CN112415456A

CN112415456A - Physical simulation platform for detecting power distribution fault indicator and detection method

Info

Publication number: CN112415456A
Application number: CN202011375595.0A
Authority: CN
Inventors: 张超; 彭珑; 马鑫晟; 赵媛; 庞博; 宋新利; 李凤海; 赵娜; 毛婷; 孙云生; 袁文迁; 刘慧林; 胡应宏; 张静岚; 刘羿辰; 龙凯华; 卢毅; 刘亮; 谢丽芳
Original assignee: State Grid Corp of China SGCC; North China Electric Power Research Institute Co Ltd; State Grid Jibei Electric Power Co Ltd; Electric Power Research Institute of State Grid Jibei Electric Power Co Ltd; Chengde Power Supply Co of State Grid Jibei Electric Power Co Ltd
Current assignee: State Grid Corp of China SGCC; North China Electric Power Research Institute Co Ltd; State Grid Jibei Electric Power Co Ltd; Electric Power Research Institute of State Grid Jibei Electric Power Co Ltd; Chengde Power Supply Co of State Grid Jibei Electric Power Co Ltd
Priority date: 2020-11-30
Filing date: 2020-11-30
Publication date: 2021-02-26

Abstract

The embodiment of the application provides a physical simulation platform for detecting a power distribution fault indicator and a detection method, wherein the platform comprises: 380V system and 10kV system; the 380V system comprises: the simulation circuit comprises a 10kV system access point, a parameter unit for simulating the ground capacitance of the corresponding simulation circuit and a load unit for simulating a user load, which are sequentially connected, and the simulation circuit is also provided with a fault access point for connecting the fault generator; the 10kV system comprises a high-voltage feeder unit for connecting a distribution fault indicator, and the high-voltage feeder unit is connected with a 10kV system access point. This application structure is reliable and the reusability is high, can carry out the performance to the distribution fault indicator of different producers or model and detect, guarantees distribution fault indicator's application reliability, effectively improves distribution fault indicator detection's convenience, efficiency and reliability, reduces the detection cost.

Description

Physical simulation platform for detecting power distribution fault indicator and detection method

Technical Field

The application relates to the technical field of power equipment, in particular to a physical simulation platform for detecting a power distribution fault indicator and a detection method.

Background

Along with the increasing dependence degree of people on electric power in production and life, the safety and stability of the power distribution network are more and more important. In a low-current grounding system, when a grounding fault occurs, due to the fact that fault current is small, a fault line and a fault section are difficult to determine, and fault processing time is long and power failure of a non-fault line is caused by a manual pulling test method. Through the installation distribution fault indicator, can directly fix a position trouble district section, reduce the fault handling time, reduce the power failure scope, therefore distribution fault indicator's reliability is vital. Because the fault characteristic quantity of the low-current grounding system is not obvious, the algorithms of various types of power distribution fault indicators are different, the positioning accuracy is also greatly different, and the power distribution fault indicator needs to be subjected to network access detection in order to ensure the reliable operation of a distribution network.

However, the existing devices for detecting the performance of the power distribution fault indicator have the problems of poor structural reliability or incapability of realizing multiplexing and the like, and because the products produced by various manufacturers are different in quality due to different technical levels, the existing power distribution fault indicator detection devices cannot ensure the application reliability of the power distribution fault indicator.

Disclosure of Invention

The physical simulation platform for detecting the power distribution fault indicator is reliable in structure and high in reusability, can detect the performance of the power distribution fault indicator of different manufacturers or models, can effectively improve the convenience, efficiency and reliability of detection of the power distribution fault indicator on the basis of ensuring the application reliability of the power distribution fault indicator, and reduces the detection cost.

In order to solve the technical problem, the application provides the following technical scheme:

in a first aspect, the present application provides a physical simulation platform for detecting a power distribution fault indicator, comprising: 380V system and 10kV system;

the 380V system comprises: the system comprises a fault generator, a 380V bus and a simulation line connected to the 380V bus, wherein the simulation line comprises a 10kV system access point, a parameter unit for simulating the ground capacitance of the corresponding simulation line and a load unit for simulating a user load which are sequentially connected, and the simulation line is also provided with a fault access point; the fault access point is used for connecting the fault generator;

the 10kV system comprises a high-voltage feeder unit used for being connected with a distribution fault indicator, and the high-voltage feeder unit is connected with the 10kV system access point so as to perform performance detection on the distribution fault indicator based on the 380V system.

Further, the high voltage feeder unit includes: access point, switch, step up transformer, first fuse and the 10kV feeder that connects gradually, this high voltage feeder unit still includes: the current transformer, the second fuse and the voltage transformer are sequentially connected with the 10kV feeder line, the primary side of the voltage transformer is grounded, and the secondary side of the voltage transformer is connected with the second fuse;

the 10kV feeder line is used for connecting the power distribution fault indicator;

the access point is connected with the 10kV system access point.

Further, the fault generator includes: a ground fault unit;

the ground fault unit includes: the grounding fault detection circuit comprises a grounding fault access point, a main switch, an arc grounding fault switch, a metal and resistance grounding fault switch, a first grounding resistance unit and a second grounding resistance unit;

the ground fault access point, the main switch, the arc light ground fault switch and the second ground resistance unit are sequentially connected, the metal and resistance ground fault switch is connected with the arc light ground fault switch in parallel, and the arc light ground fault switch and the metal and resistance ground fault switch are connected to the first ground resistance unit;

the ground fault access point is used for connecting with the fault access point.

Further, the first ground resistance unit includes: the circuit comprises a first grounding resistance branch, a second grounding resistance branch, a third grounding resistance branch and a fourth grounding resistance branch which are connected in parallel, wherein the first grounding resistance branch, the second grounding resistance branch, the third grounding resistance branch and the fourth grounding resistance branch are all grounded;

the first grounding resistance branch comprises a switch, and the second grounding resistance branch to the fourth grounding resistance branch respectively comprise a switch and a resistor which are connected in series;

each of the switches in the first ground resistance unit is connected to an arc ground fault switch and a metal and resistance ground fault switch.

Further, the second ground resistance unit includes: the grounding resistor branch circuit comprises a resistor and a switch which are connected in series;

the other side of the grounding resistor branch is connected to the arc grounding fault switch and the metal and resistor grounding fault switch;

the grounding resistance branch circuit is connected with a switch in parallel, a branch circuit formed by the grounding resistance branch circuit and an adjacent resistor is connected with a switch in parallel, and the grounding resistance branch circuit and another branch circuit formed by two adjacent resistors in sequence are connected with a switch in parallel.

Further, the fault generator includes: a short-circuit fault unit;

the short fault unit includes: the phase-to-phase power supply comprises a phase-to-power selection switch and three short-circuit branches, wherein one side of each short-circuit branch is provided with a short-circuit fault access point, and the other side of each short-circuit branch is sequentially connected with a switch and a resistor; each short-circuit branch is respectively connected in parallel with a corresponding branch consisting of a switch and a resistor which are connected with each other;

the phase electricity selection switch is arranged between one side of each short-circuit branch and the corresponding short-circuit fault access point;

each of the resistors in the short-circuit fault unit is grounded via a switch;

the short-circuit fault access point is used for being connected with the fault access point.

Furthermore, the analog lines each include three analog branches, and each analog branch is connected to the three-phase line of the 380V bus in a one-to-one manner.

Further, the parameter unit includes: each grounding capacitor subunit comprises three grounding capacitor branches, and each grounding capacitor branch is connected to each analog branch in a one-to-one mode;

each grounding capacitor branch is provided with a capacitor and a switch which are connected with each other, and each capacitor in the grounding capacitor subunit is grounded.

Further, the load unit includes: a first load subunit and a second load subunit;

the first load subunit includes: the three first load branches are respectively connected to the simulation branches in a one-to-one mode; each first load branch is provided with a switch and a resistor which are connected with each other;

the first load subunit includes: the three second load branches are respectively connected to the simulation branches in a one-to-one mode;

each second load branch is provided with a switch, and the switches in the second load branches are respectively connected with the corresponding resistors or connected to a starting button.

Further, still include: and the 380V power supply is connected to the 380V bus through an isolation transformer.

Further, still include: two 380V bus voltage transformers each connected to the 380V bus.

Further, still include: a neutral point unit connected to the 380V bus via a grounding transformer;

the neutral point unit comprises a first resistor, a second resistor and an arc suppression coil which are connected in parallel, wherein the first resistor and the second resistor are different in resistance value.

Further, still include: a capacitance parameter unit;

the capacitance parameter unit comprises a first ground capacitance simulation subunit and a second ground capacitance simulation subunit;

the first ground capacitance simulation subunit comprises three first capacitance branches, and each first capacitance branch is connected to the three-phase line of the 380V bus in a one-to-one mode; each first capacitor branch comprises a capacitor, a switch and an isolating switch which are connected in sequence;

the two-to-ground capacitance simulation subunit comprises three second capacitance branches, and each second capacitance branch is connected to the three-phase line of the 380V bus in a one-to-one mode; each second capacitor branch comprises a capacitor and an isolating switch which are connected in sequence;

and the capacitors in the capacitance parameter unit are all grounded.

Further, a faulty access point and a transfer type arc suppression device are connected to the 380V bus;

the transfer arc extinction device comprises three grounded switches connected in parallel, and the switches in the transfer arc extinction device are respectively connected to three phase lines of the 380V bus in a one-to-one mode.

In a second aspect, the present application provides a method for detecting a power distribution fault indicator, where the detection of the power distribution fault indicator is implemented by using a physical simulation platform, and the method for detecting the power distribution fault indicator includes:

connecting a high-voltage feeder unit provided with a power distribution fault indicator to the 10kV system access point, and connecting the fault generator to the fault access point;

controlling the 380V system to simulate a fault working condition and a non-fault working condition, and determining a performance detection result of the power distribution fault indicator according to the running state of the power distribution fault indicator, wherein the performance detection result comprises the following steps: at least one of fault location, low current draw, and false alarm detection results.

According to the technical scheme, the physical simulation platform for detecting the power distribution fault indicator and the detection method thereof provided by the application comprise the following steps: 380V system and 10kV system; the 380V system comprises: the system comprises a fault generator, a 380V bus and a simulation line connected to the 380V bus, wherein the simulation line comprises a 10kV system access point, a parameter unit for simulating the ground capacitance of the corresponding simulation line and a load unit for simulating a user load which are sequentially connected, and the simulation line is also provided with a fault access point; the fault access point is used for connecting the fault generator; the 10kV system comprises a high-voltage feeder unit used for being connected with a distribution fault indicator, the high-voltage feeder unit is connected with a 10kV system access point and is based on the 380V system is used for carrying out performance detection on the distribution fault indicator, a physical simulation platform for detecting the distribution fault indicator is reliable in structure and high in reusability, the performance detection can be carried out on the distribution fault indicators of different manufacturers or models, and therefore the convenience, the efficiency and the reliability of detection of the distribution fault indicator can be effectively improved on the basis of ensuring the application reliability of the distribution fault indicator, and the detection cost is reduced.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic connection structure diagram of a physical simulation platform for detecting a power distribution fault indicator in an embodiment of the present application.

Fig. 2 is a schematic connection structure diagram of a 380V system in a physical simulation platform for detecting a power distribution fault indicator in the embodiment of the present application.

Fig. 3 is a schematic diagram of a connection structure of specific components of a 380V system in a physical simulation platform for detecting a power distribution fault indicator in an embodiment of the present application.

Fig. 4 is a schematic structural diagram of a high-voltage feeder unit in a physical simulation platform for detecting a distribution fault indicator in an embodiment of the present application.

Fig. 5 is a schematic structural diagram of a ground fault unit in a physical simulation platform for detecting a power distribution fault indicator in an embodiment of the present application.

Fig. 6 is a schematic structural diagram of a short-circuit fault unit in a physical simulation platform for detecting a distribution fault indicator in an embodiment of the present application.

Fig. 7 is a schematic flow chart illustrating a power distribution fault indicator detection method according to an embodiment of the present application.

Reference numerals:

1. a 380V system;

11. a fault generator;

12. a 380V bus;

13. simulating a line;

131. a 10kV system access point;

132. a failed access point;

1321. a first failed access point;

1322. a second failed access point;

1323. a third failed access point;

1324. a fourth failed access point;

1325. a fifth failed access point;

133. a parameter unit;

1331. a first parameter unit;

1332. a second parameter unit;

1333. a third parameter unit;

1334. a fourth parameter unit;

134. a load unit;

1341. a first load unit;

1342. a second load unit;

1343. a third load unit;

1344. a fourth load unit;

14. a first line;

15. a second line;

16. a third line;

17. a fourth line;

2. a 10kV system;

22. a high-voltage feeder unit;

221. a second harmonic elimination test interface;

222. a first harmonic elimination test interface;

223. a 10kV feeder line;

4. a power distribution fault indicator;

5. a 380V power supply;

6. a transfer arc extinction device;

7. a bus voltage transformer unit;

8. a neutral point unit;

91. a first ground capacitance analog subunit;

92. the second ground capacitance simulates a subunit.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In one or more embodiments of the present application, a distribution fault indicator may also be referred to as a fault indicator for short, and refers to a device installed on a power line (overhead line, cable, and busbar) to indicate a fault current. Because the single-phase grounding fault current in the low-current grounding system is small, fault location is difficult to realize, and the fault position is determined by line patrol personnel, so that the fault point is determined as soon as possible, and the fault indicator is arranged on the line to realize the quick positioning of the fault point. The fault indicator mainly comprises a fault identification, energy acquisition and communication unit. The fault identification unit identifies the fault through characteristic quantities such as fault current change, transient zero sequence current change and the like, and determines the fault position; the energy acquisition unit acquires electric energy from the line to ensure the fault identification and the power supply of the communication unit; the communication unit can communicate with the main station and give an alarm after a fault occurs.

In order to provide structural reliability and reusability of the power distribution fault indicator detection device, an embodiment of the present application provides a physical simulation platform for power distribution fault indicator detection, which is shown in fig. 1, and the physical simulation platform for power distribution fault indicator detection specifically includes the following contents:

380V system 1 and 10kV system 2; the 380V system 1 specifically includes: the system comprises a fault generator 11, a 380V bus 12 and a simulation line 13 connected to the 380V bus 12, wherein the simulation line 13 specifically comprises a 10kV system access point 131, a parameter unit 133 for simulating the ground capacitance of the corresponding simulation line and a load unit 134 for simulating a user load, which are connected in sequence; a fault access point 132 is also arranged on the analog line 13; the failure access point 132 is used for connecting the failure generator 11; the 10kV system 2 specifically includes a high-voltage feeder unit 22 for connecting the distribution fault indicator 4, and the high-voltage feeder unit 22 is connected to the 10kV system access point 131 to perform performance detection on the distribution fault indicator 4 based on the 380V system 1.

Referring to fig. 2 to 6, the 380V bus 12 in the 380V system 1 specifically refers to a simulated 380V bus, and includes three phase lines: the first line a, the second line B and the third line C correspond to each other, each analog line 13 includes three analog branches, and each analog branch is connected to the first line a, the second line B and the third line C of the 380V bus in a one-to-one manner.

It will be appreciated that the same components shown in figure 2 as being provided on the three lines are indicated by a single symbol, it being understood that the components on the three lines may all be indicated by the single symbol, for example, the isolating switches QS-X1 on the first line 14 means that isolating switches are provided on the respective analog branches of the first line 14, and for ease of identification and convenience of presentation, the isolating switches on the respective analog branches of the first line 14 are collectively indicated as QS-X1.

In a specific example of the present application, referring to fig. 2 to 6, the analog branch circuit 13 may be composed of four, i.e., a first line 14, a second line 15, a third line 16 and a fourth line 17.

Firstly, the first line 14 specifically includes an isolating switch QS-X1 and a circuit breaker QF-X1 which are connected with each other, each analog branch of the first line 14 is provided with a current transformer X1TAa, a current transformer X1TAb and a current transformer X1TAc which are connected with the circuit breaker QF-X1, the current transformer X1TAa, the current transformer X1TAb and the current transformer X1TAc are all connected to the current transformer X1TAo, the current transformer X1TAo is connected with a 10kV system access point 131 of each analog branch of the first line 14, and the 10kV system access point 131 of each analog branch is connected with a corresponding second fault access point 1322, a parameter unit 133 for simulating a corresponding analog line to ground capacitance and a load unit 134 for simulating a user load; the second failure access point 1322 is configured to be connected to the failure generator 11, wherein the parameter unit 133 corresponding to the first line 14 may specifically select the first parameter unit 1331, and the load unit 134 corresponding to the first line 14 may specifically select the first load unit 1341.

The first parameter unit 1331 specifically includes:each grounding capacitor subunit comprises three grounding capacitor branches, and each grounding capacitor branch is connected to each analog branch in a one-to-one mode; one grounding capacitor branch is provided with a capacitor C11 and a switch KM-C11 which are connected with each other, and the capacitance value C is₁₁5.1 μ F; the other grounding capacitor branch is provided with a capacitor C12 and a switch KM-C12 which are connected with each other, and the capacitance value C is₁₂5.1 muf, and each of the capacitors in the grounded capacitor subunit is grounded. In addition, the current value Ic of the first parameter unit 1331₁＝2A。

The first load unit 1341 specifically includes: a first load subunit and a second load subunit; the first load subunit specifically includes: the three first load branches are respectively connected to the simulation branches in a one-to-one mode; each first load branch is provided with a switch KM-X1R1 and a resistor R11 which are connected with each other, and the specification of the resistor R11 is 55 omega, 4A; the first load subunit further includes: the three second load branches are respectively connected to the simulation branches in a one-to-one mode; each second load branch is provided with a switch KM-X1M, the switches KM-X1M in each second load branch are respectively connected to a start button SF1, and the current value I of each second load branch_L11A, and the load current of the first load unit 1341 is 5A.

Secondly, the second line 15 specifically includes an isolating switch QS-X2 and a circuit breaker QF-X2 which are connected with each other, each analog branch of the second line 15 is provided with a current transformer X2TAa, a current transformer X2TAb and a current transformer X2TAc which are connected with the circuit breaker QF-X2, the current transformer X2TAa, the current transformer X2TAb and the current transformer X2TAc are all connected to the current transformer X2TAo, the current transformer X2TAo is connected with a 10kV system access point 131 of each analog branch of the second line 15, and the 10kV system access point 131 of each analog branch is connected with a corresponding third fault access point 1323, a parameter unit 133 for simulating a corresponding analog line ground capacitance and a load unit 134 for simulating a user load; the third failed access point 1323 is configured to connect to the fault generator 11, where the parameter unit 133 corresponding to the second line 15 may specifically select the second parameter unit 1332, and the load unit 134 corresponding to the second line 15 may specifically select the second load unit 1342.

The second parameter unit 1332 specifically includes: each grounding capacitor subunit comprises three grounding capacitor branches, and each grounding capacitor branch is connected to each analog branch in a one-to-one mode; one grounding capacitor branch is provided with a capacitor C21 and a switch KM-C21 which are connected with each other, and the capacitance value C is₂₁15 μ F; the other grounding capacitor branch is provided with a capacitor C22 and a switch KM-C22 which are connected with each other, and the capacitance value C is₂₂15 μ F and each of the grounded capacitance subunits is grounded. In addition, the current value Ic of the second parameter unit 1332₂＝6A。

The second load unit 1342 specifically includes: a first load subunit and a second load subunit; the first load subunit specifically includes: the three first load branches are respectively connected to the simulation branches in a one-to-one mode; each first load branch is provided with a switch KM-X2R1 and a resistor R21 which are connected with each other, and the specification of the resistor R21 is 44 omega, 5A; the first load subunit further includes: the three second load branches are respectively connected to the simulation branches in a one-to-one mode; each of the second load branches is provided with a switch KM-X2R2, the switches KM-X2R2 in each of the second load branches are respectively connected to a corresponding resistor R22, the specification of the resistor R22 is 44 Ω, 5A, and the load current of the second load unit 1342 is 10A.

Thirdly, the third line 16 specifically includes an isolating switch QS-X3 and a circuit breaker QF-X3 which are connected to each other, each analog branch of the third line 16 is provided with a current transformer X3TAa, a current transformer X3TAb and a current transformer X3TAc which are connected to the circuit breaker QF-X3, the current transformer X3TAa, the current transformer X3TAb and the current transformer X3TAc are all connected to the current transformer X3TAo, the current transformer X3TAo is connected to a 10kV system access point 131 of each analog branch of the third line 16, and the 10kV system access point 131 of each analog branch is connected to a parameter unit 133 for simulating the ground capacitance of the corresponding analog line, a fourth fault access point 1324 corresponding to each other and a load unit 134 for simulating a user load; the fourth faulty access point 1324 is configured to connect to the fault generator 11, where the parameter unit 133 corresponding to the third line 16 may specifically select a third parameter unit 1333, and the load unit 134 corresponding to the third line 16 may specifically select a third load unit 1343.

The third parameter unit 1333 specifically includes: each grounding capacitor subunit comprises three grounding capacitor branches, and each grounding capacitor branch is connected to each analog branch in a one-to-one mode; one grounding capacitor branch is provided with a capacitor C31 and a switch KM-C31 which are connected with each other, and the capacitance value C is₃₁5.1 μ F; the other grounding capacitor branch is provided with a capacitor C32 and a switch KM-C32 which are connected with each other, and the capacitance value C is₃₂15 μ F and each of the grounded capacitance subunits is grounded. In addition, the current value Ic of the third parameter unit 1333₃＝4A。

The third load unit 1343 specifically includes: a first load subunit and a second load subunit; the first load subunit specifically includes: the three first load branches are respectively connected to the simulation branches in a one-to-one mode; each first load branch is provided with a switch KM-X3R1 and a resistor R31 which are connected with each other, and the specification of the resistor R31 is 55 omega, 5A; the first load subunit further includes: the three second load branches are respectively connected to the simulation branches in a one-to-one mode; each of the second load branches is provided with a switch KM-X3R2, the switches KM-X3R2 in each of the second load branches are respectively connected to a corresponding resistor R32, the specification of the resistor R32 is 55 Ω, 4A, and the load current of the third load unit 1343 is 8A.

Fourthly, the fourth line 17 specifically includes an isolating switch QS-X4 and a circuit breaker QF-X4 which are connected with each other, each analog branch of the fourth line 17 is provided with a current transformer X4TAa, a current transformer X4TAb and a current transformer X4TAc which are connected with the circuit breaker QF-X4, the current transformer X4TAa, the current transformer X4TAb and the current transformer X4TAc are all connected to the current transformer X4TAo, the current transformer X4TAo is connected with a 10kV system access point 131 of each analog branch of the fourth line 17, and the 10kV system access point 131 of each analog branch is connected with a parameter unit 133 for simulating the ground capacitance of the corresponding analog line, a fifth fault access point 1325 corresponding to each other and a load unit 134 for simulating a user load; the fifth faulty access point 1325 is configured to connect to the fault generator 11, where the parameter unit 133 corresponding to the fourth line 17 may specifically select the fourth parameter unit 1334, and the load unit 134 corresponding to the fourth line 17 may specifically select the fourth load unit 1344.

The fourth parameter unit 1334 specifically includes: the grounding capacitor electronic unit comprises three grounding capacitor branches, and each grounding capacitor branch is respectively connected to each analog branch in a one-to-one mode; the grounding capacitor branch is provided with a capacitor C41 and a switch KM-C41 which are connected with each other, and the capacitance value C is₄15 μ F; and each capacitor in the grounded capacitor subunit is grounded. In addition, the current value Ic of the fourth parameter unit 1334₄＝3A。

The fourth load unit 1344 specifically includes: a first load subunit and a second load subunit; the first load subunit specifically includes: the three first load branches are respectively connected to the simulation branches in a one-to-one mode; each first load branch is provided with a switch KM-X4R1 and a resistor R41 which are connected with each other, and the specification of the resistor R41 is 44 omega, 5A; the first load subunit further includes: the three second load branches are respectively connected to the simulation branches in a one-to-one mode; each second load branch is provided with a switch KM-X4M, the switches KM-X4M in each second load branch are respectively connected to a start button SF2, and the current value I of each second load branch_L21A and the load current of the fourth load unit 1344 is 6A.

In addition, referring to fig. 2 to 6, the physical simulation platform for detecting the power distribution fault indicator further includes: a 380V power supply 5, wherein the 380V power supply 5 can be connected to the 380V bus via an isolation transformer ZT. The circuit where the 380V power supply 5 is located specifically includes: a first power supply line connected to the first line a, a second power supply line connected to the second line B, and a third power supply line connected to the third line C, respectively. The first power supply line, the second power supply line and the third power supply line are respectively provided with isolating switches QS-Z1 which are connected with one another, each isolating switch QS-Z1 is respectively connected with a corresponding switch KM-Z1, each switch KM-Z1 is respectively connected with a current transformer Z1TA, a current transformer Z2TA and a current transformer Z3TA in a one-to-one mode, each switch KM-Z1 and the corresponding current transformer are directly connected to a 380V bus voltage transformer ZTV through a breaker QF-PT, the current transformer Z1TA, the current transformer Z2TA and the current transformer Z3TA are all connected to an isolating transformer ZT, the isolating transformer ZT is respectively connected with corresponding isolating switches QS-Z2 on the first power supply line, the second power supply line and the third power supply line, each isolating switch QS-Z2 is respectively connected with a corresponding switch KM-Z2 in a one-to one mode, and each switch QS-Z2 is respectively connected with the first power supply line, And the current transformer Z2TAa, the current transformer Z2TAb and the current transformer Z2Tac correspond to the second power supply line and the third power supply line respectively, and the current transformer Z2TAa, the current transformer Z2TAb and the current transformer Z2Tac are connected to one current transformer Z2 TAa.

The 380V bus of the physical simulation platform for detecting the power distribution fault indicator is also connected with a first fault access point 1321 and a transfer type arc suppression device 6; the transfer arc suppression device 6 specifically comprises three grounded switches connected in parallel, namely a switch KM-XHC, a switch KM-XHB and a switch KM-XHA, and the switch KM-XHC, the switch KM-XHB and the switch KM-XHA in the transfer arc suppression device are connected to a third line C, a second line B and a first line a of the 380V bus in a one-to-one manner respectively.

The physical simulation platform for detecting the power distribution fault indicator further specifically comprises: two bus voltage transformer units 7, each bus voltage transformer unit 7 includes a 380V bus voltage transformer connected to the 380V bus, which is 380V bus voltage transformer ZTV1 and 380V bus voltage transformer ZTV 2. A 380V bus voltage transformer ZTV1 is connected to the 380V bus via a switch KM-PT2 and a breaker QF-PT2 respectively; A380V bus voltage transformer ZTV2 is connected to the 380V bus via a circuit breaker QF-PT 1.

The physical simulation platform for detecting the power distribution fault indicator further specifically comprises: a neutral point unit 8, wherein the neutral point unit 8 can be connected to the 380V bus via a grounding transformer JDB; the neutral point unit specifically comprises a first resistor, a second resistor and an arc suppression coil which are connected in parallel, wherein the first resistor and the second resistor have different resistance values. The first resistor is a small resistor NR1, the small resistor NR1 is connected to the current transformer NTA through a switch KM-N1, the second resistor is a high resistor NR2, the high resistor NR2 is connected to the current transformer NTA through a switch KM-N2, the arc suppression coil NXH is connected to the current transformer NTA through a switch KM-N3, the current transformer NTA is connected with a grounding transformer JDB, and the grounding transformer JDB is connected to a 380V bus through a switch KM-JDB and a breaker QF-JDB.

The physical simulation platform for detecting the power distribution fault indicator further specifically comprises: and the capacitance parameter unit specifically comprises a first ground capacitance simulation subunit 91 and a second ground capacitance simulation subunit 92.

The first ground-to-ground capacitance simulation subunit 91 specifically includes three first capacitance branches, and each first capacitance branch is connected to the three-phase line of the 380V bus in a one-to-one manner; each first capacitor branch comprises a capacitor, a switch and an isolating switch which are connected in sequence; specifically, the capacitor MCa2 on one first capacitor branch is connected to the isolating switch QF-MC2A through the switch KM-MC2, the capacitor MCb2 on the other first capacitor branch is connected to the isolating switch QF-MC2B through the switch KM-MC2, the capacitor MCc2 on the other first capacitor branch is connected to the isolating switch QF-MC2C through the switch KM-MC2, the isolating switch QF-MC2A, the isolating switch QF-MC2B and the isolating switch QF-MC2C are all connected to the 380V bus, and the resistance value Cm1 of the first ground capacitor analog subunit 91 is 2.55 μ F.

The two-to-ground capacitance simulation subunit 92 specifically includes three second capacitance branches, and each second capacitance branch is connected to the three-phase line of the 380V bus in a one-to-one manner; each second capacitor branch comprises a capacitor and an isolating switch which are connected in sequence; specifically, the capacitor MCa1 on one second capacitor branch is connected to the 380V bus via the isolating switch QF-MC1A, the capacitor MCb1 on the other second capacitor branch is connected to the 380V bus via the isolating switch QF-MC1B, the capacitor MCc1 on the other second capacitor branch is connected to the 380V bus via the isolating switch QF-MC1C, the capacitors in the capacitor parameter unit are all grounded, and the resistance value Cm1 of the two-pair-ground capacitor analog subunit 92 is 5.1 μ F.

In an embodiment of the physical simulation platform for detecting a distribution fault indicator, the high-voltage feeder unit 22 specifically includes: the high-voltage feeder access point, the switch, the step-up transformer, the first fuse and the 10kV feeder 223 are sequentially connected, and the 10kV feeder 223 is used for being connected with the power distribution fault indicator 4; the high-voltage feeder unit further comprises: the current transformer, the second fuse and the voltage transformer are sequentially connected with the 10kV feeder line, and the primary side of the voltage transformer is grounded; a secondary harmonic elimination test interface 221 is arranged between the secondary side of the voltage transformer and the second fuse; the high-voltage feeder access point is connected with the 10kV system access point.

Referring to fig. 4, there are three groups of high voltage feeder access points, one of which is access point a_LAnd access point A_NA 10kV system access point 131 for connecting a first analog branch in the analog line 13, the first analog branch being a line connected to a first line a of the 380V bus 12; the second is an access point B_LAnd access point B_NA 10kV system access point 131 for connecting a second analog branch in the analog line 13, the second analog branch being a line connected with a second line B of the 380V bus 12; the third is access point C_LAnd access point C_N10kV system access point 131 for connecting a third analogue branch in the analogue line 13, which is a line connected to the third line C of the 380V bus 12.

The high-voltage feeder sheetAccess point a in element 22_LAccess point A_NAccess point B_LAccess point B_NAccess point C_LAnd access point C_NThe voltage boosting transformer PT-XGs is connected through a switch KM-XG, the voltage boosting transformer PT-XGs is connected with first fuses FU-XGs corresponding to each group of high-voltage feeder access points respectively, the first fuses FU-XGs are connected with current transformers TA-XGc corresponding to each group of high-voltage feeder access points respectively, the current transformers TA-XGc are connected with second fuses FU-XGc corresponding to each group of high-voltage feeder access points respectively, the second fuses FU-XGc are connected to the secondary side of a voltage transformer PT-XGc, and a secondary harmonic elimination test interface 221 is arranged between the secondary side of the voltage transformer PT-XGc and the second fuses FU-XGc; the second harmonic elimination test interface 221 is used for connecting a second harmonic elimination device. The primary side of the voltage transformer PT-XGc is grounded, the primary side of the voltage transformer PT-XGc is provided with a primary resonance elimination test interface 222, and the primary resonance elimination test interface 222 is used for being connected with a primary resonance elimination device.

In an embodiment of the physical simulation platform for detecting a power distribution fault indicator, the fault generator specifically includes: a ground fault unit;

referring to fig. 5, the ground fault unit specifically includes: the grounding fault detection circuit comprises a grounding fault access point JGZ, a main switch KM-JZ-1, a current transformer JTA, an arc grounding fault switch KM-J1, a metal and resistor grounding fault switch KM-J2, a first grounding resistor unit and a second grounding resistor unit; the ground fault access point JGZ, the main switch KM-JZ-1, the arc ground fault switch KM-J1 and the second ground resistance unit are sequentially connected, the metal and resistance ground fault switch KM-J2 is connected with the arc ground fault switch KM-J1 in parallel, and the arc ground fault switch KM-J1 and the metal and resistance ground fault switch KM-J2 are both connected to the first ground resistance unit; the ground fault access point JGZ is used to connect with the faulty access point 132.

Wherein, the first grounding resistance unit specifically comprises: the circuit comprises a first grounding resistance branch, a second grounding resistance branch, a third grounding resistance branch and a fourth grounding resistance branch which are connected in parallel, wherein the first grounding resistance branch, the second grounding resistance branch, the third grounding resistance branch and the fourth grounding resistance branch are all grounded;

the first grounding resistance branch specifically comprises a switch KM-J3, and a resistance value R is 0 Ω; the second grounding resistance branch specifically comprises a switch KM-J4 and a resistor J1R which are connected in series, wherein the resistance value R is 7.5 omega; the third grounding resistance branch specifically comprises a switch KM-J5 and a resistor J2R which are connected in series, wherein the resistance value R is 15 omega; the fourth grounding resistance branch specifically comprises a switch KM-J6 and a resistor J3R which are connected in series, wherein the resistance value R is 30 Ω. Each of the switches in the first ground resistance unit is connected to an arc ground fault switch and a metal and resistance ground fault switch.

Wherein, the second grounding resistance unit specifically comprises: the three-phase grounding resistor comprises a grounding resistor branch and three grounding resistors sequentially connected to one side of the grounding resistor branch, wherein the three grounding resistors are respectively a resistor J7R with a resistance value R being 60 omega, a resistor J6R with a resistance value R being 60 omega, a resistor J5R with a resistance value R being 60 omega, a resistor J4R with a resistance value R being 60 omega and a switch KM-J10, the switch KM-J10 and the resistor J4R are connected in parallel with a switch KM-J9, the resistor J5R, the resistor J4R and the switch KM-J10 are connected in parallel with a switch KM-J8, and the resistor J6R, the resistor J5R, the resistor J4R and the switch KM-J10 are connected in parallel with a switch KM-J7.

In an embodiment of the physical simulation platform for detecting a power distribution fault indicator, the fault generator specifically includes: a short-circuit fault unit;

referring to fig. 6, the short-circuit fault unit specifically includes: the phase electricity selection switch KM-DZ and the three short-circuit branches are arranged, one side of each short-circuit branch is provided with a short-circuit fault access point DGZ, and the other side of each short-circuit branch is respectively connected with a switch and a resistor which respectively correspond to each other through a current transformer DTaa, a current transformer DTAb and a current transformer DTAc which respectively correspond to each other one by one; each short-circuit branch is respectively connected in parallel with a corresponding branch consisting of a switch and a resistor which are connected with each other; the phase electricity selection switches KM-DZ are arranged between one side of each short-circuit branch and the corresponding short-circuit fault access point; each of the resistors in the short-circuit fault unit is grounded via a switch; the short-circuit failed access point is used to connect with the failed access point 132. Specifically, the current transformer DTaa is sequentially connected with a switch KM-D2-A and a resistor with the resistance value R being 3.8 omega, and a branch where the switch KM-D2-A and the resistor with the resistance value R being 3.8 omega are located is connected with a branch where the switch KM-D1-A and the resistor with the resistance value R being 1.8 omega are located in parallel; the current transformer DTAb is sequentially connected with a switch KM-D2-B and a resistor with the resistance value R being 3.8 omega, and a branch where the switch KM-D2-B and the resistor with the resistance value R being 3.8 omega are located is connected with a branch where the switch KM-D1-B and the resistor with the resistance value R being 1.8 omega are located in parallel; the current transformer DTAc is sequentially connected with the switch KM-D2-C and a resistor with the resistance value R being 3.8 omega, and a branch where the switch KM-D2-C and the resistor with the resistance value R being 3.8 omega are located is connected with a branch where the switch KM-D1-C and the resistor with the resistance value R being 1.8 omega are located in parallel.

In order to provide structural reliability and reusability of a device for detecting a power distribution fault indicator, an embodiment of the present application provides a method for detecting a power distribution fault indicator implemented by using a physical simulation platform for detecting a power distribution fault indicator provided by the present application, and referring to fig. 7, the method for detecting a power distribution fault indicator specifically includes the following contents:

step 100: connecting a high-voltage feeder unit provided with a power distribution fault indicator to the 10kV system access point, and connecting the fault generator to the fault access point;

step 200: controlling the 380V system to simulate a fault working condition and a non-fault working condition, and determining a performance detection result of the power distribution fault indicator according to the running state of the power distribution fault indicator, wherein the performance detection result comprises the following steps: at least one of fault location, low current draw, and false alarm detection results.

As can be seen from the above description, the power distribution fault indicator detection method provided in the embodiment of the present application can perform performance detection on power distribution fault indicators of different manufacturers or models, and further can effectively improve convenience, efficiency, and reliability of power distribution fault indicator detection on the basis of ensuring application reliability of the power distribution fault indicator, and reduce detection cost.

To further illustrate the solution, in a specific application example of the present application, a power distribution physical simulation platform is used to realize the simulation of the ferromagnetic resonance and various fault conditions. The 380V system comprises a main transformer, a bus, an outgoing line unit, a neutral point grounding module, a short-circuit fault simulation unit, a grounding fault simulation unit, a control unit and a protection unit; the 10kV system comprises a step-up transformer, an analog circuit, a PT and a capacitor. Various operation and fault working conditions are simulated by a 380V system, and the performance detection of the power distribution device is realized by a 10kV system.

The system is powered by a 380V power supply and is powered by a 380V simulation bus through an isolation transformer ZT. The bus is led out of a system neutral point through a grounding transformer JDB, and the neutral point grounding mode (ungrounded, high-resistance grounded, low-resistance grounded, arc suppression coil grounded, one of four) of the system is selected through a change-over switch, and the detailed description is shown in the neutral point equipment description in the module description. ZTV1 and ZTV2 are 380V bus voltage transformers for measuring bus voltage. And the KM-MC2 is a capacitance parameter unit and is used for simulating real ground capacitance parameters of the bus.

The platform comprises 4 simulation lines, wherein the simulation lines comprise a 10kV system access point (a colored dot in a CAD drawing), a fault access point, a parameter unit and a load unit. The 10kV system access point can be connected with a high-voltage feeder unit and is used for realizing the performance detection of devices such as a 10kV power distribution fault indicator and a resonance elimination device; the fault access point can be connected with a ground fault generator or a short-circuit fault generator and is used for simulating various faults; the parameter unit simulates a circuit to realize real circuit parameter simulation; the load unit is used for simulating user load.

Selecting a fault mode (grounding or short circuit) by a selection switch; selecting a short-circuit fault mode (50A three-phase; 50A two-phase one of two) through a change-over switch; the fault simulation unit is controlled by the selector switch according to the fault simulation type, and the relay of the control unit is selectively controlled aiming at the fault type (high-resistance grounding, metal grounding, arc grounding, two-phase short circuit and three-phase short circuit), but the two faults are not allowed to occur simultaneously (software locking);

when the system grounding mode is 'neutral point ungrounded, low-resistance grounding, high-resistance grounding and grounding through an arc suppression coil', the closing time of a fault type (high-resistance grounding, metal grounding, arc grounding, two-phase short circuit and three-phase short circuit) control node is 1s (the time is adjustable);

when the system has single-phase earth fault, the controller calculates the time delay of 0.3S (adjustable time) after the fault occurs, and the system can rapidly switch the bus arc-extinguishing device.

Control unit and protection device

The control units are respectively controlled according to different functions of the system, a centralized control unit is arranged in each cabinet body of the power supply transformer cabinet, the neutral point complete cabinet, the first feed-out line cabinet, the second feed-out line cabinet and the fault simulation cabinet, and independent modular control is carried out by adopting Siemens S7-200 PLC; the field communication system is communicated with the background host, and an operator can complete debugging and fault simulation work of the physical simulation platform at an engineer station.

The main transformer inlet and outlet wires and the feed-out wires are provided with independent protection devices, and the main transformer inlet and outlet wires and the feed-out wires have voltage and current protection functions; the voltage and current accurate measurement function is achieved.

Each feeder line outlet switch is provided with an independent measuring device and has the voltage and current protection function; the voltage and current accurate measurement function is achieved.

(II) technical index

A system power supply: three phases, 380V, 100A, 50 Hz;

line full load operating current: 10A;

line short-circuit current: 1000A;

system capacity flow: 30A;

normally operating the secondary voltage of the voltage transformer PT: 100V;

normally operating the secondary current of the current transformer CT: 5A < ═ 5;

the overall measurement accuracy of the system is 0.5 level.

(III) Main Equipment and parameters

3.1. Cabinet size (GGD)

Power supply transformer cabinet: 1000X 800X 2200mm (width X depth X height);

a neutral point complete cabinet: 1200X 800X 2200mm (width X depth X height)

A feed-out line 1 cabinet: 1000X 800X 2200mm (width X depth X height);

a feed-out line 2 cabinet: 1000X 800X 2200mm (Width X depth X height)

High-voltage feeder cabinet: 1500X 800X 2200mm (width X depth X height);

the fault simulation cabinet comprises: 1200 × 800 × 2200mm (width × depth × height);

the fault recording screen: 800X 2200mm (width X depth X height);

the comprehensive test screen: 800X 2200mm (width X depth X height).

3.2. Main transformer

Rated voltage: 380V;

rated current: 60A;

transformation ratio: 380V/380V;

insulation type: pouring epoxy resin;

rated capacity: 40 kVA;

grouping: YN/zn 11;

1min power frequency withstand voltage: 35 kV.

3.3. Arc suppression coil

Rated voltage: 220V;

rated current: 33A;

the adjusting range is as follows: 3-30A;

1min power frequency withstand voltage: 3 kV.

3.4. Neutral point resistance (high resistance)

Resistance value: 220 omega;

short-time rated current: 20A.

3.5. Neutral point resistance (Low resistance)

Resistance value: 3.34 omega;

short-time rated current: 66A, 10S.

Class I loads

The load type is as follows: a resistance;

rated current: 3A, 2A, 1A;

temperature rise: 30K.

Design description:

a single set of design parameters: 1A, 220 Ω, 220W × 3, star connection.

Selecting a type: the parameters 5A, 220. omega., 5500W alone, 3 star connections (group 1). The power of a single resistor is 25 times of the rated power, and the surface temperature rise is mainly considered;

a single group 1A is realized by taking a single parameter 5A, 220 omega, 5500W and 3 star-shaped wirings (1 group) as reference control.

The resistive loads 4 are combined according to 3A, 2A and 1A, and the first group load IR1 ═ 1A, the second group load IR2 ═ 2A, the third group load IR3 ═ 1A and the fourth group load IR4 ═ 3A.

Class II loads

The load type is as follows: electric machine

Rated current: 0.3A, 0.6A

Design description:

designing parameters of an air feeder: three phases, 380V, 0.3A and 100W;

designing parameters of an air feeder: four groups (feeder cabinets and fault simulation cabinets) of three phases, 380V, 0.2A and 40W;

three groups of impact loads (motors) are summed, wherein the first group load I1 is 0.3A, the second group load IR2 is 0.6A, and the third group load IR3 is 0.9A.

3.8. Fault simulation resistor

Type (2): a resistance;

rated current: 100A (5s), 50A (5s), 5A.

3.9. Inductance

Rated current: 50A;

pressure drop: the single line is only 2%, and when the single line is used for a single line, the two lines are connected in series;

rated voltage: 0.38 kV;

rated capacity: 18.5 KW.

3.10. Power capacitor

Type (2): a three-phase capacitor;

rated current: 5A;

rated voltage: 1.9 kV;

working voltage: 0.38 kV;

rated capacitance: 16.5 uF;

rated capacity: 14.5 Kvar.

3.11. Step-up transformer

Rated voltage: 10.5 kV;

voltage transformation ratio: 0.38// 10/;

insulation type: epoxy casting (three-phase combination Y/Y0);

rated capacity: 20 VA.

3.12. Voltage transformer-high voltage measurement

Rated voltage: 10 kV;

voltage transformation ratio: 10/√ 3/0.1/√ 3/0.1/3 (triple-phase combination Y0/Y0/. DELTA., 0.2 level);

insulation type: pouring epoxy resin, namely pouring the three-phase five-column type;

rated capacity: 15 VA.

3.13. Voltage transformer-bus low voltage measurement

Rated voltage: 0.38 kV;

voltage transformation ratio: 0.38/√ 3/0.1/√ 3/0.1/3 (triple-phase combination Y0/Y0/. DELTA, 0.2 level);

insulation type: non-encapsulated structures, three-phase five-column;

rated capacity: 20 VA.

3.14. High-voltage fuse

The model is as follows: XRNP-12/0.5A, with fuse and socket;

quantity: and 6 sets of the transformer are used for boosting transformer and 10kV voltage transformer.

3.15. Circuit breaker

Plastic case breakers 1 (Main loop + outgoing line + short circuit fault simulation)

Brand name: schneider;

the model is as follows: CVS 160B;

order number: LV 516303;

the type: fixed front connection, 3 poles, In 160 and electromagnetic TM-D protection;

size: (W x H x D, mm) ═ 105x 161x 86;

quantity: and (6) pending determination.

3.16. Current transformer

The model is as follows: LMZ 1-0.66;

parameters are as follows: 10VA, 100/5, 0.2S;

insulation type: and (4) epoxy casting.

3.17. Fault recording

Sampling rate:

the host single-channel A/D maximum sampling speed is 100KSBS, and the actual sampling speed is 5kHz (100 points per cycle). Recording 4 cycles before the fault and 8 cycles after the fault.

Fault recording starting conditions:

starting zero-sequence voltage: as long as the zero sequence voltage of the system exceeds a set starting value (a secondary value, default 10V and optional), the host starts wave recording immediately;

starting phase current: as long as the phase current at any point of the system exceeds a set starting value (a secondary value, 2A is defaulted and can be set), the host computer immediately starts wave recording;

setting a starting value: setting a starting value file in a 'CTPT' subfile in an XDL folder of a host NANDFLASH disk, opening the 'CTPT' subfile to have 4 lines of numbers, wherein the 3 rd line of numbers are zero sequence voltage starting values; the number in row 4 is the phase current start value. The starting value can be changed according to actual needs, and the starting value is stored after the starting value is changed.

(IV) Module Unit

4.1. Interface reservation

A plurality of access points are reserved in the system, all the access points are multiplexing interfaces and can be accessed to various modules such as single-phase earth faults, short-circuit faults, power supplies, loads, contacts and the like.

4.2. Load cell

Through the access port, various types of load units can be conveniently accessed.

The load unit is configured with 1 group, consists of a continuous adjustable resistor, an inductor and a capacitor load system, generates the maximum load current of 10A, and can simulate various power working conditions such as three-phase load unbalance, load sudden-load and sudden-load discharge, lead and lag of different power factors and the like.

4.3. Fault simulation unit

Through the access port, the fault simulation unit module can be accessed, including short-circuit faults and single-phase earth faults.

Short-circuit fault unit: two-phase short circuit and three-phase short circuit can be simulated, and the short circuit current is controllable. And configuring a protection device. The two-phase interphase fault or the three-phase interphase fault is selected through the switch, and the fault resistance of the interphase fault can be selected through the switch.

A ground fault unit: single-phase earth fault unit, single-phase earth fault that can simulate includes: metallic grounding, grounding via different resistances, arc grounding via transition resistors, etc. The grounding resistance selection switch can select 0-240 omega grounding resistance for adjustment. The arc grounding faults of metallic grounding, grounding through different resistance values, metallic arc grounding and transition resistance are simulated through different switch combinations.

4.4. Neutral point device

An independent grounding transformer is configured, a system neutral point is led out, the neutral point is not grounded (all switches are opened), the neutral point is grounded through a low resistor, the neutral point is grounded through an arc suppression coil and the like through a change-over switch, a Z-type wiring is adopted for a grounding transformer JDB, and the capacity is 8.8 kVA; the capacity of the arc suppression coil is 8.8kVA, 11 grades, manual adjustment is carried out, the current compensation range is 10-40A, the level difference is not more than 3A, and manual adjustment is carried out; the low resistance is 3.34 omega 66A 10 s; the high resistance is 220 omega 1A 10 s; and reserves the signal source interface.

4.5. High-voltage feeder line unit

The high-voltage feeder unit raises 380V to 10kV through the step-up transformer, the 10kV feeder 223 is a closed ring, and the ring can be used for installing an actual 10kV distribution fault indicator and is used for verifying the performance of the distribution fault indicator; the step-up transformer is a 10kV true PT, a primary harmonic elimination device installation interface is reserved at a neutral point on a primary side, and a secondary harmonic elimination device interface is reserved on a secondary side, so that the step-up transformer can be used for verifying the performance of a harmonic elimination device.

(V) platform functional description

The platform simulates 4 lines of switching and disconnecting link operation by opening and closing QS-X1-4 and QF-X1-4 switches; inductive load is put into the switch KM-X1M and the switch KM-X4M, and resistive load is put into the switches KM-X1R1 to KM-X4R1, so that load change is simulated and load current is adjusted.

The component state:

1) and (3) fault positioning test:

the test steps are as follows:

a. installing a power distribution fault indicator on the platform;

b. starting a platform, and setting fault parameters in a power distribution fault indicator installation section;

c. the input fault unit records whether the power distribution fault indicator acts correctly;

d. removing faults;

e. changing fault parameters, and repeating the steps c-d;

f. completing all types of faults at all fault positions;

g. closing the platform and ending the test;

h. aggregate power distribution fault indicator action correctness.

Detection evaluation standard:

the identification accuracy of short-circuit faults, metallic ground faults and medium-resistance ground faults can reach 100%, the accuracy of arc light ground faults can reach 80%, and the accuracy of high-resistance ground faults can reach 70%; the power distribution fault indicator should be able to correctly send a card-flipping or flashing alarm after identifying a fault, and simultaneously send data to the master station.

2) Small current electricity taking test:

when the power distribution fault indicator is short of power supply, recording and data transmission are incomplete, and therefore reliability is reduced. The simulation circuit current can be changed by adjusting the load of the simulation platform, and when the circuit current is set to be 5A, the fault identification, alarm and data transmission capability of the power distribution fault indicator are verified.

The test steps are as follows:

a. installing a power distribution fault indicator on the platform;

c. adjusting a load, and setting the line current to be 5A;

d. a fault unit is put into, and whether the alarm function of the power distribution fault indicator is normal or not is checked;

e. removing faults;

f. closing the platform and ending the test;

g. and checking whether the wave recording and data transmission functions of the power distribution fault indicator are normal or not.

3) False alarm test (newly added test content)

The power distribution fault indicator cannot be judged as a ground fault by mistake by simulating the working conditions of line switching and load change through the platform, so that the false alarm capability of the power distribution fault indicator is tested.

The test steps are as follows:

a. installing a power distribution fault indicator on the platform;

b. starting the platform;

c. inputting and cutting off each simulation line, and recording whether a power distribution fault indicator gives a false alarm or not;

d. respectively inputting and cutting resistive loads and inductive loads, and recording whether a power distribution fault indicator gives a false alarm or not;

e. closing the platform and ending the test;

detection evaluation standard:

the power distribution fault indicator cannot generate false alarm conditions when the line and the load are switched and changed.

That is to say, this application has developed a distribution fault indicator performance detection device based on distribution physics emulation platform to propose corresponding detection method. Utilize distribution physics simulation platform simulation various ground connection, short-circuit fault and normal switching, change operating mode such as load, detect distribution fault indicator fault identification degree of accuracy, can detect to various principle type distribution fault indicators, simulate undercurrent operating condition simultaneously, detection device gets can the energy supply ability, realizes the comprehensive detection of performance of distribution fault indicator. And the ferromagnetic resonance and the simulation of various fault working conditions are realized by utilizing a power distribution physical simulation platform. The 380V system comprises a main transformer, a bus, an outgoing line unit, a neutral point grounding module, a short-circuit fault simulation unit, a grounding fault simulation unit, a control unit and a protection unit; the 10kV system comprises a step-up transformer, an analog circuit, a PT and a capacitor. Various operation and fault working conditions are simulated by a 380V system, and the performance detection of the power distribution device is realized by a 10kV system.

The 10kV simulation lead is an insulated lead, and the power distribution fault indicator can be directly arranged on the simulation lead. The 380V system simulates two-phase short circuit and three-phase short circuit by means of a short circuit fault unit, and the ground fault unit simulates metallic grounding, grounding through different resistance values, arc grounding through a transition resistor and the like. Whether the power distribution fault indicator can be correctly identified and alarmed is verified by setting various faults (fault parameters are shown in a table 1) in a power distribution fault indicator installation section; verifying whether the power distribution fault indicator malfunctions or not by setting various faults in other sections; installing a line on the power distribution fault indicator to carry out operations such as switching line, switching operation, load transfer and the like, and verifying whether the power distribution fault indicator malfunctions; load is adjusted to enable the current of the analog line to be 5A, faults are set, and the power distribution fault indicator can work reliably when power is taken at low current. Because the platform simulates the real 10kV fault and operation condition environment, the platform is suitable for the performance detection of distribution fault indicators of various principles and types.

TABLE 1

Grounding position	Bus and feeder
		Ground resistance/omega	0 (metallic), 60 (medium resistance), 180 (high resistance)
Grounding mode	Continuous grounding, arc grounding
		Failure mode	Single phase earthing, interphase short circuit

The performance detection development test of the power distribution fault indicator is as follows:

1) and (3) fault positioning test:

faults are set in the installation section and other sections of the power distribution fault indicator respectively according to various fault parameters shown in the table 1 so as to check whether the power distribution fault indicator can correctly position the faults.

The test steps are as follows:

a. installing a power distribution fault indicator on the platform;

d. removing faults;

e. changing fault parameters, and repeating the steps c-d;

f. completing all types of faults at all fault positions;

g. closing the platform and ending the test;

h. aggregate power distribution fault indicator action correctness.

Detection evaluation standard:

2) Small current electricity taking test:

The test steps are as follows:

a. installing a power distribution fault indicator on the platform;

c. adjusting a load, and setting the line current to be 5A;

e. removing faults;

f. closing the platform and ending the test;

Detection evaluation standard:

when the load current is 5A, the functions of wave recording, alarming and data transmission of the power distribution fault indicator are normal.

The application develops a distribution fault indicator performance detection device based on a distribution physical simulation platform aiming at the problem of incomplete performance of a distribution fault indicator, and provides a corresponding detection method, wherein the main technical key points and points to be protected are as follows:

1) the power distribution physical simulation platform realizes real simulation of various grounding and short-circuit faults and normal operation working conditions, and the 10kV simulation line reserves the mounting position of the power distribution fault indicator, so that the functions of detecting the fault positioning accuracy of the power distribution fault indicator and the small current power taking capability are realized. The platform simulates the real 10kV fault and operation condition environment, so that the platform is suitable for performance detection of distribution fault indicators of various principles and types.

2) And providing a power distribution fault indicator performance detection test item, a test step and a detection evaluation standard.

It is noted that, in this document, relational terms are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element. The terms "upper", "lower", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred devices or elements must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are intended to be inclusive and mean, for example, that they may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the description of the present invention, numerous specific details are set forth. It is understood, however, that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description. Similarly, it should be appreciated that in the foregoing description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. However, the disclosed method should not be interpreted as reflecting an intention that: that the invention as claimed requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention is not limited to any single aspect, nor is it limited to any single embodiment, nor is it limited to any combination and/or permutation of these aspects and/or embodiments. Moreover, each aspect and/or embodiment of the present invention may be utilized alone or in combination with one or more other aspects and/or embodiments thereof.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention, and they should be construed as being included in the following claims and description.

Claims

1. A physical simulation platform for power distribution fault indicator detection, comprising: 380V system and 10kV system;

2. The physical simulation platform for distribution fault indicator detection according to claim 1, wherein the high voltage feeder unit comprises: access point, switch, step up transformer, first fuse and the 10kV feeder that connects gradually, this high voltage feeder unit still includes: the current transformer, the second fuse and the voltage transformer are sequentially connected with the 10kV feeder line, the primary side of the voltage transformer is grounded, and the secondary side of the voltage transformer is connected with the second fuse;

the access point is connected with the 10kV system access point.

3. The physical simulation platform for power distribution fault indicator detection according to claim 1, wherein the fault generator comprises: a ground fault unit;

4. The physical simulation platform for power distribution fault indicator detection according to claim 3, wherein the first ground resistance unit comprises: the circuit comprises a first grounding resistance branch, a second grounding resistance branch, a third grounding resistance branch and a fourth grounding resistance branch which are connected in parallel, wherein the first grounding resistance branch, the second grounding resistance branch, the third grounding resistance branch and the fourth grounding resistance branch are all grounded;

5. The physical simulation platform for power distribution fault indicator detection according to claim 3, wherein the second ground resistance unit comprises: the grounding resistor branch circuit comprises a resistor and a switch which are connected in series;

6. The physical simulation platform for distribution fault indicator detection according to claim 1 or 3, wherein the fault generator comprises: a short-circuit fault unit;

each of the resistors in the short-circuit fault unit is grounded via a switch;

7. The physical simulation platform for distribution fault indicator detection according to claim 1, wherein the analog lines each include three analog branches, and each analog branch is connected to the three-phase line of the 380V bus in a one-to-one manner.

8. The physical simulation platform for power distribution fault indicator detection according to claim 7, wherein the parameter unit comprises: each grounding capacitor subunit comprises three grounding capacitor branches, and each grounding capacitor branch is connected to each analog branch in a one-to-one mode;

9. The physical simulation platform for distribution fault indicator detection of claim 7, wherein the load unit comprises: a first load subunit and a second load subunit;

10. The physical simulation platform for power distribution fault indicator detection according to claim 1, further comprising: and the 380V power supply is connected to the 380V bus through an isolation transformer.

11. The physical simulation platform for power distribution fault indicator detection according to claim 1, further comprising: two 380V bus voltage transformers each connected to the 380V bus.

12. The physical simulation platform for power distribution fault indicator detection according to claim 1, further comprising: a neutral point unit connected to the 380V bus via a grounding transformer;

13. The physical simulation platform for power distribution fault indicator detection according to claim 1, further comprising: a capacitance parameter unit;

and the capacitors in the capacitance parameter unit are all grounded.

14. The physical simulation platform for detecting the distribution fault indicator according to claim 1, wherein a fault access point and a transfer type arc suppression device are connected to the 380V bus;

15. A power distribution fault indicator detection method implemented by a physical simulation platform using the power distribution fault indicator detection of any one of claims 1 to 14, the power distribution fault indicator detection method comprising: