Reactor saturation and turn-to-turn fault identification method and system

Abstract

The invention discloses a reactor saturation and turn-to-turn fault identification method and system, and the method comprises the steps: collecting three-phase voltage and three-phase current of a shunt reactor, and calculating an electrical characteristic value according to the three-phase voltage and the three-phase current; according to the electrical characteristic value, saturation characteristic identification of the shunt reactor is carried out, and when the saturation locking condition is met, turn-to-turn protection is locked immediately to prevent misoperation of the turn-to-turn protection; and fault characteristic identification of the shunt reactor is carried out according to the electrical characteristic value, and when the fault opening condition is satisfied and the duration time of the satisfied condition reaches a set time delay, turn-to-turn short circuit protection action is opened. The method has general applicability to coil equipment such as electric reactors, transformers and the like, and can solve similar problems existing in electric reactor saturation and transformer inrush current identification.

Description

Technical Field

[0001] The present invention relates to the technical field of relay protection of power systems, and more specifically, to a method and system for identifying reactor saturation and turn-to-turn faults. Background Art

[0002] High-voltage shunt reactor is a large-capacity shunt inductor coil with an iron core. It is similar to a single-winding transformer in structure. It has the functions of reactive power regulation, line potential current supply and system overvoltage suppression in the power system. It is widely installed on the bus or line of the ultra-high voltage transmission system. As an important primary equipment, its stable and reliable operation is directly related to the safety and stability of the power system.

[0003] Commonly used inter-turn protection for high-voltage shunt reactors is usually based on the zero-sequence direction combined with the zero-sequence impedance principle. When the shunt reactor core is not saturated, it can better distinguish the reactor inter-turn fault and out-of-zone fault. However, in recent years, there have been cases where the reactor core is saturated due to out-of-zone fault removal, no-charge reactor or circuit breaker tripping line resonance, etc., and its characteristics are similar to those of reactor inter-turn faults. The original inter-turn protection can no longer adapt. When the reactor is saturated, the harmonic components are rich, and a single harmonic braking coefficient is not easy to select. It is urgent to optimize and improve the saturation judgment of the reactor inter-turn protection to ensure the safe and stable operation of the power grid. Summary of the invention

[0004] According to the present invention, a method and system for identifying reactor saturation and inter-turn faults are provided to solve the problem that the reactor core is saturated due to out-of-zone fault removal, no-charge reactor or circuit breaker tripping line resonance, etc., whose characteristics are similar to those of reactor inter-turn faults, and the original inter-turn protection can no longer adapt. When the reactor is saturated, the harmonic components are rich and the single harmonic braking coefficient is not easy to select.

[0005] According to a first aspect of the present invention, a method for identifying reactor saturation and inter-turn fault is provided, comprising:

[0006] Collecting the three-phase voltage and three-phase current of the shunt reactor, and calculating the electrical characteristic value according to the three-phase voltage and the three-phase current;

[0007] Identify the saturation characteristics of the shunt reactor according to the electrical characteristic value, and immediately lock the inter-turn protection when the saturation locking condition is met to prevent the inter-turn protection from malfunctioning;

[0008] The fault characteristic of the shunt reactor is identified according to the electrical characteristic value, and when the fault opening condition is met and the duration of meeting the condition reaches a set delay, the turn-to-turn short-circuit protection action is opened.

[0009] Optionally, identifying the saturation characteristic of the shunt reactor according to the electrical characteristic value includes:

[0010] In response to the establishment of the following criterion, criterion 1, criterion 2 and criterion 3 are satisfied at the same time, it is determined that the saturation lockout condition is satisfied:

[0011] Criterion 1: The ratio of the power frequency fundamental effective value to the RMS value of the differential zero-sequence current produced by the shunt reactor is less than the current ratio setting B1;

[0012] Criterion 2: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence voltage produced by the shunt reactor is less than the voltage ratio setting value B2;

[0013] Criterion 3: The power frequency fundamental effective value of any phase current of the shunt reactor is greater than the phase current constant value I dz ;

[0014] Among them, the ratio of the power frequency fundamental effective value to the root mean square value of the self-produced differential zero-sequence current is the ratio of the power frequency fundamental effective value of the self-produced differential zero-sequence current to the root mean square value of the self-produced differential zero-sequence current, and the ratio of the power frequency fundamental effective value to the root mean square value of the self-produced zero-sequence voltage is the ratio of the power frequency fundamental effective value of the self-produced zero-sequence voltage to the root mean square value of the self-produced zero-sequence voltage.

[0015] Optionally, identifying the fault characteristics of the shunt reactor according to the electrical characteristic value includes:

[0016] In response to the establishment of the following criteria, the fault-opening condition is determined to be satisfied when either criterion 1 or criterion 2 is satisfied at the same time, and criterion 3 and criterion 4 are satisfied at the same time:

[0017] Criterion 1: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence current produced by the shunt reactor is greater than the current ratio setting value B3;

[0018] Criterion 2: The ratio of the power frequency fundamental effective value to the RMS value of the differential zero-sequence current produced by the shunt reactor is greater than the current ratio setting B4;

[0019] Criterion 3: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence voltage produced by the shunt reactor is greater than the voltage ratio setting value B5;

[0020] Criterion 4: The power frequency fundamental effective value of the zero-sequence current produced by the shunt reactor is greater than the zero-sequence current constant I0 dz ;

[0021] The ratio of the effective value of the power frequency fundamental wave to the root mean square value of the self-generated zero-sequence current is the ratio of the effective value of the power frequency fundamental wave of the self-generated zero-sequence current to the root mean square value of the self-generated zero-sequence current.

[0022] Optionally, it also includes:

[0023] The inter-turn protection action is opened, and at the same time, the zero-sequence impedance of the shunt reactor is less than the zero-sequence impedance setting value, and the direction of the zero-sequence impedance satisfies the directional action element, and the inter-turn protection action is executed.

[0024] Optionally, the electrical characteristic values ​​include the power frequency fundamental wave effective value I1 of the three-phase current of the shunt reactor, the power frequency fundamental wave effective value I 01 , the root mean square value of the self-generated zero-sequence current I G , the power frequency fundamental effective value of the self-produced zero-sequence differential current I 0C1 , the RMS value of the self-generated zero-sequence differential current I 0CG , the power frequency fundamental wave effective value of the self-produced zero sequence voltage U 01 , RMS value of self-produced zero-sequence voltage U 0G .

[0025] According to another aspect of the present invention, there is also a reactor saturation and inter-turn fault identification system, comprising:

[0026] An electrical characteristic value calculation module is used to collect the three-phase voltage and three-phase current of the shunt reactor, and calculate the electrical characteristic value according to the three-phase voltage and the three-phase current;

[0027] A module for preventing malfunction of inter-turn protection is used to identify the saturation characteristics of the shunt reactor according to the electrical characteristic value, and immediately lock the inter-turn protection when the saturation locking condition is met to prevent malfunction of the inter-turn protection;

[0028] The turn-to-turn short-circuit protection action module is used to identify the fault characteristics of the shunt reactor according to the electrical characteristic value, and when the fault opening condition is met and the duration of meeting the condition reaches a set delay, the turn-to-turn short-circuit protection action is opened.

[0029] Optionally, a module for preventing false operation of turn-to-turn protection includes:

[0030] The submodule for determining whether the saturation blocking condition is satisfied is used to determine whether the saturation blocking condition is satisfied in response to the establishment of the following criteria, and when criteria 1, 2, and 3 are satisfied at the same time:

[0031] Criterion 1: The ratio of the power frequency fundamental effective value to the RMS value of the differential zero-sequence current produced by the shunt reactor is less than the current ratio setting B1;

[0032] Criterion 2: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence voltage produced by the shunt reactor is less than the voltage ratio setting value B2;

[0033] Criterion 3: The power frequency fundamental effective value of any phase current of the shunt reactor is greater than the phase current constant value I dz ;

[0034] Among them, the ratio of the power frequency fundamental effective value to the root mean square value of the self-produced differential zero-sequence current is the ratio of the power frequency fundamental effective value of the self-produced differential zero-sequence current to the root mean square value of the self-produced differential zero-sequence current, and the ratio of the power frequency fundamental effective value to the root mean square value of the self-produced zero-sequence voltage is the ratio of the power frequency fundamental effective value of the self-produced zero-sequence voltage to the root mean square value of the self-produced zero-sequence voltage.

[0035] Optionally, the open turn-to-turn short-circuit protection action module includes:

[0036] In response to the establishment of the following criteria, the fault-opening condition is determined to be satisfied when either criterion 1 or criterion 2 is satisfied at the same time, and criterion 3 and criterion 4 are satisfied at the same time:

[0037] Criterion 1: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence current produced by the shunt reactor is greater than the current ratio setting value B3;

[0038] Criterion 2: The ratio of the power frequency fundamental effective value to the RMS value of the differential zero-sequence current produced by the shunt reactor is greater than the current ratio setting B4;

[0039] Criterion 3: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence voltage produced by the shunt reactor is greater than the voltage ratio setting value B5;

[0040] Criterion 4: The power frequency fundamental effective value of the zero-sequence current produced by the shunt reactor is greater than the zero-sequence current constant I0 dz ;

[0041] The ratio of the effective value of the power frequency fundamental wave to the root mean square value of the self-generated zero-sequence current is the ratio of the effective value of the power frequency fundamental wave of the self-generated zero-sequence current to the root mean square value of the self-generated zero-sequence current.

[0042] Optionally, it also includes:

[0043] The inter-turn protection action module is executed to open the inter-turn protection action. At the same time, the zero-sequence impedance of the shunt reactor is less than the zero-sequence impedance setting value, and the direction of the zero-sequence impedance satisfies the directional action element to execute the inter-turn protection action.

[0044] According to another aspect of the present invention, there is further provided a computer-readable storage medium on which a computer program is stored, and when the program is executed by a processor, the steps of any of the above methods are implemented.

[0045] Therefore, by using the current and voltage data of the reactor equipment, the ratio of the effective value and the root mean square value is calculated, and the saturation characteristics and fault characteristics of the reactor equipment are creatively processed to improve the discrimination efficiency and solve the problem of reactor saturation identification. It can realize rapid data collection and analysis, greatly improve the reliability of the protection equipment, improve the sensitivity of the internal turn-to-turn fault identification of the reactor equipment, and reduce the risk of saturation turn-to-turn protection misoperation of the reactor equipment, thereby effectively improving the safe operation level of the power grid. The reactor saturation and turn-to-turn fault identification device can complete data extraction and analysis within 30ms, and automatically make an open turn-to-turn short-circuit protection action, or lock the turn-to-turn short-circuit protection action, greatly improving the reliability and discrimination efficiency of the relay protection work. It is generally applicable to coil equipment such as reactors and transformers, and can solve similar problems in reactor saturation and transformer inrush current identification. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] A more complete understanding of exemplary embodiments of the present invention may be obtained by referring to the following drawings:

[0047] Figure 1 A schematic flow chart of a method for identifying reactor saturation and inter-turn faults according to this embodiment;

[0048] Figure 2 This is a functional diagram of the modules described in this implementation mode;

[0049] Figure 3 is a schematic diagram of the saturation characteristic value of the reactor according to this embodiment;

[0050] Figure 4 is a schematic diagram of the reactor turn-to-turn fault characteristic value according to the present embodiment;

[0051] Figure 5 Schematic diagram of a reactor saturation and inter-turn fault identification system described in this embodiment. DETAILED DESCRIPTION

[0052] Now, exemplary embodiments of the present invention are described with reference to the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely and to fully convey the scope of the present invention to those skilled in the art. The terms used in the exemplary embodiments shown in the accompanying drawings are not intended to limit the present invention. In the accompanying drawings, the same units / elements are marked with the same reference numerals.

[0053] Unless otherwise specified, the terms (including technical terms) used herein have the commonly understood meanings to those skilled in the art. In addition, it is understood that the terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0054] According to a first aspect of the present invention, a method 100 for identifying reactor saturation and turn-to-turn faults is provided. Figure 1 As shown, the method 100 includes:

[0055] S101: collecting three-phase voltage and three-phase current of the shunt reactor, and calculating electrical characteristic values ​​according to the three-phase voltage and the three-phase current;

[0056] S102: Identify the saturation characteristics of the shunt reactor according to the electrical characteristic value, and immediately lock the turn-to-turn protection if the saturation locking condition is met to prevent the turn-to-turn protection from malfunctioning;

[0057] S103: Identify the fault characteristics of the shunt reactor according to the electrical characteristic value, and if the fault opening condition is met and the duration of meeting the condition reaches a set delay, open the turn-to-turn short-circuit protection action.

[0058] Specifically, refer to Figure 2 As shown, the three-phase voltage and three-phase current of the shunt reactor are collected; the electrical characteristic value is calculated according to the three-phase voltage and the three-phase current;

[0059] Identify the saturation characteristics of the shunt reactor according to the electrical characteristic value; immediately lock the inter-turn protection when the saturation locking condition is met to prevent the inter-turn protection from malfunctioning;

[0060] Identify the fault characteristics of the shunt reactor according to the electrical characteristic value; when the fault opening condition is met and the duration of meeting the condition reaches a set delay, open the turn-to-turn short-circuit protection action;

[0061] The electrical characteristic values ​​include the power frequency fundamental effective value I1 of the three-phase current of the shunt reactor, the power frequency fundamental effective value I 01 , the root mean square value of the self-generated zero-sequence current I G , the power frequency fundamental effective value of the self-produced zero-sequence differential current I 0C1 , the RMS value of the self-generated zero-sequence differential current I 0CG , the power frequency fundamental wave effective value of the self-produced zero sequence voltage U 01 , RMS value of self-produced zero-sequence voltage U 0G .

[0062] Identifying the saturation characteristics of the shunt reactor according to the electrical characteristic value includes: in response to the establishment of the following criteria, while satisfying criteria 1, 2 and 3, determining that the saturation lockout condition is satisfied:

[0063] Criterion 1: The ratio of the power frequency fundamental effective value to the RMS value of the differential zero-sequence current produced by the shunt reactor is less than the current ratio setting B1;

[0064] Criterion 2: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence voltage produced by the shunt reactor is less than the voltage ratio setting value B2;

[0065] Criterion 3: The power frequency fundamental effective value of any phase current of the shunt reactor is greater than the phase current constant value I dz ;

[0066] Among them, the ratio of the power frequency fundamental effective value to the root mean square value of the self-produced differential zero-sequence current is the ratio of the power frequency fundamental effective value of the self-produced differential zero-sequence current to the root mean square value of the self-produced differential zero-sequence current, and the ratio of the power frequency fundamental effective value to the root mean square value of the self-produced zero-sequence voltage is the ratio of the power frequency fundamental effective value of the self-produced zero-sequence voltage to the root mean square value of the self-produced zero-sequence voltage.

[0067] Identifying the fault characteristics of the shunt reactor according to the electrical characteristic value includes: in response to the establishment of the following criteria, simultaneously satisfying criteria 1 or criteria 2, and simultaneously satisfying criteria 3 and criteria 4, determining that the fault opening condition is satisfied:

[0068] Criterion 1: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence current produced by the shunt reactor is greater than the current ratio setting value B3;

[0069] Criterion 2: The ratio of the power frequency fundamental effective value to the RMS value of the differential zero-sequence current produced by the shunt reactor is greater than the current ratio setting B4;

[0070] Criterion 3: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence voltage produced by the shunt reactor is greater than the voltage ratio setting value B5;

[0071] Criterion 4: The power frequency fundamental effective value of the zero-sequence current produced by the shunt reactor is greater than the zero-sequence current constant I0 dz ;

[0072] The ratio of the effective value of the power frequency fundamental wave to the root mean square value of the self-generated zero-sequence current is the ratio of the effective value of the power frequency fundamental wave of the self-generated zero-sequence current to the root mean square value of the self-generated zero-sequence current.

[0073] When the electrical characteristic value meets the saturation blocking condition, the turn-to-turn protection is immediately blocked.

[0074] The electrical characteristic value meets the fault opening condition, and the duration of meeting the fault opening condition reaches the set delay t1, and the inter-turn protection action is opened.

[0075] The inter-turn protection action is opened, and at the same time, the zero-sequence impedance of the shunt reactor is less than the zero-sequence impedance setting value, and the direction of the zero-sequence impedance satisfies the directional action element, and the inter-turn protection action is executed.

[0076] The saturation characteristics are identified by using the zero-sequence current and voltage power frequency fundamental effective value RMS value ratio proposed in this paper. Figure 3 It can be seen that the ratio of the zero-sequence current and voltage power frequency fundamental effective value RMS value f3U0, f3I0, and f3I0C in normal non-full-phase condition is in the range of 0.951 to 0.982, which is reduced to 0.209 to 0.697 when the reactor is saturated. The phase current at the first end of the high-voltage reactor increases to more than 4 times the load current, and the zero-sequence current 3I0 exceeds 0.5A.

[0077] The inter-turn fault characteristics are identified by using the zero-sequence current and voltage power frequency fundamental effective value RMS ratio proposed in this paper. Figure 4 It can be seen that when the reactor has an inter-turn fault, the ratio of the zero-sequence current to the RMS value of the voltage at the power frequency fundamental wave, f3U0, f3I0, and f3I0C, ranges from 0.967 to 1.0, the phase current CT19 increases to more than 3 times the load current, and the zero-sequence current 3I0 is close to 0.5A.

[0078] Optionally, identifying the saturation characteristic of the shunt reactor according to the electrical characteristic value includes:

[0079] In response to the establishment of the following criterion, criterion 1, criterion 2 and criterion 3 are satisfied at the same time, it is determined that the saturation lockout condition is satisfied:

[0080] Criterion 1: The ratio of the power frequency fundamental effective value to the RMS value of the differential zero-sequence current produced by the shunt reactor is less than the current ratio setting B1;

[0081] Criterion 2: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence voltage produced by the shunt reactor is less than the voltage ratio setting value B2;

[0082] Criterion 3: The power frequency fundamental effective value of any phase current of the shunt reactor is greater than the phase current constant value I dz ;

[0083] Among them, the ratio of the power frequency fundamental effective value to the root mean square value of the self-produced differential zero-sequence current is the ratio of the power frequency fundamental effective value of the self-produced differential zero-sequence current to the root mean square value of the self-produced differential zero-sequence current, and the ratio of the power frequency fundamental effective value to the root mean square value of the self-produced zero-sequence voltage is the ratio of the power frequency fundamental effective value of the self-produced zero-sequence voltage to the root mean square value of the self-produced zero-sequence voltage.

[0084] Optionally, identifying the fault characteristics of the shunt reactor according to the electrical characteristic value includes:

[0085] In response to the establishment of the following criteria, the fault-opening condition is determined to be satisfied when either criterion 1 or criterion 2 is satisfied at the same time, and criterion 3 and criterion 4 are satisfied at the same time:

[0086] Criterion 1: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence current produced by the shunt reactor is greater than the current ratio setting value B3;

[0087] Criterion 2: The ratio of the power frequency fundamental effective value to the RMS value of the differential zero-sequence current produced by the shunt reactor is greater than the current ratio setting B4;

[0088] Criterion 3: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence voltage produced by the shunt reactor is greater than the voltage ratio setting value B5;

[0089] Criterion 4: The power frequency fundamental effective value of the zero-sequence current produced by the shunt reactor is greater than the zero-sequence current constant I0 dz ;

[0090] The ratio of the effective value of the power frequency fundamental wave to the root mean square value of the self-generated zero-sequence current is the ratio of the effective value of the power frequency fundamental wave of the self-generated zero-sequence current to the root mean square value of the self-generated zero-sequence current.

[0091] Optionally, it also includes:

[0092] The inter-turn protection action is opened, and at the same time, the zero-sequence impedance of the shunt reactor is less than the zero-sequence impedance setting value, and the direction of the zero-sequence impedance satisfies the directional action element, and the inter-turn protection action is executed.

[0093] Optionally, the electrical characteristic values ​​include the power frequency fundamental wave effective value I1 of the three-phase current of the shunt reactor, the power frequency fundamental wave effective value I 01 , the root mean square value of the self-generated zero-sequence current I G , the power frequency fundamental effective value of the self-produced zero-sequence differential current I 0C1 , the RMS value of the self-generated zero-sequence differential current I 0CG , the power frequency fundamental wave effective value of the self-produced zero sequence voltage U 01 , RMS value of self-produced zero-sequence voltage U 0G .

[0094] Therefore, by using the current and voltage data of the reactor equipment, the ratio of the effective value and the root mean square value is calculated, and the saturation characteristics and fault characteristics of the reactor equipment are creatively processed to improve the discrimination efficiency and solve the problem of reactor saturation identification. It can realize rapid data collection and analysis, greatly improve the reliability of the protection equipment, improve the sensitivity of the internal turn-to-turn fault identification of the reactor equipment, and reduce the risk of saturation turn-to-turn protection misoperation of the reactor equipment, thereby effectively improving the safe operation level of the power grid. The reactor saturation and turn-to-turn fault identification device can complete data extraction and analysis within 30ms, and automatically make an open turn-to-turn short-circuit protection action, or lock the turn-to-turn short-circuit protection action, greatly improving the reliability and discrimination efficiency of the relay protection work. It is generally applicable to coil equipment such as reactors and transformers, and can solve similar problems in reactor saturation and transformer inrush current identification.

[0095] According to another aspect of the present invention, a reactor saturation and turn-to-turn fault identification system 500 is provided. Figure 5 As shown, the system 500 includes:

[0096] An electrical characteristic value calculation module 510 is used to collect the three-phase voltage and the three-phase current of the shunt reactor, and calculate the electrical characteristic value according to the three-phase voltage and the three-phase current;

[0097] The module 520 for preventing malfunction of inter-turn protection is used to identify the saturation characteristics of the shunt reactor according to the electrical characteristic value, and immediately lock the inter-turn protection when the saturation locking condition is met to prevent malfunction of the inter-turn protection;

[0098] The turn-to-turn short-circuit protection action module 530 is used to identify the fault characteristics of the shunt reactor according to the electrical characteristic value, and to open the turn-to-turn short-circuit protection action when the fault opening condition is met and the duration of meeting the condition reaches a set delay.

[0099] Optionally, a module for preventing false operation of turn-to-turn protection includes:

[0100] The submodule for determining whether the saturation blocking condition is satisfied is used to determine whether the saturation blocking condition is satisfied in response to the establishment of the following criteria, and when criteria 1, 2, and 3 are satisfied at the same time:

[0101] Criterion 1: The ratio of the power frequency fundamental effective value to the RMS value of the differential zero-sequence current produced by the shunt reactor is less than the current ratio setting B1;

[0102] Criterion 2: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence voltage produced by the shunt reactor is less than the voltage ratio setting value B2;

[0103] Criterion 3: The power frequency fundamental effective value of any phase current of the shunt reactor is greater than the phase current constant value I dz ;

[0104] Among them, the ratio of the power frequency fundamental effective value to the root mean square value of the self-produced differential zero-sequence current is the ratio of the power frequency fundamental effective value of the self-produced differential zero-sequence current to the root mean square value of the self-produced differential zero-sequence current, and the ratio of the power frequency fundamental effective value to the root mean square value of the self-produced zero-sequence voltage is the ratio of the power frequency fundamental effective value of the self-produced zero-sequence voltage to the root mean square value of the self-produced zero-sequence voltage.

[0105] Optionally, the open turn-to-turn short-circuit protection action module includes:

[0106] In response to the establishment of the following criteria, the fault-opening condition is determined to be satisfied when either criterion 1 or criterion 2 is satisfied at the same time, and criterion 3 and criterion 4 are satisfied at the same time:

[0107] Criterion 1: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence current produced by the shunt reactor is greater than the current ratio setting value B3;

[0108] Criterion 2: The ratio of the power frequency fundamental effective value to the RMS value of the differential zero-sequence current produced by the shunt reactor is greater than the current ratio setting B4;

[0109] Criterion 3: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence voltage produced by the shunt reactor is greater than the voltage ratio setting value B5;

[0110] Criterion 4: The power frequency fundamental effective value of the zero-sequence current produced by the shunt reactor is greater than the zero-sequence current constant I0 dz ;

[0111] The ratio of the effective value of the power frequency fundamental wave to the root mean square value of the self-generated zero-sequence current is the ratio of the effective value of the power frequency fundamental wave of the self-generated zero-sequence current to the root mean square value of the self-generated zero-sequence current.

[0112] Optionally, it also includes:

[0113] The inter-turn protection action module is executed to open the inter-turn protection action. At the same time, the zero-sequence impedance of the shunt reactor is less than the zero-sequence impedance setting value, and the direction of the zero-sequence impedance satisfies the directional action element to execute the inter-turn protection action.

[0114] A reactor saturation and turn-to-turn fault identification system 500 according to an embodiment of the present invention corresponds to a reactor saturation and turn-to-turn fault identification method 100 according to another embodiment of the present invention, and will not be described in detail herein.

[0115] According to another aspect of the present invention, there is further provided a computer-readable storage medium on which a computer program is stored, and when the program is executed by a processor, the steps of any of the above methods are implemented.

[0116] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0117] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0118] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0119] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0120] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0121] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A method for identifying reactor saturation and inter-turn faults, characterized in that: include: Collecting the three-phase voltage and three-phase current of the shunt reactor, and calculating the electrical characteristic value according to the three-phase voltage and the three-phase current; Identify the saturation characteristics of the shunt reactor according to the electrical characteristic value, and immediately lock the turn-to-turn protection when the saturation locking condition is met to prevent the turn-to-turn protection from malfunctioning; The fault characteristic of the shunt reactor is identified according to the electrical characteristic value, and when the fault opening condition is met and the duration of meeting the condition reaches a set delay, the turn-to-turn short-circuit protection action is opened.

2. The method according to claim 1, characterized in that The saturation characteristic of the shunt reactor is identified according to the electrical characteristic value, including: In response to the establishment of the following criterion, criterion 1, criterion 2 and criterion 3 are satisfied at the same time, it is determined that the saturation lockout condition is satisfied: Criterion 1: The ratio of the power frequency fundamental effective value to the RMS value of the differential zero-sequence current produced by the shunt reactor is less than the current ratio setting B1; Criterion 2: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence voltage produced by the shunt reactor is less than the voltage ratio setting value B2; Criterion 3: The power frequency fundamental effective value of any phase current of the shunt reactor is greater than the phase current constant value I dz ; Among them, the ratio of the power frequency fundamental effective value to the root mean square value of the self-produced differential zero-sequence current is the ratio of the power frequency fundamental effective value of the self-produced differential zero-sequence current to the root mean square value of the self-produced differential zero-sequence current, and the ratio of the power frequency fundamental effective value to the root mean square value of the self-produced zero-sequence voltage is the ratio of the power frequency fundamental effective value of the self-produced zero-sequence voltage to the root mean square value of the self-produced zero-sequence voltage.

3. The method according to claim 1, characterized in that The fault characteristic of the shunt reactor is identified according to the electrical characteristic value, including: In response to the establishment of the following criteria, the fault-opening condition is determined to be satisfied when either criterion 1 or criterion 2 is satisfied at the same time, and criterion 3 and criterion 4 are satisfied at the same time: Criterion 1: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence current produced by the shunt reactor is greater than the current ratio setting value B3; Criterion 2: The ratio of the power frequency fundamental effective value to the RMS value of the differential zero-sequence current produced by the shunt reactor is greater than the current ratio setting B4; Criterion 3: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence voltage produced by the shunt reactor is greater than the voltage ratio setting value B5; Criterion 4: The power frequency fundamental effective value of the zero-sequence current produced by the shunt reactor is greater than the zero-sequence current constant I0 dz ; The ratio of the effective value of the power frequency fundamental wave to the root mean square value of the self-generated zero-sequence current is the ratio of the effective value of the power frequency fundamental wave of the self-generated zero-sequence current to the root mean square value of the self-generated zero-sequence current.

4. The method according to claim 1, characterized in that: Also includes: The inter-turn protection action is opened, and at the same time, the zero-sequence impedance of the shunt reactor is less than the zero-sequence impedance setting value, and the direction of the zero-sequence impedance satisfies the directional action element, and the inter-turn protection action is executed.

5. The method according to claim 1, characterized in that The electrical characteristic values ​​include the power frequency fundamental wave effective value I1 of the three-phase current of the shunt reactor, the power frequency fundamental wave effective value I 01 , the root mean square value of the self-generated zero-sequence current I G , the power frequency fundamental effective value of the self-produced zero-sequence differential current I 0C1 , the RMS value of the self-generated zero-sequence differential current I 0CG , the power frequency fundamental wave effective value of the self-produced zero sequence voltage U 01 , RMS value of self-produced zero-sequence voltage U 0G .

6. A reactor saturation and inter-turn fault identification system, characterized in that: include: An electrical characteristic value calculation module is used to collect the three-phase voltage and three-phase current of the shunt reactor, and calculate the electrical characteristic value according to the three-phase voltage and the three-phase current; A module for preventing malfunction of inter-turn protection is used to identify the saturation characteristics of the shunt reactor according to the electrical characteristic value, and immediately lock the inter-turn protection when the saturation locking condition is met to prevent malfunction of the inter-turn protection; The turn-to-turn short-circuit protection action module is used to identify the fault characteristics of the shunt reactor according to the electrical characteristic value, and when the fault opening condition is met and the duration of meeting the condition reaches a set delay, the turn-to-turn short-circuit protection action is opened.

7. The system according to claim 6, characterized in that The module for preventing false operation of inter-turn protection includes: The submodule for determining whether the saturation blocking condition is satisfied is used to determine whether the saturation blocking condition is satisfied in response to the establishment of the following criteria, and when criteria 1, 2, and 3 are satisfied at the same time: Criterion 1: The ratio of the power frequency fundamental effective value to the RMS value of the differential zero-sequence current produced by the shunt reactor is less than the current ratio setting B1; Criterion 2: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence voltage produced by the shunt reactor is less than the voltage ratio setting value B2; Criterion 3: The power frequency fundamental effective value of any phase current of the shunt reactor is greater than the phase current constant value I dz ; Among them, the ratio of the power frequency fundamental effective value to the root mean square value of the self-produced differential zero-sequence current is the ratio of the power frequency fundamental effective value of the self-produced differential zero-sequence current to the root mean square value of the self-produced differential zero-sequence current, and the ratio of the power frequency fundamental effective value to the root mean square value of the self-produced zero-sequence voltage is the ratio of the power frequency fundamental effective value of the self-produced zero-sequence voltage to the root mean square value of the self-produced zero-sequence voltage.

8. The system according to claim 7, characterized in that Open turn-to-turn short-circuit protection action module, including: In response to the establishment of the following criteria, the fault-opening condition is determined to be satisfied when either criterion 1 or criterion 2 is satisfied at the same time, and criterion 3 and criterion 4 are satisfied at the same time: Criterion 1: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence current produced by the shunt reactor is greater than the current ratio setting value B3; Criterion 2: The ratio of the power frequency fundamental effective value to the RMS value of the differential zero-sequence current produced by the shunt reactor is greater than the current ratio setting B4; Criterion 3: The ratio of the power frequency fundamental wave effective value to the RMS value of the zero-sequence voltage produced by the shunt reactor is greater than the voltage ratio setting value B5; Criterion 4: The power frequency fundamental effective value of the zero-sequence current produced by the shunt reactor is greater than the zero-sequence current constant I0 dz ; The ratio of the effective value of the power frequency fundamental wave to the root mean square value of the self-generated zero-sequence current is the ratio of the effective value of the power frequency fundamental wave of the self-generated zero-sequence current to the root mean square value of the self-generated zero-sequence current.

9. The system according to claim 6, characterized in that Also includes: The inter-turn protection action module is executed to open the inter-turn protection action. At the same time, the zero-sequence impedance of the shunt reactor is less than the zero-sequence impedance setting value, and the direction of the zero-sequence impedance satisfies the directional action element to execute the inter-turn protection action.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

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