Three-phase inconsistency protection method and system for high-voltage circuit breaker of transformer substation

Abstract

The invention discloses a three-phase inconsistency protection method and system for a high-voltage circuit breaker of a transformer substation. The method comprises the following steps: determining the load rate of a main transformer of the substation; forming a current protection criterion of three-phase inconsistent protection of the high-voltage circuit breaker according to the load rate; determining the Dess similarity between the voltages at the two ends of each corresponding high-voltage circuit breaker; forming a voltage protection criterion of three-phase inconsistent protection of the high-voltage circuit breaker according to the Dess similarity; and judging whether to execute the three-phase inconsistent protection of the high-voltage circuit breaker according to the current protection criterion and at least one corresponding voltage protection criterion. According to the method, the zero-sequence current protection sensitivity and the negative-sequence current protection sensitivity are improved by combining the real-time load rate of the transformer for the first time, the Dice-based similarity voltage protection method is proposed for the first time, and compared with a traditional similarity algorithm, the method has better sensitivity and robustness.

Description

Technical Field

[0001] The present invention relates to the field of high-voltage electrical technologies, and in particular, to a three-phase inconsistency protection method and system for high-voltage circuit breakers in a substation. Background Art

[0002] The three-phase inconsistency protection of high-voltage circuit breakers on the high-voltage side of a substation is divided into two categories according to the implementation method: one is the in-breaker body three-phase inconsistency protection configured inside the circuit breaker; the other is the microcomputer three-phase inconsistency protection configured in the protection device. Some scholars have carried out a series of studies on these two protection methods: for the in-breaker body three-phase inconsistency protection, the secondary circuit of the circuit breaker is optimized to improve the anti-interference ability of the three-phase inconsistency protection and can overcome the adverse factors such as the damage of the outlet relay. Furthermore, some scholars have proposed the design idea of the anti-pumping circuit of the circuit breaker to avoid the phenomenon of repeated opening and closing of the circuit breaker under the non-full-phase condition; aiming at the problem of misoperation of the three-phase inconsistency protection caused by the failure of the relay or contactor and the deviation of the action time, a high-reliability improvement scheme for the secondary circuit is proposed; an improved method for the three-phase inconsistency protection of the circuit breaker based on the auxiliary contacts of the double-position relay is proposed to improve the high reliability of the circuit breaker in the non-open and non-closed state. For the microcomputer three-phase inconsistency protection, some scholars have discussed issues such as the setting calculation and time-delay coordination of the three-phase inconsistency protection to achieve its time-sequence coordination with the grid protection and fault reclosing; the phase characteristics of the stator three-phase current under different transformer connection groups are analyzed to detect the number of opened phases of the three-phase inconsistency fault. Some scholars have found that the main transformer differential protection can operate reliably without misoperation during the non-full-phase operation of the system, but the generator composite voltage overcurrent protection may start, and its action time delay needs to be coordinated with the circuit breaker reclosing time. Summary of the Invention

[0003] In order to solve the above technical problems, an embodiment of the present application provides a three-phase inconsistency protection method for high-voltage circuit breakers in a substation, and also provides a three-phase inconsistency protection system for high-voltage circuit breakers in a substation, and proposes a three-phase inconsistency protection method different from the common one: a current protection criterion formed according to the load rate of the main transformer and a voltage protection criterion formed based on the Dice similarity jointly constitute the three-phase inconsistency protection criterion, and for the first time, the sensitivity of the zero-sequence and negative-sequence current protection is improved by combining the real-time load rate of the transformer; and for the first time, a voltage protection criterion formed based on the Dice similarity is proposed, which has better sensitivity and robustness than the traditional similarity algorithm.

[0004] In a first aspect, an embodiment of the present application provides a method for protecting a three-phase inconsistency of a high-voltage circuit breaker in a substation, including: determining a load rate of a main transformer of the substation; constituting a current protection criterion for protecting the three-phase inconsistency of the high-voltage circuit breaker according to the load rate; determining a Dice similarity between voltages at both ends of each corresponding high-voltage circuit breaker; constituting a voltage protection criterion for protecting the three-phase inconsistency of the high-voltage circuit breaker according to the Dice similarity; and judging whether to execute the protection for the three-phase inconsistency of the high-voltage circuit breaker according to the current protection criterion and at least one corresponding voltage protection criterion.

[0005] Determining the load rate of the main transformer of the substation as described above includes: determining the apparent power and rated capacity of the main transformer; and determining the load rate according to the apparent power and the rated capacity, where the load rate is the apparent power divided by the rated capacity.

[0006] The current protection criterion as described above includes a negative-sequence current criterion and / or a zero-sequence current criterion; constituting the current protection criterion for protecting the three-phase inconsistency of the high-voltage circuit breaker according to the load rate includes: determining a first threshold and a second threshold according to the load rate and the rated phase current on the high-voltage side of the main transformer; acquiring the three-phase currents on the high-voltage side of the main transformer of the substation, and obtaining a zero-sequence current and a negative-sequence current according to the three-phase currents; determining the zero-sequence current criterion according to the zero-sequence current and the first threshold; and determining the negative-sequence current criterion according to the negative-sequence current and the second threshold.

[0007] Determining the zero-sequence current criterion according to the zero-sequence current and the first threshold as described above includes: determining a product of a first coefficient and the zero-sequence current as a first product; and obtaining the zero-sequence current criterion according to the first product and the first threshold; where, when the first product is greater than or equal to the first threshold, obtaining the zero-sequence current criterion includes activating the protection for the three-phase inconsistency of the high-voltage circuit breaker.

[0008] Determining the negative-sequence current criterion according to the negative-sequence current and the second threshold as described above includes: comparing a current value of the negative-sequence current with the second threshold to obtain the negative-sequence current criterion; where, when the current value of the negative-sequence current is greater than or equal to the second threshold, obtaining the negative-sequence current criterion includes activating the protection for the three-phase inconsistency of the high-voltage circuit breaker.

[0009] Determining the voltage protection criterion according to the Dice similarity and a set similarity as described above includes: comparing the Dice similarity with the set similarity to obtain the voltage protection criterion; where, when the Dice similarity is less than or equal to the set similarity, obtaining the voltage protection criterion includes activating the protection for the three-phase inconsistency of the high-voltage circuit breaker.

[0010] Determining a first threshold according to the load rate and the rated phase current on the high-voltage side of the main transformer as described above includes: determining the product between the load rate and the rated phase current as a second product; and determining the product between a second coefficient and the second product as the first threshold.

[0011] And determining a second threshold according to the load rate and the rated phase current on the high-voltage side of the main transformer includes: determining the product of the load rate and the rated phase current as a second product; and determining the product between a third coefficient and the second product as the second threshold.

[0012] Judging whether to execute the three-phase inconsistency protection of the high-voltage circuit breaker according to the current protection criterion and at least one corresponding voltage protection criterion as described above includes: determining to execute the three-phase inconsistency protection of the high-voltage circuit breaker when the current protection criterion includes turning on the three-phase inconsistency protection of the high-voltage circuit breaker and at least one corresponding voltage protection criterion includes turning on the three-phase inconsistency protection of the high-voltage circuit breaker.

[0013] In a second aspect, an embodiment of the present application further provides a three-phase inconsistency protection system for a high-voltage circuit breaker in a substation, including: a computer-readable storage medium and a processor; wherein, a computer program capable of running on the processor is stored in the computer-readable storage medium, and when the computer program is executed by the processor, the steps of the method described above are implemented.

[0014] The present invention has the following beneficial effects compared with the prior art:

[0015] The present invention first proposes to improve the sensitivity of zero-sequence and negative-sequence current protection by combining the real-time load rate of the transformer, and first proposes a voltage protection method based on the Dice similarity, which has better sensitivity and robustness than the traditional similarity algorithm. Thus, the performance of the three-phase inconsistency protection and testing technology of the high-voltage side circuit breaker in the substation is systematically improved. Description of the Drawings

[0016] Figure 1 The flowchart of a three-phase inconsistency protection method for a high-voltage circuit breaker in a substation provided by an embodiment of the present application is shown Figure 1 ;

[0017] Figure 2 The flowchart of a three-phase inconsistency protection method for a high-voltage circuit breaker in a substation provided by an embodiment of the present application is shown Figure 2 ;

[0018] Figure 3 The logic diagram of a three-phase inconsistency protection method for a high-voltage circuit breaker in a substation provided by an embodiment of the present application is shown;

[0019] Figure 4 The figure shows the test result schematic diagram of a three-phase inconsistency protection method for a high-voltage circuit breaker in a substation provided by an embodiment of the present application. Figure 1 ;

[0020] Figure 5 The figure shows the test result schematic diagram of a three-phase inconsistency protection system for a high-voltage circuit breaker in a substation provided by an embodiment of the present application. Figure 2 ;

[0021] Figure 6 The figure shows a schematic block diagram of a three-phase inconsistency protection system for a high-voltage circuit breaker in a substation provided by an embodiment of the present application. Specific embodiments

[0022] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0023] See Figure 1 , which shows a schematic flow chart of a three-phase inconsistency protection method for a high-voltage circuit breaker in a substation provided by an embodiment of the present application. Specifically, the protection method may include:

[0024] Step 101: Determine the load rate of the main transformer of the substation; constitute a current protection criterion for the three-phase inconsistency protection of the high-voltage circuit breaker according to the load rate;

[0025] Step 102: Determine the Dice similarity between the voltages at both ends of the high-voltage circuit breaker corresponding to each phase; constitute a voltage protection criterion for the three-phase inconsistency protection of the high-voltage circuit breaker according to the Dice similarity;

[0026] Step 103: Determine whether to execute the three-phase inconsistency protection of the high-voltage circuit breaker according to the current protection criterion and at least one corresponding voltage protection criterion.

[0027] Among them, for determining the load rate of the main transformer of the substation in step 101, it may include: determining the apparent power and rated capacity of the main transformer; determining the load rate according to the apparent power and the rated capacity, where the load rate is the apparent power divided by the rated capacity.

[0028] It should be noted that the apparent power of the main transformer of the substation is the real-time apparent power of the main transformer of the substation. The load rate may also be different at different times. The load rate may be the real-time apparent power divided by the rated capacity of the main transformer.

[0029] In some embodiments, for the current protection criterion of the three-phase inconsistency protection of the high-voltage circuit breaker formed according to the load rate in step 101, as Figure 2 shown, it may include:

[0030] Step 201: Determine a first threshold and a second threshold according to the load rate and the rated phase current on the high-voltage side of the main transformer;

[0031] Step 202: Obtain the three-phase currents on the high-voltage side of the main transformer of the substation, and obtain the zero-sequence current and the negative-sequence current according to the three-phase currents;

[0032] Step 203: Determine the zero-sequence current criterion according to the zero-sequence current and the first threshold; and determine the negative-sequence current criterion according to the negative-sequence current and the second threshold.

[0033] Among them, for determining the first threshold according to the load rate and the rated phase current on the high-voltage side of the main transformer in step 201, it may include: determining the product between the load rate and the rated phase current as a second product; and determining the product between the second coefficient and the second product as the first threshold;

[0034] And for determining the second threshold according to the load rate and the rated phase current on the high-voltage side of the main transformer, it may include: determining the product of the load rate and the rated phase current as a second product; and determining the product between the third coefficient and the second product as the second threshold.

[0035] For step 202, obtain the three-phase currents on the high-voltage side of the main transformer of the substation, and then obtain the zero-sequence current and the negative-sequence current through conversion according to the three-phase currents.

[0036] In some embodiments, for determining the zero-sequence current criterion according to the zero-sequence current and the first threshold in step 203, it may include: determining the product between the first coefficient and the zero-sequence current as a first product; obtaining the zero-sequence current criterion according to the first product and the first threshold; where, when the first product is greater than or equal to the first threshold, obtaining the zero-sequence current criterion includes turning on the three-phase inconsistency protection of the high-voltage circuit breaker.

[0037] In some embodiments, for determining the negative-sequence current criterion according to the negative-sequence current and the second threshold in step 203, it may include: comparing the current value of the negative-sequence current with the second threshold to obtain the negative-sequence current criterion; wherein, when the current value of the negative-sequence current is greater than or equal to the second threshold, obtaining the negative-sequence current criterion includes turning on the three-phase inconsistency protection of the high-voltage circuit breaker.

[0038] The process described above calculates the three-phase inconsistency current criteria for zero-sequence and negative-sequence according to the load factor. Specifically, the three-phase inconsistency current criteria may include a negative-sequence current judgment and / or a zero-sequence current criterion. The specific criteria can be seen in the following formula (1):

[0039]

[0040] Among them, the value of the first coefficient in formula (1) can be 3; I 0.op is the zero-sequence current; I 2.op is the negative-sequence current; μ is the load factor; In is the rated phase current; 3I 0.op is the first product; μI n is the second product; the value range of the second coefficient in formula (1) can be 0.2 to 0.5. The value of the third coefficient in formula (1) can be 0.1.

[0041] In the present application, for determining the zero-sequence current criterion according to the zero-sequence current and the first threshold in step 203, it may be to compare the first product and the first threshold. When the first product is greater than or equal to the first threshold, obtaining the zero-sequence current criterion includes turning on the three-phase inconsistency protection of the high-voltage circuit breaker. That is, when 3I 0.op ≥(0.2 - 0.5)μI n obtaining the zero-sequence current criterion includes turning on the three-phase inconsistency protection of the high-voltage circuit breaker.

[0042] In the present application, for determining the negative-sequence current criterion according to the negative-sequence current and the second threshold in step 203, it may include: comparing the current value of the negative-sequence current with the second threshold, and when the current value of the negative-sequence current is greater than or equal to the second threshold, obtaining the negative-sequence current criterion includes turning on the three-phase inconsistency protection of the high-voltage circuit breaker. That is, when I 2.op ≥0.1μI n obtaining the negative-sequence current criterion includes turning on the three-phase inconsistency protection of the high-voltage circuit breaker.

[0043] In some embodiments, for determining the Dice similarity between the voltages at both ends of the corresponding high-voltage circuit breaker for each phase in step 102, the Dice similarity can be calculated according to the following formula (2):

[0044]

[0045] Wherein, U1 and U2 are the voltages at both ends of the high-voltage circuit breaker; N is the number of groups of voltages at both ends of the high-voltage circuit breaker, and the voltages U1 and U2 at both ends of the high-voltage circuit breaker sampled simultaneously are one group. R D is the Dice similarity.

[0046] In some embodiments, for determining the voltage protection criterion according to the Dice similarity and the set similarity in step 203, it may include: comparing the Dice similarity with the set similarity to obtain the voltage protection criterion; wherein, when the Dice similarity is less than or equal to the set similarity, obtaining the voltage protection criterion includes turning on the three-phase inconsistency protection of the high-voltage circuit breaker.

[0047] Specifically, the three-phase inconsistency voltage criterion of the high-voltage circuit breaker constructed based on the Dice similarity can refer to formula (3):

[0048] R D ≤R set (3)

[0049] Wherein, R D is the Dice similarity; R set is the set similarity, and in one embodiment, the set similarity can be set to 0.7.

[0050] In some embodiments, determining whether to execute the three-phase inconsistency protection of the high-voltage circuit breaker according to the current protection criterion and at least one corresponding voltage protection criterion includes:

[0051] When the current protection criterion includes turning on the three-phase inconsistency protection of the high-voltage circuit breaker and at least one corresponding voltage protection criterion includes turning on the three-phase inconsistency protection of the high-voltage circuit breaker, it is determined to execute the three-phase inconsistency protection of the high-voltage circuit breaker.

[0052] That is to say, the current protection criterion based on the load rate and the voltage protection criterion based on the Dice similarity form an AND logic to determine whether the three-phase inconsistency protection of the substation high-voltage circuit breaker operates (that is, whether to execute the three-phase inconsistency protection of the high-voltage circuit breaker). Since the high-voltage circuit breaker of the substation is three-phase, therefore, when actually determining the three-phase inconsistency protection, as long as at least one voltage protection criterion corresponding to the high-voltage circuit breaker phase includes turning on the three-phase inconsistency protection; and the current protection criterion (including the zero-sequence current criterion and / or the negative-sequence current criterion) includes turning on the three-phase inconsistency protection, it is determined to execute the three-phase inconsistency protection of the high-voltage circuit breaker.

[0053] For understanding this application, as Figure 3As shown, it shows a logic diagram of the three-phase inconsistency protection of the high-voltage circuit breaker in the substation provided by the embodiments of the present application. The load rate adaptive current protection criterion and the voltage protection criterion based on Dice similarity form an AND logic to determine whether to execute the three-phase inconsistency protection of the substation circuit breaker. During the protection test, the circuit breaker switch control operation is carried out through the main and auxiliary integrated monitoring host. During this period, single-phase / two-phase disconnection of the primary system at different positions is simulated to check whether the protection method operates correctly and whether relevant operation instructions and alarms are sent correctly. Specifically, the protection test requires a live simulation of the operation of the primary system and a panoramic simulation of the interaction of the secondary system.

[0054] The following tests the proposed protection method through simulation verification:

[0055] Build a primary simulation model of the substation based on the electromagnetic transient simulation software, and the three-phase inconsistency fault of the high-voltage side circuit breaker of the substation main transformer can be set.

[0056] For the load rate adaptive current protection criterion, single-phase disconnection of the circuit breaker is set respectively at different transformer load rates, and the action values 3I 0.op and I 2.op , threshold values (0.2 - 0.5) μI n and 0.1 μI n are obtained as shown in Figure 4 and Figure 5 . It can be found that the action values of the negative sequence and zero sequence three-phase inconsistency current criteria decrease with the decrease of the transformer load rate, and the proposed load rate adaptive criterion can reduce the threshold value accordingly to ensure the sensitivity of the proposed protection.

[0057] For the voltage protection criterion based on Dice similarity, scenarios of single-phase grounding outside the substation, two-phase short circuit outside the substation, single-phase disconnection of the circuit breaker inside the substation, and two-phase disconnection of the circuit breaker are set for testing respectively. The Dice similarity calculation results are shown in Table 1. Table 1 shows the Dice similarity calculation results under two different fault types. It can be found that the proposed voltage protection criterion based on Dice similarity can accurately identify three-phase inconsistency faults and is not affected by other types of external faults. The effectiveness of the proposed protection method is verified.

[0058] Table 1

[0059] Fault type Single-phase disconnection Two-phase disconnection Dice similarity calculation result -0.17 0.14

[0060] The embodiments of the present application also provide a three-phase inconsistency protection system for the high-voltage circuit breaker in the substation, including: a computer-readable storage medium and a processor; wherein, the computer-readable storage medium stores a computer program that can run on the processor, and when the computer program is executed by the processor, it realizes the steps of the method described in any one of the above.

[0061] It should be noted that the three-phase inconsistency protection system for high-voltage circuit breakers in a substation provided in the embodiments of the present application has the same technical features as the three-phase inconsistency protection method for high-voltage circuit breakers in a substation provided above. Therefore, the nouns that appear here and how to implement them specifically have been described in detail above. For understanding, reference can be made to the content described above and will not be elaborated here.

[0062] The embodiments of the present application also provide a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method described in any of the above items are implemented.

[0063] Figure 6 It is a schematic block diagram of a three-phase inconsistency protection system 700 for a high-voltage circuit breaker in a substation according to an embodiment of the present application. Figure 6 The three-phase inconsistency protection system 700 for the high-voltage circuit breaker in the substation shown includes a memory 701, a processor 702, a communication interface 703, and a bus 704. Among them, the memory 701, the processor 702, and the communication interface 703 are communicatively connected to each other through the bus 704.

[0064] The memory 701 can be a graphics processing unit (GPU) storage system, a read-only memory (ROM), a static storage device, a dynamic storage device, and / or a random access memory (RAM). The memory 701 can store a program. When the program stored in the memory 701 is executed by the processor 702, the processor 702 is used to execute the various steps of the method of the embodiments of the present application. For example, it can execute the various steps of the embodiments shown above. Figure 1 and other embodiments shown.

[0065] The processor 702 can adopt a graphics processing unit (GPU), a neural network processing unit (NPU), a microprocessor, an application-specific integrated circuit (ASIC), and / or one or more integrated circuits to execute relevant programs to implement the method of the method embodiments of the present application.

[0066] The processor 702 can also be an integrated circuit chip with the ability to process signals. In the implementation process, the various steps of the method of the embodiments of the present application can be completed by the integrated logic circuit in the hardware of the processor 702 and / or instructions in the form of software.

[0067] The above-mentioned processor 702 may also be a general-purpose processor, a digital signal processor (DSP), an application specific integrated circuit, a field programmable gate array (FPGA), and / or other programmable logic devices, discrete gate and / or transistor logic devices, discrete hardware components. It can implement and / or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor may be a microprocessor, and / or this processor may also be any conventional processor, etc.

[0068] The steps of the method disclosed in combination with the embodiments of the present application may be directly embodied as being executed and completed by a hardware decoding processor, and / or may be executed and completed by a combination of hardware and software modules in the decoding processor. The software module may be located in a mature storage medium in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, and / or an electrically erasable programmable memory, a register, etc. This storage medium is located in the memory 701, and the processor 702 reads the information in the memory 701 and combines its hardware to complete the functions required to be executed by the units included in each device in the embodiments of the present application, and / or executes the methods of the method embodiments in the present application. For example, it may execute Figure 1 each step / function of the embodiments shown, etc.

[0069] The communication interface 703 may use, but is not limited to, transceiver devices such as transceivers to implement the communication between the three-phase inconsistency protection system of the high-voltage circuit breaker in the substation and other devices or communication networks.

[0070] The bus 704 may include a path for transmitting information between various components (for example, the memory 701, the processor 702, the communication interface 703) of the three-phase inconsistency protection system of the high-voltage circuit breaker in the substation.

[0071] It should be understood that the three-phase inconsistency protection system of the high-voltage circuit breaker in the substation shown in the embodiments of the present application may be a processor or a chip for executing the methods described in the embodiments of the present application.

[0072] It should be understood that in the embodiments of the present application, this processor may be a graphics processing unit (GPU), and this processor may also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), and / or other programmable logic devices, discrete component gate circuits, and / or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor, and / or this processor may also be any conventional processor, etc.

[0073] It should be understood that in the embodiments of the present application, "B corresponding to A" means that B is associated with A, and B can be determined according to A. However, it should also be understood that determining B according to A does not mean determining B only according to A, and B can also be determined according to A and / or other information.

[0074] It should be understood that the term "and / or" in this article is only a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the associated objects before and after.

[0075] It should be understood that in various embodiments of the present application, the magnitudes of the serial numbers of the above processes do not mean the order of execution. The order of execution of each process should be determined according to its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0076] In several embodiments provided in the present application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the units is only a logical function division, and there can be other division methods in actual implementation. For example, multiple units or components can be combined and / or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection to each other can be through some interfaces, and the indirect coupling or communication connection of the device or unit can be in an electrical, mechanical, or other form.

[0077] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place and / or can be distributed to multiple network units. Some and / or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0078] In addition, the functional units in various embodiments of the present application can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit.

[0079] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware, and / or any combination thereof. When implemented using software, it can be implemented in the form of a computer program product in whole or in part. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, and / or other programmable devices. The computer instructions can be stored in a computer-readable storage medium and / or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center in a wired manner (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wirelessly (such as infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be read by a computer and / or a data storage device such as a server or data center that includes one or more integrated available media. The available medium can be a magnetic medium (such as a floppy disk, hard disk, magnetic tape), an optical medium (such as a digital versatile disc (DVD)), and / or a semiconductor medium (such as a solid-state drive (SSD)), etc.

[0080] The foregoing are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, etc. made within the spirit and principles of the present application shall be included within the protection scope of the present application.

Claims

1. A three-phase inconsistency protection method for high-voltage circuit breakers in a substation, characterized in that, Including: Determine the load rate of the main transformer of the substation; constitute the current protection criterion for the three-phase inconsistency protection of the high-voltage circuit breaker according to the load rate; Determine the Dice similarity between the voltages at both ends of the high-voltage circuit breaker corresponding to each phase; constitute the voltage protection criterion for the three-phase inconsistency protection of the high-voltage circuit breaker according to the Dice similarity; Judge whether to execute the three-phase inconsistency protection of the high-voltage circuit breaker according to the current protection criterion and at least one corresponding voltage protection criterion.

2. The method according to claim 1, wherein The determining the load rate of the main transformer of the substation includes: Determine the apparent power and rated capacity of the main transformer; Determine the load rate according to the apparent power and the rated capacity, where the load rate is the apparent power divided by the rated capacity.

3. The method according to claim 1, characterized in that, The current protection criterion includes a negative-sequence current criterion and / or a zero-sequence current criterion; the constituting the current protection criterion for the three-phase inconsistency protection of the high-voltage circuit breaker according to the load rate includes: Determine a first threshold and a second threshold according to the load rate and the rated phase current on the high-voltage side of the main transformer; Obtain the three-phase currents on the high-voltage side of the main transformer of the substation, and obtain the zero-sequence current and the negative-sequence current according to the three-phase currents; Determine the zero-sequence current criterion according to the zero-sequence current and the first threshold; and determine the negative-sequence current criterion according to the negative-sequence current and the second threshold.

4. The method according to claim 3, wherein The determining the zero-sequence current criterion according to the zero-sequence current and the first threshold includes: Determine the product of a first coefficient and the zero-sequence current as a first product; Obtain the zero-sequence current criterion according to the first product and the first threshold; where, when the first product is greater than or equal to the first threshold, obtaining the zero-sequence current criterion includes turning on the three-phase inconsistency protection of the high-voltage circuit breaker.

5. The method according to claim 3, characterized in that, The determining the negative-sequence current criterion according to the negative-sequence current and the second threshold includes: Compare the current value of the negative-sequence current with the second threshold to obtain the negative-sequence current criterion; Where, when the current value of the negative-sequence current is greater than or equal to the second threshold, obtaining the negative-sequence current criterion includes turning on the three-phase inconsistency protection of the high-voltage circuit breaker.

6. The method according to claim 1, characterized in that The determining the voltage protection criterion according to the Dice similarity and a set similarity includes: Compare the Dice similarity with the set similarity to obtain the voltage protection criterion; Where, when the Dice similarity is less than or equal to the set similarity, obtaining the voltage protection criterion includes turning on the three-phase inconsistency protection of the high-voltage circuit breaker.

7. The method according to claim 3, wherein The determining the first threshold according to the load rate and the rated phase current on the high-voltage side of the main transformer includes: determining the product of the load rate and the rated phase current as a second product; and determining the product of a second coefficient and the second product as the first threshold; The determining the second threshold according to the load rate and the rated phase current on the high-voltage side of the main transformer includes: determining the product of the load rate and the rated phase current as a second product; and determining the product of a third coefficient and the second product as the second threshold.

8. The method according to claim 1, wherein Determining whether to execute the three-phase inconsistency protection of the high-voltage circuit breaker according to the current protection criterion and at least one corresponding voltage protection criterion includes: When the current protection criterion includes enabling the three-phase inconsistency protection of the high-voltage circuit breaker and at least one corresponding voltage protection criterion includes enabling the three-phase inconsistency protection of the high-voltage circuit breaker, it is determined to execute the three-phase inconsistency protection of the high-voltage circuit breaker.

9. A three-phase inconsistency protection system for a high-voltage circuit breaker in a substation, characterized in that, Including: A computer-readable storage medium and a processor; wherein, a computer program capable of running on the processor is stored in the computer-readable storage medium, and when the computer program is executed by the processor, the steps of the method according to any one of claims 1 to 9 are implemented.

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