Method and device for diagnosing fault of bus loop in hot bus switching operation

Abstract

The embodiment of the invention discloses a bus loop fault diagnosis method and device for hot bus switching operation. The method comprises the following steps: according to a bus topological graph of a to-be-detected transformer substation, determining buscouple interval information, inverted bus interval information, outgoing line interval information of each outgoing line interval, characteristic parameters of the to-be-detected transformer substation, a connection relationship between each outgoing line interval and the first bus and the second bus, and a position relationship between each outgoing line interval and the buscouple interval and the inverted bus interval; determining a target bus coupler three-phase current according to the bus coupler interval information, the inverted bus interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the to-be-detected transformer substation, the connection relationship between each outgoing line interval and the first bus and the second bus, and the position relationship between each outgoing line interval and the bus coupler interval and the inverted bus interval; and determining a bus loop state according to the target bus coupler three-phase current and the bus coupler interval information. According to the scheme, the bus loop state can be accurately judged, and the poor contact condition of the bus loop can be found in time.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of substations, and in particular to a method and device for diagnosing bus circuit faults in hot-reversal operation. Background Art

[0002] Single-phase or two-phase poor contact defects often occur in the conductive circuit of the busbar, especially the poor contact defects at the internal connections of the gas insulated metal-enclosed switchgear (GIS) busbar. These defects are still difficult to detect through routine infrared detection and other live detection methods, resulting in frequent sudden failures of the GIS internal busbar in recent years.

[0003] However, defects such as poor contact can be discovered in time through electrical quantities such as current and power, but in daily operation, the busbar conductive circuit has only one path for current, and the abnormal increase in the contact resistance of the conductive circuit cannot be reflected by the current magnitude, and thus the operating status of the busbar conductive circuit cannot be confirmed. Summary of the invention

[0004] The embodiment of the present invention provides a method and device for diagnosing bus circuit faults in a hot bus reverse operation, so as to accurately determine the state of the bus circuit and promptly discover the poor contact of the bus circuit.

[0005] In a first aspect, an embodiment of the present invention provides a method for diagnosing a bus circuit fault in a hot-reversed operation, the method comprising:

[0006] According to the busbar topology diagram of the substation to be detected, determine the busbar interval information, the reverse busbar interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be detected, the connection relationship between each of the outgoing line intervals and the first busbar and the second busbar, and the position relationship between each of the outgoing line intervals and the busbar interval and the reverse busbar interval;

[0007] Determine the target bus-tie three-phase current according to the bus-tie interval information, the reverse bus-tie interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be detected, the connection relationship between each outgoing line interval and the first bus and the second bus, and the position relationship between each outgoing line interval and the bus-tie interval and the reverse bus interval;

[0008] The bus loop state is determined according to the target bus-couple three-phase current and the bus-couple interval information.

[0009] Optionally, the step of determining the target bus-tie three-phase current includes:

[0010] Calculating the three-phase current of the inverted bus interval according to the inverted bus interval information;

[0011] Calculating the three-phase current of each outgoing line interval according to the outgoing line interval information of each outgoing line interval;

[0012] According to the positional relationship between each of the outgoing line intervals and the bus-tie interval and the reverse bus interval, the connection relationship between each of the outgoing line intervals and the first bus and the second bus, and the three-phase current of the outgoing line interval of each of the outgoing line intervals, determine the first three-phase total current of the outgoing line interval located on the side of the bus-tie interval away from the reverse bus interval running on the first bus, the second three-phase total current of the outgoing line interval located on the side of the reverse bus interval away from the bus-tie interval running on the first bus and the third three-phase total current of the outgoing line interval running on the second bus, the fourth three-phase total current of the outgoing line interval located between the reverse bus interval and the bus-tie interval running on the first bus and the fifth three-phase total current of the outgoing line interval running on the second bus, the first three-phase weighted current between the bus-tie interval and the reverse bus interval on the first bus, and the second three-phase weighted current between the bus-tie interval and the reverse bus interval on the second bus;

[0013] The target bus three-phase current is calculated based on the first three-phase total current, the second three-phase total current, the third three-phase total current, the fourth three-phase total current, the fifth three-phase total current, the first three-phase weighted current, the second three-phase weighted current, the characteristic parameters of the substation to be detected, and the reverse bus interval three-phase current.

[0014] Optionally, the reverse bus interval information includes reverse bus three-phase current value, reverse bus active power and reverse bus reactive power;

[0015] The step of calculating the three-phase current of the reverse bus interval includes:

[0016] Determine the inverted bus phase A of the inverted bus interval phase A current relative to the A phase bus voltage according to the inverted bus active power and the inverted bus reactive power;

[0017] According to the phase of the inverted mother phase A, determining the phase of the inverted mother phase B and the phase of the inverted mother phase C;

[0018] The inverted bus interval three-phase current is calculated according to the inverted bus three-phase current value, the inverted bus A phase, the inverted bus B phase and the inverted bus C phase.

[0019] Optionally, the outgoing line interval information includes outgoing line three-phase current value, outgoing line active power and outgoing line reactive power;

[0020] The step of calculating the three-phase current of each outgoing line interval comprises:

[0021] Determine the outgoing line A phase of the A phase current of each outgoing line interval relative to the A phase bus voltage according to the outgoing line active power and the outgoing line reactive power of each outgoing line interval;

[0022] According to the phase of the outgoing line A phase of each of the outgoing line intervals, determining the phase of the outgoing line B phase and the phase of the outgoing line C phase of each of the outgoing line intervals;

[0023] The three-phase current of each of the outgoing line intervals is calculated according to the three-phase current value of each of the outgoing line intervals, the phase of the outgoing line A phase, the phase of the outgoing line B phase, and the phase of the outgoing line C phase.

[0024] Optionally, the first three-phase total current includes a first A-phase total current, a first B-phase total current and a first C-phase total current;

[0025] The second three-phase total current includes a second A-phase total current, a second B-phase total current and a second C-phase total current;

[0026] The third three-phase total current includes a third A-phase total current, a third B-phase total current and a third C-phase total current;

[0027] The fourth three-phase total current includes a fourth A-phase total current, a fourth B-phase total current and a fourth C-phase total current;

[0028] The fifth three-phase total current includes the fifth A-phase total current, the fifth B-phase total current and the fifth C-phase total current;

[0029] The first three-phase weighted current includes a first A-phase weighted current, a first B-phase weighted current and a first C-phase weighted current;

[0030] The second three-phase weighted current includes a second A-phase weighted current, a second B-phase weighted current and a second C-phase weighted current;

[0031] The three-phase current of the inverted bus interval includes the A-phase current of the inverted bus interval, the B-phase current of the inverted bus interval and the C-phase current of the inverted bus interval;

[0032] The target bus-couple three-phase current includes a target bus-couple A phase current, a target bus-couple B phase current and a target bus-couple C phase current.

[0033] Optionally, the step of calculating the target bus-tie three-phase current includes:

[0034] Calculate the target bus-tie A-phase current according to the first A-phase total current, the second A-phase total current, the third A-phase total current, the fourth A-phase total current, the fifth A-phase total current, the first A-phase weighted current, the second A-phase weighted current, the characteristic parameter of the substation to be detected, and the inverted bus bay A-phase current;

[0035] Calculate the target bus-tie B-phase current according to the first B-phase total current, the second B-phase total current, the third B-phase total current, the fourth B-phase total current, the fifth B-phase total current, the first B-phase weighted current, the second B-phase weighted current, the characteristic parameter of the substation to be detected, and the inverted bus bay B-phase current;

[0036] The target bus-tie C-phase current is calculated based on the first C-phase total current, the second C-phase total current, the third C-phase total current, the fourth C-phase total current, the fifth C-phase total current, the first C-phase weighted current, the second C-phase weighted current, the characteristic parameters of the substation to be detected, and the inverse bus-interval C-phase current.

[0037] Optionally, the substation characteristic parameters to be detected include the impedance of the busbar section between adjacent bays, the impedance of the disconnector and the impedance of the bus tie circuit breaker;

[0038] The target busbar A phase current I A for:

[0039]

[0040] Wherein, N is the number of the outgoing line intervals between the reverse bus interval and the bus coupling interval, I 1A is the total current of the first phase A, I 4A is the total current of the fourth phase A, I 2A is the total current of the second phase A, I DA is the A-phase current of the inverted bus bay, I 3A is the total current of the third phase A, I 5A is the total current of the fifth phase A, N 1A is the first A-phase weighted current, N 2A is the second phase A weighted current, Z L is the impedance of the busbar section between the adjacent bays, Z D is the isolating switch impedance, Z S is the bus tie circuit breaker impedance;

[0041] The target busbar B phase current I B for:

[0042]

[0043] Wherein, N is the number of the outgoing line intervals between the reverse bus interval and the bus coupling interval, I 1B is the total current of the first phase B, I 4B is the total current of the fourth B phase, I 2B is the total current of the second phase B, IDB is the phase B current of the inverted bus bay, I 3B is the total current of the third phase B, I 5B is the total current of the fifth phase B, N 1B is the first B-phase weighted current, N 2B is the second B-phase weighted current;

[0044] The target busbar C phase current I C for:

[0045]

[0046] Wherein, N is the number of the outgoing line intervals between the reverse bus interval and the bus coupling interval, I 1C is the total current of the first phase C, I 4C is the total current of the fourth phase C, I 2C is the total current of the second phase C, I DC is the C-phase current of the inverted bus bay, I 3C is the total current of the third phase C, I 5C is the total current of the fifth phase C, N 1C is the first C phase weighted current, N 2C is the second C-phase weighted current.

[0047] Optionally, the bus coupling interval information also includes actual bus coupling three-phase current value;

[0048] The bus circuit state includes a fault state and a normal state;

[0049] The determining of the bus circuit state comprises:

[0050] Calculate the bus coupling A phase current ratio, the bus coupling B phase current ratio and the bus coupling C phase current ratio according to the actual bus coupling three-phase current value and the target bus coupling three-phase current;

[0051] Calculate the imbalance of the bus coupling three-phase current ratio according to the bus coupling A phase current ratio, the bus coupling B phase current ratio and the bus coupling C phase current ratio;

[0052] If the unbalance degree of the busbar three-phase current ratio is greater than the unbalance degree threshold, the busbar loop state is a fault state;

[0053] If the unbalance degree of the busbar three-phase current ratio is less than or equal to the unbalance degree threshold, the busbar loop state is normal.

[0054] Optionally, the step of calculating the unbalance degree of the bus-connecting three-phase current ratio includes:

[0055] Determine a maximum phase current ratio and a minimum phase current ratio among the bus coupling A phase current ratio, the bus coupling B phase current ratio, and the bus coupling C phase current ratio;

[0056] The unbalance degree of the bus-connecting three-phase current ratio is calculated according to the maximum phase current ratio and the minimum phase current ratio.

[0057] In a second aspect, an embodiment of the present invention further provides a bus circuit fault diagnosis device for hot reverse bus operation, the hot reverse bus circuit fault diagnosis device comprising:

[0058] An acquisition module is used to determine the busbar interval information, the reverse busbar interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be detected, the connection relationship between each outgoing line interval and the first busbar and the second busbar, and the position relationship between each outgoing line interval and the busbar interval and the reverse busbar interval according to the busbar topology diagram of the substation to be detected;

[0059] A target bus-tie three-phase current determination module, configured to determine the target bus-tie three-phase current according to the bus-tie interval information, the reverse bus interval information, the outgoing line interval information of each of the outgoing line intervals, the characteristic parameters of the substation to be detected, the connection relationship between each of the outgoing line intervals and the first bus and the second bus, and the positional relationship between each of the outgoing line intervals and the bus-tie intervals and the reverse bus intervals;

[0060] The bus circuit state determination module is used to determine the bus circuit state according to the target bus three-phase current and the bus interval information.

[0061] The embodiment of the present invention determines the bus coupling interval information, the reverse bus interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be detected, the connection relationship between each outgoing line interval and the first bus and the second bus, and the position relationship between each outgoing line interval and the bus coupling interval and the reverse bus interval according to the bus topology diagram of the substation to be detected; thereby, according to the bus coupling interval information, the reverse bus interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be detected, the connection relationship between each outgoing line interval and the first bus and the second bus, and the position relationship between each outgoing line interval and the bus coupling interval and the reverse bus interval, the ideal bus coupling three-phase current of the bus loop in the absence of faults (under ideal working conditions without poor contact) - the target bus coupling three-phase current; and then according to the target bus coupling three-phase current and the bus coupling interval information, the difference between the target bus coupling three-phase current and the actual bus coupling three-phase current included in the bus coupling interval information can be judged, and it can be judged whether the internal flow of the bus loop has undergone a three-phase unbalanced change, so as to accurately determine the state of the bus loop. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0063] Figure 1 A schematic flow chart of a method for diagnosing a bus circuit fault in a hot bus reverse operation provided by an embodiment of the present invention;

[0064] Figure 2 A schematic diagram of a flow chart of steps for determining a target bus-tie three-phase current provided by an embodiment of the present invention;

[0065] Figure 3 A schematic flow chart of the steps of calculating the three-phase current of the reverse bus interval provided by an embodiment of the present invention;

[0066] Figure 4 A schematic flow chart of a step of calculating the three-phase current of each outgoing line interval provided by an embodiment of the present invention;

[0067] Figure 5 A schematic flow chart of a step of determining a bus circuit state provided by an embodiment of the present invention;

[0068] Figure 6 A schematic flow chart of the steps of calculating the unbalance degree of the bus-connection three-phase current ratio provided by an embodiment of the present invention;

[0069] Figure 7 A schematic structural diagram of a bus circuit fault diagnosis device for hot bus reverse operation provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0070] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0071] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0072] In daily operation, the busbar conductive circuit has only one path for the current on the busbar, and the abnormal increase in the contact resistance of the conductive circuit cannot be reflected by the current size, and thus the operating status of the busbar conductive circuit cannot be confirmed. However, during the hot bus reverse operation, the first busbar and the second busbar can form a closed loop through the busbar side disconnector of the bus reverse interval, the circuit breaker of the bus tie interval, and the busbar side disconnector of the bus tie interval. If there is a poor contact defect in the busbar circuit, the current inside the busbar constituting the closed loop will change to a three-phase unbalanced change, and the current amplitude of the poor contact phase will deviate from the normal phase, causing an imbalance in the three-phase current of the bus tie circuit breaker. In this regard, this scheme proposes a hot bus reverse operation busbar circuit fault diagnosis method, which can use the short-term closed loop current redistribution that occurs in the hot bus reverse operation to diagnose the busbar circuit status and promptly detect poor contact in the busbar circuit.

[0073] Figure 1 The present invention provides a flow chart of a method for diagnosing a bus circuit fault during a hot bus operation. This embodiment is applicable to monitoring the operation of a bus circuit during a hot bus operation. The method can be implemented by a hot bus operation bus circuit fault diagnosis device. The method specifically includes the following steps:

[0074] S110. According to the busbar topology diagram of the substation to be tested, determine the busbar coupling interval information, the reverse busbar interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be tested, the connection relationship between each outgoing line interval and the first busbar and the second busbar, and the positional relationship between each outgoing line interval and the busbar coupling interval and the reverse busbar interval.

[0075] Specifically, the busbar topology diagram of the substation to be detected is constructed in advance according to the actual distribution of the substation to be detected. The busbar interval refers to the interval equipment area connecting two sections of the busbar in the power system. The busbar interval information is the operating information of the interval equipment connecting the two sections of the busbar (such as current value and power, etc.). During the hot busbar reversal operation, the disconnectors on the busbar side of the busbar interval are all in a closed state to achieve simultaneous connection with the two busbars. The busbar reversal interval refers to the interval equipment area involved in the busbar reversal operation of the power system. The busbar reversal interval information is the operating information of the interval equipment involved in the busbar operation (such as current value and power, etc.). During the hot busbar reversal operation, the busbar side disconnectors of the busbar reversal interval need to be in a closed state to achieve simultaneous connection with the two busbars. The outgoing line interval refers to the important interval area connecting the substation and the external line in the power system. The outgoing line interval information refers to the operating information of the equipment in the important interval area connected to the external line (such as current value and power, etc.). During the hot busbar reversal operation, each outgoing line interval is connected to a busbar. The substation characteristic parameters to be tested refer to fixed specific parameters of the substation fixed equipment, such as the impedance of the busbar section between adjacent bays, the impedance of the disconnector and the impedance of the bus tie circuit breaker.

[0076] S120. Determine the target bus-tie three-phase current based on the bus-tie interval information, the reverse bus-tie interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be detected, the connection relationship between each outgoing line interval and the first bus and the second bus, and the positional relationship between each outgoing line interval and the bus-tie interval and the reverse bus interval.

[0077] Specifically, the busbar three-phase current refers to the three-phase current in the busbar interval passing through the busbar circuit breaker and other equipment. The target busbar three-phase current is the ideal three-phase current of the busbar circuit breaker when the busbar circuit is fault-free (under ideal working conditions without poor contact).

[0078] Among them, during the hot bus-reversing operation, it is necessary to close the disconnected isolating switch on the bus side of the bus-reversing interval. At this time, there will be a problem of failure to close the isolating switch on the bus side of the bus-reversing interval, which will cause poor contact in the bus circuit and cause the bus circuit to fail.

[0079] In this regard, the present scheme can determine the ideal bus-binding three-phase current, i.e., the target bus-binding three-phase current, of the bus circuit in the absence of faults (under ideal working conditions without poor contact) based on real-time data such as bus-binding interval information, reverse bus-binding interval information, outgoing line interval information of each outgoing line interval, characteristic parameters of the substation to be detected, the connection relationship between each outgoing line interval and the first bus and the second bus, and the position relationship between each outgoing line interval and the bus-binding interval and the reverse bus-binding interval.

[0080] S130. Determine the bus loop state according to the target bus three-phase current and bus interval information.

[0081] Among them, if the busbar circuit has a poor contact defect (the busbar circuit is in an abnormal state), the internal flow of the busbar constituting the closed loop will undergo a three-phase unbalanced change, and the current amplitude of the poor contact phase will deviate from the current amplitude of the normal phase, thereby causing a three-phase imbalance in the ratio of the target busbar current and the actual busbar current included in the busbar interval information; if the busbar circuit does not have a poor contact defect (the busbar circuit is in a normal state), the internal flow of the busbar constituting the closed loop will not undergo a three-phase unbalanced change, and will not cause a three-phase imbalance in the ratio of the target busbar current and the actual busbar current.

[0082] In addition, the bus tie interval information includes the actual bus tie three-phase current of the bus tie circuit breaker. Therefore, according to the target bus tie three-phase current and the actual bus tie three-phase current, it can be judged whether the internal flow of the bus loop has a three-phase unbalance change, and then the bus loop state can be determined.

[0083] The embodiment of the present invention determines the bus coupling interval information, the reverse bus interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be detected, the connection relationship between each outgoing line interval and the first bus and the second bus, and the position relationship between each outgoing line interval and the bus coupling interval and the reverse bus interval according to the bus topology diagram of the substation to be detected; thereby, according to the bus coupling interval information, the reverse bus interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be detected, the connection relationship between each outgoing line interval and the first bus and the second bus, and the position relationship between each outgoing line interval and the bus coupling interval and the reverse bus interval, the ideal bus coupling three-phase current of the bus loop in the absence of faults (under ideal working conditions without poor contact) - the target bus coupling three-phase current; and then according to the target bus coupling three-phase current and the bus coupling interval information, the difference between the target bus coupling three-phase current and the actual bus coupling three-phase current included in the bus coupling interval information can be judged, and it can be judged whether the internal flow of the bus loop has undergone a three-phase unbalanced change, so as to accurately determine the state of the bus loop.

[0084] Based on the above embodiment, optionally, Figure 2 A schematic flow chart of a step of determining a target bus-couple three-phase current provided by an embodiment of the present invention. Figure 2 As shown in the figure, the steps for determining the target bus-connection three-phase current are described:

[0085] S210. Calculate the three-phase current of the reverse bus interval according to the reverse bus interval information.

[0086] Among them, the reverse bus interval information includes the reverse bus three-phase current value, reverse bus active power and reverse bus reactive power. The three-phase current of the reverse bus interval is a vector. Since the phase of each phase of the reverse bus three-phase current cannot be directly obtained from the background monitoring machine, the reverse bus active power and reverse bus reactive power of the reverse bus interval can be used to calculate the power factor angle of the three-phase current of the reverse bus interval, and use the A-phase bus voltage as a reference to calculate the phase of the reverse bus A-phase current relative to the A-phase bus voltage - reverse bus A phase. The phases of the reverse bus B-phase and C-phase currents can be calculated based on the phase of the A-phase current of the reverse bus interval, and then the three-phase current of the reverse bus interval is calculated through the reverse bus three-phase current value and the reverse bus three-phase current phase.

[0087] S220. Calculate the three-phase current of each outgoing line interval according to the outgoing line interval information of each outgoing line interval.

[0088] Among them, the outgoing line interval information of each outgoing line interval includes the outgoing line three-phase current value, the outgoing line active power and the outgoing line reactive power. The outgoing line interval three-phase current is a vector. Since the phase of each phase of the three-phase current of the outgoing line interval cannot be detected, the outgoing line active power and the outgoing line reactive power of the outgoing line interval can be used to calculate the power factor angle of the three-phase current of the outgoing line interval, and the phase of the outgoing line A phase current relative to the A phase bus voltage is calculated with the A phase bus voltage as a reference-outgoing line A phase. The phase of the outgoing line B phase and the phase of the C phase current can be obtained according to the outgoing line A phase calculation. The outgoing line interval three-phase current is calculated by the outgoing line three-phase current value and the outgoing line three-phase current phase (the phase of the outgoing line A phase, the outgoing line B phase and the C phase current) of each outgoing line interval.

[0089] S230. According to the positional relationship between each outgoing line interval and the bus-tie interval and the reverse bus interval, the connection relationship between each outgoing line interval and the first bus and the second bus, and the three-phase current of each outgoing line interval, determine the first three-phase total current of the outgoing line interval located on the side of the bus-tie interval away from the reverse bus interval running on the first bus, the second three-phase total current of the outgoing line interval located on the side of the reverse bus interval away from the bus-tie interval running on the first bus and the third three-phase total current of the outgoing line interval running on the second bus, the fourth three-phase total current of the outgoing line interval located between the reverse bus interval and the bus-tie interval running on the first bus and the fifth three-phase total current of the outgoing line interval running on the second bus, the first three-phase weighted current between the bus-tie interval and the reverse bus interval on the first bus, and the second three-phase weighted current between the bus-tie interval and the reverse bus interval on the second bus.

[0090] Among them, the specific position of each outgoing line interval relative to the bus-coupling interval and the inverted bus interval can be known according to the positional relationship between each outgoing line interval and the bus-coupling interval and the inverted bus interval. The bus connected to each underlined interval can be known according to the connection relationship between each outgoing line interval and the first bus and the second bus. The first three-phase total current is the sum of the currents of the outgoing line intervals connected to the first bus on the side of the bus-coupling interval away from the inverted bus interval. The second three-phase total current is the sum of the currents of the outgoing line intervals connected to the first bus on the side of the inverted bus interval away from the bus-coupling interval. The third three-phase total current is the sum of the currents of the outgoing line intervals connected to the second bus on the side of the inverted bus interval away from the bus-coupling interval. The fourth three-phase total current is the sum of the currents of the outgoing line intervals connected to the first bus between the inverted bus interval and the bus-coupling interval. The fifth three-phase total current is the sum of the currents of the outgoing line intervals connected to the second bus between the inverted bus interval and the bus-coupling interval.

[0091] In addition, the first three-phase total current includes the first A-phase total current, the first B-phase total current and the first C-phase total current; the second three-phase total current includes the second A-phase total current, the second B-phase total current and the second C-phase total current; the third three-phase total current includes the third A-phase total current, the third B-phase total current and the third C-phase total current; the fourth three-phase total current includes the fourth A-phase total current, the fourth B-phase total current and the fourth C-phase total current; the fifth three-phase total current includes the fifth A-phase total current, the fifth B-phase total current and the fifth C-phase total current.

[0092] Specifically, the first A-phase total current is the sum of the A-phase currents of the outgoing line intervals connected to the first busbar on the side of the bus-coupled interval away from the reverse bus interval; the first B-phase total current is the sum of the B-phase currents of the outgoing line intervals connected to the first busbar on the side of the bus-coupled interval away from the reverse bus interval; the first C-phase total current is the sum of the C-phase currents of the outgoing line intervals connected to the first busbar on the side of the bus-coupled interval away from the reverse bus interval. The second A-phase total current is the sum of the A-phase currents of the outgoing line intervals connected to the first busbar on the side of the reverse bus interval away from the bus-coupled interval; the second B-phase total current is the sum of the B-phase currents of the outgoing line intervals connected to the first busbar on the side of the reverse bus interval away from the bus-coupled interval; the second C-phase total current is the sum of the C-phase currents of the outgoing line intervals connected to the first busbar on the side of the reverse bus interval away from the bus-coupled interval. The third A-phase total current is the sum of the A-phase currents of the outgoing line intervals connected to the second busbar on the side of the reverse bus interval away from the bus-coupling interval; the third B-phase total current is the sum of the B-phase currents of the outgoing line intervals connected to the second busbar on the side of the reverse bus interval away from the bus-coupling interval; the third C-phase total current is the sum of the C-phase currents of the outgoing line intervals connected to the second busbar on the side of the reverse bus interval away from the bus-coupling interval. The fourth A-phase total current is the sum of the A-phase currents of the outgoing line intervals connected to the first busbar between the reverse bus interval and the bus-coupling interval; the fourth B-phase total current is the sum of the B-phase currents of the outgoing line intervals connected to the first busbar between the reverse bus interval and the bus-coupling interval; the fourth C-phase total current is the sum of the C-phase currents of the outgoing line intervals connected to the first busbar between the reverse bus interval and the bus-coupling interval. The fifth A-phase total current is the sum of the A-phase currents of the outgoing line intervals connected to the second bus between the inverted bus interval and the bus-binding interval; the fifth B-phase total current is the sum of the B-phase currents of the outgoing line intervals connected to the second bus between the inverted bus interval and the bus-binding interval; the fifth C-phase total current is the sum of the C-phase currents of the outgoing line intervals connected to the second bus between the inverted bus interval and the bus-binding interval.

[0093] The first three-phase weighted current is: Among them, I i Indicates the current value of the ith outgoing line bay from the busbar bay to the reverse busbar bay. If the ith outgoing line bay runs on the second busbar, then I i =0, if running on the first bus, then I i It is the three-phase current of the outgoing line interval.

[0094] The second three-phase weighted current is: Among them, I i It indicates the current value of the ith outgoing line bay from the busbar bay to the reverse busbar bay. If the ith outgoing line bay runs on the first busbar, then I i =0, if running on the second bus, then I i It is the three-phase current of the outgoing line interval.

[0095] Wherein, the first three-phase weighted current includes a first A-phase weighted current, a first B-phase weighted current and a first C-phase weighted current;

[0096] The first phase A weighted current is: Among them, I iA Indicates the A-phase current value of the ith outgoing line from the busbar to the reverse busbar. If the ith outgoing line bay runs on the second busbar, I iA =0, if running on the first bus, then I iA is the outgoing A phase current.

[0097] The first B-phase weighted current is: Among them, I iB Indicates the B-phase current value of the ith outgoing line from the busbar to the reverse busbar. If the ith outgoing line bay runs on the second busbar, I iB =0, if running on the first bus, then I iB is the outgoing B phase current.

[0098] The first C phase weighted current is: Among them, I iC Indicates the C-phase current value of the ith outgoing line from the busbar to the reverse busbar. If the ith outgoing line bay runs on the second busbar, I iC =0, if running on the first bus, then I iC is the outgoing C phase current.

[0099] The second three-phase weighted current includes a second A-phase weighted current, a second B-phase weighted current, and a second C-phase weighted current.

[0100] The second phase A weighted current is: Among them, I iA Indicates the A-phase current value of the ith outgoing line from the busbar to the reverse busbar. If the ith outgoing line bay runs on the first busbar, I iA =0, if running on the second bus, then I iA is the outgoing A phase current.

[0101] The second B phase weighted current is: Among them, I iB Indicates the B-phase current value of the ith outgoing line from the busbar to the reverse busbar. If the ith outgoing line bay runs on the first busbar, I iB =0, if running on the second bus, then I iB is the outgoing B phase current.

[0102] The second C phase weighted current is: Among them, I iC Indicates the C-phase current value of the ith outgoing line from the busbar to the reverse busbar. If the ith outgoing line bay runs on the first busbar, then I iC =0, if running on the second bus, then I iC is the outgoing C phase current.

[0103] S240. Calculate the target bus-tie three-phase current according to the first three-phase total current, the second three-phase total current, the third three-phase total current, the fourth three-phase total current, the fifth three-phase total current, the first three-phase weighted current, the second three-phase weighted current, the characteristic parameters of the substation to be detected, and the three-phase current of the reverse bus interval.

[0104] The characteristic parameters of the substation to be tested include the impedance of the busbar section between adjacent bays, the impedance of the disconnector and the impedance of the bus tie circuit breaker;

[0105] The target busbar three-phase current I0 is:

[0106]

[0107] Where N is the number of outgoing line bays between the reverse bus bay and the bus coupling bay, I1 is the total current of the first three phases, I4 is the total current of the fourth three phases, I2 is the total current of the second three phases, and I D is the three-phase current of the inverted busbar, I3 is the total current of the third three-phase, I5 is the total current of the fifth three-phase, N1 is the weighted current of the first three-phase, N2 is the weighted current of the second three-phase, Z L is the impedance of the busbar section between adjacent bays, Z D is the isolating switch impedance, Z S Specifically, the reverse bus interval three-phase current includes the reverse bus interval A phase current, the reverse bus interval B phase current and the reverse bus interval C phase current; the target bus three-phase current includes the target bus A phase current, the target bus B phase current and the target bus C phase current.

[0108] Among them, the target bus A-phase current is calculated based on the total current of the first A-phase, the total current of the second A-phase, the total current of the third A-phase, the total current of the fourth A-phase, the total current of the fifth A-phase, the weighted current of the first A-phase, the weighted current of the second A-phase, the characteristic parameters of the substation to be tested, and the A-phase current of the inverted bus interval.

[0109] Target busbar three-phase current I A for:

[0110]

[0111] Where N is the number of outgoing line bays between the reverse bus bay and the bus coupling bay, I 1A is the total current of the first phase A, I 4A is the total current of the fourth phase A, I 2A is the total current of the second phase A, I DA is the A phase current of the inverted busbar, I 3A is the total current of the third phase A, I 5A is the total current of the fifth phase A, N 1Ais the first phase A weighted current, N 2A is the second A phase weighted current.

[0112] Calculate the target bus-bundle B-phase current based on the first B-phase total current, the second B-phase total current, the third B-phase total current, the fourth B-phase total current, the fifth B-phase total current, the first B-phase weighted current, the second B-phase weighted current, the characteristic parameters of the substation to be tested, and the inverted bus-bundle B-phase current.

[0113] Target busbar B phase current I B for:

[0114]

[0115] Where N is the number of outgoing line bays between the reverse bus bay and the bus coupling bay, I 1B is the total current of the first phase B, I 4B is the total current of the fourth phase B, I 2B is the total current of the second phase B, I DB is the phase B current of the inverted busbar, I 3B is the total current of the third phase B, I 5B is the total current of the fifth phase B, N 1B is the first B phase weighted current, N 2B is the second B-phase weighted current.

[0116] Calculate the target bus-tie C-phase current based on the first C-phase total current, the second C-phase total current, the third C-phase total current, the fourth C-phase total current, the fifth C-phase total current, the first C-phase weighted current, the second C-phase weighted current, the characteristic parameters of the substation to be tested, and the inverse bus-interval C-phase current.

[0117] Target busbar C phase current I C for:

[0118]

[0119] Where N is the number of outgoing line bays between the reverse bus bay and the bus coupling bay, I 1C is the total current of the first phase C, I 4C is the total current of the fourth phase C, I 2C is the total current of the second phase C, I DC is the C phase current of the inverted bus bay, I 3C is the total current of the third phase C, I 5C is the total current of the fifth phase C, N 1C is the first C phase weighted current, N 2C is the second C phase weighted current.

[0120] Based on the above embodiment, optionally, Figure 3A flowchart of the steps for calculating the three-phase current of the reverse bus interval provided by an embodiment of the present invention. Figure 3 As shown in the figure, the steps for calculating the three-phase current of the reverse bus bay are explained:

[0121] S310. Determine the reverse bus A phase of the reverse bus interval A phase current relative to the A phase bus voltage according to the reverse bus active power and the reverse bus reactive power.

[0122] Specifically, the inverted mother A phase Among them, Q1 is the reverse mother reactive power, and P1 is the reverse mother active power.

[0123] S320. Determine the phases of the inverted mother phase B and the inverted mother phase C according to the phase of the inverted mother phase A.

[0124] Among them, the phase difference between the inverted mother B phase and the inverted mother A phase is 120°, and the phase difference between the inverted mother C phase and the inverted mother A phase is 120°. Inverted mother C phase

[0125] S330. Calculate the inverted bus interval three-phase current according to the inverted bus three-phase current value, the inverted bus A phase, the inverted bus B phase and the inverted bus C phase.

[0126] Among them, the reverse bus three-phase current value includes the reverse bus A phase current value, the reverse bus B phase current value and the reverse bus C phase current value; the reverse bus interval three-phase current includes the reverse bus interval A phase current, the reverse bus interval B phase current and the reverse bus interval C phase current;

[0127] Therefore, the inverted bus interval A phase current can be determined according to the inverted bus A phase current value and the inverted bus A phase phase; the inverted bus interval B phase current can be determined according to the inverted bus B phase current value and the inverted bus B phase phase; the inverted bus interval C phase current can be determined according to the inverted bus C phase current value and the inverted bus C phase phase.

[0128] Based on the above embodiment, optionally, Figure 4 A flow chart of the steps of calculating the three-phase current of each outgoing line interval provided by an embodiment of the present invention. Figure 4 As shown in the figure, the steps for calculating the three-phase current of each outgoing line interval are explained:

[0129] S410. Determine the outgoing line A phase of the A phase current of each outgoing line interval relative to the A phase bus voltage according to the outgoing line active power and the outgoing line reactive power of each outgoing line interval.

[0130] Specifically, the phase of the outgoing line A phase Among them, Q2 is the outgoing reactive power, and P2 is the outgoing active power.

[0131] S420 , determining the phases of the outgoing line B phase and the outgoing line C phase of each outgoing line interval according to the phase of the outgoing line A phase of each outgoing line interval.

[0132] Among them, the phase difference between the phase of the outgoing line B and the phase of the outgoing line A is 120°, and the phase difference between the phase of the outgoing line C and the phase of the outgoing line A is 120°. Phase of outgoing line C

[0133] S430, calculating the three-phase current of each outgoing line interval according to the outgoing line three-phase current value of each outgoing line interval, the outgoing line A phase, the outgoing line B phase phase and the outgoing line C phase phase.

[0134] Among them, the outgoing three-phase current value includes the outgoing A-phase current value, the outgoing B-phase current value and the outgoing C-phase current value; the outgoing interval three-phase current includes the outgoing A-phase current, the outgoing B-phase current and the outgoing C-phase current.

[0135] Therefore, the outgoing line A phase current can be determined according to the outgoing line A phase current value and the outgoing line A phase phase; the outgoing line B phase current can be determined according to the outgoing line B phase current value and the outgoing line B phase phase; the outgoing line C phase current can be determined according to the outgoing line C phase current value and the outgoing line C phase phase.

[0136] On the basis of the above embodiment, optionally, the bus-tie interval information also includes actual bus-tie three-phase current value; the bus loop status includes a fault state and a normal state.

[0137] Among them, the actual bus-tie three-phase current refers to the three-phase current actually passing through the bus-tie circuit breaker and other equipment in the bus-tie interval. The actual bus-tie three-phase current includes the actual bus-tie A phase current value, the actual bus-tie B phase current value, and the actual bus-tie C phase current value. The target bus-tie three-phase current includes the target bus-tie A phase current, the target bus-tie B phase current, and the target bus-tie C phase current; the target bus-tie A phase current value can be obtained based on the target bus-tie B phase current, the target bus-tie B phase current value can be obtained based on the target bus-tie B phase current, and the target bus-tie C phase current value can be obtained based on the target bus-tie C phase current.

[0138] Figure 5 A flow chart of a step of determining a bus circuit state provided by an embodiment of the present invention is shown as follows: Figure 5 As shown in the figure, the steps for determining the bus circuit status are explained:

[0139] S510. Calculate the bus-tie A phase current ratio, the bus-tie B phase current ratio, and the bus-tie C phase current ratio according to the actual bus-tie three-phase current and the target bus-tie three-phase current.

[0140] Wherein, bus coupling A phase current ratio = actual bus coupling A phase current value / target bus coupling A phase current value;

[0141] Bus coupling B phase current ratio = actual bus coupling B phase current value / target bus coupling B phase current value;

[0142] Main coupling C phase current ratio = actual main coupling C phase current value / target main coupling C phase current value.

[0143] S520. Calculate the imbalance of the bus tie three-phase current ratio according to the bus tie A phase current ratio, the bus tie B phase current ratio and the bus tie C phase current ratio.

[0144] Specifically, based on the bus A phase current ratio, the bus B phase current ratio and the bus C phase current ratio, the maximum phase current ratio and the minimum phase current ratio among the three bus current ratios can be determined, so that the maximum difference between different phases can be obtained based on the maximum phase current ratio and the minimum phase current ratio, that is, the imbalance of the three-phase current ratio of the bus can be obtained.

[0145] S530, if the unbalance degree of the busbar three-phase current ratio is greater than the unbalance degree threshold, the busbar circuit state is a fault state;

[0146] S540: If the unbalance degree of the bus-connecting three-phase current ratio is less than or equal to the unbalance degree threshold, the bus circuit state is normal.

[0147] The imbalance threshold is a reference value preset according to actual conditions.

[0148] For example, assuming that the unbalance threshold is 85%, if the unbalance of the bus three-phase current ratio is greater than 85%, the bus loop state is a fault state; if the unbalance of the bus three-phase current ratio is less than or equal to 85%, the bus loop state is a normal state.

[0149] Based on the above embodiment, optionally, Figure 6 A flowchart of the steps for calculating the unbalance degree of the bus-connected three-phase current ratio provided by an embodiment of the present invention. Figure 6 As shown in the figure, the steps for calculating the unbalance degree of the busbar three-phase current ratio are explained:

[0150] S610. Determine the maximum phase current ratio and the minimum phase current ratio among the bus tie A phase current ratio, the bus tie B phase current ratio, and the bus tie C phase current ratio.

[0151] S620. Calculate the imbalance of the bus-connecting three-phase current ratio according to the maximum phase current ratio and the minimum phase current ratio.

[0152] Specifically, the unbalanced ratio of the three-phase current of the busbar

[0153] Among them, P A is the busbar A phase current ratio, PB is the busbar B phase current ratio and P C It is the current ratio of the main coupling C phase.

[0154] Figure 7 A schematic diagram of a bus circuit fault diagnosis device for hot reverse operation provided by an embodiment of the present invention is shown in FIG. Figure 7 As shown, the bus circuit fault diagnosis device for hot reverse bus operation includes:

[0155] The acquisition module 710 is used to determine the busbar interval information, the reverse busbar interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be detected, the connection relationship between each outgoing line interval and the first busbar and the second busbar, and the position relationship between each outgoing line interval and the busbar interval and the reverse busbar interval according to the busbar topology diagram of the substation to be detected;

[0156] The target bus-tie three-phase current determination module 720 is used to determine the target bus-tie three-phase current according to the bus-tie interval information, the reverse bus interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be detected, the connection relationship between each outgoing line interval and the first bus and the second bus, and the position relationship between each outgoing line interval and the bus-tie interval and the reverse bus interval;

[0157] The bus circuit state determination module 730 is used to determine the bus circuit state according to the target bus three-phase current and bus interval information.

[0158] In the embodiment of the present invention, the acquisition module 710 determines the busbar interval information, the reverse busbar interval information, the outgoing line interval information of each interval, the characteristic parameters of the substation to be detected, the connection relationship between each outgoing line interval and the first bus and the second bus, and the position relationship between each outgoing line interval and the busbar interval and the reverse busbar interval according to the busbar topology diagram of the substation to be detected; thus, the target busbar three-phase current determination module 720 determines the ideal busbar three-phase current of the bus circuit in the absence of faults (under ideal working conditions without poor contact) - the target busbar three-phase current according to the busbar interval information, the reverse busbar interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be detected, the connection relationship between each outgoing line interval and the first bus and the second bus, and the position relationship between each outgoing line interval and the busbar interval and the reverse busbar interval; and then the bus circuit state determination module 730 can determine the difference between the target busbar three-phase current and the actual busbar three-phase current included in the busbar interval information according to the target busbar three-phase current and the busbar interval information, and determine whether the flow change inside the bus circuit is three-phase balanced, so as to accurately determine the bus circuit state.

[0159] Based on the above embodiment, optionally, the target bus-tie three-phase current determination module includes:

[0160] A first calculation unit is used to calculate the three-phase current of the inverted bus bay according to the inverted bus bay information;

[0161] A second calculation unit is used to calculate the three-phase current of each outgoing line interval according to the outgoing line interval information of each outgoing line interval;

[0162] A third calculation unit is used to determine, according to the positional relationship between each outgoing line interval and the bus-coupling interval and the reverse bus interval, the connection relationship between each outgoing line interval and the first bus and the second bus, and the three-phase current of each outgoing line interval, a first three-phase total current running on the first bus of the outgoing line interval located on the side of the bus-coupling interval away from the reverse bus interval, a second three-phase total current running on the first bus and a third three-phase total current running on the second bus of the outgoing line interval located on the side of the reverse bus interval away from the bus-coupling interval, a fourth three-phase total current running on the first bus and a fifth three-phase total current running on the second bus of the outgoing line interval located between the reverse bus interval and the bus-coupling interval, a first three-phase weighted current between the bus-coupling interval and the reverse bus interval on the first bus, and a second three-phase weighted current between the bus-coupling interval and the reverse bus interval on the second bus;

[0163] The fourth calculation unit is used to calculate the target bus three-phase current based on the first three-phase total current, the second three-phase total current, the third three-phase total current, the fourth three-phase total current, the fifth three-phase total current, the first three-phase weighted current, the second three-phase weighted current, the characteristic parameters of the substation to be detected, and the three-phase current of the reverse bus interval.

[0164] On the basis of the above embodiment, optionally, the reverse bus interval information includes the reverse bus three-phase current value, the reverse bus active power and the reverse bus reactive power;

[0165] The first computing unit is specifically configured to:

[0166] Determine the inverted bus phase A of the inverted bus interval A phase current relative to the A phase bus voltage according to the inverted bus active power and the inverted bus reactive power;

[0167] According to the phase of the inverted mother phase A, the phases of the inverted mother phase B and the inverted mother phase C are determined;

[0168] The inverted bus interval three-phase current is calculated based on the inverted bus three-phase current value, the inverted bus A phase, the inverted bus B phase and the inverted bus C phase.

[0169] On the basis of the above embodiment, optionally, the outgoing line interval information includes outgoing line three-phase current value, outgoing line active power and outgoing line reactive power;

[0170] The second computing unit is specifically configured to:

[0171] According to the outgoing active power and the outgoing reactive power of each outgoing interval, the outgoing A phase of the A phase current of each outgoing interval relative to the A phase bus voltage is determined;

[0172] According to the phase of the outgoing line A phase of each outgoing line interval, the phase of the outgoing line B phase and the phase of the outgoing line C phase of each occurrence interval are determined;

[0173] The three-phase current of each outgoing line interval is calculated according to the three-phase current value of each outgoing line interval, the phase of the outgoing line A phase, the phase of the outgoing line B phase and the phase of the outgoing line C phase.

[0174] Based on the above embodiment, optionally,

[0175] The first three-phase total current includes the first A-phase total current, the first B-phase total current and the first C-phase total current;

[0176] The second three-phase total current includes the second A-phase total current, the second B-phase total current and the second C-phase total current;

[0177] The third three-phase total current includes the third A-phase total current, the third B-phase total current and the third C-phase total current;

[0178] The fourth three-phase total current includes the fourth A-phase total current, the fourth B-phase total current and the fourth C-phase total current;

[0179] The fifth three-phase total current includes the fifth A-phase total current, the fifth B-phase total current and the fifth C-phase total current;

[0180] The first three-phase weighted current includes a first A-phase weighted current, a first B-phase weighted current, and a first C-phase weighted current;

[0181] The second three-phase weighted current includes a second A-phase weighted current, a second B-phase weighted current, and a second C-phase weighted current;

[0182] The three-phase current of the inverted bus bay includes the phase A current of the inverted bus bay, the phase B current of the inverted bus bay and the phase C current of the inverted bus bay;

[0183] The target bus-couple three-phase current includes a target bus-couple A phase current, a target bus-couple B phase current and a target bus-couple C phase current.

[0184] Based on the above embodiment, optionally, the fourth computing unit is specifically configured to:

[0185] Calculate the target bus tie A phase current according to the first A phase total current, the second A phase total current, the third A phase total current, the fourth A phase total current, the fifth A phase total current, the first A phase weighted current, the second A phase weighted current, the characteristic parameters of the substation to be detected, and the inverted bus bay A phase current;

[0186] Calculate the target bus coupling B-phase current according to the first B-phase total current, the second B-phase total current, the third B-phase total current, the fourth B-phase total current, the fifth B-phase total current, the first B-phase weighted current, the second B-phase weighted current, the characteristic parameters of the substation to be detected, and the inverted bus bay B-phase current;

[0187] Calculate the target bus-tie C-phase current based on the first C-phase total current, the second C-phase total current, the third C-phase total current, the fourth C-phase total current, the fifth C-phase total current, the first C-phase weighted current, the second C-phase weighted current, the characteristic parameters of the substation to be tested, and the inverse bus-interval C-phase current.

[0188] Based on the above embodiment, optionally, the bus coupling interval information further includes actual bus coupling three-phase current value;

[0189] The bus circuit status includes fault status and normal status;

[0190] The bus circuit state determination module includes:

[0191] A current ratio calculation unit, used to calculate a bus coupling A phase current ratio, a bus coupling B phase current ratio and a bus coupling C phase current ratio according to an actual bus coupling three-phase current value and a target bus coupling three-phase current;

[0192] An unbalance calculation unit, used to calculate the unbalance of the bus coupling three-phase current ratio according to the bus coupling A phase current ratio, the bus coupling B phase current ratio and the bus coupling C phase current ratio;

[0193] The judgment unit is used to determine that if the imbalance of the three-phase current ratio of the bus is greater than the imbalance threshold, the bus circuit state is a fault state; if the imbalance of the three-phase current ratio of the bus is less than or equal to the imbalance threshold, the bus circuit state is a normal state.

[0194] Based on the above embodiment, optionally, the imbalance calculation unit is specifically used to:

[0195] Determine the maximum phase current ratio and the minimum phase current ratio among the bus coupling A phase current ratio, the bus coupling B phase current ratio and the bus coupling C phase current ratio;

[0196] According to the maximum phase current ratio and the minimum phase current ratio, the imbalance of the bus three-phase current ratio is calculated.

[0197] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0198] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for diagnosing a bus circuit fault during a hot bus operation, characterized in that: include: According to the busbar topology diagram of the substation to be detected, determine the busbar interval information, the reverse busbar interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be detected, the connection relationship between each of the outgoing line intervals and the first busbar and the second busbar, and the position relationship between each of the outgoing line intervals and the busbar interval and the reverse busbar interval; Determine the target bus-tie three-phase current according to the bus-tie interval information, the reverse bus-tie interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be detected, the connection relationship between each outgoing line interval and the first bus and the second bus, and the position relationship between each outgoing line interval and the bus-tie interval and the reverse bus interval; The bus loop state is determined according to the target bus-couple three-phase current and the bus-couple interval information.

2. The method for diagnosing bus circuit faults in hot bus operation according to claim 1 is characterized in that: The steps of determining the target bus-connection three-phase current include: Calculating the three-phase current of the inverted bus interval according to the inverted bus interval information; Calculating the three-phase current of each outgoing line interval according to the outgoing line interval information of each outgoing line interval; According to the positional relationship between each of the outgoing line intervals and the bus-tie interval and the reverse bus interval, the connection relationship between each of the outgoing line intervals and the first bus and the second bus, and the three-phase current of the outgoing line interval of each of the outgoing line intervals, determine the first three-phase total current of the outgoing line interval located on the side of the bus-tie interval away from the reverse bus interval running on the first bus, the second three-phase total current of the outgoing line interval located on the side of the reverse bus interval away from the bus-tie interval running on the first bus and the third three-phase total current of the outgoing line interval running on the second bus, the fourth three-phase total current of the outgoing line interval located between the reverse bus interval and the bus-tie interval running on the first bus and the fifth three-phase total current of the outgoing line interval running on the second bus, the first three-phase weighted current between the bus-tie interval and the reverse bus interval on the first bus, and the second three-phase weighted current between the bus-tie interval and the reverse bus interval on the second bus; The target bus three-phase current is calculated based on the first three-phase total current, the second three-phase total current, the third three-phase total current, the fourth three-phase total current, the fifth three-phase total current, the first three-phase weighted current, the second three-phase weighted current, the characteristic parameters of the substation to be detected, and the reverse bus interval three-phase current.

3. The method for diagnosing bus circuit faults in hot bus operation according to claim 2 is characterized in that: The reverse bus interval information includes reverse bus three-phase current value, reverse bus active power and reverse bus reactive power; The step of calculating the three-phase current of the inverted bus interval includes: Determine the inverted bus phase A of the inverted bus interval phase A current relative to the A phase bus voltage according to the inverted bus active power and the inverted bus reactive power; According to the phase of the inverted mother phase A, determining the phase of the inverted mother phase B and the phase of the inverted mother phase C; The inverted bus interval three-phase current is calculated according to the inverted bus three-phase current value, the inverted bus A phase, the inverted bus B phase and the inverted bus C phase.

4. The method for diagnosing bus circuit faults in hot bus operation according to claim 2, characterized in that: The outgoing line interval information includes the outgoing line three-phase current value, the outgoing line active power and the outgoing line reactive power; The step of calculating the three-phase current of each outgoing line interval comprises: Determine the outgoing line A phase of the A phase current of each outgoing line interval relative to the A phase bus voltage according to the outgoing line active power and the outgoing line reactive power of each outgoing line interval; According to the phase of the outgoing line A phase of each of the outgoing line intervals, determining the phase of the outgoing line B phase and the phase of the outgoing line C phase of each of the outgoing line intervals; The three-phase current of each of the outgoing line intervals is calculated according to the three-phase current value of each of the outgoing line intervals, the phase of the outgoing line A phase, the phase of the outgoing line B phase, and the phase of the outgoing line C phase.

5. The method for diagnosing bus circuit faults in hot bus operation according to claim 2, characterized in that: The first three-phase total current includes a first A-phase total current, a first B-phase total current and a first C-phase total current; The second three-phase total current includes a second A-phase total current, a second B-phase total current and a second C-phase total current; The third three-phase total current includes a third A-phase total current, a third B-phase total current and a third C-phase total current; The fourth three-phase total current includes a fourth A-phase total current, a fourth B-phase total current and a fourth C-phase total current; The fifth three-phase total current includes the fifth A-phase total current, the fifth B-phase total current and the fifth C-phase total current; The first three-phase weighted current includes a first A-phase weighted current, a first B-phase weighted current and a first C-phase weighted current; The second three-phase weighted current includes a second A-phase weighted current, a second B-phase weighted current and a second C-phase weighted current; The three-phase current of the inverted bus interval includes the A-phase current of the inverted bus interval, the B-phase current of the inverted bus interval and the C-phase current of the inverted bus interval; The target bus-couple three-phase current includes a target bus-couple A phase current, a target bus-couple B phase current and a target bus-couple C phase current.

6. The method for diagnosing bus circuit faults in hot bus operation according to claim 5, characterized in that: The step of calculating the target bus-tie three-phase current comprises: Calculate the target bus-tie A-phase current according to the first A-phase total current, the second A-phase total current, the third A-phase total current, the fourth A-phase total current, the fifth A-phase total current, the first A-phase weighted current, the second A-phase weighted current, the characteristic parameter of the substation to be detected, and the inverted bus bay A-phase current; Calculate the target bus-tie B-phase current according to the first B-phase total current, the second B-phase total current, the third B-phase total current, the fourth B-phase total current, the fifth B-phase total current, the first B-phase weighted current, the second B-phase weighted current, the characteristic parameter of the substation to be detected, and the inverted bus bay B-phase current; The target bus-tie C-phase current is calculated based on the first C-phase total current, the second C-phase total current, the third C-phase total current, the fourth C-phase total current, the fifth C-phase total current, the first C-phase weighted current, the second C-phase weighted current, the characteristic parameters of the substation to be detected, and the inverse bus-interval C-phase current.

7. The method for diagnosing bus circuit faults in hot bus operation according to claim 6, characterized in that: The substation characteristic parameters to be detected include the impedance of the busbar section between adjacent bays, the impedance of the disconnector and the impedance of the bus tie circuit breaker; The target busbar A phase current I A for: Wherein, N is the number of the outgoing line intervals between the reverse bus interval and the bus coupling interval, I 1A is the total current of the first phase A, I 4A is the total current of the fourth phase A, I 2A is the total current of the second phase A, I DA is the A-phase current of the inverted bus bay, I 3A is the total current of the third phase A, I 5A is the total current of the fifth phase A, N 1A is the first A-phase weighted current, N 2A is the second phase A weighted current, Z L is the impedance of the busbar section between the adjacent bays, Z D is the isolating switch impedance, Z S is the bus tie circuit breaker impedance; The target busbar B phase current I B for: Wherein, N is the number of the outgoing line intervals between the reverse bus interval and the bus coupling interval, I 1B is the total current of the first phase B, I 4B is the total current of the fourth B phase, I 2B is the total current of the second phase B, I DB is the phase B current of the inverted bus bay, I 3B is the total current of the third phase B, I 5B is the total current of the fifth phase B, N 1B is the first B-phase weighted current, N 2B is the second B-phase weighted current; The target busbar C phase current I C for: Wherein, N is the number of the outgoing line intervals between the reverse bus interval and the bus coupling interval, I 1C is the total current of the first phase C, I 4C is the total current of the fourth phase C, I 2C is the total current of the second phase C, I DC is the C-phase current of the inverted bus bay, I 3C is the total current of the third phase C, I 5C is the total current of the fifth phase C, N 1C is the first C phase weighted current, N 2C is the second C-phase weighted current.

8. The method for diagnosing bus circuit faults in hot bus operation according to claim 1, characterized in that: The bus coupling interval information also includes actual bus coupling three-phase current value; The bus circuit state includes a fault state and a normal state; The determining of the bus circuit state comprises: Calculate the bus coupling A phase current ratio, the bus coupling B phase current ratio and the bus coupling C phase current ratio according to the actual bus coupling three-phase current value and the target bus coupling three-phase current; Calculate the imbalance of the bus coupling three-phase current ratio according to the bus coupling A phase current ratio, the bus coupling B phase current ratio and the bus coupling C phase current ratio; If the unbalance degree of the busbar three-phase current ratio is greater than the unbalance degree threshold, the busbar loop state is a fault state; If the unbalance degree of the busbar three-phase current ratio is less than or equal to the unbalance degree threshold, the busbar loop state is normal.

9. The method for diagnosing bus circuit faults in hot bus operation according to claim 8, characterized in that: The step of calculating the unbalance degree of the bus-connecting three-phase current ratio comprises: Determine a maximum phase current ratio and a minimum phase current ratio among the bus coupling A phase current ratio, the bus coupling B phase current ratio, and the bus coupling C phase current ratio; The unbalance degree of the bus-connecting three-phase current ratio is calculated according to the maximum phase current ratio and the minimum phase current ratio.

10. A bus circuit fault diagnosis device for hot-reversal operation, characterized in that: include: An acquisition module is used to determine the busbar interval information, the reverse busbar interval information, the outgoing line interval information of each outgoing line interval, the characteristic parameters of the substation to be detected, the connection relationship between each outgoing line interval and the first busbar and the second busbar, and the position relationship between each outgoing line interval and the busbar interval and the reverse busbar interval according to the busbar topology diagram of the substation to be detected; A target bus-tie three-phase current determination module, configured to determine the target bus-tie three-phase current according to the bus-tie interval information, the reverse bus interval information, the outgoing line interval information of each of the outgoing line intervals, the characteristic parameters of the substation to be detected, the connection relationship between each of the outgoing line intervals and the first bus and the second bus, and the positional relationship between each of the outgoing line intervals and the bus-tie intervals and the reverse bus intervals; The bus circuit state determination module is used to determine the bus circuit state according to the target bus three-phase current and the bus interval information.

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