System and method for judging and isolating single-phase earth fault based on centralized FA of wireless communication master station

Abstract

The invention discloses a system for judging and isolating a single-phase earth fault based on a centralized FA of a wireless communication master station. The main points of the technical scheme are that the system comprises a transformer station zero sequence voltage transformer, a sequence characteristic wave injection device, a primary and secondary fusion vacuum circuit breaker feeder terminal (FTU), a primary and secondary fusion vacuum circuit breaker, a fault indicator, a wireless communication system and a master station control system. Meanwhile, the invention further discloses a method for judging and isolating the single-phase earth fault based on the wireless communication master station centralized FA, fault judgment and isolation are carried out according to the data and the signals received by the system by applying the preset logic criterion, and the method is used for quickly and accurately judging and isolating the single-phase earth fault. Through deep analysis of sudden changes and characteristic waves of signals such as voltage and current, the speed and reliability of fault determination are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power grid operation and maintenance management, and more specifically to a system and method for determining and isolating single-phase grounding faults based on a centralized FA of a wireless communication master station. Background Art

[0002] In the 10kV power distribution network power supply system, single-phase grounding is the main fault form of power grid operation, accounting for more than 60% of the total faults in the entire power grid, and a considerable number of phase-to-phase short-circuit faults are caused by single-phase grounding faults.

[0003] At present, the methods for judging unidirectional grounding faults are divided into impedance method, S injection method, section search method, traveling wave method and intelligent switch method in principle; they are divided into single-end injection collection and double-end injection collection in terms of fault quantity injection and collection; and they are divided into on-site judgment of grounding intervals through FTU function and judgment of grounding intervals through centralized FA function of automation master station in terms of grounding fault interval positioning.

[0004] (1) Currently, most distribution networks use intelligent switching methods to identify and isolate single-phase grounding faults: A. Identify grounding through the change of zero-sequence voltage collected by the switch; B. Identify grounding through the zero-sequence current collected by the switch; C. Identify grounding through the phase difference between zero-sequence voltage and zero-sequence current collected by the switch; D. Identify grounding through the transient sequence characteristic wave collected by the switch; E. Identify single-phase grounding through the first half wave; F. Identify single-phase grounding through the single-phase grounding fault flip of the fault indicator and the single-phase grounding alarm.

[0005] (2) Advanced cities use the master station centralized wired communication judgment method: the measurement data of (1) is transmitted in real time through Ethernet to judge the single-phase grounding fault interval, and the single-phase grounding fault is isolated by master station tripping and reclosing. Wired communication is mainly used to transmit Uan, Ubn, Ucn, Uo, and I0 in real time when single-phase grounding occurs, and the single-phase grounding interval is determined by the protection setting difference calculation (the delay time difference can be in milliseconds: 0-2 milliseconds).

[0006] (3) For most county and mountainous distribution networks, the master station manually collects data for judgment: the one-way grounding fault interval is judged by the sudden change of the data (1) with communication delay and the alarm information, and the one-way grounding fault is isolated by remote control of the master station. This method is also a relatively effective method for judging single-phase grounding, but it requires manual collection of relevant data (1) for comparison and analysis to judge single-phase grounding, which takes a long time and requires professional personnel to be on duty 24 hours a day.

[0007] Based on the above and a large amount of grounding operation experience, the inventor has determined a method for analyzing and isolating single-phase grounding faults based on a centralized FA of a wireless communication master station. Summary of the invention

[0008] In view of the shortcomings of the prior art, the present invention provides a system and method for determining and isolating single-phase grounding faults based on a wireless communication master station centralized FA, which is used to quickly and accurately determine and isolate single-phase grounding faults. By deeply analyzing the mutation amount and characteristic waves of signals such as voltage and current, the speed and reliability of fault determination are improved.

[0009] To achieve the above-mentioned object, the present invention provides the following technical solution: a system for determining and isolating single-phase grounding faults based on a wireless communication master station centralized FA, characterized in that it includes a substation zero-sequence voltage transformer, a sequence characteristic wave injection device, a primary and secondary fusion vacuum circuit breaker feeder terminal (FTU), a primary and secondary fusion vacuum circuit breaker, a fault indicator, a wireless communication system and a master station control system,

[0010] The substation zero-sequence voltage transformer collects the changes of Uan, Ubn, Ucn and U0, I0 to determine single-phase grounding, and transmits it to the power dispatching master station, and is associated with the distribution network automation master station at the same time;

[0011] The one-way grounding sequence characteristic wave injection device simultaneously collects the changes of Uan, Ubn, Ucn and U0, I0 to judge the single-phase grounding and then starts to inject the sequence characteristic wave, and transmits the number of switch closing and opening actions of the sequence characteristic wave injection device and the number of three-phase current sequence characteristic wave groups to the distribution network automation master station through wireless communication;

[0012] The primary and secondary fusion vacuum circuit breaker feeder terminal (FTU) simultaneously collects the corresponding Uan, Ubn, Ucn, U0, I0, first half-wave signal and the change of the number of sequence characteristic wave groups to determine the single-phase grounding, and transmits the data change to the distribution network automation master station through wireless communication;

[0013] The fault indicator simultaneously collects the corresponding Uan, Ubn, Ucn, U0, I0, and the changes in the number of sequence characteristic wave groups to determine single-phase grounding, and transmits the grounding indication and grounding signal to the distribution network automation master station through wireless communication;

[0014] The master station control system is used to make fault determination according to the received signal and the preset master station centralized FA control logic, and execute alarm or trip operation.

[0015] The present invention further discloses a method for determining and isolating single-phase grounding faults based on a wireless communication master station centralized FA, including using the data and signals received by the above system and applying preset logical criteria to perform fault determination and isolation.

[0016] The present invention is further configured as follows: the logic criterion includes:

[0017] Criteria 1: The real-time data of Uan, Ubn, Ucn, and U0 of the substation zero-sequence voltage transformer exceeds the set value and grounding alarm information;

[0018] Criterion 2: The active transmission data of the sudden change quantity of Uan, Ubn, Ucn, U0, and I0 of the sequence characteristic wave injection device exceeds the set value and the grounding alarm information; and the closing and opening action alarm and closing and opening action times of the sequence characteristic wave injection device, the number of sequence characteristic wave groups, and the sequence characteristic wave tripping / alarm information;

[0019] Criterion 3: The mutation amount of the first half-wave signal of Uan, Ubn, Ucn, U0, I0 and the number of sequence characteristic wave groups of the primary and secondary fusion vacuum circuit breaker feeder terminal (FTU) actively transmits data exceeding the set value and grounding trip / alarm information;

[0020] Criteria 4: Fault indicator flip signal and sequence characteristic wave grounding alarm information.

[0021] The present invention is further configured as follows: based on different information of criterion 1, criterion 2, criterion 3 and criterion 4, the nature of the single-phase grounding fault can be determined to be a continuous single-phase grounding fault, a pulse single-phase grounding fault or an arc single-phase grounding fault.

[0022] The present invention is further configured as follows: the determination of the continuous single-phase grounding fault includes: the voltage values ​​in criteria 1-3 will all change and fluctuate slightly and send out a single-phase grounding alarm signal, and the master station collects the mutation amount of active transmission; the sequence characteristic wave injection device of criterion 2 injects the sequence characteristic wave after a delay; the mutation amount of U0 of criterion 3 and the over-limit alarm, the mutation amount of I0 and the over-limit alarm, the sequence characteristic wave group number and the alarm, and the first half-wave mutation amount and the over-limit alarm; the fault indicator of criterion 4 flips and alarms;

[0023] The isolation of the continuous single-phase grounding fault includes: in the judgment of the continuous single-phase grounding fault, the last unit of the power supply line collects the mutation amount of I0 and issues an over-limit alarm, the number of sequence characteristic wave groups and issues an alarm, the mutation amount of the first half wave and issues an over-limit alarm, and at the same time, the last group of fault indicators collects the flip and alarm as the single-phase grounding fault interval, and the master station control system alarms or trips the fault interval.

[0024] The present invention is further configured as follows: the master station control system has a forest fire prevention area selection function. When the power supply line passes through the forest fire prevention area, the forest fire prevention area selection function is activated. Under this function, after the mutation amount of U0 and I0 and the over-limit alarm, and the first half-wave mutation amount and the over-limit alarm, the master station control system will trip the single-phase grounding fault interval or isolate the single-phase grounding fault.

[0025] The present invention is further configured as follows: the determination of the pulsed single-phase grounding fault includes: the voltage values ​​in criteria 1-3 will all undergo time-synchronized pulse changes and fluctuate greatly, a single-phase grounding alarm signal is issued, and the master station collects the number of pulse mutations and the amount of pulse mutations actively transmitted; the number of pulses and the amount of pulse mutations of U0 in criterion 2 are both over-limit alarms, the number of pulses and the amount of pulse mutations of I0 are both over-limit alarms, and the first half-wave pulse mutation amount is both over-limit alarms;

[0026] The isolation of the pulsed single-phase grounding fault includes: in the judgment of the pulsed single-phase grounding fault, the last unit of the power supply line collects the number of pulses and pulse mutation of I0 and issues an over-limit alarm, and the number of pulses and pulse mutation of the first half-wave and issues an over-limit alarm as a single-phase grounding fault interval, and the main station control system issues an alarm or trips the single-phase grounding fault interval.

[0027] The present invention is further configured as follows: the determination method of the arc single-phase grounding fault is the same as the determination method of the pulse single-phase grounding fault, and when U0 and I0 occur continuously and fluctuate greatly, it is determined to be an arc single-phase grounding fault;

[0028] The isolation method of the arc single-phase grounding fault is the same as the isolation method of the pulse single-phase grounding fault.

[0029] The present invention is further configured such that: the master station uses a collection method to exclude the circuit breaker FTU with abnormal communication during centralized FA logic identification.

[0030] The present invention is further configured as follows: the inclusion set method is: when the main station does not collect Ua, Ub, Uc, U0, I0 and the circuit breaker FTU with characteristic wave signal mutation included in the single-phase grounding fault interval, it is deemed that the main station collects Ua, Ub, Uc, U0, I0 and the characteristic wave signal mutation.

[0031] In summary, the present invention has the following beneficial effects:

[0032] The present invention adopts wireless communication mode. When single-phase grounding occurs, the wireless delayed Uan, Ubn, Ucn, U0, I0 mutation and mutation alarm are transmitted to the main station, and then the main station determines the grounding interval within a certain time (the delay time difference can be in seconds: 1-5 seconds). It effectively avoids the problem that wireless communication cannot transmit Uan, Ubn, Ucn, U0, I0 in real time when single-phase grounding occurs.

[0033] The present invention systematically describes and models the parameter changes of the system line voltage, phase voltage, phase current, zero-sequence voltage, zero-sequence current and the first half-wave when a single-phase grounding fault occurs, and compares, analyzes and isolates the single-phase grounding fault through the master station centralized FA logic for the line parameters and injected characteristic sequence waves and fault indicators during various single-phase groundings. The single-phase grounding electrical information can be effectively collected, and the information is transmitted back to the master station control system through wireless communication technology, and then the information is processed through the master station centralized FA, and the type and interval of the single-phase grounding fault are judged according to the judgment criteria, judgment and isolation conditions, and corresponding isolation operations are performed. The present invention can quickly and effectively judge faults and fault intervals, and has reliable correctness and superiority. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is the primary system diagram of the master station centralized FA for analyzing and isolating single-phase grounding faults.

[0035] Figure 2 yes Figure 1 Diagram of transformer and zero-sequence voltage transformer system in medium substation.

[0036] Figure 3 yes Figure 1 System diagram of the medium characteristic wave injection device.

[0037] Figure 4 This is a system diagram of a primary and secondary integrated intelligent vacuum circuit breaker.

[0038] Figure 5 It is a collection diagram of changes in the single-phase grounding master station model system of the power supply line. DETAILED DESCRIPTION

[0039] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0040] This embodiment discloses a single-phase grounding system based on a wireless communication master station centralized FA analysis and isolation. The system structure is as follows: Figure 1 As shown, it includes a substation zero-sequence voltage transformer, a sequence characteristic wave injection device, a primary and secondary fusion vacuum circuit breaker feeder terminal (FTU), a primary and secondary fusion vacuum circuit breaker, a fault indicator, a wireless communication system and a master station control system;

[0041] When a single-phase grounding fault occurs in a 10 kV power supply line, the substation zero-sequence voltage transformer first collects the changes of Uan, Ubn, Ucn and U0, I0 to determine the single-phase grounding, and transmits it to Zone I of the power dispatching master station through the wired communication method of the power dispatching data network, and is associated with Zone I of the distribution network automation master station;

[0042] Secondly, the unidirectional grounding sequence characteristic wave injection device of the power supply line also collects the changes of Uan, Ubn, Ucn, U0 and I0 at the same time to judge the single-phase grounding, and then starts to inject the sequence characteristic wave, and transmits the number of switch closing and opening actions of the sequence characteristic wave injection device and the number of three-phase current sequence characteristic wave groups to the distribution network automation master station area I through wireless communication; the primary and secondary integrated vacuum circuit breaker feeder terminal (FTU) also collects the corresponding Uan, Ubn, Ucn, U0, I0, the first half-wave signal and the changes of the number of sequence characteristic wave groups to judge the single-phase grounding, and transmits the data changes to the distribution network automation master station area I through wireless communication; the fault indicator also collects the corresponding Uan, Ubn, Ucn, U0, I0, and the changes of the number of sequence characteristic wave groups to judge the single-phase grounding, and transmits the grounding flip indication and grounding signal to the distribution network automation master station area I through wireless communication.

[0043] The second is the method of determining and isolating single-phase based on the centralized FA of the wireless communication master station. First, the guiding principle of allowing single-phase grounding of 10 kV power supply lines to operate for two hours is used. In this guiding principle, since the 10kV system usually adopts a low-current grounding system with an ungrounded neutral point or grounded through an arc suppression coil. In this system, the short-circuit current during a single-phase grounding fault is relatively small, so the continuity of power supply can be guaranteed to a certain extent, avoiding the reduction of power supply reliability caused by an immediate power outage. However, if the fault exists for a long time, it may affect the safe and stable operation of the power system, so it is necessary to find the cause of the fault and deal with it within two hours. The above guidance is combined with the delay of wireless communication (delay ≦ 300ms, if the delay is greater than 300ms, the communication may be interrupted), and the active transmission and passive transmission protocols of the wireless communication 101 telecontrol protocol. This protocol is IEC 101, which is an international standard for power system monitoring, control and communication, and is widely used in remote control, remote protection and related communications. The IEC 101 protocol supports a variety of network configurations such as point-to-point, star, and multi-point, which is common knowledge in the field. The present invention applies this standard; the present invention combines the Uan, Ubn, Ucn, U0, I0, first half-wave and sequence characteristic wave group number and grounding flip signals collected by the substation zero-sequence voltage transformer, sequence characteristic wave injection device, primary and secondary fusion vacuum circuit breaker feeder terminal (FTU), fault indicator and other equipment when one-way grounding occurs, and then actively transmits them to the master station after a sudden change alarm occurs, and passively transmits them to the master station during the master station total recruitment cycle, and then judges and isolates the single-phase grounding fault based on the master station wireless communication centralized FA logic.

[0044] Among them, the criteria for judging and isolating the single-phase grounding FA of the master station centralized type are:

[0045] Criteria 1: The real-time data of the substation zero-sequence voltage transformer, Uan, Ubn, Ucn, and U0 exceed the set value and grounding alarm information.

[0046] Criterion 2: Sequence characteristic wave injection device;

[0047] Criteria A: Uan, Ubn, Ucn, U0, I0 mutation data actively transmit data exceeding the set value and grounding alarm information;

[0048] Criteria B: sequence characteristic wave injection device switch closing and opening action alarm and closing and opening action times, sequence characteristic wave group number and sequence characteristic wave tripping / alarm information.

[0049] Criterion 3: primary and secondary fusion vacuum circuit breaker feeder terminal (FTU);

[0050] Criterion A: The sudden change in the first half-wave signals of Uan, Ubn, Ucn, U0, and I0 and the number of sequence characteristic wave groups actively transmits data exceeding the set value and grounding trip / alarm information.

[0051] Criteria 4: Fault indicator flip signal and sequence characteristic wave grounding alarm information.

[0052] The signal parameters are shown in the following table, Table 1:

[0053]

[0054] Further references Figure 5 And give an example:

[0055] When a continuous single-phase grounding occurs in a 10 kV power supply line, the grounding signals of the power supply line equipment before the grounding point undergo the following changes:

[0056] (1) The Ua, Ub, Uc and U0 of the master station model system of the substation zero-sequence PT, sequence characteristic wave injection device and circuit breaker FTU will all change with small fluctuations, and a single-phase grounding alarm signal will be issued. The master station collects the sudden change amount of active transmission and the total amount of passive transmission after the total cycle. Therefore, the single-phase grounding line can be determined after the first total cycle.

[0057] (2) The sequence characteristic wave injection device injects the sequence characteristic wave after a delay;

[0058] (3) The circuit breaker FTU master station image model system collects:

[0059] The sudden change of U0 will trigger an alarm if it exceeds the limit (limit value: △U0, △t);

[0060] The sudden change of I0 will trigger an alarm if it exceeds the limit (limit value: △I0, △t);

[0061] Sequence characteristic wave group number and alarm (threshold value: 2-8 groups);

[0062] The first half-wave sudden change quantity exceeds the limit and gives an alarm (alarm threshold value: ≥1 times);

[0063] It should be noted that in the early stage of continuous grounding, due to the collision of foreign objects with the ground during the grounding process, pulse grounding or arc grounding may occur.

[0064] (4) The fault indicator master station image model system collects: flip card and alarm

[0065] For the analysis and isolation of continuous single-phase grounding faults, after the centralized FA logic judgment of the master station: the last unit of the power supply line collects the mutation of I0 and issues an over-limit alarm, the number of sequence characteristic wave groups and issues an alarm, the mutation of the first half wave and issues an over-limit alarm, and at the same time, the last group of fault indicators collects the flip and alarm as the single-phase grounding fault section. The centralized FA of the master station issues an alarm or trips the single-phase grounding fault section, and the single-phase grounding or isolation continuous grounding fault is determined.

[0066] At the same time, as a preferred option, when the power supply line passes through the forest fire prevention area, the mutation amount of U0 and I0 exceeds the limit alarm, and the first half-wave mutation amount exceeds the limit alarm. The main station centralized FA will trip the single-phase grounding fault section or isolate the single-phase grounding fault. The main station centralized FA can be set with the selection function of forest fire prevention area and general area to enhance the safety protection of forest fire prevention area.

[0067] Furthermore, when a pulsed single-phase grounding occurs in a 10 kV power supply line, that is, when a grounding signal is on and off, the grounding signal of the power supply line equipment before the grounding point undergoes the following changes:

[0068] (1) The Ua, Ub, Uc and U0 of the master station model system of the substation zero-sequence PT, sequence characteristic wave injection device and circuit breaker FTU will all undergo time-synchronized pulse changes and fluctuate greatly, issuing a single-phase grounding alarm signal. The master station collects the number and amount of pulse mutations actively transmitted.

[0069] (2) The circuit breaker FTU master station image model system collects:

[0070] The pulse number and pulse mutation amount of U0 will exceed the limit and give an alarm (exceeding the limit value: △U0, △t, pulse number ≥ 4 times);

[0071] The number of pulses and pulse mutation of I0 will be out of limit and give an alarm (out of limit value: △I0, △t, number of pulses ≥ 4 times);

[0072] The first half-wave pulse mutation quantity exceeds the limit and an alarm is issued (alarm threshold value: ≥4 times).

[0073] Analysis and isolation of pulsed single-phase grounding faults: After analysis by the centralized FA logic of the master station: the last unit in the power supply line collects the number of pulses and pulse mutation of I0 and issues an over-limit alarm, the number of pulses and pulse mutation of the first half-wave and issues an over-limit alarm, and the centralized FA of the master station alarms or trips the single-phase grounding fault section.

[0074] Furthermore, the method for determining and isolating an arcing single-phase grounding fault is similar to that for a pulsed single-phase grounding fault, except that U0 and I0 of an arcing single-phase grounding fault will occur continuously and fluctuate greatly.

[0075] Furthermore, in the abnormal processing of determining and isolating single-phase grounding in the centralized FA of the wireless communication master station of the present invention, since there are N circuit breakers FTU before the grounding point of the 10 kV power supply line, there may be a phenomenon that the communication of a circuit breaker FTU before the grounding point is interrupted, the communication delay is large (delay > 300ms), and the communication is intermittent. The master station centralized FA logic identification adopts the inclusion set method to exclude the circuit breaker FTU with abnormal communication, thereby more effectively determining and isolating single-phase grounding (tripping or alarm).

[0076] Furthermore, the inclusion set method is: when the master station does not collect Ua, Ub, Uc, U0, I0 and characteristic wave signal mutations in the single-phase grounding fault interval, the circuit breaker FTU is included in the fault interval, it is considered that the master station collects Ua, Ub, Uc, U0, I0 and characteristic wave signal mutations, so as to more effectively determine and isolate single-phase grounding. Through the above settings, signal errors caused by abnormal communication are eliminated, the system's determination and isolation of single-phase grounding (tripping or alarm) are simplified, and the response speed is accelerated.

[0077] Furthermore, the present invention is applicable to the analysis and isolation of single-phase grounding faults in a 10kV line neutral point non-effectively grounded system. Based on the centralized FA judgment and isolation single-phase grounding system and method of the wireless communication master station, the system line voltage, phase voltage, phase current, zero-sequence voltage, zero-sequence current and parameter changes of the first half-wave when a single-phase grounding fault occurs are systematically described and modeled, and the line parameters and injected characteristic sequence waves and fault indicators of various single-phase groundings are compared, analyzed and isolated through the centralized FA logic of the master station. The principles and criteria of single-phase grounding electrical signal collection, analysis and isolation of single-phase grounding of the present invention are reliable and sufficient, and have good accuracy and superiority.

[0078] The advantage of the present invention is that it adopts wireless communication to determine the grounding interval. The existing master station basically uses wired communication. Wired communication mainly allows Uan, Ubn, Ucn, Uo, and I0 to be transmitted in real time when single-phase grounding occurs, and the single-phase grounding interval is determined by calculating the protection setting difference (the delay time difference can be in the millisecond level: 0-2 milliseconds). However, when single-phase grounding occurs, Uan, Ubn, Ucn, Uo, and I0 cannot be transmitted in real time by wireless communication. Therefore, the traditional method can only be judged manually. The present invention can transmit the wireless delayed Uan, Ubn, Ucn, Uo, and I0 mutation amount and mutation alarm to the master station, and then the master station judges within a certain time (the delay time difference can be in the second level: 1-5 seconds), thereby determining the grounding interval. For most county and mountain distribution networks that do not have wired communication conditions, wireless communication is used to quickly determine and isolate single-phase grounding faults.

[0079] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the design concept of the present invention should be included in the protection scope of the present invention.

Claims

1. A system for determining and isolating single-phase grounding faults based on a wireless communication master station centralized FA, characterized by: It includes substation zero-sequence voltage transformer, sequence characteristic wave injection device, primary and secondary fusion vacuum circuit breaker feeder terminal (FTU), primary and secondary fusion vacuum circuit breaker, fault indicator, wireless communication system and master station control system. The substation zero-sequence voltage transformer collects the changes of Uan, Ubn, Ucn and U0, I0 to determine single-phase grounding, and transmits it to the power dispatching master station, and is associated with the distribution network automation master station at the same time; The one-way grounding sequence characteristic wave injection device simultaneously collects the changes of Uan, Ubn, Ucn and U0, I0 to judge the single-phase grounding and then starts to inject the sequence characteristic wave, and transmits the number of switch closing and opening actions of the sequence characteristic wave injection device and the number of three-phase current sequence characteristic wave groups to the distribution network automation master station through wireless communication; The primary and secondary fusion vacuum circuit breaker feeder terminal (FTU) simultaneously collects the corresponding Uan, Ubn, Ucn, U0, I0, first half-wave signal and the change of the number of sequence characteristic wave groups to determine the single-phase grounding, and transmits the data change to the distribution network automation master station through wireless communication; The fault indicator simultaneously collects the corresponding Uan, Ubn, Ucn, U0, I0, and the changes in the number of sequence characteristic wave groups to determine single-phase grounding, and transmits the grounding indication and grounding signal to the distribution network automation master station through wireless communication; The master station control system is used to make fault determination according to the received signal and the preset master station centralized FA control logic, and execute alarm or trip operation.

2. A method for determining and isolating single-phase grounding faults based on a centralized FA of a wireless communication master station, characterized in that: It includes using the data and signals received by the system as claimed in claim 1 and applying preset logical criteria to perform fault determination and isolation.

3. The method for determining and isolating single-phase grounding fault based on centralized FA of wireless communication master station according to claim 2 is characterized in that: The logical criteria include: Criteria 1: The real-time data of Uan, Ubn, Ucn, and U0 of the substation zero-sequence voltage transformer exceeds the set value and grounding alarm information; Criterion 2: The active transmission data of the sudden change quantity of Uan, Ubn, Ucn, U0, and I0 of the sequence characteristic wave injection device exceeds the set value and the grounding alarm information; and the closing and opening action alarm and closing and opening action times of the sequence characteristic wave injection device, the number of sequence characteristic wave groups, and the sequence characteristic wave tripping / alarm information; Criterion 3: The mutation amount of the first half-wave signal of Uan, Ubn, Ucn, U0, I0 and the number of sequence characteristic wave groups of the primary and secondary fusion vacuum circuit breaker feeder terminal (FTU) actively transmits data exceeding the set value and grounding trip / alarm information; Criteria 4: Fault indicator flip signal and sequence characteristic wave grounding alarm information.

4. The method for determining and isolating single-phase grounding fault based on centralized FA of wireless communication master station according to claim 3 is characterized in that: According to different information of Criteria 1, Criteria 2, Criteria 3 and Criteria 4, the nature of the single-phase grounding fault can be determined as a continuous single-phase grounding fault, a pulse single-phase grounding fault or an arc single-phase grounding fault.

5. The method for determining and isolating single-phase grounding fault based on centralized FA of wireless communication master station according to claim 4 is characterized in that: The determination of the continuous single-phase grounding fault includes: the voltage values ​​in criteria 1-3 will all change and fluctuate slightly and send out a single-phase grounding alarm signal, and the master station collects the mutation amount of active transmission; the sequence characteristic wave injection device of criterion 2 injects the sequence characteristic wave after delay; the mutation amount of U0 and the mutation amount of I0 and the mutation amount of sequence characteristic wave groups and the mutation amount of the first half wave and the mutation amount of the first half wave and the mutation amount of the first half wave; the fault indicator of criterion 4 flips and alarms; The isolation of the continuous single-phase grounding fault includes: in the judgment of the continuous single-phase grounding fault, the last unit of the power supply line collects the mutation amount of I0 and issues an over-limit alarm, the number of sequence characteristic wave groups and issues an alarm, the mutation amount of the first half wave and issues an over-limit alarm, and at the same time, the last group of fault indicators collects the flip and alarm as the single-phase grounding fault interval, and the master station control system alarms or trips the fault interval.

6. The method for determining and isolating single-phase grounding fault based on centralized FA of wireless communication master station according to claim 5 is characterized in that: The master station control system has a forest fire prevention area selection function. When the power supply line passes through the forest fire prevention area, the forest fire prevention area selection function is activated. Under this function, after the mutation amount of U0 and I0 and the over-limit alarm, and the first half-wave mutation amount and the over-limit alarm, the master station control system will trip the single-phase grounding fault interval or isolate the single-phase grounding fault.

7. The method for determining and isolating single-phase grounding fault based on centralized FA of wireless communication master station according to claim 4 is characterized in that: The determination of the pulsed single-phase grounding fault includes: the voltage values ​​in criteria 1-3 will all undergo time-synchronized pulse changes and fluctuate greatly, a single-phase grounding alarm signal is issued, and the master station collects the number and amount of pulse mutations of active transmission; the number and amount of pulse mutations of U0 in criterion 2 are both over-limit alarms, the number and amount of pulse mutations of I0 are both over-limit alarms, and the first half-wave pulse mutation amount is both over-limit alarms; The isolation of the pulsed single-phase grounding fault includes: in the judgment of the pulsed single-phase grounding fault, the last unit of the power supply line collects the number of pulses and pulse mutation of I0 and issues an over-limit alarm, and the number of pulses and pulse mutation of the first half-wave and issues an over-limit alarm as a single-phase grounding fault interval, and the main station control system issues an alarm or trips the single-phase grounding fault interval.

8. The method for determining and isolating single-phase grounding fault based on centralized FA of wireless communication master station according to claim 7 is characterized in that: The determination method of the arcing single-phase grounding fault is the same as the determination method of the pulse single-phase grounding fault, and when U0 and I0 occur continuously and fluctuate greatly, it is determined to be an arcing single-phase grounding fault; the isolation method of the arcing single-phase grounding fault is the same as the isolation method of the pulse single-phase grounding fault.

9. The method for determining and isolating single-phase grounding fault based on centralized FA of wireless communication master station according to claim 2, characterized in that: The master station centrally identifies the FA logic by using a collection method to exclude the circuit breaker FTU with abnormal communication.

10. The method for determining and isolating single-phase grounding fault based on centralized FA of wireless communication master station according to claim 9, characterized in that: The inclusion set method is: when the main station does not collect Ua, Ub, Uc, U0, I0 and characteristic wave signal mutations in the single-phase grounding fault interval, the circuit breaker FTU is included in the fault interval, it is deemed that the main station has collected Ua, Ub, Uc, U0, I0 and characteristic wave signal mutations.

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