Detection method and device for non-full-phase operation of generator end circuit breaker GCB

Abstract

The present application proposes a detection method and device for the non-full-phase operation of the GCB circuit breaker at the generator end, which relates to the field of relay protection of power systems. The method obtains the corresponding monitoring data of the generator during the grid connection process or the decoupling process; determines whether the GCB has a position change; if the GCB has a position change, determines the starting time of the GCB position change, and within a preset time period starting from the starting time, if it is determined according to the monitoring data that the generator has a primary circuit break, then further determines whether the negative sequence current corresponding to the generator end reaches the negative sequence current threshold; if the negative sequence current reaches the negative sequence current threshold, it is determined that the GCB of the generator is in a non-full-phase operation state. The present application realizes the accurate identification of the non-full-phase of the generator GCB in the low-load stage during the initial stage of the generator grid connection or the normal shutdown decoupling process, which helps to timely discover the abnormal operation state of the generator and prompt the necessary maintenance and repair measures.

Description

Technical Field

[0001] The present application relates to the field of relay protection for electric power systems, and in particular to a method and device for detecting non-full-phase operation of a generator-end circuit breaker GCB. Background Art

[0002] Taking into account the needs of different stages of power plant operation (commissioning stage, normal operation stage, and abnormal operation stage), large generator transformer groups are generally equipped with generator circuit breakers (GCB) at the generator outlet. Hydropower stations play an important role in peak load regulation of my country's power system. Since hydropower stations bear the heavy burden of peak load regulation of regional power grids, frequent start and stop are the prominent characteristics of the operation mode of hydropower units. According to incomplete statistics, the number of hydropower station units connected to the grid or disconnected through GCB reaches more than 100 times a year. It is generally believed that the three-phase linkage mechanism machine-side circuit breaker will not have non-full-phase closing or opening conditions, but for hydropower units that have been in operation for more than 10 years, with the increase in the number of operations, wear of the mechanical structure or design defects, the number of closing and opening times is close to the mechanical life of the GCB, resulting in more and more cases of non-full-phase failure of the unit.

[0003] At present, most of the hydropower units that have been put into operation, if non-full-phase operation occurs during the process of grid connection or normal disconnection, often use the negative sequence current protection of the generator to isolate the fault. In the early stage of grid connection or the low-load stage of normal disconnection, the negative sequence current is too small to reach the fault range of the generator negative sequence over-protection device, resulting in non-full-phase operation of the hydropower generator set. On the one hand, the negative sequence current generated by this operation mode will induce a double frequency current in the rotor, which will form local high temperature in the parts with large rotor contact resistance, and then burn the rotor; on the other hand, the negative sequence magnetic field will cause the vibration of the unit to increase, which may cause metal fatigue and mechanical damage. Therefore, exploring a new method for detecting non-full-phase GCB of hydropower station generators plays a vital role in the reliable operation of hydropower units. Summary of the invention

[0004] The present application aims to solve one of the technical problems in the related art at least to some extent.

[0005] To this end, one purpose of the present application is to propose a detection method for non-full-phase operation of a generator-end circuit breaker GCB, by obtaining corresponding monitoring data of the generator during the grid-connected process or the disconnected process, wherein the monitoring data includes a first low-frequency phase voltage and a first low-frequency open zero-sequence voltage corresponding to the generator end, and a second low-frequency phase voltage and a second low-frequency open zero-sequence voltage corresponding to the low-voltage side of the generator main transformer; judging whether the position of the GCB has changed according to the closing position and the opening position of the circuit breaker GCB at the generator end; if it is judged that the position of the GCB has changed, determining the starting time when the position of the GCB has changed, and judging whether the generator has a primary circuit break according to the monitoring data within a preset time length starting from the starting time; if it is judged that the generator has a primary circuit break, further judging whether the negative sequence current corresponding to the generator end reaches the negative sequence current threshold; if the negative sequence current corresponding to the generator end reaches the negative sequence current threshold, determining that the GCB of the generator is in a non-full-phase operation state.

[0006] The second objective of the present application is to provide a detection device for non-full-phase operation of a generator end circuit breaker GCB.

[0007] The third objective of the present application is to provide an electronic device.

[0008] A fourth object of the present application is to provide a non-transitory computer-readable storage medium.

[0009] A fifth object of the present application is to provide a computer program product.

[0010] To achieve the above-mentioned purpose, the first aspect of the embodiment of the present application proposes a detection method for non-full-phase operation of a generator-end circuit breaker GCB, including: obtaining corresponding monitoring data of the generator during the grid-connected process or the disconnected process, wherein the monitoring data includes a first low-frequency phase voltage and a first low-frequency open zero-sequence voltage corresponding to the generator end, and a second low-frequency phase voltage and a second low-frequency open zero-sequence voltage corresponding to the low-voltage side of the generator main transformer; judging whether the position of the GCB has changed according to the closing position and the opening position of the generator-end circuit breaker GCB; if it is judged that the GCB has changed its position, determining the starting time when the GCB has changed its position, and judging whether the generator has a primary circuit break according to the monitoring data within a preset time length starting from the starting time; if it is judged that the generator has a primary circuit break, further judging whether the negative sequence current corresponding to the generator end reaches the negative sequence current threshold; if the negative sequence current corresponding to the generator end reaches the negative sequence current threshold, it is determined that the GCB of the generator is in a non-full-phase operation state.

[0011] According to one embodiment of the present application, judging whether a primary circuit of a generator is broken is determined based on monitoring data, including: presetting a low-frequency phase voltage judgment standard, a first low-frequency open zero-sequence voltage judgment standard and a second low-frequency open zero-sequence voltage judgment standard corresponding to the monitoring data; judging whether the monitoring data meets the low-frequency phase voltage judgment standard; judging whether the monitoring data meets the first low-frequency open zero-sequence voltage judgment standard; judging whether the monitoring data meets the second low-frequency open zero-sequence voltage judgment standard; judging whether a primary circuit of the generator is broken, including: if it is judged that the monitoring data simultaneously meets the low-frequency phase voltage judgment standard, the first low-frequency open zero-sequence voltage judgment standard and the second low-frequency open zero-sequence voltage judgment standard, then it is determined that a primary circuit of the generator is broken.

[0012] According to one embodiment of the present application, determining whether the monitoring data meets the low-frequency phase voltage judgment standard includes: for each phase, determining the corresponding first voltage threshold based on the corresponding first low-frequency phase voltage and a preset first amplitude coefficient; for each phase, obtaining the difference between the corresponding first low-frequency phase voltage and the corresponding second low-frequency phase voltage; for each phase, determining whether the absolute value of the corresponding difference is greater than the corresponding first voltage threshold; if the absolute values ​​of the corresponding differences of the three phases are all greater than their respective corresponding first voltage thresholds, determining that the monitoring data meets the low-frequency phase voltage judgment standard.

[0013] According to one embodiment of the present application, determining whether the monitoring data meets the first low-frequency open zero-sequence voltage judgment standard includes: determining the second voltage threshold based on the first low-frequency phase voltage, a preset second amplitude coefficient, and a preset multiple coefficient; comparing the first low-frequency open zero-sequence voltage with the second voltage threshold, if the first low-frequency open zero-sequence voltage is less than the second voltage threshold, determining that the monitoring data meets the first low-frequency open zero-sequence voltage judgment standard.

[0014] According to one embodiment of the present application, determining whether the monitoring data meets the second low-frequency open zero-sequence voltage judgment standard includes: determining the third voltage threshold based on the second low-frequency phase voltage, a preset third amplitude coefficient, and a preset multiple coefficient; comparing the second low-frequency open zero-sequence voltage with the third voltage threshold, if the second low-frequency open zero-sequence voltage is less than the third voltage threshold, determining that the monitoring data meets the second low-frequency open zero-sequence voltage judgment standard.

[0015] According to one embodiment of the present application, determining whether the negative sequence current corresponding to the generator terminal reaches a negative sequence current threshold includes: obtaining the terminal phase current corresponding to the generator terminal, and extracting the negative sequence current corresponding to the generator terminal based on the terminal phase current; presetting a negative sequence current threshold to determine whether the negative sequence current reaches the negative sequence current threshold.

[0016] According to an embodiment of the present application, after determining whether the position of the generator-end circuit breaker GCB changes according to the closing position and the opening position of the GCB, the method further includes: if it is determined that the GCB does not change its position, continuously acquiring monitoring data corresponding to the generator.

[0017] To achieve the above-mentioned purpose, the second embodiment of the present application proposes a detection device for non-full-phase operation of a generator-end circuit breaker GCB, including: a data acquisition module, used to obtain corresponding monitoring data of the generator during the grid-connected process or the decoupling process, wherein the monitoring data includes a first low-frequency phase voltage and a first low-frequency open zero-sequence voltage corresponding to the generator end, and a second low-frequency phase voltage and a second low-frequency open zero-sequence voltage corresponding to the low-voltage side of the generator main transformer; a position judgment module, used to judge whether the position of the GCB has changed according to the closing position and the opening position of the GCB of the generator end circuit breaker; a circuit break judgment module, used to determine the starting time of the GCB position change if it is judged that the GCB has changed its position, and judge whether the generator has a primary circuit break according to the monitoring data within a preset time length starting from the starting time; a negative sequence current judgment module, used to further judge whether the negative sequence current corresponding to the generator end reaches the negative sequence current threshold if it is judged that the generator has a primary circuit break; a state determination module, used to determine that the GCB of the generator is in a non-full-phase operation state if the negative sequence current corresponding to the generator end reaches the negative sequence current threshold.

[0018] According to one embodiment of the present application, the loop disconnection judgment module is also used to: pre-set the low-frequency phase voltage judgment standard, the first low-frequency open zero-sequence voltage judgment standard and the second low-frequency open zero-sequence voltage judgment standard corresponding to the monitoring data; judge whether the monitoring data meets the low-frequency phase voltage judgment standard; judge whether the monitoring data meets the first low-frequency open zero-sequence voltage judgment standard; judge whether the monitoring data meets the second low-frequency open zero-sequence voltage judgment standard. If it is determined that the monitoring data simultaneously meets the low-frequency phase voltage judgment standard, the first low-frequency open zero-sequence voltage judgment standard and the second low-frequency open zero-sequence voltage judgment standard, it is determined that a loop disconnection has occurred in the generator.

[0019] According to one embodiment of the present application, the loop disconnection judgment module is also used to: for each phase, determine the corresponding first voltage threshold according to the corresponding first low-frequency phase voltage and the preset first amplitude coefficient; for each phase, obtain the difference between the corresponding first low-frequency phase voltage and the corresponding second low-frequency phase voltage; for each phase, judge whether the absolute value of the corresponding difference is greater than the corresponding first voltage threshold; if the absolute values ​​of the corresponding differences of the three phases are all greater than their respective corresponding first voltage thresholds, it is determined that the monitoring data meets the low-frequency phase voltage judgment standard.

[0020] According to one embodiment of the present application, the loop break judgment module is also used to: determine the second voltage threshold based on the first low-frequency phase voltage, a preset second amplitude coefficient, and a preset multiple coefficient; compare the first low-frequency open zero-sequence voltage with the second voltage threshold, and if the first low-frequency open zero-sequence voltage is less than the second voltage threshold, determine that the monitoring data meets the first low-frequency open zero-sequence voltage judgment standard.

[0021] According to one embodiment of the present application, the loop break judgment module is also used to: determine the third voltage threshold based on the second low-frequency phase voltage, a preset third amplitude coefficient, and a preset multiple coefficient; compare the second low-frequency open zero-sequence voltage with the third voltage threshold, and if the second low-frequency open zero-sequence voltage is less than the third voltage threshold, determine that the monitoring data meets the second low-frequency open zero-sequence voltage judgment standard.

[0022] According to one embodiment of the present application, the negative-sequence current judgment module is also used to: obtain the machine-end phase current corresponding to the generator machine-end, and extract the negative-sequence current corresponding to the generator machine-end based on the machine-end phase current; preset a negative-sequence current threshold to determine whether the negative-sequence current reaches the negative-sequence current threshold.

[0023] According to an embodiment of the present application, the data acquisition module is further used to: if it is determined that the position of the GCB has not changed, then continuously acquire the monitoring data corresponding to the generator.

[0024] To achieve the above-mentioned purpose, the third aspect embodiment of the present application proposes an electronic device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to implement the detection method of non-full-phase operation of the generator end circuit breaker GCB as described in the first aspect embodiment of the present application.

[0025] To achieve the above-mentioned purpose, the fourth aspect embodiment of the present application proposes a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to implement the detection method of non-full-phase operation of the generator end circuit breaker GCB as described in the first aspect embodiment of the present application.

[0026] To achieve the above-mentioned purpose, the fifth aspect embodiment of the present application proposes a computer program product, including a computer program, which, when executed by a processor, implements the detection method for non-full-phase operation of the generator end circuit breaker GCB as described in the first aspect embodiment of the present application.

[0027] The present application achieves at least the following beneficial effects: the present application realizes accurate identification of non-full-phase GCB of the generator occurring in the low-load stage during the initial stage of generator grid connection or normal shutdown and decoupling, which helps to timely discover the abnormal operating state of the generator, prompting the necessary maintenance and repair measures to be taken, and can avoid rotor burning and increased unit vibration caused by long-term non-full-phase operation of the generator under low-load conditions of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0029] Figure 1 It is a schematic diagram of an exemplary implementation of a method for detecting non-full-phase operation of a generator end circuit breaker GCB shown in the present application.

[0030] Figure 2 This is a schematic diagram of the installation position of a generator end circuit breaker GCB shown in the present application.

[0031] Figure 3 It is a schematic diagram of an exemplary implementation of a method for detecting non-full-phase operation of a generator end circuit breaker GCB shown in the present application.

[0032] Figure 4 It is a schematic diagram of a detection device for non-full-phase operation of a generator end circuit breaker GCB shown in the present application.

[0033] Figure 5 It is a schematic diagram of an electronic device shown in one embodiment of the present application. DETAILED DESCRIPTION

[0034] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0035] Figure 1 is a schematic diagram of an exemplary embodiment of a method for detecting non-full-phase operation of a generator end circuit breaker GCB shown in the present application, such as Figure 1 As shown, the detection method of the non-full-phase operation of the generator end circuit breaker GCB comprises the following steps:

[0036] S101, obtaining corresponding monitoring data of the generator during the grid-connected process or the disconnected process, wherein the monitoring data includes a first low-frequency phase voltage and a first low-frequency open zero-sequence voltage corresponding to the generator end, and a second low-frequency phase voltage and a second low-frequency open zero-sequence voltage corresponding to the low-voltage side of the generator main transformer.

[0037] Figure 2 This is a schematic diagram of the installation position of a generator end circuit breaker GCB shown in this application, combined with Figure 2 To understand that in this application, when obtaining the corresponding monitoring data of the generator during the grid connection process or the disconnection process, it is necessary to obtain the first low-frequency phase voltage U monitored by the generator terminal PT1 Gk (k = A, B, C), the first low-frequency open zero-sequence voltage U corresponding to the generator end G0 , the second low-frequency phase voltage U monitored by PT2 on the low-voltage side of the generator main transformer Tk (k=A, B, C), the second low-frequency open zero-sequence voltage U corresponding to the low-voltage side of the generator main transformer T0 .

[0038] S102, judging whether the position of the generator end circuit breaker GCB changes according to the closing position and the opening position of the GCB.

[0039] The closing position HZ and the opening position FZ of the generator end circuit breaker GCB are obtained, and it is determined whether the position of the GCB changes according to the closing position and the opening position of the generator end circuit breaker GCB.

[0040] In the present application, the position change of GCB refers to the change of GCB position during the generator grid-connection process (from open to closed) or the change of GCB closing position of the circuit breaker during the disconnection process (from closed to open), that is, it refers to limiting the time period when the generator's non-full-phase operation state occurs to the initial grid-connection or normal disconnection process, so as to avoid malfunction of the unit due to misjudgment of the unit's GCB non-full-phase operation due to non-full-phase operation on the power grid system side.

[0041] S103, if it is determined that the GCB has a position change, determine the start time of the GCB position change, and determine whether the generator has a primary circuit disconnection according to the monitoring data within a preset time period starting from the start time.

[0042] Among them, to determine whether the generator has a primary circuit disconnection based on the monitoring data, it is necessary to pre-set the low-frequency phase voltage judgment standard, the first low-frequency open zero-sequence voltage judgment standard and the second low-frequency open zero-sequence voltage judgment standard corresponding to the monitoring data. After setting the three standards, the next step is to determine whether the primary circuit is disconnected. The specific steps are as follows:

[0043] (1) Determine whether the monitoring data meets the low-frequency phase voltage judgment standard. Specifically:

[0044] For each phase, according to the corresponding first low-frequency phase voltage U Gk The first voltage threshold U corresponding to the preset first amplitude coefficient K1 is determinedset1 .

[0045] Then, for each phase, the corresponding first low-frequency phase voltage U is obtained. Gk The second low-frequency phase voltage U corresponding to this Tk The difference between them, that is, the difference is U Gk -U Tk .

[0046] Then, for each phase, it is determined whether the absolute value of the corresponding difference is greater than the corresponding first voltage threshold.

[0047] If the absolute values ​​of the differences corresponding to the three phases are all greater than their respective corresponding first voltage thresholds, that is, the three phases all satisfy |U Gk -U Tk |>U set1 (k=A, B, C), it is determined that the monitoring data meets the low-frequency phase voltage judgment standard.

[0048] (2) Determine whether the monitoring data meets the first low-frequency open zero-sequence voltage judgment standard. Specifically:

[0049] Under normal working conditions, the first low-frequency phase voltage U Gk (k=A, B, C) means the low-frequency phase of each phase is the same, and the first low-frequency open zero-sequence voltage U of PT1 at the generator end G0 Should be 3 times U Gk ; Under fault conditions, the first low-frequency open zero-sequence voltage U of PT1 at the generator end G0 Less than 3 times U Gk In this application, according to the first low-frequency phase voltage U Gk , a preset second amplitude coefficient K2, a preset multiple coefficient (generally set to 3), and a second voltage threshold U set2 .in:

[0050] U set2 =U Gk *K2*3

[0051] The first low-frequency open zero-sequence voltage U G0 With the second voltage threshold U set2 For comparison, if the first low-frequency open zero-sequence voltage U G0 Less than the second voltage threshold U set2 , that is, if U G0 set2 , it is determined that the monitoring data meets the first low-frequency open zero-sequence voltage judgment standard.

[0052] (3) Determine whether the monitoring data meets the second low-frequency open zero-sequence voltage judgment standard. Specifically:

[0053] ​Under normal working conditions, the second low-frequency phase voltage U Tk (k=A, B, C) means the low-frequency phase of each phase is the same, and the second low-frequency open zero-sequence voltage U of PT2 on the low-voltage side of the main transformer T0 Should be 3 times U Tk ; Fault condition, the second low-frequency open zero-sequence voltage U of PT2 on the low-voltage side of the main transformer T0 Less than 3 times U Tk In this application, according to the second low-frequency phase voltage U Tk (k=A, B, C), a preset third amplitude coefficient K3, a preset multiplication coefficient (generally set to 3), and a third voltage threshold U set3 .

[0054] in:

[0055] U set3 =U Tk *K3*3

[0056] The second low-frequency open zero-sequence voltage U T0 With the third voltage threshold U set3 For comparison, if the second low-frequency open zero-sequence voltage U T0 Less than the third voltage threshold U set3 , it is determined that the monitoring data meets the second low-frequency open zero-sequence voltage judgment standard.

[0057] S104: If it is determined that the primary circuit of the generator is disconnected, it is further determined whether the negative sequence current corresponding to the generator terminal reaches a negative sequence current threshold.

[0058] If it is determined that the monitoring data simultaneously meets the low-frequency phase voltage judgment standard, the first low-frequency open zero-sequence voltage judgment standard and the second low-frequency open zero-sequence voltage judgment standard, it is determined that the primary circuit of the generator is broken.

[0059] Since the primary circuit disconnection state includes the primary main circuit disconnection and the primary PT circuit disconnection, in this application, in order to further determine that the primary main circuit is disconnected, the generator terminal phase current I corresponding to the generator terminal is further obtained. GK (k = A, B, C), and based on the phase current at the generator end, the negative sequence current I corresponding to the generator end is extracted according to the symmetrical component method G2 ;

[0060] In the initial stage of generator grid connection or normal shutdown and decoupling, the generator set is operated in a non-full-phase state due to the break of the three-linkage mechanism of the generator end circuit breaker. The negative sequence current of the hydro-turbine generator set is affected by the load of the set. The greater the load, the greater the negative sequence current. Because the load current of the set is too small to meet the negative sequence overcurrent protection condition of the generator in the initial stage of grid connection or normal shutdown and decoupling, the unit has a protection dead zone. In this application, a smaller negative sequence current threshold I is constructed according to the negative sequence current characteristic quantity in the initial stage of grid connection or normal shutdown and decoupling. 2set1 .

[0061] Determine whether the negative sequence current reaches the negative sequence current threshold.

[0062] S105: If the negative sequence current corresponding to the generator terminal reaches the negative sequence current threshold, it is determined that the GCB of the generator is in a non-full-phase operation state.

[0063] If the negative sequence current corresponding to the generator terminal reaches the negative sequence current threshold, that is, if I G2 ≥I 2set1 , it is determined that the GCB of the generator is in a non-full-phase operation state.

[0064] The present application realizes accurate identification of non-full-phase GCB of the generator during the low-load stage in the initial stage of generator grid connection or normal shutdown and decoupling process, which helps to timely discover the abnormal operating status of the generator and prompt the necessary maintenance and repair measures to avoid rotor burning and increased unit vibration due to long-term non-full-phase operation of the generator under low-load conditions.

[0065] Furthermore, if it is determined that the position of the GCB has not changed, the monitoring data corresponding to the generator is continuously acquired.

[0066] Figure 3 is a schematic diagram of an exemplary embodiment of a method for detecting non-full-phase operation of a generator end circuit breaker GCB shown in the present application, such as Figure 3 As shown, the detection method of the non-full-phase operation of the generator end circuit breaker GCB comprises the following steps:

[0067] During the process of generator grid connection or disconnection, the first low-frequency phase voltage U monitored by the generator terminal PT1 is obtained. Gk (k = A, B, C), the first low-frequency open zero-sequence voltage U corresponding to the generator end G0 .

[0068] Get the second low-frequency phase voltage U monitored by PT2 on the low-voltage side of the generator main transformer Tk (k=A, B, C), the second low-frequency open zero-sequence voltage U corresponding to the low-voltage side of the generator main transformer T0 .

[0069] Obtain the closing position HZ and opening position FZ of the generator end circuit breaker GCB.

[0070] Whether the position of the GCB has changed is determined based on the closing position and opening position of the GCB at the generator end.

[0071] If it is determined that the GCB has changed its position, the start time of the GCB position change is determined, and within the preset time length from the start time (which can also be understood as the start delay time t), it is determined according to the monitoring data whether the generator has a primary circuit disconnection. Among them, when judging whether the generator has a primary circuit disconnection according to the monitoring data, it is necessary to pre-set the low-frequency phase voltage judgment standard corresponding to the monitoring data, the first low-frequency open zero-sequence voltage judgment standard and the second low-frequency open zero-sequence voltage judgment standard as three criteria. The specific setting method is the same as the method described in the above embodiment.

[0072] If it is determined that the monitoring data simultaneously meets the low-frequency phase voltage judgment standard, the first low-frequency open zero-sequence voltage judgment standard and the second low-frequency open zero-sequence voltage judgment standard, it is determined that the primary circuit of the generator is broken.

[0073] Since the primary circuit disconnection state includes the primary main circuit disconnection and the primary PT circuit disconnection, in this application, in order to further determine that the primary main circuit is disconnected, the generator terminal phase current I corresponding to the generator terminal is further obtained. GK (k = A, B, C), and based on the phase current at the generator end, the negative sequence current I corresponding to the generator end is extracted according to the symmetrical component method G2 .

[0074] If the negative sequence current corresponding to the generator terminal reaches the negative sequence current threshold, that is, if I G2 ≥I 2set1 , it is determined that the GCB of the generator is in a non-full-phase operation state.

[0075] Furthermore, if it is determined that the position of the GCB has not changed, the monitoring data corresponding to the generator is continuously acquired.

[0076] Furthermore, if the negative sequence current corresponding to the generator terminal does not reach the negative sequence current threshold, the detection process is terminated.

[0077] Furthermore, if it is monitored that the current time is outside the preset time length starting from the start time, the detection process is terminated.

[0078] Figure 4 Schematic diagram of a detection device for non-full-phase operation of a generator end circuit breaker GCB shown in the present application, such as Figure 4As shown, the detection device 400 for the non-full-phase operation of the generator end circuit breaker GCB includes a data acquisition module 401, a position judgment module 402, a loop disconnection judgment module 403, a negative sequence current judgment module 404 and a state determination module 405, wherein:

[0079] The data acquisition module 401 is used to obtain the corresponding monitoring data of the generator during the grid-connected process or the disconnected process, wherein the monitoring data includes the first low-frequency phase voltage and the first low-frequency open zero-sequence voltage corresponding to the generator end, and the second low-frequency phase voltage and the second low-frequency open zero-sequence voltage corresponding to the low-voltage side of the generator main transformer.

[0080] The position determination module 402 is used to determine whether the position of the generator end circuit breaker GCB changes according to the closing position and the opening position of the GCB.

[0081] The circuit disconnection determination module 403 is used to determine the start time of the GCB position change if it is determined that the GCB position change occurs, and determine whether the generator circuit is disconnected according to the monitoring data within a preset time period starting from the start time.

[0082] The negative sequence current determination module 404 is used to further determine whether the negative sequence current corresponding to the generator terminal reaches a negative sequence current threshold if it is determined that the primary circuit of the generator is disconnected.

[0083] The state determination module 405 is used to determine that the GCB of the generator is in a non-full-phase operation state if the negative sequence current corresponding to the generator terminal reaches a negative sequence current threshold.

[0084] Furthermore, the loop break judgment module 403 is also used to: pre-set the low-frequency phase voltage judgment standard, the first low-frequency open zero-sequence voltage judgment standard and the second low-frequency open zero-sequence voltage judgment standard corresponding to the monitoring data; judge whether the monitoring data meets the low-frequency phase voltage judgment standard; judge whether the monitoring data meets the first low-frequency open zero-sequence voltage judgment standard; judge whether the monitoring data meets the second low-frequency open zero-sequence voltage judgment standard. If it is determined that the monitoring data simultaneously meets the low-frequency phase voltage judgment standard, the first low-frequency open zero-sequence voltage judgment standard and the second low-frequency open zero-sequence voltage judgment standard, it is determined that a loop break has occurred in the generator.

[0085] Furthermore, the loop break judgment module 403 is also used to: for each phase, determine the corresponding first voltage threshold according to the corresponding first low-frequency phase voltage and the preset first amplitude coefficient; for each phase, obtain the difference between the corresponding first low-frequency phase voltage and the corresponding second low-frequency phase voltage; for each phase, judge whether the absolute value of the corresponding difference is greater than the corresponding first voltage threshold; if the absolute values ​​of the corresponding differences of the three phases are all greater than their respective corresponding first voltage thresholds, it is determined that the monitoring data meets the low-frequency phase voltage judgment standard.

[0086] Furthermore, the loop break judgment module 403 is also used to: determine the second voltage threshold based on the first low-frequency phase voltage, a preset second amplitude coefficient, and a preset multiple coefficient; compare the first low-frequency open zero-sequence voltage with the second voltage threshold, if the first low-frequency open zero-sequence voltage is less than the second voltage threshold, then determine that the monitoring data meets the first low-frequency open zero-sequence voltage judgment standard.

[0087] Furthermore, the loop break judgment module 403 is also used to: determine the third voltage threshold based on the second low-frequency phase voltage, a preset third amplitude coefficient, and a preset multiple coefficient; compare the second low-frequency open zero-sequence voltage with the third voltage threshold, if the second low-frequency open zero-sequence voltage is less than the third voltage threshold, then determine that the monitoring data meets the second low-frequency open zero-sequence voltage judgment standard.

[0088] Furthermore, the negative sequence current judgment module 404 is also used to: obtain the generator end phase current corresponding to the generator end, and extract the negative sequence current corresponding to the generator end based on the generator end phase current; preset a negative sequence current threshold value to determine whether the negative sequence current reaches the negative sequence current threshold value.

[0089] Furthermore, the data acquisition module 401 is further configured to: if it is determined that the position of the GCB has not changed, then continuously acquire the monitoring data corresponding to the generator.

[0090] In order to implement the above embodiment, the present application embodiment also proposes an electronic device 500, such as Figure 5 As shown, the electronic device 500 includes: a processor 501 and a memory 502 that is communicatively connected to the processor, the memory 502 stores instructions that can be executed by at least one processor, and the instructions are executed by at least one processor 501 to implement the detection method for non-full-phase operation of the generator end circuit breaker GCB as shown in the above embodiment.

[0091] In order to implement the above embodiment, the embodiment of the present application also proposes a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to enable the computer to implement the detection method of non-full-phase operation of the generator end circuit breaker GCB as shown in the above embodiment.

[0092] In order to implement the above embodiment, the embodiment of the present application also proposes a computer program product, including a computer program, which, when executed by a processor, implements the detection method for non-full-phase operation of the generator end circuit breaker GCB as shown in the above embodiment.

[0093] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0094] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0095] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for detecting non-full-phase operation of a generator end circuit breaker GCB, characterized in that: include: Acquire monitoring data corresponding to the generator during the grid connection process or the disconnection process, wherein the monitoring data includes a first low-frequency phase voltage and a first low-frequency open zero-sequence voltage corresponding to the generator end, and a second low-frequency phase voltage and a second low-frequency open zero-sequence voltage corresponding to the low-voltage side of the generator main transformer; Determine whether the position of the GCB has changed according to the closing position and the opening position of the GCB at the generator end; If it is determined that the position of the GCB changes, determine the start time of the position change of the GCB, and determine whether a primary circuit disconnection occurs in the generator according to the monitoring data within a preset time period starting from the start time; If it is determined that the primary circuit of the generator is disconnected, it is further determined whether the negative sequence current corresponding to the generator terminal reaches the negative sequence current threshold; If the negative sequence current corresponding to the generator terminal reaches the negative sequence current threshold, it is determined that the GCB of the generator is in a non-full-phase operation state.

2. The method according to claim 1, characterized in that: The determining, based on the monitoring data, whether a primary circuit of the generator is disconnected comprises: Pre-setting a low-frequency phase voltage judgment standard, a first low-frequency open zero-sequence voltage judgment standard and a second low-frequency open zero-sequence voltage judgment standard corresponding to the monitoring data; Determining whether the monitoring data meets the low-frequency phase voltage judgment standard; Determining whether the monitoring data meets the first low-frequency open zero-sequence voltage judgment standard; Determining whether the monitoring data meets the second low-frequency open zero-sequence voltage judgment standard; The determining that a primary circuit of the generator is disconnected comprises: If it is determined that the monitoring data simultaneously satisfies the low-frequency phase voltage judgment standard, the first low-frequency open zero-sequence voltage judgment standard and the second low-frequency open zero-sequence voltage judgment standard, it is determined that a primary circuit break occurs in the generator.

3. The method according to claim 2, characterized in that The determining whether the monitoring data meets the low-frequency phase voltage determination standard includes: For each phase, determining the corresponding first voltage threshold according to the corresponding first low-frequency phase voltage and a preset first amplitude coefficient; For each phase, obtaining a difference between the corresponding first low-frequency phase voltage and the corresponding second low-frequency phase voltage; For each phase, determining whether the absolute value of the corresponding difference is greater than the corresponding first voltage threshold; If the absolute values ​​of the differences corresponding to the three phases are all greater than their respective corresponding first voltage thresholds, it is determined that the monitoring data meets the low-frequency phase voltage judgment standard.

4. The method according to claim 3, characterized in that: The determining whether the monitoring data meets the first low-frequency open zero-sequence voltage determination standard includes: Determining a second voltage threshold according to the first low-frequency phase voltage, a preset second amplitude coefficient, and a preset multiple coefficient; The first low-frequency open zero-sequence voltage is compared with the second voltage threshold. If the first low-frequency open zero-sequence voltage is less than the second voltage threshold, it is determined that the monitoring data meets the first low-frequency open zero-sequence voltage judgment standard.

5. The method according to claim 4, characterized in that The determining whether the monitoring data meets the second low-frequency open zero-sequence voltage determination standard includes: Determining a third voltage threshold according to the second low-frequency phase voltage, a preset third amplitude coefficient, and a preset multiple coefficient; The second low-frequency open zero-sequence voltage is compared with the third voltage threshold. If the second low-frequency open zero-sequence voltage is less than the third voltage threshold, it is determined that the monitoring data meets the second low-frequency open zero-sequence voltage judgment standard.

6. The method according to claim 5, characterized in that The determining whether the negative sequence current corresponding to the generator terminal reaches the negative sequence current threshold comprises: Acquire a generator end phase current corresponding to the generator end, and extract a negative sequence current corresponding to the generator end based on the generator end phase current; A negative sequence current threshold is preset to determine whether the negative sequence current reaches the negative sequence current threshold.

7. The method according to claim 6, characterized in that After judging whether the position of the GCB has changed according to the closing position and the opening position of the GCB at the generator end, the method further includes: If it is determined that the position of the GCB has not changed, the monitoring data corresponding to the generator is continuously acquired.

8. A detection device for non-full-phase operation of a generator end circuit breaker GCB, characterized in that: include: A data acquisition module is used to acquire monitoring data corresponding to the generator during the grid connection process or the disconnection process, wherein the monitoring data includes a first low-frequency phase voltage and a first low-frequency open zero-sequence voltage corresponding to the generator end, and a second low-frequency phase voltage and a second low-frequency open zero-sequence voltage corresponding to the low-voltage side of the generator main transformer; A position determination module, used to determine whether a position change occurs to a GCB according to a closing position and an opening position of a GCB at a generator end; A loop disconnection judgment module is used to determine the start time of the GCB position change if it is determined that the GCB position change occurs, and to judge whether the generator has a loop disconnection according to the monitoring data within a preset time period starting from the start time; A negative sequence current judgment module is used to further judge whether the negative sequence current corresponding to the generator terminal reaches a negative sequence current threshold if it is judged that the primary circuit of the generator is disconnected; The state determination module is used to determine that the GCB of the generator is in a non-full-phase operation state if the negative sequence current corresponding to the generator terminal reaches a negative sequence current threshold.

9. An electronic device, comprising: at least one processor; as well as a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium storing computer instructions, wherein: The computer instructions are used to cause the computer to execute the method according to any one of claims 1-7.

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