operation of the circuit breaker of the skid-mounted electric-controlled integrated substation; When the fault probability of the current sequence is less than the second preset threshold, it is determined that no circuit breaker fault occurs during the opening and closing operation of the circuit breaker of the skid-mounted electronically controlled integrated substation.

2. The intelligent monitoring method for a skid-mounted electric-control integrated substation according to claim 1, characterized in that: The specific method of determining the current transition moments in the acquisition moments corresponding to the current signals contained in the current sequence and the standard current sequence respectively according to the values ​​of the current signals includes: Obtain all current peaks in the current sequence, and record the earliest acquisition time corresponding to the current peak as the current transition time of the current sequence; All current peaks in the standard current sequence are obtained, and the earliest acquisition time corresponding to the current peak is recorded as the current transition time of the standard current sequence.

3. The intelligent monitoring method for a skid-mounted electric-control integrated substation according to claim 1, characterized in that: The specific method of determining the local change trend of the target current signal includes: The absolute value of the difference between the absolute values ​​of the left local change trend and the right local change trend of the target current signal is recorded as the third absolute value of the target current signal, and the linear normalized value of the third absolute value of the target current signal is recorded as the local change trend of the target current signal.

4. An intelligent monitoring system for a skid-mounted electric-control integrated substation, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 3 are implemented.

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