A power grid fault authenticity discrimination system and method based on protection action event timing

Abstract

The application discloses a power grid fault authenticity discrimination system and method based on protection action event timing, collects operation information of each protection device to provide a comprehensive view, can be used for further analyzing a fault, and helps to preliminarily judge whether the fault is a real fault; correlation value calculation provides a quantitative method, similarity of fault data of different protection actions is compared, and whether the protection actions are reactions to the same fault can be judged, which helps to identify logical correlation between the protection actions and assess whether the protection actions are reactions to the same fault position; a preset correlation value threshold is used to assess correlation between other protection actions and a triggered protection action, and whether the fault is a real fault or a suspected fault is judged.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power grid fault diagnosis, and in particular to a power grid fault authenticity discrimination system and method based on protection action event timing. BACKGROUND

[0002] The fault information and the recording file are relatively complete and timely, which lays a foundation for comprehensive analysis of the power grid fault. However, the test action event information at the current protection inspection will interfere with accurate judgment of the power grid fault, and affect the accuracy and correctness of the power grid fault data processing and comprehensive analysis. In order to realize practical application of the power grid fault analysis, a power grid fault authenticity discrimination method based on protection action event timing needs to be researched by using scientific and technological means to solve the problem, improve the correctness and usability of the power grid fault analysis, provide accurate power grid analysis information for dispatching and operation, shorten the fault analysis time, improve the power grid fault analysis capability, improve the power grid fault recovery capability, and ensure stable operation of the power grid fault.

[0003] A distributed power supply coordinated control method is disclosed in Chinese Patent No. CN111835786B. By comparing the stability evaluation index calculated by the actual output power of each region with the preset index value stored in advance, it is judged whether the distributed power supply in each region of the distribution network produces unstable power. This evaluation method is suitable for simple structure of the distributed power supply active distribution network, but for complex power transmission lines, since the evaluation result is only whether it is stable, further screening of the reason for unstable power cannot be performed.

[0004] In summary, in the field of comprehensive diagnosis of power grid faults, the following problems exist: (1) the test action event information at the current protection inspection will interfere with accurate judgment of the power grid fault, and affect the accuracy and correctness of the power grid fault data processing and comprehensive analysis; (2) the current evaluation method for the power grid is single, by comparing the stability evaluation index calculated by the actual output current of each region with the preset index value stored in advance, it is judged whether the current of the distributed power supply in each region of the distribution network is stable, and the evaluation result is only whether it is stable, and further screening of the reason for unstable current cannot be performed. SUMMARY

[0005] The present application provides a power grid fault authenticity discrimination system and method based on protection action event timing, which can improve the judgment effect of fault authenticity.

[0006] Technical solution: The power grid fault authenticity discrimination system based on protection action event timing, comprising: a query module and a protection action management module; the query module: used for monitoring the protection device, when the protection device starts the protection action, the protection action is recorded as a triggered protection action, and the protection action information of the triggered protection action is recorded, the protection action information of the triggered protection action includes: a fault interval, a voltage level of the fault interval, a protection action time, and a required query interval and a time window are generated according to the protection action information, and the protection action information of the triggered protection action, the required query interval and the time window are transmitted to the protection action management module; the protection action management module: used for querying the total signal in the time window according to the protection action information of the triggered protection action, the required query interval and the time window transmitted by the query module, if the total signal exists, a real fault signal is generated and transmitted to the WEB terminal diagnosis display interface, and the WEB terminal diagnosis display interface displays the information: "the current triggered protection action is caused by a real fault", otherwise, the protection action of the required query interval is queried, a protection action set is obtained, the protection action set is filtered, the protection action of the protection action set which is a test protection action in the time window is removed, a filtered protection action set is obtained, and the filtered protection action set is discriminated to generate a discrimination fault signal which is transmitted to the WEB terminal diagnosis display interface, and the WEB terminal diagnosis display interface displays accordingly.

[0007] Further, when the voltage level of the fault interval is 220kV and above, the required query interval is the fault interval, other intervals of the fault interval and related intervals of the fault interval, the start time of the time window is the action time of the triggered protection action, and the end time of the time window is the action time of the triggered protection action plus 10 seconds backward;

[0008] When the voltage level of the fault interval is 110kV, the required query interval is the other interval of the fault interval, the start time of the time window is the action time of the triggered protection action, and the end time of the time window is the action time of the triggered protection action plus 10 seconds backward;

[0009] When the voltage level of the fault interval is 35kV and below, the required query interval is the fault interval, the start time of the time window is the action time of the triggered protection action, and the end time of the time window is the action time of the triggered protection action plus 160 seconds backward.

[0010] Further, the other interval of the fault interval is an interval other than the fault interval under the same plant station, and the related interval of the fault interval is an interval where the A set protection and the B set protection of one plant station start the protection action, and the interval where the A set protection and the B set protection of the other plant station are located.

[0011] Further, the query module comprises: an interval storage unit, a query unit, and a time window generation unit; wherein,

[0012] The interval storage unit is configured to store the fault interval, the related interval of the fault interval, and the other interval of the fault interval.

[0013] The query unit is configured to search the interval storage unit with the fault interval triggering the protection action as an index, search the related interval of the fault interval and the other interval of the fault interval when the voltage level of the fault interval is 220 kV or above, and transmit the fault interval, the related interval of the fault interval, and the other interval of the fault interval to the protection action management module; search the other interval of the fault interval and transmit the other interval of the fault interval to the protection action management module when the voltage level of the fault interval is 110 kV; and transmit the fault interval to the protection action management module when the voltage level of the fault interval is 35 kV or below.

[0014] The time window generation unit is configured to generate a time window according to the action time triggering the protection action, and the time window generation rule is that the start time of the time window is the action time triggering the protection action, and the end time of the time window is the action time triggering the protection action plus 10 seconds backward when the voltage level of the fault interval is 220 kV or above or the voltage level of the fault interval is 110 kV; and the start time of the time window is the action time triggering the protection action, and the end time of the time window is the action time triggering the protection action plus 160 seconds backward when the voltage level of the fault interval is 35 kV or below.

[0015] After the time window generation unit generates the time window, the time window generation unit transmits the time window to the protection action management module.

[0016] Further, the protection action management module comprises: a protection action storage unit, a filtering unit, and a signal generation unit; wherein,

[0017] The protection action storage unit is configured to store the protection action and the total accident signal.

[0018] The signal generation unit is configured to query the total accident signal in the time window according to the time window transmitted by the time window generation unit, generate a real fault signal and transmit the real fault signal to a WEB terminal diagnosis display interface if the total accident signal exists, and display information "the current triggering protection action is caused by a real fault" on the WEB terminal diagnosis display interface; otherwise, the signal generation unit is configured to query the protection action of the interval to be queried in the time window according to the interval to be queried transmitted by the query unit and the time window transmitted by the time window generation unit, obtain a protection action set, and transmit the protection action set to the filtering unit.

[0019] Filtering unit: used for filtering the protection action set transmitted by the protection action storage unit, obtaining a filtered protection action set, and the filtering rule is: eliminating the protection action in the protection action set which is a trial protection action within the time window; and transmitting the filtered protection action set to the discrimination unit;

[0020] Discrimination unit: used for discriminating according to the filtered protection action set: when the voltage level of the fault interval is 220 kV and above, when there are two situations as follows, the discrimination unit generates a real fault signal and transmits it to the WEB terminal diagnosis display interface, otherwise the discrimination unit generates a suspected fault signal and transmits it to the WEB terminal diagnosis display interface: situation one: there are protection actions of other intervals and protection actions of the same interval in the filtered protection action set; situation two: there are protection actions of other intervals and protection actions of related intervals in the filtered protection action set;

[0021] For when the voltage level of the fault interval is 110 kV, the discrimination unit judges whether it is a real fault according to the other interval discrimination strategy, if it is a real fault, the discrimination unit generates a real fault signal and transmits it to the WEB terminal diagnosis display interface, otherwise the discrimination unit generates a suspected fault signal and transmits it to the WEB terminal diagnosis display interface;

[0022] For when the voltage level of the fault interval is 35 kV and below, the discrimination unit judges whether it is a real fault according to the fault interval expansion discrimination strategy, if it is a real fault, the discrimination unit generates a real fault signal and transmits it to the WEB terminal diagnosis display interface, otherwise the discrimination unit generates a suspected fault signal and transmits it to the WEB terminal diagnosis display interface.

[0023] Correspondingly, a power grid fault authenticity discrimination method based on protection action event timing, comprising the following steps:

[0024] Step 1, the query module monitors the protection device, when the protection device starts the protection action, records the protection action as a triggered protection action, and records the protection action information of the triggered protection action, the protection action information of the triggered protection action includes: fault interval, voltage level of fault interval, protection action time, and generates the interval to be queried and the time window according to the protection action information, and transmits the protection action information of the triggered protection action, the interval to be queried and the time window to the protection action management module;

[0025] Step 2, the protection action management module generates the time window transmitted by the time window generating unit, queries the total accident signal in the time window, and if the total accident signal exists, generates a real fault signal and transmits it to the WEB terminal diagnosis display interface. The WEB terminal diagnosis display interface displays the information: "the current triggered protection action is caused by a real fault"; otherwise, the protection action management module generates the time window transmitted by the time window generating unit according to the interval to be queried transmitted by the query module, queries the protection action of the interval to be queried in the time window, and obtains a protection action set;

[0026] Step 3, the protection action management module filters the protection action set, removes the protection action in the protection action set which is a test protection action in the time window, and obtains a filtered protection action set;

[0027] Step 4, the protection action management module discriminates according to the filtered protection action set, generates a discrimination fault signal, and transmits it to the WEB terminal diagnosis display interface.

[0028] Further, in step 1, the query module monitors the protection device, generates the required content to the protection action management module according to the protection action information

[0029] Step 11, the query module monitors the protection device, when the protection device starts the protection action, records the protection action as a triggered protection action, and records the protection action information of the triggered protection action. The protection action information of the triggered protection action includes: fault interval, voltage level of the fault interval, protection action time;

[0030] Step 12, the query module judges the voltage level of the fault interval of the triggered protection action; when the voltage level of the fault interval of the triggered protection action is 220kV and above, step 13 is executed; when the voltage level of the fault interval of the triggered protection action is 110kV, step 14 is executed; when the voltage level of the fault interval of the triggered protection action is 35kV and below, step 15 is executed;

[0031] Step 13, the query module generates the interval to be queried and the time window. The interval to be queried is the fault interval, other intervals of the fault interval, and related intervals of the fault interval. The start time of the time window is the action time of the triggered protection action, and the end time of the time window is the action time of the triggered protection action plus 10 seconds. The query module transmits the interval to be queried and the time window to the protection action management module, and executes step 16;

[0032] Step 14, the query module generates the interval to be queried and the time window, the interval to be queried is the other interval of the fault interval, the start time of the time window is the action time of triggering the protection action, and the end time of the time window is the action time of triggering the protection action plus 10 seconds backward; the query module transmits the interval to be queried and the time window to the protection action management module, and step 16 is performed;

[0033] Step 15, the query module generates the interval to be queried and the time window, the interval to be queried is the fault interval, the start time of the time window is the action time of triggering the protection action, and the end time of the time window is the action time of triggering the protection action plus 160 seconds backward; the query module transmits the interval to be queried and the time window to the protection action management module, and step 16 is performed;

[0034] Step 16, end of step 1.

[0035] Further, in step 4, the protection action management module discriminates according to the filtered protection action set to generate a discrimination fault signal transmitted to the WEB terminal diagnosis display interface, which specifically includes the following steps:

[0036] Step 41, judge the voltage level of the fault interval of the protection action, when the voltage level of the fault interval is 220kV and above, step 42 is executed; when the voltage level of the fault interval is 110kV, step 43 is executed; when the voltage level of the fault interval is 35kV and below, step 44 is executed;

[0037] Step 42, when there are two situations as follows, the discrimination unit generates a real fault signal and transmits it to the WEB terminal diagnosis display interface, and the WEB terminal diagnosis display interface displays the information: "the current triggered protection action is caused by real fault", otherwise the discrimination unit generates a suspected fault signal and transmits it to the WEB terminal diagnosis display interface, and the WEB terminal diagnosis display interface displays the information: "the current triggered protection action is caused by suspected fault", situation one: there are other interval protection actions and same interval protection actions in the filtered protection action set; situation two: there are other interval protection actions and related interval protection actions in the filtered protection action set, step 45 is executed;

[0038] Step 43, the discrimination unit judges whether it is a real fault according to the other interval discrimination strategy, if it is a real fault, the discrimination unit generates a real fault signal and transmits it to the WEB terminal diagnosis display interface, and the WEB terminal diagnosis display interface displays the information: "the current triggered protection action is caused by real fault", otherwise the discrimination unit generates a suspected fault signal and transmits it to the WEB terminal diagnosis display interface, and the WEB terminal diagnosis display interface displays the information: "the current triggered protection action is caused by suspected fault", step 45 is executed;

[0039] Step 44, the discrimination unit determines whether it is a real fault according to the fault interval expansion discrimination strategy. If it is a real fault, the discrimination unit generates a real fault signal and transmits it to the WEB terminal diagnosis display interface. The WEB terminal diagnosis display interface displays the information: "the current triggering protection action is caused by a real fault". Otherwise, the discrimination unit generates a suspected fault signal and transmits it to the WEB terminal diagnosis display interface. The WEB terminal diagnosis display interface displays the information: "the current triggering protection action is caused by a suspected fault". Step 45 is executed.

[0040] Step 45, end discrimination.

[0041] Further, in step 43, the other interval discrimination strategy is specifically: calculating the real fault metric value of the protection action set, and the calculation method is as follows:

[0042]

[0043] Wherein, C TRUE represents the real fault metric value of the protection action set; P(D→H TURE ) represents the occurrence rate of real fault judged by the protection action set; P(D→H SUSP ) represents the occurrence rate of suspected fault judged by the protection action set; H TURE represents a real fault event, H SUSP represents a suspected fault event, P(H TURE ) represents the occurrence rate of protection action caused by real fault in the case of 110kV voltage level of fault interval; P(H SUSP ) represents the occurrence rate of protection action caused by suspected fault in the case of 110kV voltage level of fault interval; D i represents the i-th subset of the protection action set D; D represents the protection action set; P(D i ) represents the occurrence rate of protection action set D i in the case of protection event; P(D i |H TURE ) represents the occurrence rate of protection action set D i in the case of real fault event; P(D i |H SUSP ) represents the occurrence rate of protection action set D i in the case of suspected fault event; whether the real fault metric value of the protection action set is greater than 1 is determined. If it is greater than 1, it is determined to be a real fault; otherwise, it is determined to be a suspected fault.

[0044] Further, in step 44, the fault interval expansion discrimination strategy is specifically: querying the fault device information of the protection action of the protection action set, the fault device information of other protection actions includes: distance measurement, fault phase, fault voltage, fault current, zero sequence current; calculating the correlation value of other protection actions of the protection action set and the triggered protection action, wherein the other protection actions are the protection actions in the protection action set excluding the triggered protection action, and the calculation method is as follows:

[0045]

[0046] wherein G SUM represents the correlation value of the other protection action and the triggered protection action, j represents the number of the other protection action, U represents the set of the number of the other protection action, A j represents the fault device information of the jth other protection action, A0 represents the fault device information of the triggered protection action, and N represents the number of the other protection actions in the protection action set; it is judged whether the correlation value of the other protection action and the triggered protection action is greater than the correlation value threshold value, if it is greater than the correlation value threshold value, it is determined to be a real fault; otherwise, it is determined to be a suspected fault; the correlation value threshold value is 0.8.

[0047] Beneficial effects: compared with the prior art, the present application has the following remarkable advantages: (1) by inquiring other protection actions in the corresponding time window, and combining other protection actions with the triggered protection action, the authenticity of the power grid fault is determined, compared with the authenticity determination for a single protection action, multiple protection action determination can overcome the influence of accidental disturbance on authenticity determination, increase the determination dimension of authenticity, thereby improving the determination effect of fault authenticity; (2) the filtering method is adopted to filter out the protection action of the test protection action in the time window, so that the judgment of fault authenticity excludes the interference of the test protection action, thereby making the judgment of fault authenticity more accurate; (3) according to the voltage level of the fault interval, the corresponding discrimination method is used: when the voltage level of the fault interval of the triggered protection action is 220kV and above, there are A / B double protection and line two sides same protection, the possibility of real fault is analyzed through the action of four sets of protection, which is more in line with the operation mechanism of the protection device with voltage level of 220kV and above; when the voltage level of the fault interval is 110kV, since there is only a single protection, the maintenance and fault are distinguished by the disturbance data characteristics of other intervals; through the effectiveness reasoning, the effectiveness reasoning process is based on the connection between protection actions, thereby increasing the real basis of fault authenticity determination; when the voltage level of the fault interval is 35kV and below, since the power grid protection action behavior is relatively complex, the differential coordination is relatively loose, and the signal capture of non-fault interval is difficult, therefore it is necessary to supplement the extended analysis time window, to strengthen the capture ability of disturbance data, and to improve the discrimination accuracy, by using the corresponding discrimination method according to the voltage level of the fault interval, the discrimination accuracy can be effectively improved. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 The system structure diagram of the present application.

[0049] Figure 2 The method flowchart of the present application. DETAILED DESCRIPTION

[0050] As Figure 1As shown, a power grid fault authenticity discrimination system based on protection action event timing comprises: an electrical connection with a protection device, when the protection device starts a protection action, the power grid fault authenticity discrimination system based on protection action event timing is triggered to determine whether the protection action is caused by a real power grid fault, the power grid fault authenticity discrimination system based on protection action event timing comprises: a query module, a protection action management module; wherein the query module: for monitoring the protection device, when the protection device starts the protection action, the protection action is recorded as a triggered protection action, and the protection action information of the triggered protection action is recorded, the protection action information of the triggered protection action includes: fault interval, voltage level of fault interval, protection action time, and generates the interval and time window that need to be queried according to the protection action information, and transmits the protection action information of the triggered protection action, the time window to the protection action management module;

[0051] When the voltage level of the fault interval is 220kV and above, the interval to be queried is the fault interval, other intervals of the fault interval, and related intervals of the fault interval, the start time of the time window is the action time of the triggered protection action, and the end time of the time window is the action time of the triggered protection action plus 10 seconds backward;

[0052] When the voltage level of the fault interval is 110kV, the interval to be queried is the other interval of the fault interval, the start time of the time window is the action time of the triggered protection action, and the end time of the time window is the action time of the triggered protection action plus 10 seconds backward;

[0053] When the voltage level of the fault interval is 35kV and below, the interval to be queried is the fault interval, the start time of the time window is the action time of the triggered protection action, and the end time of the time window is the action time of the triggered protection action plus 160 seconds backward;

[0054] The protection action management module: for querying the total signal in the time window according to the protection action information of the triggered protection action, the interval to be queried, and the time window transmitted by the query module, if there is an accident total signal, a real fault signal is generated and transmitted to the WEB end diagnosis display interface, and the WEB end diagnosis display interface displays the information: "the current triggered protection action is caused by a real fault"; otherwise, the protection action of the interval to be queried in the time window is queried, the protection action set is obtained, the protection action set is filtered to remove the protection action in the protection action set which is a test protection action in the time window, the filtered protection action set is obtained, and the filtered protection action set is discriminated to generate a discrimination fault signal and transmit it to the WEB end diagnosis display interface.

[0055] It is worth mentioning that the other interval of the fault interval is the interval in which the power grid fault occurs except for the interval of the same substation, and the related interval is the interval in which the A set protection and the B set protection of one substation are started to act as protection when the A set protection and the B set protection of the other substation are started to act as protection. In the field of relay protection, the A set protection and the B set protection of one substation are two independent protections.

[0056] In the field of relay protection, the fault interval refers to the location attribute of the fault occurrence, which is the line section of the protection device in the power system, and is also called the protection interval or the protection range. Any fault in this interval should be detected and isolated by the protection device in the interval.

[0057] Each protection interval usually has its own relay protection device, which is set to cover a specific line or device. When a fault occurs in the system, the corresponding relay protection device will act to isolate the fault interval and limit the impact of the fault on the power system. The fault interval is an attribute of the protection action.

[0058] The query module comprises an interval storage unit, a query unit, and a time window generation unit.

[0059] The interval storage unit is configured to store the fault interval, the related interval of the fault interval, and the other interval of the fault interval.

[0060] The query unit is configured to search the interval storage unit with the fault interval triggering the protection action as an index, search the related interval of the fault interval and the other interval of the fault interval when the voltage level of the fault interval is 220 kV or above, search the other interval of the fault interval when the voltage level of the fault interval is 110 kV, and transmit the fault interval, the related interval of the fault interval, and the other interval of the fault interval to the protection action management module. When the voltage level of the fault interval is 35 kV or below, the fault interval is transmitted to the protection action management module. The query unit transmits the protection action information triggering the protection action to the discrimination unit of the protection action management module.

[0061] The time window generation unit is configured to generate a time window according to the action time triggering the protection action. The time window generation rule is that when the voltage level of the fault interval is 220 kV or above or the voltage level of the fault interval is 110 kV, the start time of the time window is the action time triggering the protection action, and the end time of the time window is the action time triggering the protection action plus 10 seconds backward. When the voltage level of the fault interval is 35 kV or below, the start time of the time window is the action time triggering the protection action, and the end time of the time window is the action time triggering the protection action plus 160 seconds backward.

[0062] After the time window generating unit generates the time window, the time window generating unit transmits the time window to the protection action management module.

[0063] The protection action management module comprises a protection action storage unit, a filtering unit, and a signal generating unit.

[0064] The protection action storage unit is configured to store protection actions and an accident total signal. The protection action storage unit stores the protection actions and the accident total signal in sequence according to the time sequence of the protection actions and the accident total signal and in combination with the received time. The accident total signal is an accident total signal of a monitoring system. The monitoring system is a system configured to monitor the operating state of a power grid. When the monitoring system detects a power grid fault, the monitoring system starts a corresponding program, including sending the accident total signal. The power grid faults that can be detected by the monitoring system are relatively obvious, and the types of the faults that can be detected are limited. The power grid faults that can be monitored by the monitoring system are faults related to the safety and stability of the power grid.

[0065] The protection actions stored by the protection action storage unit include test protection actions. The test protection actions are test actions performed by a worker on a protection device during protection maintenance.

[0066] The protection actions stored by the protection action storage unit include time stamps of the protection actions.

[0067] The accident total signal stored by the protection action storage unit includes a time stamp of the accident total signal.

[0068] The protection action storage unit is configured to query the accident total signal in the time window according to the time window transmitted by the time window generating unit. If the accident total signal exists, a real fault signal is generated and transmitted to a WEB terminal diagnosis display interface. The WEB terminal diagnosis display interface displays the information: “the current triggered protection action is caused by a real fault”. Otherwise, the protection action set is obtained by querying the protection actions in the interval to be queried in the time window according to the interval to be queried transmitted by the query unit and the time window transmitted by the time window generating unit, and the protection action set is transmitted to the filtering unit.

[0069] The filtering unit is configured to filter the protection action set transmitted by the protection action storage unit to obtain a filtered protection action set. The filtering rule is to remove the protection actions in the protection action set that are test protection actions in the time window. The filtered protection action set is transmitted to the discrimination unit.

[0070] The discrimination unit is used for discriminating according to the filtered protection action set: when the voltage level of the fault interval is 220 kV and above, when there are two situations as follows, the discrimination unit generates a true fault signal and transmits to the WEB terminal diagnosis display interface, otherwise the discrimination unit generates a suspected fault signal and transmits to the WEB terminal diagnosis display interface: situation one: there are protection actions of other intervals and protection actions of the same interval in the filtered protection action set; situation two: there are protection actions of other intervals and protection actions of related intervals in the filtered protection action set;

[0071] For when the voltage level of the fault interval is 110 kV, the discrimination unit judges whether it is a true fault according to the other interval discrimination strategy, if it is a true fault, the discrimination unit generates a true fault signal and transmits to the WEB terminal diagnosis display interface, otherwise the discrimination unit generates a suspected fault signal and transmits to the WEB terminal diagnosis display interface;

[0072] For when the voltage level of the fault interval is 35 kV and below, the discrimination unit judges whether it is a true fault according to the fault interval expansion discrimination strategy, if it is a true fault, the discrimination unit generates a true fault signal and transmits to the WEB terminal diagnosis display interface, otherwise the discrimination unit generates a suspected fault signal and transmits to the WEB terminal diagnosis display interface.

[0073] As shown in Figure 2 A power grid fault authenticity discrimination method based on protection action event timing, which is realized based on a power grid fault authenticity discrimination system based on protection action event timing, is used for discriminating whether the protection action is caused by a true power grid fault, and includes the following specific steps:

[0074] S1: The query module monitors the protection device, when the protection device starts the protection action, records the protection action as a triggered protection action, and records the protection action information of the triggered protection action, the protection action information of the triggered protection action includes: fault interval, voltage level of fault interval, protection action time, and generates the interval and time window that need to be queried according to the protection action information, and transmits the protection action information of the triggered protection action, the interval and time window that need to be queried to the protection action management module, S1 includes the following steps:

[0075] S101: The query module monitors the protection device, when the protection device starts the protection action, records the protection action as a triggered protection action, and records the protection action information of the triggered protection action, the protection action information of the triggered protection action includes: fault interval, voltage level of fault interval, protection action time;

[0076] S102: The query module judges the voltage level of the fault interval triggering the protection action; when the voltage level of the fault interval triggering the protection action is 220 kV and above, S103 is executed; when the voltage level of the fault interval triggering the protection action is 110 kV, S104 is executed; when the voltage level of the fault interval triggering the protection action is 35 kV and below, S105 is executed;

[0077] S103: The query module generates the interval and time window to be queried, the interval to be queried being the fault interval, other interval of the fault interval, and related interval of the fault interval, the start time of the time window being the action time of triggering the protection action, and the end time of the time window being the action time of triggering the protection action plus 10 seconds backward; the query module transmits the interval and time window to be queried to the protection action management module, and S106 is executed;

[0078] S104: The query module generates the interval and time window to be queried, the interval to be queried being the other interval of the fault interval, the start time of the time window being the action time of triggering the protection action, and the end time of the time window being the action time of triggering the protection action plus 10 seconds backward; the query module transmits the interval and time window to be queried to the protection action management module, and S106 is executed;

[0079] S105: The query module generates the interval and time window to be queried, the interval to be queried being the fault interval, the start time of the time window being the action time of triggering the protection action, and the end time of the time window being the action time of triggering the protection action plus 160 seconds backward; the query module transmits the interval and time window to be queried to the protection action management module, and S106 is executed;

[0080] S106: S1 is ended.

[0081] S2: The protection action management module queries the accident total signal in the time window according to the time window transmitted by the query module, generates a real fault signal and transmits it to the WEB terminal diagnosis display interface if there is an accident total signal, and the WEB terminal diagnosis display interface displays the information: "the current triggering protection action is caused by a real fault"; otherwise, the protection action management module queries the protection action of the interval to be queried in the time window according to the interval and time window to be queried transmitted by the query module, and obtains a protection action set;

[0082] S3: The protection action management module filters the protection action set, and removes the protection action in the protection action set that is a test protection action in the time window, to obtain a filtered protection action set.

[0083] S4: The protection action management module discriminates according to the filtered protection action set, generates a discrimination fault signal and transmits to the WEB terminal diagnosis display interface, and S4 specifically includes the following steps:

[0084] S401: Determine the voltage level of the fault interval of the protection action, when the voltage level of the fault interval is 220kV and above, execute S402; when the voltage level of the fault interval is 110kV, execute S403; when the voltage level of the fault interval is 35kV and below, execute S404;

[0085] S402: When there are two situations as follows, the discrimination unit generates a real fault signal and transmits to the WEB terminal diagnosis display interface, and the WEB terminal diagnosis display interface displays the information: "The current triggered protection action is caused by real fault", otherwise the discrimination unit generates a suspected fault signal and transmits to the WEB terminal diagnosis display interface, and the WEB terminal diagnosis display interface displays the information: "The current triggered protection action is caused by suspected fault", execute S405; Situation one: there are other interval protection actions and same interval protection actions in the filtered protection action set; Situation two: there are other interval protection actions and related interval protection actions in the filtered protection action set;

[0086] S403: The discrimination unit determines whether it is a real fault according to the other interval discrimination strategy, if it is a real fault, the discrimination unit generates a real fault signal and transmits to the WEB terminal diagnosis display interface, and the WEB terminal diagnosis display interface displays the information: "The current triggered protection action is caused by real fault", otherwise the discrimination unit generates a suspected fault signal and transmits to the WEB terminal diagnosis display interface, and the WEB terminal diagnosis display interface displays the information: "The current triggered protection action is caused by suspected fault", execute S405;

[0087] S404: The discrimination unit determines whether it is a real fault according to the fault interval expansion discrimination strategy, if it is a real fault, the discrimination unit generates a real fault signal and transmits to the WEB terminal diagnosis display interface, and the WEB terminal diagnosis display interface displays the information: "The current triggered protection action is caused by real fault", otherwise the discrimination unit generates a suspected fault signal and transmits to the WEB terminal diagnosis display interface, and the WEB terminal diagnosis display interface displays the information: "The current triggered protection action is caused by suspected fault", execute S405;

[0088] S405: End discrimination.

[0089] Among them, the other interval discrimination strategy includes the following specific steps:

[0090] S40301: Calculate the real fault metric value of the protection action set, the calculation method is as follows:

[0091]

[0092] wherein C TRUE represents the real fault metric value of the protection action set; P(D→H TURE ) represents the occurrence rate of judging the occurrence of the real fault by the protection action set; P(D→H SUSP ) represents the occurrence rate of judging the occurrence of the suspected fault by the protection action set; H TURE represents the real fault event, H SUSP represents the suspected fault event, P(H TURE ) represents the occurrence rate of causing the protection action due to the real fault in the case that the voltage level of the fault interval is 110 kV, which is a priori value; P(H SUSP ) represents the occurrence rate of causing the protection action due to the suspected fault in the case that the voltage level of the fault interval is 110 kV, which is a priori value; D i represents the i-th subset of the protection action set D; D represents the protection action set; P(D i ) represents the occurrence rate of the protection action set being D i in the case of the occurrence of the protection event, P(D i |H TURE ) represents the occurrence rate of the protection action set being D i in the case of the occurrence of the real fault event; P(D i |H SUSP ) represents the occurrence rate of the protection action set being D i in the case of the occurrence of the suspected fault event; all subsets of the protection action set D are exhausted, thereby obtaining all D i .

[0093] wherein the occurrence of the real fault event refers to the occurrence of the protection action due to the real fault in the case that the voltage level of the fault interval is 110 kV; the occurrence of the suspected fault event refers to the occurrence of the protection action due to the suspected fault in the case that the voltage level of the fault interval is 110 kV, and the suspected fault includes: the protection action due to the test protection action, the protection action due to the disturbance.

[0094] The real fault includes: short circuit, grounding, overload, voltage sag that do not conform to the normal operation state of the power grid;

[0095] The disturbance includes: change of the steady-state operating point of the system, large-scale power dispatching, operation in the process of equipment maintenance, communication interference;

[0096] S40302: judging whether the real fault metric value of the protection action set is greater than 1, if yes, determining that it is a real fault; otherwise, determining that it is a suspected fault.

[0097] wherein P(HTURE The calculation method of P(H

[0098]

[0099] P(H SUSP ) is as follows:

[0100]

[0101] P(D i ) is as follows:

[0102]

[0103] P(D i |H TURE ) is as follows:

[0104]

[0105] P(D i |H SUSP ) is as follows:

[0106]

[0107] The data calculated as above are all from the SCADA (Supervisory Control and Data Acquisition) system of the power grid monitoring.

[0108] The SCADA (Supervisory Control and Data Acquisition) system is an important tool for monitoring the power grid, used to collect, process and monitor various operation information of the power grid in real time. The SCADA system usually contains multiple components, including sensors, remote terminal units (RTUs), communication networks and main computer systems in the central control room. Among them, data storage and management are usually responsible by the central database.

[0109] The records of protection actions in the database of the SCADA system generally include the following specific forms of data:

[0110] 1. Event Log:

[0111] Protection actions will be recorded in the event log. The event log usually contains information such as the time stamp of the incident, event type, device identifier and state change. For example, if an overcurrent protection device acts, the event log may record the precise time and location of the protection action, as well as the associated circuit breaker opening state change caused by the action.

[0112] 2. Alarm and Warning:

[0113] When the protection device acts, it will generate an alarm, if the operation and maintenance personnel need to respond immediately, it may be elevated to an emergency alarm. Alarm information is recorded in a special alarm log, including time, alarm level, device name and event description, etc.

[0114] 3. Measurement and Status Data:

[0115] System parameters and device status before and after the protection action are also recorded in the database. These data include voltage, current, power, temperature, etc. measurements, as well as the status information of switching devices such as circuit breakers, disconnectors.

[0116] 4. Sequence Event Recorder (SER) Data:

[0117] The sequence event recorder is a device specifically designed to record protection actions and related power grid event sequences in detail. SER provides details of the sequence of events, which is very useful for accident analysis and fault diagnosis.

[0118] 5. Trend Analysis Data:

[0119] Some systems will conduct statistical analysis on the frequency, duration and consequences of protection actions, etc. to identify specific trends or potential problems in the power grid.

[0120] These data in the database will be organized into tables, records and fields, and managed using standard database management systems such as SQL Server, Oracle, MySQL, etc. Security is also an important consideration in database design, so appropriate access control mechanisms and encryption measures need to be implemented to protect sensitive data.

[0121] In addition to real-time monitoring, the database of the SCADA system enables power grid operators to analyze historical data to improve system performance, optimize response processes and improve future system design. Through accident playback and simulation analysis, the background, causes and effects of protection action can be understood in depth, thereby improving the reliability and resilience of the power grid.

[0122] Other interval discrimination strategies distinguish between maintenance and failure through the disturbance data characteristics of other intervals; through the effectiveness reasoning, the effectiveness reasoning process is based on the connection between protection actions, thereby increasing the realistic basis for determining the authenticity of the failure. In the protection action set, there are various protection action combinations (subsets of protection actions), which have reference value for authenticity discrimination. All protection combinations in the protection action set are used for exhaustive enumeration, and the occurrence rates of protection combination calculated real failure and suspected failure are calculated respectively, and finally accumulated, which can fully utilize the information value in the protection action set.

[0123] The fault interval expansion discrimination strategy includes the following specific steps:

[0124] S40401: query the protection device fault quantity information of the protection action of the protection action set, and generate the protection device fault quantity information of the other protection actions, including: distance measurement, fault phase, fault voltage, fault current, and zero sequence current;

[0125] S40402: calculate the correlation value of the other protection actions in the protection action set and the triggered protection action, wherein the other protection actions are the protection actions in the protection action set excluding the triggered protection action, and the calculation method is as follows:

[0126]

[0127] wherein G SUM represents the correlation value of the other protection action and the triggered protection action, j represents the number of the other protection action, U represents the set of the number of the other protection action, A j represents the fault device fault quantity information of the jth other protection action, A0 represents the fault device fault quantity information of the triggered protection action, and N represents the number of the other protection actions in the protection action set; A j represents the intersection of the fault device fault quantity information of the jth other protection action and the fault device fault quantity information of the triggered protection action; A j represents the union of the fault device fault quantity information of the jth other protection action and the fault device fault quantity information of the triggered protection action; for example: the distance measurement, fault phase, fault voltage, and fault current of the fault device fault quantity information of the first other protection action and the fault device fault quantity information of the triggered protection action are the same, the zero sequence current is different, and the fault device fault quantity information of the other protection action and the fault device fault quantity information of the triggered protection action are only distance measurement, fault phase, fault voltage, fault current, and zero sequence current, then A1∩A0 is 4, and A1∪A0 is 6;

[0128] S40403: judging whether the correlation value between the other protection actions and the protection action triggered is greater than the correlation value threshold, if yes, determining that it is a real fault; otherwise, determining that it is a suspected fault. The correlation value threshold is a constant value, generally 0.8.

[0129] The application provides a comprehensive view by collecting the operation information of each protection device, which can be used for further analyzing the fault, which helps to preliminarily determine whether the fault occurred is a real fault; the correlation value calculation provides a quantitative method, by comparing the similarity of the fault data of different protection actions, it can assist in judging whether they are in response to the same fault; which helps to identify the logical association between each protection action and evaluate whether they are in response to the same fault location; the preset correlation value threshold is used to evaluate the correlation between the other protection actions and the protection action triggered, to determine whether it is a real fault or a suspected fault.

Claims

1. A power grid fault authenticity identification system based on the timing of protection action events, characterized in that, include: Query module and protection action management module; The query module monitors the protection device. When the protection device initiates a protection action, it records this action as a triggered protection action and records the protection action information, including: fault interval, voltage level of the fault interval, and protection action time. Based on the protection action information, it generates the interval and time window to be queried and transmits the triggered protection action information, the interval to be queried, and the time window to the protection action management module. The protection action management module then queries the time window based on the triggered protection action information, the interval to be queried, and the time window transmitted by the query module. If a total fault signal exists within the window, a real fault signal is generated and transmitted to the WEB-based diagnostic display interface. The WEB-based diagnostic display interface displays the information: "The current protection action was triggered due to a real fault." Otherwise, the protection actions for the required interval are queried to obtain a set of protection actions. This set of protection actions is then filtered to remove those that are test protection actions within the time window, resulting in a filtered set of protection actions. Based on this filtered set, a fault signal is generated and transmitted to the WEB-based diagnostic display interface, where it is displayed accordingly. When the voltage level of the fault interval is 220kV or above, the intervals to be queried are the fault interval, other intervals of the fault interval, and related intervals of the fault interval. The start time of the time window is the time when the protection action is triggered, and the end time of the time window is the time when the protection action is triggered plus 10 seconds. When the voltage level of the fault interval is 110kV, the interval to be queried is the other intervals of the fault interval. The start time of the time window is the time when the protection action is triggered, and the end time of the time window is the time when the protection action is triggered plus 10 seconds. When the voltage level of the fault interval is 35kV or below, the interval to be queried is the fault interval. The start time of the time window is the time when the protection action is triggered, and the end time of the time window is the time when the protection action is triggered plus 160 seconds.

2. The power grid fault authenticity identification system based on protection action event timing as described in claim 1, characterized in that, Other intervals of the fault interval are intervals other than the power grid fault interval under the same substation. The related intervals of the fault interval are intervals where there are two substations at both ends of the same line. When the protection devices of the A set of protection and the B set of protection of one substation start protection action, the interval where the A set of protection and the B set of protection of the other substation are located.

3. The power grid fault authenticity identification system based on protection action event timing as described in claim 1, characterized in that, The query module includes: an interval storage unit, a query unit, and a time window generation unit; among which, Interval storage unit: used to store fault intervals, as well as related intervals and other intervals of the fault interval; Query Unit: Used as an index to search the interval storage unit using the fault interval that triggered the protection action. When the voltage level of the fault interval is 220kV or above, it searches for related intervals and other intervals of the fault interval, and transmits the fault interval, related intervals, and other intervals of the fault interval to the protection action management module; when the voltage level of the fault interval is 110kV, it searches for other intervals of the fault interval and transmits them to the protection action management module; when the voltage level of the fault interval is 35kV or below, it transmits the fault interval to the protection action management module. Time window generation unit: Used to generate a time window based on the action time of the protection trigger. The time window generation rules are as follows: When the voltage level of the fault interval is 220kV or above, or the voltage level of the fault interval is 110kV, the start time of the time window is the action time of the protection trigger, and the end time of the time window is the action time of the protection trigger plus 10 seconds; when the voltage level of the fault interval is 35kV or below, the start time of the time window is the action time of the protection trigger, and the end time of the time window is the action time of the protection trigger plus 160 seconds. After the time window generation unit generates the time window, it transmits the time window to the protection action management module.

4. The power grid fault authenticity identification system based on protection action event timing as described in claim 1, characterized in that, The protection action management module includes: a protection action storage unit, a filtering unit, and a signal generation unit; among which, Protection action storage unit: used to store protection actions and total fault signals; This is used to generate a time window based on the time window transmission unit, query the total fault signal within the time window, and if a total fault signal exists, generate a real fault signal and transmit it to the WEB diagnostic display interface. The WEB diagnostic display interface displays the information: "The current protection action is triggered due to a real fault"; otherwise, it executes: based on the interval to be queried transmitted by the query unit and the time window transmitted by the time window generation unit, it queries the protection actions within the interval to be queried within the time window, obtains the protection action set, and transmits the protection action set to the filtering unit. Filtering unit: Used to filter the set of protection actions transmitted from the protection action storage unit to obtain a filtered set of protection actions. The filtering rule is to remove protection actions that are test protection actions within the time window from the set of protection actions; and to transmit the filtered set of protection actions to the discrimination unit. Judgment Unit: Used to make judgments based on the filtered protection action set: When the voltage level of the fault interval is 220kV and above, the judgment unit generates a real fault signal and transmits it to the WEB diagnostic display interface when the following two situations exist; otherwise, the judgment unit generates a suspected fault signal and transmits it to the WEB diagnostic display interface: Situation 1: The filtered protection action set contains protection actions from other intervals and protection actions from the same interval at the same time; Situation 2: The filtered protection action set contains protection actions from other intervals and protection actions from related intervals at the same time. When the voltage level of the fault interval is 110kV, the discrimination unit determines whether it is a real fault based on other interval discrimination strategies. If it is a real fault, the discrimination unit generates a real fault signal and transmits it to the WEB diagnostic display interface; otherwise, the discrimination unit generates a suspected fault signal and transmits it to the WEB diagnostic display interface. When the voltage level of the fault interval is 35kV or below, the discrimination unit determines whether it is a real fault based on the fault interval extended discrimination strategy. If it is a real fault, the discrimination unit generates a real fault signal and transmits it to the WEB diagnostic display interface; otherwise, the discrimination unit generates a suspected fault signal and transmits it to the WEB diagnostic display interface.

5. A method for identifying the authenticity of a power grid fault based on the timing of protection action events as described in claim 1, characterized in that, Includes the following steps: Step 1: The query module monitors the protection device. When the protection device initiates a protection action, it records the protection action as a triggered protection action and records the protection action information that triggered the protection action, including: fault interval, voltage level of the fault interval, and protection action time. Based on the protection action information, it generates the interval and time window to be queried and transmits the protection action information, the interval and time window to be queried to the protection action management module. Step 2: The protection action management module queries the total fault signal within the time window generated by the time window generation unit based on the time window time window. If a total fault signal exists, a real fault signal is generated and transmitted to the WEB diagnostic display interface. The WEB diagnostic display interface displays the information: "The current protection action was triggered due to a real fault"; otherwise, the protection action management module queries the protection actions within the time window time window based on the interval to be queried transmitted by the query module and the time window time window generated by the time window generation unit, thus obtaining a set of protection actions. Step 3: The protection action management module filters the protection action set, removing protection actions that are test protection actions within the time window, thus obtaining the filtered protection action set. Step 4: The protection action management module judges the filtered protection action set and generates a fault signal, which is then transmitted to the WEB-based diagnostic display interface.

6. The method for identifying the authenticity of power grid faults based on the timing of protection action events as described in claim 5, characterized in that, In step 1, the query module monitors the protection device and generates the necessary content to the protection action management module based on the protection action information. This includes the following steps: Step 11: The query module monitors the protection device. When the protection device initiates a protection action, it records the protection action as a triggered protection action and records the protection action information that triggered the protection action, including: fault interval, voltage level of the fault interval, and protection action time. Step 12: The query module determines the voltage level of the fault interval that triggered the protection action; when the voltage level of the fault interval that triggered the protection action is 220kV or above, proceed to step 13; when the voltage level of the fault interval that triggered the protection action is 110kV, proceed to step 14; when the voltage level of the fault interval that triggered the protection action is 35kV or below, proceed to step 15. Step 13: The query module generates the intervals and time windows to be queried. The intervals to be queried are the fault interval, other intervals of the fault interval, and related intervals of the fault interval. The start time of the time window is the action time that triggers the protection action, and the end time of the time window is the action time that triggers the protection action plus 10 seconds. The query module transmits the intervals and time windows to be queried to the protection action management module and executes step 16. Step 14: The query module generates the interval and time window to be queried. The interval to be queried is the other intervals of the fault interval. The start time of the time window is the action time that triggers the protection action, and the end time of the time window is the action time that triggers the protection action plus 10 seconds. The query module transmits the interval and time window to be queried to the protection action management module and executes step 16. Step 15: The query module generates the interval and time window to be queried. The interval to be queried is the fault interval, the start time of the time window is the action time that triggers the protection action, and the end time of the time window is the action time that triggers the protection action plus 160 seconds. The query module transmits the interval and time window to be queried to the protection action management module and executes step 16. Step 16: End of Step 1.

7. The method for identifying the authenticity of power grid faults based on the timing of protection action events as described in claim 5, characterized in that, In step 4, the protection action management module makes a judgment based on the filtered set of protection actions and generates a fault signal, which is then transmitted to the WEB-based diagnostic display interface. This specifically includes the following steps: Step 41: Determine the voltage level of the fault interval that triggered the protection action. If the voltage level of the fault interval is 220kV or above, proceed to step 42; if the voltage level of the fault interval is 110kV, proceed to step 43; if the voltage level of the fault interval is 35kV or below, proceed to step 44. Step 42: When either of the following two situations exists, the discrimination unit generates a real fault signal and transmits it to the WEB diagnostic display interface, which displays the information: "The current triggered protection action is caused by a real fault." Otherwise, the discrimination unit generates a suspected fault signal and transmits it to the WEB diagnostic display interface, which displays the information: "The current triggered protection action is caused by a suspected fault": Situation 1: The filtered protection action set contains both protection actions from other intervals and protection actions from the same interval; Situation 2: The filtered protection action set contains both protection actions from other intervals and protection actions from related intervals. Proceed to step 45. Step 43: The discrimination unit determines whether it is a real fault based on other interval discrimination strategies. If it is a real fault, the discrimination unit generates a real fault signal and transmits it to the WEB diagnostic display interface. The WEB diagnostic display interface displays the information: "The current protection action is triggered due to a real fault". Otherwise, the discrimination unit generates a suspected fault signal and transmits it to the WEB diagnostic display interface. The WEB diagnostic display interface displays the information: "The current protection action is triggered due to a suspected fault". Then proceed to step 45. Step 44: The discrimination unit expands the discrimination strategy according to the fault interval to determine whether it is a real fault. If it is a real fault, the discrimination unit generates a real fault signal and transmits it to the WEB diagnostic display interface. The WEB diagnostic display interface displays the information: "The current protection action is triggered due to a real fault". Otherwise, the discrimination unit generates a suspected fault signal and transmits it to the WEB diagnostic display interface. The WEB diagnostic display interface displays the information: "The current protection action is triggered due to a suspected fault". Then proceed to step 45. Step 45: End the discrimination process.

8. The method for identifying the authenticity of power grid faults based on the timing of protection action events as described in claim 7, characterized in that, In step 43, the other interval discrimination strategy specifically involves calculating the actual fault metric value of the protection action set, using the following calculation method: Among them, C TRUE P(D→H) represents the actual fault metric of the protection action set. TURE P(D→H) represents the actual fault occurrence rate determined by the set of protection actions; SUSP H represents the incidence rate of suspected faults determined by the set of protection actions; TURE H represents a real fault event. SUSP Indicates a suspected fault event, P(H) TURE P(H) represents the probability of protection operation due to a real fault when the voltage level of the fault interval is 110kV; SUSP This represents the incidence rate of protection operation due to suspected faults when the voltage level of the fault interval is 110kV; D i P(D) represents the i-th subset of the set of protective actions D; D represents the set of protective actions; P(D) i This indicates that, in the event of a protective event, the set of protective actions is D. i The incidence rate, P(D) i |H TURE This indicates that, in the event of a real fault event, the set of protection actions is D. i The incidence rate; P(D) i |H SUSP This indicates that in the event of a suspected fault, the set of protection actions is D. i The occurrence rate; determine whether the actual fault metric value of the protection action set is greater than 1. If it is greater than 1, it is determined to be a real fault; otherwise, it is determined to be a suspected fault.

9. The method for identifying the authenticity of power grid faults based on the timing of protection action events as described in claim 7, characterized in that, In step 44, the fault interval expansion discrimination strategy is as follows: Query the fault quantity information of the protection devices for the protection actions in the protection action set; generate the fault quantity information of the protection devices for other protection actions, including: distance measurement, fault phase, fault voltage, fault current, and zero-sequence current; calculate the correlation value between other protection actions in the protection action set and the triggered protection action, where other protection actions are protection actions in the protection action set that do not include the triggered protection action. The calculation method is as follows: Among them, G SUM This represents the value related to other protection actions and the triggering of those actions, where j represents the number of the other protection action, U represents the set of numbers of the other protection actions, and A represents the value related to the triggering of those actions. j A0 represents the fault quantity information of the faulty device that triggered the protection action, and N represents the number of other protection actions in the protection action set. It is determined whether the correlation value between other protection actions and the triggering protection action is greater than the correlation value threshold. If it is greater than the correlation value threshold, it is determined to be a real fault; otherwise, it is determined to be a suspected fault. The correlation value threshold is 0.8.

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