Auxiliary device for closed-loop transfer of distribution network system

Abstract

The invention relates to an auxiliary device for loop closing transfer of a distribution network system, which comprises a shell, an acquisition module, an analysis module, a display module, an alarm module and an output module are arranged in the shell, and a current transformer jack and a voltage transformer jack are arranged on the shell; a detachable current transformer is externally connected to the current transformer jack, and a detachable voltage transformer is externally connected to the voltage transformer jack; the current transformer is connected with the acquisition module through the current transformer socket; and the voltage transformer is connected with the acquisition module through the voltage transformer socket. According to the method, the problems that for loop-closing transfer of an existing power distribution network system, whether loop-closing transfer can be carried out or not is analyzed and judged mainly through analog simulation calculation, the analysis result has deviation, support cannot be accurately provided for loop-closing transfer, loop-closing transfer failure may be caused, and safe operation of a power grid is affected can be solved.

Description

Technical Field

[0001] The present invention relates to the field of power supply and distribution, and in particular to an auxiliary device for loop closing and power transfer in a distribution network system. Background Art

[0002] Currently, power distribution system loop closing and power transfer are primarily determined through simulation analysis. Simulation is based on a theoretical model of the distribution system. However, there are certain discrepancies between the theoretical model and the actual distribution system. This can lead to biased simulation results, inaccurate support for loop closing and power transfer, and potentially lead to loop closing and power transfer failures, impacting the safe operation of the power grid. Summary of the Invention

[0003] The purpose of the present invention is to provide an auxiliary device for the closed-loop power transfer of a distribution network system, so as to solve the problem that the closed-loop power transfer of the existing power distribution network system mainly uses simulation calculations to analyze and judge whether the closed-loop power transfer is possible. The analysis results may have deviations and cannot accurately provide support for the closed-loop power transfer, which may lead to the failure of the closed-loop power transfer and affect the safe operation of the power grid.

[0004] The technical solution adopted by the present invention to solve the technical problem is: an auxiliary device for loop-closing and power transfer in a distribution network system, comprising a housing, an acquisition module, an analysis module, a display module, an alarm module, and an output module disposed within the housing, and a current transformer connector and a voltage transformer connector disposed on the housing; a detachable current transformer is externally connected to the current transformer connector, and a detachable voltage transformer is externally connected to the voltage transformer connector; the current transformer is connected to the acquisition module via the current transformer connector; and the voltage transformer is connected to the acquisition module via the voltage transformer connector. Two voltage transformers are provided, which are respectively connected to the contact lines on both sides of the contact switch in the fitting loop line, and are used to collect data of the contact lines on both sides of the contact switch; Two current transformers are provided, which are respectively connected to the contact lines on both sides of the contact switch in the fitting loop line, and are used to collect data of the contact lines on both sides of the contact switch; The acquisition module is used to collect the voltage, frequency, phase sequence, phase and current on both sides of the tie switch on the tie line through the current transformer and voltage transformer; The analysis module is used to analyze whether the phase sequence and frequency on both sides of the tie switch are consistent, whether the difference in phase angle is within the set threshold, and whether the difference in voltage is within the set threshold; and analyze whether the fitting loop line can be closed and powered; and send the data collected by the acquisition module and the analysis results to the display module for display, and send the analysis results to the alarm module; and send the data collected by the acquisition module and the analysis results to the output module for external transmission; The display module is connected to the analysis module and is used to receive data transmitted by the analysis module and display in real time the voltage value, frequency, phase sequence, phase, current value, phase angle difference, voltage difference, phase sequence consistency, frequency consistency, loop-closing power supply feasibility, phase angle difference threshold, and voltage difference threshold on both sides of the tie switch; The alarm module is connected to the analysis module and is used to receive the signal transmitted by the analysis module; when receiving the loop-closing supply transfer signal, it sends a loop-closing supply transfer warning signal; when receiving the loop-closing supply transfer signal, it sends a loop-closing supply transfer warning signal; The output module is connected to the analysis module to transmit the voltage value, frequency, phase sequence, phase, current value, phase angle difference, voltage difference, phase sequence consistency, frequency consistency and ring-closing power supply feasibility on both sides of the tie switch.

[0005] In order to provide an analysis method for the feasibility of loop closing and power transfer, when analyzing the feasibility of loop closing and power transfer of the fitting ring line, the analysis module simultaneously analyzes whether the phase sequence on both sides of the interconnecting switch is consistent, whether the frequency is consistent, whether the phase angle difference is within the set threshold, and whether the voltage difference is within the set threshold. When the phase sequence is consistent, the frequency is consistent, the phase angle difference is within the set threshold, and the voltage difference is within the set threshold, it is determined that the loop closing and power transfer can be carried out, and a loop closing and power transfer signal is sent to the display module and the alarm module; otherwise, it is determined that the loop closing and power transfer cannot be carried out, and a loop closing and power transfer cannot be carried out signal is sent to the display module and the alarm module.

[0006] In order to provide a method for analyzing the feasibility of loop-closing power transfer, the analysis module analyzes the feasibility of loop-closing power transfer of the fitting ring line, including the following steps: Step (1) analyzes whether the phase sequences on both sides of the tie switch are consistent. If they are consistent, proceed to step (2). If they are inconsistent, send a signal indicating that the loop cannot be closed and the supply cannot be switched to the display module and the alarm module, and terminate the analysis. Step (2) analyzes whether the frequencies on both sides of the tie switch are consistent; if they are consistent, proceed to step (3); if they are inconsistent, send a signal indicating that the loop cannot be closed and the supply cannot be switched to the display module and the alarm module, and terminate the analysis; Step (3): Analyze whether the phase angle difference between the two sides of the tie switch is within the set threshold; if it is within the set threshold, go to step (4); if it exceeds the threshold, send a signal indicating that the loop cannot be closed and the supply cannot be switched to the display module and the alarm module, and terminate the analysis; Step (4) analyzes whether the voltage difference between the two sides of the tie switch is within the set threshold; if it is within the set threshold, it is determined that the loop can be closed and the supply can be transferred, and a loop closing and supply transfer signal is sent to the display module and the alarm module; otherwise, it is determined that the loop cannot be closed and the supply cannot be transferred, and a loop closing and supply transfer signal is sent to the display module and the alarm module.

[0007] In order to provide a feasibility analysis method for closed-loop power transfer, the auxiliary device for closed-loop power transfer in the distribution network system also includes a data input module connected to the analysis module; the data input module is used for the operator to input data; when the analysis module makes a judgment, the impedance of the fitting loop, the current carrying capacity of each device, and the protection setting value of the protection device of each device are first input through the data input module. The analysis module calculates the three-phase current circulating current value of the fitting loop interconnection line according to the impedance of the fitting loop, which is defined as A; the minimum current carrying capacity is defined as B; the protection setting value of the protection device of the device is defined as C; when A is less than B, and A is less than When it is C, it is determined that the loop can be closed and the supply can be transferred, and a loop closing and supply transfer signal is sent to the display module and the alarm module; when A is less than B and A is greater than C, a prompt signal is sent to the display module and the alarm module, and a manual determination is made whether to close the loop and transfer the supply; when A is greater than or equal to B and A is greater than or equal to C, it is determined that the loop cannot be closed and the supply cannot be transferred, and a loop closing and supply transfer signal is sent to the display module and the alarm module to warn; if the loop can be closed and the supply can be transferred, after the loop is closed and the supply is transferred, the analysis module calculates the three-phase current circulation value and voltage waveform of the loop after closing, and transmits them to the output module, and the output module transmits the collected loop current and voltage waveform to the outside.

[0008] The beneficial effects of the present invention are as follows: 1. By using the data collected in real time as the data support for the closed-loop power supply analysis, the data source is more accurate and reliable, and the credibility of the analysis results is higher compared to the simulation analysis based on the theoretical model of the distribution network system. At the same time, the real-time analysis is more timely than the simulation. It can effectively solve the problem of closed-loop power supply of the existing distribution network system, which mainly uses simulation calculations to analyze and judge whether the closed-loop power supply can be carried out. The analysis results will have deviations and cannot accurately provide support for the closed-loop power supply, which may cause the closed-loop power supply to fail and affect the safe operation of the power grid.

[0009] 2. The analysis is based on the impedance of the loop to be closed, the current carrying capacity of each device, and the protection settings of each device's protection device. The analysis is directly based on the device parameters. The analysis results are directly related to the stable operation of the equipment, which can reduce the impact of the closing and power supply on the equipment.

[0010] 3. First, determine the phase sequence. If the phase sequence is inconsistent, it can be directly determined that the loop cannot be closed and the power supply cannot be transferred. This can reduce analysis costs and improve analysis efficiency.

[0011] 4. Add frequency analysis to quickly identify whether the fitting loop lines are in the same power supply system; improve the efficiency of loop closing judgment, which can be used for loop closing and power transfer in different power supply systems, expanding the scope of application.

[0012] 5. When used for loop-closing power transfer in different power supply systems, since the phase angle difference is a variable, by setting the phase angle difference threshold, it is possible to choose to perform loop-closing power transfer when the phase angle difference is appropriate, thereby improving the safety of loop-closing power transfer and providing technical support for loop-closing power transfer in different power supply systems.

[0013] 6. The determination of phase sequence, frequency, phase angle difference and voltage difference can provide all-round and reliable data support for ring closing and power supply, reduce the risk of incorrect ring closing operation and improve the safety of ring closing and power supply.

[0014] The present invention will be described in more detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the present invention.

[0016] Among them, 1. Shell, 2. Acquisition module, 3. Analysis module, 4. Display module, 5. Alarm module, 6. Output module, 7. Data input module, 8. Current transformer socket, 9. Voltage transformer socket, 10. Current transformer, 11. Voltage transformer, 12. Interconnection line, 13. Interconnection switch, 14. First substation, 15. Second substation. DETAILED DESCRIPTION

[0017] Example 1, as Figure 1 The auxiliary device for loop-closing and power transfer in a distribution network system shown in the figure includes a housing 1, within which are disposed a collection module 2, an analysis module 3, a display module 4, an alarm module 5, and an output module 6. The housing 1 is provided with a current transformer connector 8 and a voltage transformer connector 9. The current transformer connector 8 is externally connected to a detachable current transformer 10, and the voltage transformer connector 9 is externally connected to a detachable voltage transformer 11. The current transformer 10 is connected to the collection module 2 via the current transformer connector 8; the voltage transformer 11 is connected to the collection module 2 via the voltage transformer connector 9. Two voltage transformers 11 are provided, which are respectively connected to the tie lines 12 on both sides of the tie switch 13 in the fitting loop line, and are used to collect data of the tie lines 12 on both sides of the tie switch 13; the fitting loop line includes a first substation 14, a second substation 15, the tie line 12, and the tie switch 13; Two current transformers 10 are provided, which are respectively connected to the contact lines 12 on both sides of the contact switch 13 in the fitting loop circuit; and are used to collect data of the contact lines 12 on both sides of the contact switch 13; The acquisition module 2 is used to collect the voltage, frequency, phase sequence, phase, and current on both sides of the tie switch 13 on the tie line 12 through the current transformer 10 and the voltage transformer 11; The analysis module 3 is used to determine whether the phase sequence and frequency on both sides of the tie switch 13 in the fitting loop line are consistent, whether the difference in phase angle is within the set threshold, and whether the difference in voltage is within the set threshold; and analyze whether the fitting loop line can be closed and powered; and send the data collected by the acquisition module 2 and the analysis results to the display module 4 for display, and send the analysis results to the alarm module 5; and send the data collected by the acquisition module 2 and the analysis results to the output module 6 for external transmission; The threshold value of the phase angle difference and the threshold value of the voltage difference are selected and set as needed; The display module 4 is connected to the analysis module 3 and is used to receive data transmitted by the analysis module 3, and to display in real time the voltage value, frequency, phase sequence, phase, current value, phase angle difference difference, voltage difference difference, phase sequence consistency, frequency consistency, and loop-closing power supply feasibility of the tie switch 13 on both sides of the fitting loop line; the housing 1 is provided with a touch screen connected to the display module 4, which can display data and judgment results through the touch screen and perform corresponding operations. The specific touch operation function can be set as needed. The specific setting does not belong to the innovation of the present invention. Those skilled in the art can freely play according to the existing technology, so no further explanation is given; The alarm module 5 is connected to the analysis module 3 and is used to receive the signal transmitted by the analysis module 3; when a signal of loop closure and supply transfer is received, a warning signal of loop closure and supply transfer is issued; when a signal of non-loop closure and supply transfer is received, a warning signal of non-loop closure and supply transfer is issued; the housing 1 is provided with a group of warning lights connected to the alarm module 5, and the specific number and color changes can be flexibly selected according to needs; The output module 6 is connected to the analysis module 3 and is used to transmit the voltage value, frequency, phase sequence, phase, current value, phase angle difference, voltage difference, phase sequence consistency, frequency consistency and loop-to-loop power supply feasibility on both sides of the tie switch 13; the output module 6 integrates a communication module for external communication transmission of data; The housing 1 is also provided with a corresponding operation interface and operation buttons.

[0018] Example 2, based on an auxiliary device for loop closing and power transfer of a distribution network system in Example 1, when the analysis module 3 analyzes the feasibility of loop closing and power transfer of the fitting ring line, it also analyzes whether the phase sequence on both sides of the connecting switch 13 is consistent, whether the frequency is consistent, whether the phase angle difference is within the set threshold, and whether the voltage difference is within the set threshold. When the phase sequence is consistent, the frequency is consistent, the phase angle difference is within the set threshold, and the voltage difference is within the set threshold, it is determined that the loop can be closed and the loop can be closed and the power transfer signal is sent to the display module 4 and the alarm module 5; otherwise, it is determined that the loop cannot be closed, and a loop cannot be closed and power transfer signal is sent to the display module 4 and the alarm module 5.

[0019] Example 3, based on an auxiliary device for loop-closing and power transfer in a distribution network system in Example 1, the analysis module 3 analyzes the feasibility of loop-closing and power transfer of the fitting ring line, including the following steps: Step (1) determines whether the phase sequences on both sides of the tie switch 13 in the fitting loop circuit are consistent. If they are consistent, proceed to step (2). If they are inconsistent, a signal indicating that the loop cannot be closed and the supply cannot be switched is sent to the display module 4 and the alarm module 5, and the analysis is terminated. Step (2) determines whether the frequencies on both sides of the tie switch 13 are consistent; if they are consistent, proceed to step (3); if they are inconsistent, a signal indicating that the loop cannot be closed and the supply cannot be switched is sent to the display module 4 and the alarm module 5, and the analysis is terminated; Step (3) determines whether the phase angle difference between the two sides of the tie switch 13 is within the set threshold; if it is within the set threshold, go to step (4); if it exceeds the threshold, send a signal indicating that the loop cannot be closed and the supply cannot be switched to the display module 4 and the alarm module 5, and terminate the analysis; Step (4) determines whether the voltage difference between the two sides of the interconnecting switch 13 is within the set threshold value; if it is within the set threshold value, it is determined that the loop can be closed and the supply can be transferred, and a loop closing and supply transfer signal is sent to the display module 4 and the alarm module 5; otherwise, it is determined that the loop cannot be closed, and a loop closing and supply transfer signal is sent to the display module 4 and the alarm module 5.

[0020] Example 4, based on Example 1, is an auxiliary device for loop-closing and power transfer in a distribution network system, further comprising a data input module 7 connected to the analysis module 3; the data input module 7 is used for an operator to input data; data input can be achieved through a touch screen display or through an integrated communication module, and data input can be performed remotely through the communication module. The data input method does not constitute the innovation of the present invention, and those skilled in the art can select it according to needs and in combination with existing technologies. No further explanation is given here. When the analysis module 3 performs the feasibility analysis of the closing and supplying of the fitting loop line, the impedance of the fitting loop, the current carrying capacity of each device, and the protection setting value of the protection device of each device are first input through the data input module 7. The analysis module 3 calculates the three-phase current circulating value of the fitting loop interconnection line 12 according to the impedance of the fitting loop, and defines it as A; defines the minimum current carrying capacity as B; and defines the protection setting value of the protection device of the device as C; when A is less than B, and A is less than C, it is determined that the loop can be closed and the loop can be closed and the supply signal is sent to the display module 4 and Alarm module 5; when A is less than B and A is greater than C, a prompt signal is sent to display module 4 and alarm module 5, and a manual determination is made whether to close the loop and transfer the power supply; when A is greater than or equal to B and A is greater than or equal to C, it is determined that the loop closing and transfer of power supply is not possible, and an alarm signal is sent to display module 4 and alarm module 5 to issue an alarm; if the loop closing and transfer of power supply is possible, after the loop closing and transfer of power supply, analysis module 3 calculates the three-phase current circulating value and voltage waveform of the loop after the loop closing and transmits them to output module 6, which transmits the collected loop current and voltage waveforms to the outside. Data input module 7 is also connected to display module 4, and the data module displays the input data. Housing 1 is provided with a numerical control display screen, through which data is input.

[0021] In the description of the present invention, it should be understood that the terms "center", "lateral", "up", "down", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more. In addition, the term "including" and any variations thereof are intended to cover non-exclusive inclusions.

[0022] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0023] The terms used herein are intended only to describe specific embodiments and are not intended to limit exemplary embodiments. Unless the context clearly indicates otherwise, the singular forms "a", "an", "an item" used herein are also intended to include the plural. It should also be understood that the terms "comprise" and / or "include" used herein specify the presence of stated features, integers, steps, operations, units and / or components, and do not preclude the presence or addition of one or more other features, integers, steps, operations, units, components and / or combinations thereof.

[0024] The present invention has been described above with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described method. Any non-substantial improvements made using the method concepts and technical solutions of the present invention, or any direct application of the above-described concepts and technical solutions to other situations without modification, fall within the scope of protection of the present invention.

Claims

1. An auxiliary device for closing and transferring power in a distribution network system, comprising a housing, characterized in that: The housing is provided with a collection module, an analysis module, a display module, an alarm module, and an output module. The housing is provided with a current transformer connector and a voltage transformer connector. The current transformer connector is externally connected to a detachable current transformer, and the voltage transformer connector is externally connected to a detachable voltage transformer. The current transformer is connected to the collection module via the current transformer connector; the voltage transformer is connected to the collection module via the voltage transformer connector. Two voltage transformers are provided, which are respectively connected to the contact lines on both sides of the contact switch in the fitting loop line, and are used to collect data of the contact lines on both sides of the contact switch; Two current transformers are provided, which are respectively connected to the contact lines on both sides of the contact switch in the fitting loop line, and are used to collect data of the contact lines on both sides of the contact switch; The acquisition module is used to collect the voltage, frequency, phase sequence, phase, and current on both sides of the tie switch on the tie line through the current transformer and the voltage transformer; The analysis module is used to analyze whether the phase sequence on both sides of the tie switch is consistent, whether the frequency is consistent, whether the difference in phase angle is within the set threshold, and whether the difference in voltage difference is within the set threshold; And analyze whether the fitted loop line can be closed and transferred; The data collected by the acquisition module and the analysis results are sent to the display module for display, and the analysis results are sent to the alarm module; the data collected by the acquisition module and the analysis results are sent to the output module for external transmission; The display module is connected to the analysis module, and is used to receive data transmitted by the analysis module, and to display in real time the voltage value, frequency, phase sequence, phase, current value, phase angle difference difference, voltage difference difference, phase sequence consistency, frequency consistency, feasibility of closed-loop power supply, phase angle difference difference threshold, and voltage difference difference threshold on both sides of the tie switch; The alarm module is connected to the analysis module and is used to receive the signal transmitted by the analysis module; when receiving the signal that the loop can be closed and the supply can be switched, it sends out the early warning signal that the loop can be closed and the supply can be switched; when receiving the signal that the loop cannot be closed and the supply can be switched, it sends out the alarm signal that the loop cannot be closed and the supply can be switched; The output module is connected to the analysis module to transmit the voltage value, frequency, phase sequence, phase, current value, phase angle difference, voltage difference, phase sequence consistency, frequency consistency and ring-closing power supply feasibility on both sides of the tie switch.

2. The auxiliary device for the closed-loop power transfer of the distribution network system according to claim 1 is characterized in that: When the analysis module analyzes the feasibility of closing the loop and transferring power of the fitting ring line, it also analyzes whether the phase sequence on both sides of the interconnecting switch is consistent, whether the frequency is consistent, whether the phase angle difference is within the set threshold, and whether the voltage difference is within the set threshold. When the phase sequence is consistent, the frequency is consistent, the phase angle difference is within the set threshold, and the voltage difference is within the set threshold, it is determined that the loop can be closed and the power can be transferred, and a signal of closing the loop and transferring power is sent to the display module and the alarm module; otherwise, it is determined that the loop cannot be closed and the power cannot be closed and the signal of closing the loop and transferring power is sent to the display module and the alarm module.

3. The auxiliary device for the closed-loop power transfer of the distribution network system according to claim 1 is characterized in that: When the analysis module analyzes the feasibility of the closed loop power supply of the fitted loop line, the following steps are included: Step (1), analyzing whether the phase sequences on both sides of the tie switch are consistent. If they are consistent, proceed to step (2). If they are inconsistent, a signal indicating that the loop cannot be closed and the supply cannot be switched is sent to the display module and the alarm module, and the analysis is terminated. Step (2), analyzing whether the frequencies on both sides of the tie switch are consistent; if they are consistent, proceed to step (3); if they are inconsistent, a signal indicating that the loop cannot be closed and the supply cannot be switched is sent to the display module and the alarm module, and the analysis is terminated; Step (3), analyzing whether the phase angle difference between the two sides of the tie switch is within the set threshold; if it is within the set threshold, proceed to step (4); if it exceeds the threshold, a signal indicating that the loop cannot be closed and the supply cannot be switched is sent to the display module and the alarm module, and the analysis is terminated; Step (4), analyzing whether the voltage difference between the two sides of the tie switch is within the set threshold; if it is within the set threshold, it is determined that the loop can be closed and the supply can be transferred, and a loop closing and supply transfer signal is sent to the display module and the alarm module; otherwise, it is determined that the loop cannot be closed and the supply cannot be transferred, and a loop closing and supply transfer signal is sent to the display module and the alarm module.

4. The auxiliary device for the closed-loop power transfer of the distribution network system according to claim 1 is characterized in that: It also includes a data input module connected to the analysis module; the data input module is used for operators to input data; when the analysis module makes a judgment, the impedance of the fitting loop, the current carrying capacity of each device, and the protection setting value of the protection device of each device are first input through the data input module, and the analysis module calculates the three-phase current circulating value of the interconnection line to be closed according to the impedance of the fitting loop, which is defined as A; the minimum current carrying capacity is defined as B; the protection setting value of the protection device of the equipment is defined as C; when A is less than B, and A is less than C, it is determined that the loop can be closed and the power supply can be transferred, and a closeable signal is issued. The loop supply signal is sent to the display module and the alarm module; when A is less than B and A is greater than C, a prompt signal is sent to the display module and the alarm module, and a manual judgment is made whether to close the loop and transfer the supply; when A is greater than or equal to B and A is greater than or equal to C, it is determined that the loop cannot be closed and the supply cannot be closed, and a signal is sent to the display module and the alarm module to warn; if the loop can be closed and the supply can be closed, after the loop is closed and the supply is closed, the analysis module calculates the three-phase current circulation value and voltage waveform of the loop after the loop is closed, and transmits them to the output module, and the output module transmits the collected loop current and voltage waveform to the outside.

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