Low-voltage line fault indicator and overload, over-temperature and fault generation and positioning identification method

Abstract

The invention relates to the technical field of low-voltage power distribution network fault diagnosis, and discloses a low-voltage line fault indicator and an overload, over-temperature, fault occurrence and positioning identification method. The low-voltage line fault indicator comprises an acquisition module, a shell, a control module and an indicating device; the indicating device and the acquisition module are both connected with the control module; the acquisition module comprises a current transformer, a voltage transformer and a temperature sensor; the shell comprises a plastic shell body and a wire clamp; the acquisition module and the control module are arranged in the plastic shell; the wire clamp is arranged on one surface of the plastic shell; the sensing ends of the current transformer, the voltage transformer and the temperature sensor are arranged on one surface of the plastic shell on which the wire clamp is positioned; and the indicating device is arranged on one surface, different from the wire clamp, of the plastic shell. The method solves the problem that the prior art is not suitable for a low-voltage distribution network, and has the characteristics of simplicity, practicability and low price.

Description

Technical Field

[0001] The present invention relates to the technical field of low-voltage distribution network fault diagnosis, and more specifically, to a low-voltage line fault indicator and an overload, overtemperature, fault occurrence and location identification method. Background Art

[0002] The construction of low-voltage distribution network transparency is one of the key tasks of distribution network construction in recent years. In recent years, my country's distribution network has gradually shown the characteristics of "medium voltage is basically transparent, low voltage pilot transparency", but there is still a certain gap in achieving low voltage transparency. Among them, the discovery and troubleshooting of low-voltage line faults still rely on manual inspections and manual detection with tools such as shaking meters. There is a lack of auxiliary troubleshooting methods for production equipment, and efficient judgment of faulty line sections has not been achieved.

[0003] The judgment of the fault section in the medium-voltage distribution network mainly relies on the fault indicator. By judging whether the sudden change of current flowing through the line or the magnitude of the zero-sequence current exceeds the set value within a period of time, it is determined whether the line is flowing with a fault current. Then, the section where the faulty line is located is determined according to the feeder topology, which greatly improves the fault finding efficiency of the repair personnel.

[0004] The prior art provides a power line fault alarm device and method thereof, which relate to the technical field of alarm devices and include a line fault indicator, wherein the line fault indicator includes a current sensor, a voltage sensor, a processing chip and a wireless module.

[0005] However, the existing fault indicator technology is not suitable for low-voltage distribution networks. Therefore, how to invent a low-voltage line fault indicator is a technical problem that urgently needs to be solved in this technical field. Summary of the invention

[0006] In order to solve the problem that the prior art is not applicable to low-voltage distribution networks, the present invention provides a low-voltage line fault indicator and an overload, overtemperature, fault occurrence and location identification method, which is simple, practical and inexpensive.

[0007] In order to achieve the above-mentioned purpose of the present invention, the technical scheme adopted is as follows:

[0008] A low-voltage line fault indicator comprises a collection module, a housing, a control module and an indication device; the indication device and the collection module are both connected to the control module;

[0009] The acquisition module includes a current transformer, a voltage transformer, and a temperature sensor;

[0010] The shell comprises a plastic shell and a wire clamp;

[0011] The acquisition module and the control module are both arranged in a plastic housing;

[0012] The wire clamp is arranged on one side of the plastic shell; the sensing ends of the current transformer, voltage transformer and temperature sensor are all arranged on one side of the plastic shell where the wire clamp is located;

[0013] The indicating device is arranged on a side of the plastic shell which is different from the wire clamp.

[0014] Preferably, the current transformer is a Rogowski coil; and the voltage transformer is a Hall voltage transformer.

[0015] Furthermore, it also includes a storage module, a power management module, and a carrier communication module; the storage module, the power management module, and the carrier communication module are all arranged in a plastic shell and connected to the control module.

[0016] Furthermore, the storage module is used to store historical fault information, including flash memory and electrically erasable programmable read-only memory; the power management module is used to supply power to all modules, including a main power unit, a backup power unit and a switching unit; the carrier communication module is used for data communication, including a power line communication chip.

[0017] Furthermore, the main power supply unit cooperates with the current transformer to realize induction of power from the low-voltage line and supply it to the various components of the low-voltage line fault indicator; the backup power supply unit is a supercapacitor; the switching unit controls the switching of the main power supply unit and the backup power supply unit. Under normal circumstances, the main power supply unit works to supply power to the low-voltage line fault indicator; when the low-voltage line is out of power, the backup power supply unit supplies power; the indicating device is specifically an indicator light.

[0018] Furthermore, the plastic shell is divided into an upper shell and a lower shell, and the shell also includes a torsion spring and a locking structure; the upper and lower sides of the locking structure are respectively arranged on the same side of the upper shell and the lower shell, and the upper shell and the lower shell are movably connected through the locking structure; the two ends of the torsion spring are arranged on the other side of the upper shell and the lower shell.

[0019] An overload identification method, based on the low-voltage line fault indicator, comprises the following specific steps:

[0020] Install the low-voltage line fault indicator on the low-voltage line through a line clamp;

[0021] The rated current is set on the low-voltage line fault indicator through the control module, and the current transformer collects the low-voltage line load current information at the set time interval;

[0022] Determine whether the load current is greater than the set rated current threshold and whether the duration is greater than the set time;

[0023] If both judgment conditions are true, the current low-voltage line is in an overload state, and an overload alarm is output. If at least one judgment condition is false, no action is taken.

[0024] An over-temperature identification method, based on the low-voltage line fault indicator, comprises the following specific steps:

[0025] Install the low-voltage line fault indicator on the low-voltage line through a line clamp;

[0026] The low-voltage line warning temperature is set on the low-voltage line fault indicator through the control module, and the low-voltage line temperature information is collected at the set time interval;

[0027] Determine whether the low-voltage line temperature is greater than the warning temperature and the duration is greater than the set time;

[0028] If both judgment conditions are true, the current low-voltage line is in an over-temperature state and an over-temperature alarm is output; if at least one judgment condition is false, no action is taken.

[0029] A method for identifying a fault occurrence, based on the low-voltage line fault indicator, comprises the following specific steps:

[0030] Install the low-voltage line fault indicator on the low-voltage line through a line clamp;

[0031] Setting the low-voltage line fault starting current and voltage on the low-voltage line fault indicator through the control module, and collecting the low-voltage line voltage and current information at the set time interval;

[0032] Determine whether the low-voltage line current meets the following conditions: the line current is greater than the fault starting current, the duration is greater than the designed time, and the line voltage is less than the fault starting voltage;

[0033] If all three judgment conditions are true, a fault alarm is output; if at least one judgment condition is false, no action is taken.

[0034] A fault location and identification method, based on the low-voltage line fault indicator, comprises the following specific steps:

[0035] Under the broadband carrier low-voltage substation, the substation distribution transformer terminal obtains the low-voltage line topology, installs a number of low-voltage line fault indicators on each low-voltage line in the substation, and enters the installation point locations into the substation distribution transformer terminal to obtain a fault indicator location map based on the low-voltage line topology;

[0036] Determine whether the fault indicators of each low-voltage line in the substation area have a fault alarm;

[0037] If the judgment condition is yes, the corresponding fault icon will be marked on the fault indicator location map, and the fault location will be pushed to the relevant operation and maintenance personnel. If not, no action will be taken.

[0038] The beneficial effects of the present invention are as follows:

[0039] The present invention provides a low-voltage line fault indicator and identification method, comprising an acquisition module, a housing, a control module, and an indicating device. The present invention provides a current transformer, a voltage transformer, and a temperature sensor in the acquisition module, and adopts a housing including a plastic housing and a wire clamp. The low-voltage line has high temperature, overload, and fault alarm functions, can correctly determine the section location of the low-voltage line fault, can improve the low-voltage line fault repair efficiency and reduce the power restoration time, and achieves the purpose of improving the low-voltage power supply reliability and promoting the transparent construction of the low-voltage distribution network. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a system diagram of a low voltage line fault indicator of the present invention;

[0041] Figure 2 It is a structural schematic diagram of a low-voltage line fault indicator of the present invention;

[0042] Figure 3 is a flow chart of the overload identification method.

[0043] Figure 4 It is a flow chart of the over-temperature identification method.

[0044] Figure 5 It is a flow chart of the fault occurrence identification method.

[0045] Figure 6 It is a flow chart of the fault location and identification method.

[0046] In the figure, 1 is a plastic shell, 2 is a wire clamp, 3 is a torsion spring, 4 is a lock structure, and 5 is an indicator light. DETAILED DESCRIPTION

[0047] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0048] Example 1

[0049] like Figure 1 As shown, a low-voltage line fault indicator includes a collection module, a housing, a control module, and an indication device; the indication device and the collection module are both connected to the control module;

[0050] The acquisition module includes a current transformer, a voltage transformer, and a temperature sensor;

[0051] The shell comprises a plastic shell 1 and a wire clamp 2;

[0052] The acquisition module and the control module are both arranged in the plastic housing 1;

[0053] The wire clamp 2 is arranged on one side of the plastic housing 1; the sensing ends of the current transformer, voltage transformer and temperature sensor are all arranged on one side of the plastic housing 1 where the wire clamp 2 is located;

[0054] The indicating device is arranged on a side of the plastic housing 1 which is different from the wire clamp 2 .

[0055] In a specific embodiment, the current transformer is a Rogowski coil; and the voltage transformer is a Hall voltage transformer.

[0056] In a specific embodiment, it also includes a storage module, a power management module, and a carrier communication module; the storage module, the power management module, and the carrier communication module are all arranged in the plastic housing 1 and connected to the control module.

[0057] In a specific embodiment, the storage module is used to store historical fault information, including flash memory and electrically erasable programmable read-only memory; the power management module is used to supply power to all modules, including a main power unit, a backup power unit and a switching unit; the carrier communication module is used for data communication, including a power line communication chip.

[0058] In a specific embodiment, the main power supply unit cooperates with the current transformer to realize induction of power from the low-voltage line and supply it to the various components of the low-voltage line fault indicator; the backup power supply unit is a supercapacitor; the switching unit controls the switching of the main power supply unit and the backup power supply unit. Under normal circumstances, the main power supply unit works to supply power to the low-voltage line fault indicator; when the low-voltage line is out of power, the backup power supply unit supplies power; the indicating device is specifically an indicator light 5.

[0059] In this embodiment, the temperature sensor has a low-voltage line temperature sampling function; the judgment module has a numerical value determination and a timer function, which can be used to judge the current, voltage and temperature data size of the low-voltage line, and can also be used to judge the duration of the signal; the carrier communication module can enable the low-voltage line fault indicator to communicate with the substation distribution terminal.

[0060] In this embodiment, the indicator light 5 can present different flashing states according to the alarm state of the low-voltage line fault indicator. In the high temperature alarm state, the indicator light 5 flashes once every six seconds for one hour; in the overload alarm state, the indicator light 5 flashes once every three seconds for one hour; in the fault alarm state, the indicator light 5 flashes once every second for ten minutes.

[0061] In this embodiment, the plastic shell 1 adopts three colors: yellow, green and red. When a yellow plastic shell 1 is used, it indicates that it is used for phase A of the low-voltage line; when a green plastic shell 1 is used, it indicates that it is used for phase B of the low-voltage line; when a red plastic shell 1 is used, it indicates that it is used for phase C of the low-voltage line.

[0062] In a specific embodiment, the plastic shell 1 is divided into an upper shell and a lower shell, and the shell also includes a torsion spring 3 and a locking structure 4; the upper and lower sides of the locking structure 4 are respectively arranged on the same side of the upper shell and the lower shell, and the upper shell and the lower shell are movably connected through the locking structure 4; the two ends of the torsion spring 3 are arranged on the other side of the upper shell and the lower shell.

[0063] Example 2

[0064] like Figure 3 As shown, an overload identification method, based on the low-voltage line fault indicator, includes the following specific steps:

[0065] Install the low-voltage line fault indicator on the low-voltage line through the line clamp 2;

[0066] The rated current is set on the low-voltage line fault indicator through the control module, and the current transformer collects the low-voltage line load current information at the set time interval;

[0067] Determine whether the load current is greater than 1.2 times the rated current and lasts for more than 5 minutes;

[0068] If both judgment conditions are true, the current low-voltage line is in an overload state, and an overload alarm is output. If at least one judgment condition is false, no action is taken.

[0069] Example 3

[0070] like Figure 4 As shown, an over-temperature identification method, based on the low-voltage line fault indicator, includes the following specific steps:

[0071] Install the low-voltage line fault indicator on the low-voltage line through the line clamp 2;

[0072] The low-voltage line warning temperature is set on the low-voltage line fault indicator through the control module, and the low-voltage line temperature information is collected at the set time interval;

[0073] Determine whether the low-voltage line temperature is greater than the warning temperature and lasts for more than 5 minutes;

[0074] If both judgment conditions are true, the current low-voltage line is in an over-temperature state and an over-temperature alarm is output; if at least one judgment condition is false, no action is taken.

[0075] Example 4

[0076] like Figure 5 As shown, a method for identifying a fault occurrence, based on the low-voltage line fault indicator, comprises the following specific steps:

[0077] Install the low-voltage line fault indicator on the low-voltage line through the line clamp 2;

[0078] Setting the low-voltage line fault starting current and voltage on the low-voltage line fault indicator through the control module, and collecting the low-voltage line voltage and current information at the set time interval;

[0079] Determine whether the low-voltage line current meets the following conditions: the line current is greater than the fault starting current, the duration is greater than 0.1 seconds, and the line voltage is less than the fault starting voltage;

[0080] If all three judgment conditions are true, a fault alarm is output; if at least one judgment condition is false, no action is taken.

[0081] Example 5

[0082] like Figure 6 As shown, a fault location and identification method, based on the low-voltage line fault indicator, includes the following specific steps:

[0083] Under the broadband carrier low-voltage substation, the substation distribution transformer terminal obtains the low-voltage line topology, installs a number of low-voltage line fault indicators on each low-voltage line in the substation, and enters the installation point locations into the substation distribution transformer terminal to obtain a fault indicator location map based on the low-voltage line topology;

[0084] Determine whether the fault indicators of each low-voltage line in the substation area have a fault alarm;

[0085] If the judgment condition is yes, the corresponding fault icon will be marked on the fault indicator location map, and the fault location will be pushed to the relevant operation and maintenance personnel. If not, no action will be taken.

[0086] In this embodiment, in the broadband carrier low-voltage substation, each electric meter in the substation is installed with a broadband carrier chip. The substation distribution transformer terminal can obtain the low-voltage line topology map of the substation based on the broadband carrier signal provided by the electric meter. On this basis, the installation location information of the low-voltage line fault indicator is entered and the specific location of the low-voltage line fault indicator can be displayed on the low-voltage line topology map.

[0087] In this embodiment, when a fault indicator location map based on the low-voltage line topology is formed, the icons of all fault indicators in the initialization substation are white circles. When the fault indicator issues a high temperature alarm, its icon will be changed to yellow. When the fault indicator issues an overload alarm, its icon will be changed to orange. When the fault indicator issues a fault alarm, its icon will be changed to red.

[0088] Obviously, the above embodiments of the present invention are only examples for clearly explaining the present invention, and are not intended to limit the implementation methods of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A low voltage line fault indicator, characterized in that: It includes a collection module, a housing, a control module, and an indication device; the indication device and the collection module are both connected to the control module; The acquisition module includes a current transformer, a voltage transformer, and a temperature sensor; The housing comprises a plastic shell (1) and a wire clamp (2); The acquisition module and the control module are both arranged in the plastic housing (1); The wire clamp (2) is arranged on one side of the plastic housing (1); the sensing ends of the current transformer, voltage transformer and temperature sensor are all arranged on one side of the plastic housing (1) where the wire clamp (2) is located; The indicating device is arranged on a side of the plastic housing (1) which is different from the wire clamp (2).

2. The low voltage line fault indicator according to claim 1, characterized in that: The current transformer is a Rogowski coil; the voltage transformer is a Hall voltage transformer.

3. The low voltage line fault indicator according to claim 1, characterized in that: It also includes a storage module, a power management module, and a carrier communication module; the storage module, the power management module, and the carrier communication module are all arranged in the plastic housing (1) and connected to the control module.

4. The low voltage line fault indicator according to claim 3, characterized in that: The storage module is used to store historical fault information, including flash memory and electrically erasable programmable read-only memory; the power management module is used to supply power to all modules, including a main power unit, a backup power unit and a switching unit; the carrier communication module is used for data communication, including a power line communication chip.

5. The low voltage line fault indicator according to claim 4, characterized in that: The main power supply unit cooperates with the current transformer to realize induction power extraction from the low-voltage line and supply it to various components of the low-voltage line fault indicator; the backup power supply unit is a super capacitor; the switching unit controls the switching between the main power supply unit and the backup power supply unit. Under normal circumstances, the main power supply unit works to supply power to the low-voltage line fault indicator; when the low-voltage line is out of power, the backup power supply unit supplies power; the indicating device is specifically an indicator light (5).

6. The low voltage line fault indicator according to claim 1, characterized in that: The plastic shell (1) is divided into an upper shell and a lower shell, and the shell further comprises a torsion spring (3) and a locking structure (4); the upper side and the lower side of the locking structure (4) are respectively arranged on the same side of the upper shell and the lower shell, and the upper shell and the lower shell are movably connected via the locking structure (4); the two ends of the torsion spring (3) are arranged on the other side of the upper shell and the lower shell.

7. An overload identification method, characterized in that: The low-voltage line fault indicator according to any one of claims 1 to 6 comprises the following specific steps: The low-voltage line fault indicator is installed on the low-voltage line by means of a line clamp (2); The rated current is set on the low-voltage line fault indicator through the control module, and the current transformer collects the low-voltage line load current information at the set time interval; Determine whether the load current is greater than the set rated current threshold and whether the duration is greater than the set time; If both judgment conditions are true, the current low-voltage line is in an overload state, and an overload alarm is output. If at least one judgment condition is false, no action is taken.

8. An over-temperature identification method, characterized in that: The low-voltage line fault indicator according to any one of claims 1 to 6 comprises the following specific steps: The low-voltage line fault indicator is installed on the low-voltage line by means of a line clamp (2); The low-voltage line warning temperature is set on the low-voltage line fault indicator through the control module, and the low-voltage line temperature information is collected at the set time interval; Determine whether the low-voltage line temperature is greater than the warning temperature and the duration is greater than the set time; If both judgment conditions are true, the current low-voltage line is in an over-temperature state and an over-temperature alarm is output; if at least one judgment condition is false, no action is taken.

9. A method for identifying a fault occurrence, characterized in that: The low-voltage line fault indicator according to any one of claims 1 to 6 comprises the following specific steps: The low-voltage line fault indicator is installed on the low-voltage line by means of a line clamp (2); Setting the low-voltage line fault starting current and voltage on the low-voltage line fault indicator through the control module, and collecting the low-voltage line voltage and current information at the set time interval; Determine whether the low-voltage line current meets the following conditions: the line current is greater than the fault starting current, the duration is greater than the designed time, and the line voltage is less than the fault starting voltage; If all three judgment conditions are true, a fault alarm is output; if at least one judgment condition is false, no action is taken.

10. A fault location and identification method, characterized in that: The low-voltage line fault indicator according to any one of claims 1 to 6 comprises the following specific steps: Under the broadband carrier low-voltage substation, the substation distribution transformer terminal obtains the low-voltage line topology, installs a number of low-voltage line fault indicators on each low-voltage line in the substation, and enters the installation point locations into the substation distribution transformer terminal to obtain a fault indicator location map based on the low-voltage line topology; Determine whether the fault indicators of each low-voltage line in the substation area have a fault alarm; If the judgment condition is yes, the corresponding fault icon will be marked on the fault indicator location map, and the fault location will be pushed to the relevant operation and maintenance personnel. If not, no action will be taken.

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