Power distribution network protection test system
The modularly designed distribution network protection testing system utilizes current triggering modules and switch node modules to achieve parallel testing of multiple terminal devices, solving the problems of complexity and high cost in existing testing methods, improving testing efficiency and accuracy, and ensuring the safety and reliability of the distribution network.
Patent Information
- Application Number
- CN202510952045.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-10
- Publication Date
- 2025-11-11
AI Technical Summary
Existing power distribution network protection testing operations are complex, require a lot of manpower, and are costly, making it difficult to achieve full coverage testing.
The modularly designed power distribution network protection test system includes a power supply module, a current trigger module, and a switch node module. The current trigger module adjusts the resistance value to output an adjustable current signal to simulate fault types, and the switch node module connects multiple terminal devices for parallel testing.
It simplifies testing operations, reduces manpower and cost requirements, improves testing efficiency and accuracy, and can comprehensively simulate power distribution network faults, ensuring the reliability and safety of terminal equipment protection functions.
Smart Images
Figure CN120928070A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of distribution network automation technology, and in particular to a distribution network protection testing system. Background Technology
[0002] With the increasing demands for power supply reliability, the ability to quickly isolate and self-heal after a distribution network fault is required. Currently, most distribution networks use current differential protection to isolate faults and feeder automation to restore power to non-faulty areas. Therefore, ensuring the correct coordination of protection functions of multiple distribution automation terminals on the line is particularly important, making the protection function testing of the terminals a crucial step before commissioning.
[0003] Currently, terminal protection function testing is conducted using relay protection devices, which has the following problems:
[0004] (1) The test is difficult and requires manual setting of the state sequence, which places high demands on the operators. If the sequence is set incorrectly, the test will fail.
[0005] (2) High manpower requirements: When testing the protection of multiple terminals at the same time, multiple people need to cooperate.
[0006] (3) The testing cost is high. The cost of a single relay protection device is relatively high. To complete the test, multiple relay protection devices need to cooperate with each other. The investment in testing costs is large, and it is difficult to achieve full coverage of the power supply station's testing capabilities. Summary of the Invention
[0007] This application provides a distribution network protection testing system to solve the problems of complex operation and high cost of existing distribution network protection testing.
[0008] In a first aspect, this application provides a power distribution network protection testing system, the system including a power supply module, a current triggering module, and a switch node module corresponding to the number of power distribution automation terminal devices under test;
[0009] The output terminal of the power supply module is connected to the input terminal of the current trigger module and the first terminal of all the switching node modules, respectively, to convert the mains voltage into three-phase AC voltage and to use the three-phase AC voltage to power the current trigger module and all the switching node modules.
[0010] The output terminal of the current trigger module is connected to the second terminal of each switch node module, and is used to output an adjustable current signal by adjusting its own resistance value.
[0011] Each switch node module is connected to a power distribution automation terminal device under test (PDUT), which uses the adjustable current signal to simulate fault types and perform power distribution network protection function tests on the corresponding PUT.
[0012] This application provides a power distribution network protection testing system, which includes a power supply module, a current trigger module, and switch node modules corresponding to the number of distribution automation terminal devices under test. The output terminal of the power supply module is connected to the input terminal of the current trigger module and the first terminal of all switch node modules, respectively, for converting the mains voltage into a three-phase AC voltage and using the three-phase AC voltage to power the current trigger module and all switch node modules. The output terminal of the current trigger module is connected to the second terminal of each switch node module, for outputting an adjustable current signal by adjusting its own resistance value. Each switch node module is connected to one distribution automation terminal device under test, for simulating fault types using the adjustable current signal and performing distribution network protection function tests on the corresponding distribution automation terminal device under test. This application adopts a modular design of power supply modules, current trigger modules, and switch node modules. The structure is clear, facilitating installation, maintenance, and upgrades. Each module functions independently and can be optimized or replaced accordingly, reducing system complexity and maintenance costs. The current trigger module outputs an adjustable current signal by adjusting its own resistance value, enabling it to simulate currents of different intensities and characteristics. This provides a foundation for simulating various fault types, allowing the test system to more comprehensively and accurately simulate various fault conditions that may occur in the distribution network, improving the comprehensiveness and accuracy of the test. Furthermore, the number of switch node modules corresponds to the number of distribution automation terminal devices under test, with each switch node... Each module can be connected to a single power distribution automation terminal device under test (PDD), enabling parallel testing of multiple PPDD devices. This significantly improves testing efficiency and shortens the testing cycle, making it particularly suitable for batch equipment testing scenarios. Simultaneously, each switch node module uses adjustable current signals to simulate fault types, performing power distribution network protection function tests on the corresponding PPDD device. This realistically simulates current changes during power distribution network faults, effectively verifying the reliability and accuracy of the protection functions of the PPDD device. This helps to promptly identify defects in the protection functions of the equipment, improving the safety and reliability of power distribution network operation. Attached Figure Description
[0013] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0014] Figure 1 This is a schematic diagram of the distribution network protection testing system provided in the embodiments of this application;
[0015] Figure 2 This is a schematic diagram of the structural connection of the power distribution network protection test system provided in the embodiments of this application;
[0016] Figure 3 This is a schematic diagram of the series connection structure of the switch node module provided in the embodiment of this application;
[0017] Figure 4 This is a schematic diagram of the tree-like connection structure of the switch node module provided in the embodiments of this application;
[0018] Figure 5 This is a schematic diagram of the fault structure provided in the embodiments of this application;
[0019] Figure 6 This is a schematic diagram of the test system structure built based on the fault structure provided in the embodiments of this application. Detailed Implementation
[0020] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.
[0021] To make the objectives, technical solutions, and advantages of this application clearer, the following description will be provided in conjunction with the accompanying drawings and specific embodiments.
[0022] To address the problems of complex operation, high personnel requirements, and high costs associated with existing distribution network protection testing devices and methods, this application proposes a low-cost, simplified distribution network protection testing system. This system allows a single person to independently complete differential protection tests on multiple distribution automation terminal devices and verify feeder automation functions, greatly improving the efficiency of on-site testing and providing a fundamental guarantee for reliable operation of distribution network protection and improved power supply reliability.
[0023] Figure 1 This is a schematic diagram of the distribution network protection testing system provided in an embodiment of this application. Figure 1 As shown, the power distribution network protection test system includes a power supply module 1, a current triggering module 2, and a switch node module 3 corresponding to the number of power distribution automation terminal devices under test.
[0024] The output terminal of power module 1 is connected to the input terminal of current trigger module 2 and the first terminal of all switching node modules 3, respectively, to convert the mains voltage into three-phase AC voltage and to use the three-phase AC voltage to power current trigger module 2 and all switching node modules 3.
[0025] The output terminal of the current trigger module 2 is connected to the second terminal of each switch node module 3, and is used to output an adjustable current signal by adjusting its own resistance value.
[0026] Each switch node module 3 is connected to a power distribution automation terminal device under test, which is used to simulate fault types using adjustable current signals and perform power distribution network protection function tests on the corresponding power distribution automation terminal device under test.
[0027] In this embodiment, a switch node module corresponding to the number of power distribution automation terminal devices under test is set up. Through the joint action of the power supply module and the current trigger module, multiple terminal devices can be tested simultaneously, which can not only improve testing efficiency, but also save testing costs and personnel costs.
[0028] This application embodiment is applicable to simultaneous testing of multiple nodes and terminals, eliminating the need for multiple personnel to coordinate and operate multiple devices; one person can complete multi-node system-level testing. Furthermore, the system operation is extremely simple; it only requires connecting the components according to the network structure and applying a current trigger module at the fault location to achieve testing, without the need for complex operations such as voltage setting, current setting, or sequence reversal setting of the relay protection device. Moreover, compared to conventional relay protection testers, this system is not only lower in cost but also lighter and easier to transport.
[0029] In one possible implementation, the power module's output terminals include a three-phase output terminal and a neutral output terminal, and the first terminal of the switching node module includes a first three-phase terminal; the three-phase output terminals of the power module are connected to the first three-phase terminals of all switching node modules, and the neutral output terminal and B-phase output terminal of the power module are respectively connected to the input terminals of the current triggering module; the power module includes a transformer, the primary input terminal of the transformer is connected to the input terminal of the power module, the three-phase terminals of the secondary side of the transformer are respectively connected to the three-phase output terminals, and the neutral terminal of the secondary side of the transformer is connected to the neutral output terminal;
[0030] A transformer is used to convert mains voltage into three-phase AC voltage and output the three-phase AC voltage through the three-phase output terminals.
[0031] Figure 2This is a schematic diagram of a switching node module. The output terminals of power module 1 include three-phase output terminals (A, B, C) and a neutral output terminal (N). The first terminal of switching node module 3 includes a first three-phase terminal (A1, B1, C1). The three-phase output terminals of power module 1 are connected to the first three-phase terminals of switching node module 3 (i.e., A connects to A1, B connects to B1, and C connects to C1). The neutral output terminal N and the B-phase output terminals of power module 1 are respectively connected to the input terminals of the current trigger module (including the first input terminal B4 and the second input terminal N1). Power module 1 includes a transformer T. The primary input terminal of transformer T is connected to the input terminal, the three-phase terminals of the secondary side of transformer T are respectively connected to the three-phase output terminals, and the neutral terminal of the secondary side of transformer T is connected to the neutral output terminal.
[0032] For example, refer to Figure 2 The primary input terminal of power module 1 (i.e., the primary input terminal of transformer T) is a 220V AC mains input. The primary input terminal includes three input nodes: L (live wire), N (neutral wire), and G (ground wire). After being transformed by transformer T, the secondary side obtains a 100V AC voltage. The secondary side has four nodes: three-phase output terminals (A, B, C) and neutral output terminal N. The A-phase output terminal, the neutral output terminal N, and the C-phase output terminal are all connected to a secondary side node, corresponding to the primary side node L. The B-phase output terminal is connected to a secondary side node, corresponding to the primary side node N.
[0033] In this embodiment, the power module uses only one transformer to transform the voltage. By changing the wiring of the switch node module and the input / output wiring of the current trigger module, a phase-to-phase voltage difference is formed to meet the voltage acquisition requirements. At the same time, by changing the wiring inside the current trigger module, an adjustable current signal can be generated to meet the protection testing requirements.
[0034] In one possible implementation, the second end of the switching node module includes a second three-phase terminal; the input end of the current trigger module includes a first input terminal and a second input terminal, and the output end of the current trigger module includes a first three-phase output terminal; the first input terminal is connected to the B-phase output terminal of the power supply module, the second input terminal is connected to the neutral line output terminal of the power supply module, and the first three-phase output terminal of the current trigger module is connected to the second three-phase terminal of the switching node module.
[0035] The current-triggered module includes a first resistor, a second resistor, and a third resistor;
[0036] The first end of the first resistor is connected to the A-phase output terminal of the first three-phase output terminal, and the second end of the first resistor is connected to the first input terminal and the second end of the third resistor respectively.
[0037] The first end of the second resistor is connected to the B phase output terminal of the first three-phase output terminal, and the second end of the second resistor is connected to the second input terminal.
[0038] The first end of the third resistor is connected to the C-phase output terminal of the first three-phase output terminal.
[0039] Reference Figure 2 The second terminal of the switch node module 3 includes a second three-phase terminal (A2, B2, C2). The input terminal of the current trigger module 2 includes a first input terminal B4 and a second input terminal N1. The output terminal of the current trigger module 2 includes a first three-phase output terminal (A3, B3, C3). The first input terminal B4 of the current trigger module 2 is connected to the B-phase output terminal of the power supply module 1, and the second input terminal N1 of the current trigger module 2 is connected to the neutral output terminal N of the power supply module 1. The first three-phase output terminals of the current trigger module 2 are connected to the second three-phase terminals of the switch node module, i.e., A2 and A3 are connected, B2 and B3 are connected, and C2 and C3 are connected.
[0040] Additionally, refer to Figure 2 The current trigger module 2 also includes a first resistor R1, a second resistor R2, and a third resistor R3. The first end of the first resistor R1 is connected to the A-phase output terminal A3 of the first three-phase output terminals, and the second end is connected to both the first input terminal B4 and the second end of the third resistor R3. The first end of the second resistor R2 is connected to the B-phase output terminal B3 of the first three-phase output terminals, and the second end is connected to the second input terminal N1. The first end of the third resistor R3 is connected to the C-phase output terminal C3 of the first three-phase output terminals.
[0041] For example, refer to Figure 2 The first three-phase output terminals of the current trigger module 2 are A3, B3, and C3, the first input terminal is B4, and the second input terminal is N1. Node A3 is connected to node B4, and a first resistor R1 is connected in series between them. The resistance value of the first resistor R1 can be adjusted manually or remotely. Node C3 is connected to node B4, and a third resistor R3 is connected in series between them. The resistance value of the third resistor R3 can be adjusted manually or remotely. Node B3 is connected to node N1, and a second resistor R2 is connected in series between them. The resistance value of the second resistor R2 can be adjusted manually or remotely.
[0042] As can be seen from the above examples, the first resistor R1, the second resistor R2, and the third resistor R3 in this embodiment are all adjustable resistors, and their resistance values and adjustment magnitudes are set according to the actual situation.
[0043] The current triggering module in this embodiment outputs an adjustable current signal by adjusting its own resistance value, which can simulate currents of different intensities and characteristics, providing a basis for simulating various fault types. This enables the test system to more comprehensively and accurately simulate various fault conditions that may occur in the power distribution network, improving the comprehensiveness and accuracy of the test.
[0044] In one possible implementation, each switch node module includes a relay switch, a current transformer, a voltage acquisition unit, and a switching device.
[0045] A relay switch is installed between the first and second ends of each switch node module to control the continuity of the line between the first and second ends of each switch node module.
[0046] The first terminal of the current transformer is connected to the second terminal of the relay switch and the corresponding switch node module, and the second terminal of the current transformer is connected to the corresponding power distribution automation terminal under test.
[0047] The first end of the voltage acquisition unit is connected to the first and second ends of the corresponding switch node module, and the second end of the voltage acquisition unit is connected to the corresponding power distribution automation terminal equipment under test.
[0048] The circuit breaker and switchgear are connected to each relay switch and each power distribution automation terminal device under test, respectively. They are used to obtain the circuit breaker and switchgear commands fed back by each power distribution automation terminal device under test when a fault occurs, and control the corresponding relay switch to open according to the circuit breaker and switchgear commands.
[0049] Reference Figure 2 Each switch node module 3 may include a relay switch 31, a current transformer 32, a voltage acquisition unit 33, and a switching device 34.
[0050] A relay switch 31 is installed between the first and second ends of each switch node module 3 to control the continuity of the line between the first and second ends of each switch node module 3.
[0051] Among them, reference Figure 2 Each switch node module 3 has a first three-phase terminal (i.e., A1, B1, C1) at its first end and a second three-phase terminal (i.e., A2, B2, C2) at its second end. The relay switch 31 includes a first relay switch MA, a second relay switch MB, and a third relay switch MC, which are linked together.
[0052] The first terminal of the first relay switch MA is connected to the A-phase terminal A1 of the first three-phase terminal, and the second terminal of the first relay switch MA is connected to the first terminal of the current transformer 32 and the A-phase terminal A2 of the second three-phase terminal.
[0053] The first terminal of the second relay switch MB is connected to the B-phase terminal B1 of the first three-phase terminal, and the second terminal of the second relay switch MB is connected to the first terminal of the current transformer 32 and the B-phase terminal B2 of the second three-phase terminal.
[0054] The first terminal of the third relay switch MC is connected to the C-phase terminal C1 of the first three-phase terminal, and the second terminal of the third relay switch MC is connected to the first terminal and the C-phase terminal C2 of the second three-phase terminal of the current transformer 32.
[0055] Among them, the first relay switch MA, the second relay switch MB, and the third relay switch MC are controlled as a whole, opening and closing simultaneously.
[0056] For example, refer to Figure 2 The first three-phase terminal A1 is connected to the second three-phase terminal A2, and the first relay switch MA is connected in series in between. The first three-phase terminal B1 is connected to the second three-phase terminal B2, and the second relay switch MB is connected in series in between. The first three-phase terminal C1 is connected to the second three-phase terminal C2, and the third relay switch MC is connected in series in between.
[0057] The first end of the current transformer 32 is connected to the line between the relay switch 31 and the second end of the corresponding switch node module 3, and the second end of the current transformer 32 is connected to the corresponding power distribution automation terminal under test.
[0058] Among them, reference Figure 2 The current transformer 32 includes a first current transformer TA1, a second current transformer TA2, and a third current transformer TA3.
[0059] The first terminal of the first current transformer TA1 is connected to the second terminal of the first relay switch MA and the A-phase terminal A2 of the second and third phase terminals, respectively. The second terminal of the first current transformer TA1 is connected to the A-phase current terminal IA of the corresponding power distribution automation terminal equipment under test.
[0060] The first terminal of the second current transformer TA2 is connected to the second terminal of the second relay switch MB and the B-phase terminal B2 of the second and third phase terminals, respectively. The second terminal of the second current transformer TA2 is connected to the B-phase current terminal IB of the corresponding power distribution automation terminal equipment under test.
[0061] The first terminal of the third current transformer TA3 is connected to the second terminal of the third relay switch MC and the C-phase terminal C2 of the second and third phase terminals respectively. The second terminal of the third current transformer TA3 is connected to the C-phase current terminal IC of the corresponding power distribution automation terminal equipment under test.
[0062] In this embodiment, a first current transformer TA1 is installed on the line between MA and A2, a second current transformer TA2 is installed on the line between MB and B2, and a third current transformer TA3 is installed on the line between MC and C2. The secondary current lines of the first current transformer TA1, the second current transformer TA2, and the third current transformer TA3 are respectively led to IA, IB, and IC, and respectively connected to the A-phase current terminal, B-phase current terminal, and C-phase current terminal of the corresponding power distribution automation terminal equipment under test via IA, IB, and IC.
[0063] The voltage acquisition unit 33 is connected to the first and second terminals of the corresponding switch node module 3 via a line connection, and the second terminal of the voltage acquisition unit 33 is connected to the corresponding power distribution automation terminal equipment under test.
[0064] Reference Figure 2 In this embodiment, the voltage acquisition unit 33 is directly composed of three connecting lines: UA on the line between A1 and MA is connected to the A-phase voltage of the corresponding power distribution automation terminal device under test; UB on the line between B1 and MB is connected to the B-phase voltage of the corresponding power distribution automation terminal device under test; and UC on the line between MC and C2 is connected to the C-phase voltage of the corresponding power distribution automation terminal device under test.
[0065] The circuit breaker 34 is connected to each relay switch 31 and each power distribution automation terminal device under test, respectively, to obtain the circuit breaker command fed back by each power distribution automation terminal device under test when a fault occurs, and to control the corresponding relay switch 31 to open according to the circuit breaker command.
[0066] Among them, reference Figure 2 The circuit breaker 34 includes a first node KF, a second node KH, a third node F, a fourth node H, a fourth resistor R4, and a fifth resistor R5.
[0067] The first end of the first node KF, the first end of the second node KH, the first end of the third node F, and the first end of the fourth node H are connected in parallel and then connected to the relay switch 31.
[0068] The first and second ends of the first node KF are connected through the fourth resistor R4, and the first and second ends of the second node KH are connected through the fifth resistor R5.
[0069] The second end of the first node KF is connected to the control opening node of each power distribution automation terminal device under test; the second end of the second node KH is connected to the control closing node of each power distribution automation terminal device under test; the second end of the third node F is connected to the opening position node of each power distribution automation terminal device under test; and the second end of the fourth node H is connected to the closing position node of each power distribution automation terminal device under test.
[0070] Among them, the control wiring of relay switch 31 is connected to the first node KF, the second node KH, the third node F, and the fourth node H respectively. The first node KF, the second node KH, the third node F, and the fourth node H are connected to the control opening node, the control closing node, the opening position, and the closing position of the power distribution automation terminal equipment under test.
[0071] For example, refer to Figure 2 When the first node KF receives a control signal (i.e., a tripping command) from the power distribution automation terminal equipment under test, it can control the first relay switch MA, the second relay switch MB, and the third relay switch MC to open simultaneously. When the second node KH receives a control signal (i.e., a closing command) from the power distribution automation terminal equipment under test, it can control the first relay switch MA, the second relay switch MB, and the third relay switch MC to close simultaneously. When the first relay switch MA, the second relay switch MB, and the third relay switch MC are open simultaneously, the third node F will transmit the switch open signal to the power distribution automation terminal equipment under test. When the first relay switch MA, the second relay switch MB, and the third relay switch MC are closed, the fourth node H will transmit the switch closed signal to the power distribution automation terminal equipment under test.
[0072] In addition, a fourth resistor R4 and a fifth resistor R5 are connected in series on the path between the relay switch 31 and the first node KF and the second node KH, respectively. The two resistors can effectively prevent the switch from malfunctioning due to the voltage signal of the control monitoring circuit.
[0073] In one possible implementation, refer to Figure 2 Each switch node module 3 also includes a fifth node KC and a sixth node C. The first end of the fifth node KC and the first end of the sixth node C are short-circuited. The second end of the fifth node KC and the second end of the sixth node C are connected to the control energy storage end and energy storage location end of the power distribution automation terminal equipment under test.
[0074] In one possible implementation, refer to Figure 2 When there is only one power distribution automation terminal under test, the system includes a switch node module 3. The A1, B1, and C1 of the first three-phase terminal of the switch node module 3 can be connected to the A2, B2, and C2 of the second three-phase terminal of the power distribution automation terminal under test.
[0075] In one possible implementation, when there are at least two power distribution automation terminal devices under test, the system includes at least two switch node modules;
[0076] At least two switch node modules are connected in series in sequence; and the first end of the first switch node module is connected to the output end of the power supply module, and the second end of each switch node module is connected to the output end of the current trigger module.
[0077] For example, refer to Figure 3 There are three distribution automation terminal devices under test connected to the power grid (i.e., device 1, device 2, and device 3). Correspondingly, the system includes three switch node modules 3, and the three switch node modules 3 are connected in series in the order of device 1, device 2, and device 3. The first three-phase terminal of the switch node module 3 corresponding to device 1 is connected to the three-phase output terminal of the power supply module 1. The second three-phase terminal of the switch node module 3 corresponding to device 1 is connected to the first three-phase terminal of device 2 and the first three-phase output terminal of the current trigger module 2, respectively. The second three-phase terminal of device 2 is connected to the first three-phase terminal of device 3 and the first three-phase output terminal of the current trigger module 2, respectively. The second three-phase terminal of device 3 is connected to the first three-phase output terminal of the current trigger module 2.
[0078] In one possible implementation, when there are at least three power distribution automation terminal devices under test, the system includes at least three switch node modules;
[0079] At least three switch node modules are connected in a tree structure; and the first end of the first-level switch node module is connected to the output end of the power supply module, and the second end of each switch node module is connected to the output end of the current trigger module.
[0080] For example, refer to Figure 4 The system includes five distribution automation terminal devices connected to the power grid (device 1, device 2, device 3, device 4, and device 5). Correspondingly, the system comprises five switch node modules 3, connected in a tree structure as device 1, device 2, device 3, device 4, and device 5. The first three-phase terminal of switch node 3 corresponding to device 1 is connected to the three-phase output terminal of power module 1. The second three-phase terminal of device 1 is connected to the first three-phase terminals of switch node module 3 corresponding to device 2, the first three-phase terminals of switch node module 3 corresponding to device 3, and the first three-phase output terminal of current trigger module 2, respectively. The second three-phase terminal of switch node module 3 corresponding to device 2 is connected to the first three-phase terminals of switch node module 3 corresponding to device 4, the first three-phase terminals of switch node module 3 corresponding to device 5, and the first three-phase output terminal of current trigger module 2, respectively. The second three-phase terminal of switch node module 3 corresponding to device 4 is connected to the first three-phase output terminal of current trigger module 2. The second three-phase terminal of switch node module 3 corresponding to device 5 is connected to the first three-phase output terminal of current trigger module 2.
[0081] Since some terminals have control loop open circuit detection function, if used in normal primary and secondary integrated equipment, it will not cause equipment malfunction. However, if used in relay-type analog circuit breakers, it often leads to equipment malfunction. In this embodiment, two resistors (i.e., the fourth resistor R4 and the fifth resistor R5) are connected in series on the path between the control node of the switch node module and the first node KF and the second node KH. The two resistors can effectively prevent the voltage signal of the control monitoring loop from causing switch malfunction.
[0082] Based on the power distribution network protection testing system provided in this application, the following example is demonstrated:
[0083] Reference Figure 5 It involves a total of 5 switches, and the test system is set up as follows: Figure 6 As shown, according to Figure 5 The network architecture shown requires one power supply module, one current trigger module, and five switch node modules. The test system connection diagram is as follows. Figure 6 As shown.
[0084] in, Figure 6 The network architecture shown is as follows:
[0085] The A-phase output terminal, B-phase output terminal, and C-phase output terminal of the power supply module are connected to the A-phase terminal A1, B-phase terminal B1, and C-phase terminal C1 of the first three-phase terminal of the switch node module 1.
[0086] The A-phase terminal A2, B-phase terminal B2, and C-phase terminal C2 of the second three-phase terminal of switch node module 1 are respectively connected to the A-phase terminal A1, B-phase terminal B1, and C-phase terminal C1 of the first three-phase terminal of switch node module 2, the A-phase terminal A1, B-phase terminal B1, and C-phase terminal C1 of the first three-phase terminal of switch node module 3, and the A-phase terminal A1, B-phase terminal B1, and C-phase terminal C1 of the first three-phase terminal of switch node module 5.
[0087] The A-phase terminal A2, B-phase terminal B2, and C-phase terminal C2 of the second three-phase terminal of the switch node module 3 are connected to the A-phase terminal A1, B-phase terminal B1, and C-phase terminal C1 of the first three-phase terminal of the switch node module 4.
[0088] The first input terminal B4 and the second input terminal N1 of the current trigger module are connected to the B-phase output terminal and the neutral output terminal N of the power supply module, respectively.
[0089] After the connection is established, a fault simulation is performed:
[0090] When there is no fault, the A-phase output terminal A3, the B-phase output terminal B3, and the C-phase output terminal C3 of the first three-phase output terminals of the power trigger module are left floating.
[0091] When a fault occurs at F1, the A-phase output terminal A3, B-phase output terminal B3, and C-phase output terminal C3 of the first three-phase output terminal of the current trigger module are connected to the A-phase terminal A2, B-phase terminal B2, and C-phase terminal C2 of the second three-phase terminal of the switch node module 1.
[0092] At this time, the A-phase output terminal of the power supply module is connected to the A-phase terminal A1 of the first three-phase terminal of the switch node module 1. The A-phase terminal A1 of the first three-phase terminal of the switch node module 1 is connected to the A-phase terminal A2 of the second three-phase terminal of the switch node module 1 via the first relay switch MA of the switch node module 1. The A-phase terminal A2 of the second three-phase terminal of the switch node module 1 is connected to the A3 of the current trigger module. Through the transition resistors (R1, R2, R3), it is connected to the B-phase output terminal and the neutral line output terminal N of the power supply module to form a loop and generate current. This current is set to the magnitude of the fault current. At this time, the current IA of the switch node module 1 is the fault current.
[0093] Similarly, the currents in IB and IC of switch node module 1 are also fault currents. After the distribution automation terminal equipment collects the fault current through the IA, IB, and IC nodes, it analyzes the fault through its internal algorithm and determines that a fault has occurred. The distribution automation terminal equipment outputs a tripping command to the first node KF node, controlling the first relay switch MA, the second relay switch MB, and the third relay switch MC of switch node module 1 to trip synchronously. After the first relay switch MA, the second relay switch MB, and the third relay switch MC of switch node module 1 trip, the currents in IA, IB, and IC of switch node module 1 are 0, and the voltage in UC is 0, thus achieving fault isolation. This is consistent with the actual operation on site and completes the test of the protection function of the distribution automation terminal when a fault occurs at fault point F1.
[0094] Meanwhile, since the power distribution automation terminal equipment under test has the function of monitoring the open circuit of remote control opening and closing circuits, during the test, after the switch node module 1 is connected to the power distribution automation terminal equipment under test, the monitoring function of the open circuit of remote control opening and closing circuits inside the power distribution automation terminal equipment under test will apply monitoring electrical signals to the first node KF and the second node KH. Since this system has installed two current-limiting resistors (i.e., the fourth resistor R4 and the fifth resistor R5) in front of the first node KF and the second node KH, the power of the monitoring electrical signal is small, which can avoid the first relay switch MA, the second relay switch MB, and the third relay switch MC from being malfunctioning after the monitoring electrical signal is applied to the first node KF and the second node KH. When the power distribution automation terminal equipment under test sends a control trip or control opening signal, the control signal has a large power and can control the first relay switch MA, the second relay switch MB, and the third relay switch MC to open or close after being applied to the first node KF and the second node KH. This design effectively avoids the malfunction of the switches.
[0095] When the fault occurs at F2, the A-phase output terminal A3, B-phase output terminal B3, and C-phase output terminal C3 of the first three-phase output terminal of the current trigger module are connected to the A-phase terminal A2, B-phase terminal B2, and C-phase terminal C2 of the second three-phase terminal of the switch node module 2. The test operation principle is the same as that of F1.
[0096] When the fault occurs at F3, the A-phase output terminal A3, B-phase output terminal B3, and C-phase output terminal C3 of the first three-phase output terminal of the current trigger module are connected to the A-phase terminal A2, B-phase terminal B2, and C-phase terminal C2 of the second three-phase terminal of the switch node module 3. The test operation principle is the same as that of F1.
[0097] When the fault occurs at F4, the A-phase output terminal A3, B-phase output terminal B3, and C-phase output terminal C3 of the first three-phase output terminal of the current trigger module are connected to the A-phase terminal A2, B-phase terminal B2, and C-phase terminal C2 of the second three-phase terminal of the switch node module 4. The test operation principle is the same as that of F1.
[0098] When the fault occurs at F5, the A-phase output terminal A3, B-phase output terminal B3, and C-phase output terminal C3 of the first three-phase output terminal of the current trigger module are connected to the A-phase terminal A2, B-phase terminal B2, and C-phase terminal C2 of the second three-phase terminal of the switch node module 5. The test operation principle is the same as that of F1.
[0099] This application provides a power distribution network protection testing system, which includes a power supply module, a current trigger module, and switch node modules corresponding to the number of distribution automation terminal devices under test. The output terminal of the power supply module is connected to the input terminal of the current trigger module and the first terminal of all switch node modules, respectively, for converting the mains voltage into a three-phase AC voltage and using the three-phase AC voltage to power the current trigger module and all switch node modules. The output terminal of the current trigger module is connected to the second terminal of each switch node module, for outputting an adjustable current signal by adjusting its own resistance value. Each switch node module is connected to one distribution automation terminal device under test, for simulating fault types using the adjustable current signal and performing distribution network protection function tests on the corresponding distribution automation terminal device under test. This application adopts a modular design of power supply modules, current trigger modules, and switch node modules. The structure is clear, facilitating installation, maintenance, and upgrades. Each module functions independently and can be optimized or replaced accordingly, reducing system complexity and maintenance costs. The current trigger module outputs an adjustable current signal by adjusting its own resistance value, enabling it to simulate currents of different intensities and characteristics. This provides a foundation for simulating various fault types, allowing the test system to more comprehensively and accurately simulate various fault conditions that may occur in the distribution network, improving the comprehensiveness and accuracy of the test. Furthermore, the number of switch node modules corresponds to the number of distribution automation terminal devices under test, with each switch node... Each module can be connected to a single power distribution automation terminal device under test (PDD), enabling parallel testing of multiple PPDD devices. This significantly improves testing efficiency and shortens the testing cycle, making it particularly suitable for batch equipment testing scenarios. Simultaneously, each switch node module uses adjustable current signals to simulate fault types, performing power distribution network protection function tests on the corresponding PPDD device. This realistically simulates current changes during power distribution network faults, effectively verifying the reliability and accuracy of the protection functions of the PPDD device. This helps to promptly identify defects in the protection functions of the equipment, improving the safety and reliability of power distribution network operation.
[0100] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.
Claims
1. A power distribution network protection testing system, characterized in that, The system includes a power supply module, a current triggering module, and a switch node module corresponding to the number of power distribution automation terminal devices under test. The output terminal of the power supply module is connected to the input terminal of the current trigger module and the first terminal of all the switching node modules, respectively, to convert the mains voltage into three-phase AC voltage and to use the three-phase AC voltage to power the current trigger module and all the switching node modules. The output terminal of the current trigger module is connected to the second terminal of each switch node module, and is used to output an adjustable current signal by adjusting its own resistance value. Each switch node module is connected to a power distribution automation terminal device under test (PDUT), which uses the adjustable current signal to simulate fault types and perform power distribution network protection function tests on the corresponding PUT.
2. The power distribution network protection testing system according to claim 1, characterized in that, The power module's output terminals include a three-phase output terminal and a neutral output terminal. The first terminal of the switching node module includes a first three-phase terminal. The three-phase output terminals of the power module are connected to the first three-phase terminals of all switching node modules. The neutral output terminal and B-phase output terminal of the power module are respectively connected to the input terminal of the current trigger module. The power module includes a transformer. The primary input terminal of the transformer is connected to the input terminal of the power module. The three-phase terminals of the secondary side of the transformer are respectively connected to the three-phase output terminals. The neutral terminal of the secondary side of the transformer is connected to the neutral output terminal. The transformer is used to convert the mains voltage into a three-phase AC voltage and output the three-phase AC voltage through the three-phase output terminals respectively.
3. The power distribution network protection testing system according to claim 2, characterized in that, The second end of the switching node module includes a second three-phase terminal; the input end of the current trigger module includes a first input terminal and a second input terminal, and the output end of the current trigger module includes a first three-phase output terminal; the first input terminal is connected to the B-phase output terminal of the power supply module, the second input terminal is connected to the neutral line output terminal of the power supply module, and the first three-phase output terminal of the current trigger module is connected to the second three-phase terminal of the switching node module; The current triggering module includes a first resistor, a second resistor, and a third resistor; The first end of the first resistor is connected to the A-phase output terminal of the first three-phase output terminal, and the second end of the first resistor is connected to the first input terminal and the second end of the third resistor, respectively. The first end of the second resistor is connected to the B-phase output terminal of the first three-phase output terminal, and the second end of the second resistor is connected to the second input terminal. The first end of the third resistor is connected to the C-phase output terminal of the first three-phase output terminals.
4. The power distribution network protection testing system according to claim 3, characterized in that, The first resistor, the second resistor, and the third resistor are all adjustable resistors.
5. The power distribution network protection testing system according to claim 1, characterized in that, When there are at least two power distribution automation terminal devices under test, the system includes at least two switch node modules; At least two switch node modules are connected in series in sequence; and the first end of the first switch node module is connected to the output end of the power supply module, and the second end of each switch node module is connected to the output end of the current trigger module.
6. The power distribution network protection testing system according to claim 1, characterized in that, When there are at least three power distribution automation terminal devices under test, the system includes at least three switch node modules; At least three switch node modules are connected in a tree structure; and the first end of the first-level switch node module is connected to the output end of the power supply module, and the second end of each switch node module is connected to the output end of the current trigger module.
7. The power distribution network protection testing system according to claim 1, characterized in that, Each switch node module includes a relay switch, a current transformer, a voltage acquisition unit, and a switching device; The relay switch is installed between the first and second ends of each switch node module and is used to control the continuity of the line between the first and second ends of each switch node module. The first end of the current transformer is connected to the second end of the relay switch and the corresponding switch node module, and the second end of the current transformer is connected to the corresponding power distribution automation terminal under test. The voltage acquisition unit is connected to the first and second terminals of the corresponding switch node module via a line connection, and the second terminal of the voltage acquisition unit is connected to the corresponding power distribution automation terminal equipment under test. The circuit breaker and switch-opening device is connected to each relay switch and each power distribution automation terminal device under test, respectively, to obtain the circuit breaker and switch-opening commands fed back by each power distribution automation terminal device under test when a fault occurs, and to control the corresponding relay switch to open or close according to the circuit breaker and switch-opening commands.
8. The power distribution network protection testing system according to claim 7, characterized in that, Each switch node module has a first three-phase terminal at its first end and a second three-phase terminal at its second end. The relay switch includes a first relay switch, a second relay switch, and a third relay switch, which are linked together. The first terminal of the first relay switch is connected to the A-phase terminal of the first three-phase terminal, and the second terminal of the first relay switch is connected to the first terminal of the current transformer and the A-phase terminal of the second three-phase terminal, respectively. The first terminal of the second relay switch is connected to the B-phase terminal of the first three-phase terminal, and the second terminal of the second relay switch is connected to the first terminal of the current transformer and the B-phase terminal of the second three-phase terminal, respectively. The first terminal of the third relay switch is connected to the C-phase terminal of the first three-phase terminal, and the second terminal of the third relay switch is connected to the first terminal of the current transformer and the C-phase terminal of the second three-phase terminal, respectively.
9. The power distribution network protection testing system according to claim 8, characterized in that, The current transformer includes a first current transformer, a second current transformer, and a third current transformer; The first end of the first current transformer is connected to the second end of the first relay switch and the A-phase end of the second three-phase switch, respectively. The second end of the first current transformer is connected to the A-phase current end of the corresponding power distribution automation terminal device under test. The first end of the second current transformer is connected to the second end of the second relay switch and the B-phase end of the second three-phase terminal, respectively. The second end of the second current transformer is connected to the B-phase current terminal of the corresponding power distribution automation terminal equipment under test. The first end of the third current transformer is connected to the second end of the third relay switch and the C-phase end of the second three-phase terminal, respectively. The second end of the third current transformer is connected to the C-phase current terminal of the corresponding power distribution automation terminal equipment under test.
10. The power distribution network protection testing system according to claim 7, characterized in that, The switching device includes a first node, a second node, a third node, a fourth node, a fourth resistor, and a fifth resistor; The first end of the first node, the first end of the second node, the first end of the third node, and the first end of the fourth node are connected in parallel and then connected to the relay switch; The first end of the first node is connected to the second end through the fourth resistor, and the first end of the second node is connected to the second end through the fifth resistor; The second end of the first node is connected to the control opening node of each power distribution automation terminal device under test; the second end of the second node is connected to the control closing node of each power distribution automation terminal device under test; the second end of the third node is connected to the opening position node of each power distribution automation terminal device under test; and the second end of the fourth node is connected to the closing position node of each power distribution automation terminal device under test.