Transition resistance-tolerant grounding distance protection method and system

Abstract

The invention discloses a grounding distance protection method and system for a tolerant transition resistor, and relates to the technical field of power system research, and the method comprises the steps: solving a transition resistor, a fault resistor and a reactance through employing the sampling information of voltage and current at a protection installation part; establishing a relation between the transition resistance and the fault resistance and the reactance according to a solving result; based on the established relation, the fault resistance and reactance are adaptively adjusted through the transition resistance; and determining a protection action behavior by using the adjusted fault resistance and reactance. When a single-phase net multi-fault resistor grounding fault occurs in an AC power transmission line with new energy transmission, the influence of transition resistance on the measured impedance value is effectively reduced, the problem of refusal to operate caused by the transition resistance fault is avoided, and the accuracy and sensitivity of an intra-region fault judgment result during the single-phase grounding fault are greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a ground distance protection method and system capable of withstanding transition resistance. Background Art

[0002] Compared with current protection and voltage protection, the protection range and sensitivity of distance protection are less affected by changes in system operation mode. It can quickly and selectively cut off faults in complex networks. It has been widely used in high-voltage transmission lines and is the most important backup protection in transmission lines.

[0003] Single-phase grounding fault is the most common type of fault in the operation of transmission lines, accounting for more than 90% of all types of faults, and is usually accompanied by transition resistance. In the existing technology, backup protection usually uses distance protection to identify single-phase grounding faults in AC transmission lines. As the power system is rapidly developing towards a high proportion of renewable energy and a high proportion of power electronic equipment, the weak feedback characteristics of new energy have magnified the impact of transition resistance. After a single-phase grounding fault occurs in the AC transmission line of new energy transmission, due to the existence of transition resistance, the distance protection measurement impedance will have errors. At this time, the measured impedance cannot correctly reflect the fault location, resulting in the failure of traditional distance protection to operate correctly. Summary of the invention

[0004] In view of the above existing problems, the present invention is proposed.

[0005] Therefore, the present invention provides a ground distance protection method and system that are tolerant to transition resistance. When judging a ground fault in an AC transmission line, the influence of transition resistance on the measured impedance is reduced, thereby greatly improving the accuracy of the fault judgment results in the single-phase ground fault zone and ensuring the correct operation of the distance protection.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] In a first aspect, the present invention provides a ground distance protection method that tolerates transition resistance, including: using sampling information of voltage and current at the protection installation location to solve the transition resistance, fault resistance and reactance; establishing a relationship between the transition resistance and the fault resistance and reactance based on the solution result; based on the established relationship, adaptively adjusting the fault resistance and reactance through the transition resistance; and determining the protection action behavior using the adjusted fault resistance and reactance.

[0008] As a preferred solution of the transition resistance tolerant ground distance protection method of the present invention, the method of solving the transition resistance by using the sampling information of the voltage and current at the protection installation location includes:

[0009] The fault location is solved by using a time domain differential equation, and the zero-sequence current measured at the protection installation is used instead of the fault point current to construct a fault distance measurement equation. Based on the fault distance measurement equation, the transition resistance is solved. The formula is expressed as follows:

[0010]

[0011] Among them, u m (t), i m (t) are the instantaneous values ​​of the fault phase voltage and current at the protection installation location, K r is the resistance zero-sequence compensation coefficient, i m0 (t) is the instantaneous value of zero-sequence current, K l is the zero-sequence inductance compensation coefficient, r1 and l1 are the positive-sequence resistance and inductance per unit length of the line, respectively, R' F is the equivalent transition resistance.

[0012] As a preferred solution of the ground distance protection method withstanding transition resistance described in the present invention, the fault resistance and reactance are solved by using the sampling information of the voltage and current at the protection installation location:

[0013]

[0014] in, are respectively the compound calculation values ​​of the fault phase voltage and current at the protection installation location, K z is the zero-sequence compensation coefficient, is the zero-sequence current compound calculation value, R m , X m are the fault resistance and reactance respectively.

[0015] As a preferred solution of the transition resistance tolerant ground distance protection method of the present invention, the relationship between the transition resistance and the fault resistance and the reactance is established according to the solution result:

[0016]

[0017] Among them, Z m is the ground distance protection measurement impedance, k is and The amplitude ratio of θ is Ahead of the times Angle, is the current passing through the transition resistor.

[0018] As a preferred solution of the transition resistance tolerant ground distance protection method of the present invention, wherein: based on the established connection, adaptively adjusting the fault resistance and reactance through the transition resistance includes:

[0019] If 0<Rm ≤R set , then no adjustment is required, protecting direct action;

[0020] Among them, R set Set the value for the protection range resistance.

[0021] As a preferred solution of the transition resistance tolerant ground distance protection method of the present invention, wherein: based on the established connection, the adaptive adjustment of the fault resistance and reactance through the transition resistance also includes:

[0022] If R m >R set &X m <X set , then the fault resistance and reactance need to be adjusted, and the adjustment process is:

[0023]

[0024] If R m >R set &X m >X set , then the fault resistance and reactance need to be adjusted, and the adjustment process is:

[0025]

[0026] Among them, R set , X set R' is the protection range resistance setting value and reactance setting value. m1 , X′ m1 For R m >R set &X m <X set Fault resistance and reactance adjusted under the conditions, R′ m2 , X′ m2 For R m >R set &X m >X set Fault resistance and reactance adjusted under the following conditions.

[0027] As a preferred solution of the transition resistance tolerant ground distance protection method of the present invention, the method of determining the protection action behavior by using the adjusted fault resistance and reactance includes:

[0028] By using the adjusted fault resistance and reactance combined with the conventional quadrilateral distance protection action area, it is determined whether the adjusted fault resistance and reactance are within the action range, and then whether the protection is activated.

[0029] In a second aspect, the present invention provides a ground distance protection system capable of withstanding transition resistance, comprising:

[0030] A data solving unit is used to solve the transition resistance, fault resistance and reactance by using the sampling information of the voltage and current at the protection installation location;

[0031] A connection building unit, used for establishing a connection between the transition resistance and the fault resistance and reactance according to the solution result;

[0032] an adaptive adjustment unit, configured to adaptively adjust the fault resistance and reactance through the transition resistance based on the established connection;

[0033] The action behavior determination unit is used to determine the protection action behavior by using the adjusted fault resistance and reactance.

[0034] In a third aspect, the present invention provides a computing device, comprising:

[0035] Memory and processor;

[0036] The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the computer-executable instructions are executed by the processor, the steps of the method are implemented.

[0037] In a fourth aspect, the present invention provides a computer-readable storage medium storing computer-executable instructions, which implement the steps of the method when executed by a processor.

[0038] Compared with the prior art, the beneficial effects of the present invention are as follows: when a single-phase grounding fault occurs through a transition resistor in an AC transmission line supplied by renewable energy, the present invention effectively reduces the influence of the transition resistance on the measured impedance value, avoids the refusal to operate problem caused by the transition resistance fault, and greatly improves the accuracy and sensitivity of the fault judgment results in the single-phase grounding fault time zone. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0040] Figure 1 This is an overall flow chart of a transition resistance tolerant ground distance protection method according to an embodiment of the present invention;

[0041] Figure 2 A line concentrated parameter model diagram of a ground distance protection method withstanding transition resistance according to an embodiment of the present invention;

[0042] Figure 3 A schematic diagram of a conventional quadrilateral distance protection action area of ​​a ground distance protection method with tolerance to transition resistance according to an embodiment of the present invention;

[0043] Figure 4 A schematic diagram of a simulation system for a ground distance protection method capable of withstanding transition resistance according to an embodiment of the present invention;

[0044] Figure 5 This is a diagram of impedance trajectory measured at point F1 through a 1.21Ω transition resistor in a transition resistance-tolerant ground distance protection method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0046] Example 1

[0047] Reference Figure 1 to Figure 3 As an embodiment of the present invention, a ground distance protection method tolerant to transition resistance is provided, which reduces the influence of transition resistance on the measured impedance when judging the ground fault of AC transmission line, thereby greatly improving the accuracy of fault judgment results in the single-phase ground fault zone and ensuring the correct operation of distance protection. Figure 1 The specific steps shown include:

[0048] S100: Using the sampling information of voltage and current at the protection installation, the transition resistance, fault resistance and reactance are solved;

[0049] In the embodiment of the present application, for a single-phase metallic ground fault, based on Figure 2 The line concentrated parameter model diagram shown above uses the time domain differential equation to solve the fault location:

[0050]

[0051] Among them, u mA (t), i mA (t) are the instantaneous values ​​of the A-phase bus voltage and current, K r =(r0-r1) / 3r1 is the resistance zero sequence compensation coefficient, i m0 (t) is the instantaneous value of zero-sequence current, K l=(l0-l1) / 3l1 is the zero-sequence inductance compensation coefficient, r1 and l1 are the positive-sequence resistance and inductance per unit length of the line, respectively, i F (t) is the instantaneous value of the current at the fault point, R F is the fault resistance;

[0052] It should be noted that a single-phase metallic ground fault refers to a situation in which a phase conductor is short-circuited to the earth directly or through a very small impedance in a transmission or distribution system. This type of fault is one of the common power system faults, especially in power grids where the neutral point is not directly grounded or grounded through an arc suppression coil. When a single-phase metallic ground fault occurs, the current at the fault point can be very large, which may lead to the following consequences: ① Damage to electrical equipment: Excessive fault current may cause equipment to overheat or even burn; ② Power supply interruption: The fault may affect the stability of the entire system, causing a power outage; ③ Relay protection action: In order to prevent a wider range of impacts, the relay protection device will detect the abnormal current and cut off the power supply to isolate the fault area. In modern power grid management, advanced monitoring technology and smart grid technology are used to quickly locate the fault point and restore power supply as soon as possible. These technologies include but are not limited to fault recorders, SCADA systems (data acquisition and monitoring systems), and real-time monitoring and fault diagnosis functions in smart grids.

[0053] Furthermore, the zero-sequence current measured at the protection installation is used instead of the fault point current to construct the fault location equation. Based on the fault location equation, the transition resistance is solved. The formula is expressed as:

[0054]

[0055] Among them, u m (t), i m (t) are the instantaneous values ​​of the fault phase voltage and current at the protection installation location, K r =(r0-r1) / 3r1 is the resistance zero sequence compensation coefficient, i m0 (t) is the instantaneous value of zero-sequence current, K l =(l0-l1) / 3l1 is the zero-sequence compensation coefficient of inductance, r1 and l1 are the positive-sequence resistance and inductance per unit length of the line, respectively, R' F is the equivalent transition resistance.

[0056] In the embodiment of the present application, the sampling information of the voltage and current at the protection installation is used to solve the fault resistance and reactance as follows:

[0057]

[0058] in, are respectively the compound calculation values ​​of the fault phase voltage and current at the protection installation location, K z=(z0-z1) / 3z1 is the zero sequence compensation coefficient, is the zero-sequence current compound calculation value, R m , X m are the fault resistance and reactance respectively.

[0059] S200: establishing the relationship between the transition resistance and the fault resistance and the reactance according to the solution result;

[0060] In the embodiment of the present application, the calculation formula of the ground distance protection measurement impedance is:

[0061]

[0062] Among them, Z m Measuring impedance for ground distance protection, are respectively the compound calculation values ​​of the fault phase voltage and current at the protection installation location, K z =(z0-z1) / 3z1 is the zero sequence compensation coefficient, is the zero-sequence current compound calculation value, is the current through the transition resistor, Z k and Z add are the fault impedance and transition resistance additional impedance respectively, R F is the transition resistance value;

[0063] Among them, the calculation of the additional impedance of the transition resistance is specifically:

[0064]

[0065] From the above, the calculation of equivalent transition resistance can be obtained as:

[0066]

[0067] Furthermore, the calculation formula of the transition resistance additional impedance is substituted into the calculation formula of the equivalent transition resistance to obtain:

[0068]

[0069] Among them, k is and The amplitude ratio of θ is Ahead of the times The angle is related to the zero-sequence impedance angle on both sides of the fault and generally does not exceed 12°.

[0070] Furthermore, based on the above content, the relationship between transition resistance, fault resistance and reactance is established as follows:

[0071]

[0072] Among them, Zm is the complex impedance composed of fault resistance and reactance, k is and The amplitude ratio of θ is Ahead of the times Angle, is the current passing through the transition resistor.

[0073] S300: Based on the established connection, adaptively adjust the fault resistance and reactance through the transition resistance;

[0074] In the embodiment of the present application, if 0<R m ≤R set , then no adjustment is required, the protection acts directly, where R set Set the value for the protection range resistance;

[0075] It should be noted that if 0<R m ≤R set , according to kcosθ·R′ F >0,ksinθ·R′ F >0, we can get R k <R m ≤R set , then no adjustment is required, protecting direct action.

[0076] In the embodiment of the present application, if R m >R set &X m <X set , then the fault resistance and reactance need to be adjusted, and the adjustment process is:

[0077]

[0078] If R m >R set &X m >X set , then the fault resistance and reactance need to be adjusted, and the adjustment process is:

[0079]

[0080] Among them, R set , X set R' is the protection range resistance setting value and reactance setting value. m1 , X′ m1 For R m >R set &X m <X set Fault resistance and reactance adjusted under the conditions, R′ m2 , X′ m2 For R m>R set &X m >X set Fault resistance and reactance adjusted under the following conditions.

[0081] S400: Determine protection action behavior using the adjusted fault resistance and reactance;

[0082] In the embodiment of the present application, the adjusted fault resistance and reactance are combined with the conventional quadrilateral distance protection action area to determine whether the adjusted fault resistance and reactance are within the action range, and then determine whether the protection is activated;

[0083] It should be noted that the schematic diagram of the conventional quadrilateral distance protection action area is as follows Figure 3 As shown, after the protection is activated, the measured impedance after adjustment is used to combine with the conventional quadrilateral distance protection action area to determine whether the protection is activated, where Z set The set impedance is 80%, which is generally 80% of the total line reactance.

[0084] From the above, it can be seen that when a single-phase grounding fault occurs in the AC transmission line sent by renewable energy through a transition resistor, the present invention effectively reduces the influence of the transition resistance on the measured impedance value, avoids the refusal to operate problem caused by the transition resistance fault, and greatly improves the accuracy and sensitivity of the fault judgment result in the single-phase grounding fault time zone.

[0085] The above is a schematic scheme of a ground distance protection method tolerant to transition resistance in this embodiment. It should be noted that the technical scheme of the ground distance protection system tolerant to transition resistance and the technical scheme of the ground distance protection method tolerant to transition resistance belong to the same concept, and the details not described in detail in the technical scheme of the ground distance protection system tolerant to transition resistance in this embodiment can be referred to the description of the technical scheme of the ground distance protection method tolerant to transition resistance.

[0086] This embodiment also provides a ground distance protection system that tolerates transition resistance, including a data solving unit, a connection building unit, an adaptive adjustment unit, and an action behavior determination unit;

[0087] Specifically, the data solving unit is used to solve the transition resistance, fault resistance and reactance by using the sampling information of the voltage and current at the protection installation location;

[0088] Specifically, the connection construction unit is used to establish the connection between the transition resistance and the fault resistance and the reactance according to the solution result;

[0089] Specifically, the adaptive adjustment unit is used to adaptively adjust the fault resistance and reactance through the transition resistance based on the established connection;

[0090] Specifically, the action behavior determination unit is used to determine the protection action behavior using the adjusted fault resistance and reactance.

[0091] The above-mentioned unit modules may be embedded in or independent of a processor in a computer device in the form of hardware, or may be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to the above-mentioned modules.

[0092] The present embodiment also provides a computing device, which includes a processor, a memory, a communication interface, a display screen and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through WIFI, an operator network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a ground distance protection method that tolerates transition resistance is implemented. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covered on the display screen, or a button, a trackball or a touch pad set on the housing of the computer device, or an external keyboard, touch pad or mouse, etc.

[0093] This embodiment also provides a storage medium on which a computer program is stored. When the program is executed by a processor, the method proposed in the above embodiment is implemented.

[0094] The storage medium proposed in this embodiment and the method proposed in the above embodiment belong to the same inventive concept. The technical details not fully described in this embodiment can be referred to the above embodiment, and this embodiment has the same beneficial effects as the above embodiment.

[0095] Through the above description of the implementation methods, the technicians in the relevant field can clearly understand that the present invention can be implemented by means of software and necessary general hardware, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ReadOnly, Memory, ROM), random access memory (RandomAccess Memory, RAM), flash memory (FLASH), hard disk or optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform the methods of various embodiments of the present invention.

[0096] Example 2

[0097] Reference Figure 4 and Figure 5 Based on the previous embodiment, this embodiment provides an application example of a ground distance protection method and system that can tolerate transition resistance, in order to verify and illustrate the technical effects used in this method.

[0098] This embodiment is based on the PSCAD / EMTDC electromagnetic transient simulation platform. Figure 4 The test system simulation model shown verifies the proposed ground distance protection scheme withstanding transition resistance.

[0099] The line length is 30km, the positive sequence impedance per kilometer is 0.0705+0.4j, the zero sequence impedance is 0.4+1.2j, the protection range is 80% of the total line length, and F1 is the A phase fault at the midpoint of the line through a transition resistor.

[0100] Table 1: Comparison table of distance protection action conditions.

[0101] Fault location Transition voltage group / Ω Traditional distance protection action Action status of this plan F1 0 action action F1 1.21 No action action F1 6.5 No action action F1 12.1 No action action

[0102] Taking the A phase of point F1 through a 1.21Ω transition resistor as an example, the impedance trajectory of conventional distance protection and distance protection of this scheme is measured Figure 5 shown.

[0103] The comprehensive simulation results show that the traditional quadrilateral impedance characteristic protection and the scheme proposed in this embodiment can operate correctly in the case of metallic faults. When the transition resistance of the line impedance is 0.1pu, the measurement trajectory of the traditional distance protection is outside the protection action area, and the protection refuses to operate. After adjustment by the method provided in this embodiment, the measured impedance falls within the action area, and the distance protection operates correctly.

[0104] From the above, it can be seen that when a single-phase grounding fault occurs in the AC transmission line sent by renewable energy through a transition resistor, the present invention effectively reduces the influence of the transition resistance on the measured impedance value, avoids the refusal to operate problem caused by the transition resistance fault, and greatly improves the accuracy and sensitivity of the fault judgment result in the single-phase grounding fault time zone.

[0105] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

[0106] 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.

[0107] 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.

[0108] 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.

[0109] 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 The steps for the functions specified in one or more boxes.

[0110] 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.

[0111] 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 ground distance protection method tolerant to transition resistance, characterized in that: include: Using the sampling information of voltage and current at the protection installation, the transition resistance, fault resistance and reactance are solved; Establishing the relationship between the transition resistance and the fault resistance and reactance according to the solution result; Based on the established connection, adaptively adjusting the fault resistance and reactance through the transition resistance; The adjusted fault resistance and reactance are used to determine the protection action behavior.

2. The ground distance protection method withstanding transition resistance according to claim 1, characterized in that: The method of using the sampling information of the voltage and current at the protection installation location to solve the transition resistance includes: The fault location is solved by using a time domain differential equation, and the zero-sequence current measured at the protection installation is used instead of the fault point current to construct a fault distance measurement equation. Based on the fault distance measurement equation, the transition resistance is solved. The formula is expressed as follows: Among them, u m (t), i m (t) are the instantaneous values ​​of the fault phase voltage and current at the protection installation location, K r is the resistance zero-sequence compensation coefficient, i m0 (t) is the instantaneous value of zero-sequence current, K l is the zero-sequence inductance compensation coefficient, r1 and l1 are the positive-sequence resistance and inductance per unit length of the line, respectively, R' F is the equivalent transition resistance.

3. The ground distance protection method withstanding transition resistance according to claim 2, characterized in that: The sampling information of the voltage and current at the protection installation is used to solve the fault resistance and reactance as follows: in, are respectively the compound calculation values ​​of the fault phase voltage and current at the protection installation location, K z is the zero-sequence compensation coefficient, is the zero-sequence current compound calculation value, R m , X m are the fault resistance and reactance respectively.

4. The ground distance protection method withstanding transition resistance according to claim 3, characterized in that: The relationship between the transition resistance and the fault resistance and the reactance is established according to the solution result: Among them, Z m is the ground distance protection measurement impedance, k is and The amplitude ratio of θ is Ahead of the times Angle, is the current passing through the transition resistor.

5. The ground distance protection method withstanding transition resistance according to claim 4, characterized in that: The step of adaptively adjusting the fault resistance and reactance by the transition resistance based on the established connection includes: If 0<R m ≤R set , then no adjustment is required, protecting direct action; Among them, R set Set the value for the protection range resistance.

6. The ground distance protection method withstanding transition resistance according to claim 4, characterized in that: The method of adaptively adjusting the fault resistance and reactance through the transition resistance based on the established connection further includes: If R m >R set &X m <X set , then the fault resistance and reactance need to be adjusted, and the adjustment process is: If R m >R set &X m >X set , then the fault resistance and reactance need to be adjusted, and the adjustment process is: Among them, R set , X set R' is the protection range resistance setting value and reactance setting value. m1 , X′ m1 For R m >R set &X m <X set Fault resistance and reactance adjusted under the conditions, R′ m2 , X′ m2 For R m >R set &X m >X set Fault resistance and reactance adjusted under the following conditions.

7. The ground distance protection method withstanding transition resistance according to any one of claims 5 and 6, characterized in that: The method of determining the protection action behavior by using the adjusted fault resistance and reactance includes: The adjusted fault resistance and reactance are combined with the conventional quadrilateral distance protection action area to determine whether the adjusted fault resistance and reactance are within the action range, and then determine whether the protection is activated.

8. A system using the ground distance protection method withstanding transition resistance as claimed in any one of claims 1 to 7, characterized in that: include: A data solving unit is used to solve the transition resistance, fault resistance and reactance by using the sampling information of the voltage and current at the protection installation location; A connection building unit, used for establishing a connection between the transition resistance and the fault resistance and reactance according to the solution result; an adaptive adjustment unit, configured to adaptively adjust the fault resistance and reactance through the transition resistance based on the established connection; The action behavior determination unit is used to determine the protection action behavior by using the adjusted fault resistance and reactance.

9. An electronic device, comprising: Memory and processor; The memory is used to store computer executable instructions, and the processor is used to execute the computer executable instructions. When the computer executable instructions are executed by the processor, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having computer program instructions stored thereon, wherein the computer-executable instructions, when executed by a processor, implement the steps of the method according to any one of claims 1 to 7.

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