CN214252555U - Anti-ground fault detection circuit and detection equipment - Google Patents
Anti-ground fault detection circuit and detection equipment Download PDFInfo
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- CN214252555U CN214252555U CN202022933279.2U CN202022933279U CN214252555U CN 214252555 U CN214252555 U CN 214252555U CN 202022933279 U CN202022933279 U CN 202022933279U CN 214252555 U CN214252555 U CN 214252555U
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Abstract
The utility model discloses an anti earth fault detection circuitry and check out test set. Wherein, this anti ground fault detection circuit includes: the power supply, the electric energy meter and the plurality of controllable switching devices are connected with each other to generate a three-phase live wire and a zero line, the plurality of controllable switching devices are respectively connected with the three-phase live wire and the zero line to form a three-phase loop, and each controllable switching device independently controls one-phase loop. The utility model provides an anti earth fault detection circuit among the prior art need control two relays and act together, lead to the technical problem of automatic and manual test not convenient for.
Description
Technical Field
The utility model relates to a fault detection field particularly, relates to an anti ground fault detection circuitry and check out test set.
Background
The three-phase direct access type electric meter requires a test for resisting the ground fault in the full performance detection. The detection is to prevent the occurrence of an event that the electricity meter or the electric appliance is burnt out due to the fact that the voltage of the other two phases of the electric energy meter is greatly increased because the zero line of the electricity meter is mistakenly lapped on a certain live line after the zero line of the electricity meter is broken in practical application.
In a test scheme required by a power grid company, the A/B/C three phases are required to be subjected to primary detection for resisting the ground fault under the condition that the phase voltage is increased to 110%, and the electric meter cannot generate the metering fault after the detection is finished every 4 hours. Fig. 1 is a schematic diagram of a conventional anti-ground fault detection circuit, and as shown in fig. 1, before an anti-ground fault test needs to be performed, a relay K4 is switched to disconnect a zero line of an electricity meter. And then according to the detection requirements, three types of ground fault detection, namely, a relay K1 is driven to simulate a zero line to be in false lap joint with an A-phase live wire, a relay K2 is driven to simulate a zero line to be in false lap joint with a B-phase live wire, or a relay K3 is driven to simulate a zero line to be in false lap joint with a C-phase live wire, are respectively carried out.
In the above detection, 4 sets of relays are required, each set of relays must be able to work independently, so that 4 independent control signals are necessary for realizing the function of the anti-ground fault detection circuit. No matter which kind of ground fault test is simulated, two relays must be driven to work, one relay is a zero line relay K4, and the other relay is any one of three live wires of A/B/C.
However, there is a relatively high demand for some multi-functional detection devices. In some multi-functional testing devices, multiple testing capabilities are often integrated, and accordingly, multiple driver control ports are also required to serve each testing module. One detection item occupies 4 control ports, and is difficult for some devices with insufficient control ports. And each test also has to control two relays to act together, which is not good for automatic and manual tests.
In view of the above problems, no effective solution has been proposed.
SUMMERY OF THE UTILITY MODEL
An embodiment of the utility model provides an anti ground fault detection circuitry and check out test set to at least, solve the anti ground fault detection circuitry among the prior art and need control two relays and act together, lead to the technical problem of automatic and manual test of being not convenient for.
According to an aspect of the embodiments of the present invention, there is provided an anti-ground fault detection circuit, including: the power supply and the electric energy meter are connected with each other to generate a three-phase live wire and a zero line, the controllable switching devices are respectively connected with the three-phase live wire and the zero line to form a three-phase loop, and each controllable switching device independently controls one-phase loop.
Optionally, the three-phase circuit comprises: a first phase loop, a second phase loop, a third phase loop, the plurality of controllable switching devices comprising: a first controllable switching device for controlling the first phase loop, a second controllable switching device for controlling the second phase loop, and a third controllable switching device for controlling the third phase loop.
Optionally, the controllable switching device comprises at least two sets of switches.
Optionally, a center contact of a first group of switches of the first controllable switch device is connected with the first phase live wire, a normally closed contact is suspended, a normally open contact is connected with the zero line end of the electric energy meter, a center contact of a second group of switches of the first controllable switch device is connected with a center contact of a second group of switches of the second controllable switch device, the normally closed contact is connected with the zero line end of the electric energy meter, and the normally open contact is suspended.
Optionally, a center contact of the first group of switches of the second controllable switch device is connected with the second phase live wire, the normally closed contact is suspended, the normally open contact is connected with the zero line end of the electric energy meter, a center contact of the second group of switches of the second controllable switch device is connected with a center contact of the second group of switches of the first controllable switch device, the normally closed contact is connected with the normally closed contact of the first group of switches of the third controllable switch device, and the normally open contact is suspended.
Optionally, a center contact of a first group of switches of the third controllable switch device is connected with the second phase live wire, a normally closed contact is suspended, a normally open contact is connected with the zero line end of the electric energy meter, a center contact of a second group of switches of the third controllable switch device is connected with the zero line end of the power supply, a normally closed contact is connected with a normally closed contact of a second group of switches of the second controllable switch device, and the normally open contact is suspended.
Optionally, the controllable switching device is a double-pole double-throw relay or a multiple-pole double-throw relay.
Optionally, the voltage of the controllable switching device is greater than 400V.
Optionally, the dielectric strength between the working line package and the switch contact of the controllable switching device is greater than 1000V.
According to the utility model discloses on the other hand, still provide a check out test set, check out test set includes any one of the aforesaid anti ground fault detection circuit.
The embodiment of the utility model provides an in, this anti ground fault detection circuit includes: the power, electric energy meter and a plurality of controllable switch device, the power with connect between the electric energy meter and generate three-phase live wire and a zero line, a plurality of controllable switch device respectively with the three-phase live wire with a zero line is connected, forms the three-phase return circuit, wherein, a phase return circuit of each controllable switch device independent control, through each controllable switch device independent control in this anti earth fault detection circuitry, has reached the simple and convenient purpose of control, thereby realized the technological effect of being convenient for automatic control and manual control, and then solved the anti earth fault detection circuitry among the prior art and need control two relays and act together, lead to the technical problem of being not convenient for automatic and manual test.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without undue limitation to the invention. In the drawings:
FIG. 1 is a schematic diagram of a presently conventional anti-ground fault detection circuit;
fig. 2 is a schematic diagram of an anti-ground fault detection circuit according to an embodiment of the present invention;
fig. 3 is a schematic diagram of an anti-ground fault detection circuit according to an alternative embodiment of the present invention.
Detailed Description
In order to make the technical solution of the present invention better understood, the technical solution of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts shall belong to the protection scope of the present invention.
It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
Example 1
According to the utility model discloses an aspect of the embodiment provides an anti ground fault detection circuit, and fig. 2 is according to the utility model discloses an anti ground fault detection circuit's schematic diagram, as shown in fig. 2, this anti ground fault detection circuit includes: the power supply 20, the electric energy meter 22 and the plurality of controllable switching devices 24, wherein the power supply 20 and the electric energy meter 22 are connected to generate a three-phase live wire and a zero wire, the plurality of controllable switching devices 24 are respectively connected with the three-phase live wire and the zero wire to form a three-phase loop, and each controllable switching device 24 independently controls one-phase loop.
The embodiment of the utility model provides an in, this anti ground fault detection circuitry includes power 20 at least, electric energy meter 22 and a plurality of controllable switch device 24, connect between power 20 and the electric energy meter 22 and generate three-phase live wire and a zero line, a plurality of controllable switch device 24 are connected with three-phase live wire and a zero line respectively, form the three-phase return circuit, wherein, a looks return circuit of each controllable switch device 24 independent control, through a looks return circuit of each controllable switch device independent control in this anti ground fault detection circuitry, the simple and convenient purpose of control has been reached, thereby realized being convenient for automatic control and manual control's technological effect, and then solved anti ground fault detection circuitry among the prior art and need controlled two relays and act together, lead to the technical problem who is not convenient for automatic and manual test.
Optionally, the three-phase circuit comprises: a first phase circuit, a second phase circuit, a third phase circuit, the plurality of controllable switching devices comprising: the controllable switching device comprises a first controllable switching device, a second controllable switching device and a third controllable switching device, wherein the first controllable switching device is used for controlling the first phase loop, the second controllable switching device is used for controlling the second phase loop, and the third controllable switching device is used for controlling the third phase loop.
In a specific implementation process, the plurality of controllable switching devices are three controllable switching devices, and the three controllable switching devices are used for respectively controlling the corresponding loops, namely, the three controllable switching devices are controlled by 3 paths of independent driving signals. And each phase impedance ground fault detection only needs to control the controllable switch device of the corresponding phase, so that the control is simple and convenient.
Optionally, the controllable switching device 24 comprises at least two sets of switches.
Optionally, the center contact of the first group of switches of the first controllable switching device is connected to the first phase live wire, the normally closed contact is suspended, the normally open contact is connected to the null line end of the electric energy meter 22, the center contact of the second group of switches of the first controllable switching device is connected to the center contact of the second group of switches of the second controllable switching device, the normally closed contact is connected to the null line end of the electric energy meter 22, and the normally open contact is suspended.
Optionally, the center contact of the first group of switches of the second controllable switching device is connected to the second phase live wire, the normally closed contact is suspended, the normally open contact is connected to the zero line end of the electric energy meter 22, the center contact of the second group of switches of the second controllable switching device is connected to the center contact of the second group of switches of the first controllable switching device, the normally closed contact is connected to the normally closed contact of the first group of switches of the third controllable switching device, and the normally open contact is suspended.
Optionally, the center contact of the first group of switches of the third controllable switching device is connected to the second phase live wire, the normally closed contact is suspended, the normally open contact is connected to the null line end of the electric energy meter 22, the center contact of the second group of switches of the third controllable switching device is connected to the null line end of the power supply 20, the normally closed contact is connected to the normally closed contact of the second group of switches of the second controllable switching device, and the normally open contact is suspended.
Optionally, the controllable switching device 24 is a double-pole double-throw relay or a multiple-pole double-throw relay.
In an implementation, the controllable switching device 24 includes, but is not limited to, a double-pole double-throw relay or a multi-pole double-throw relay, and may be other controllable switching devices having similar switching functions.
Optionally, the voltage of the controllable switching device 24 is greater than 400V.
Optionally, the dielectric strength between the working line package and the switch contact of the controllable switching device 24 is greater than 1000V.
In the specific implementation process, the voltage of the controllable switching device 24 is greater than 400V, and the insulation withstand voltage between the working wire package of the controllable switching device 24 and the switch contact is greater than 1000V, so that the safety of the control signal can be effectively ensured.
An alternative embodiment of the invention is described below.
Fig. 3 is a schematic diagram of an anti-ground fault detection circuit according to an alternative embodiment of the present invention, as shown in fig. 3, K1/K2/K3 in the dashed box represents 3 double-pole double-throw relays, LA/LB/LC/LN represents 3-phase live wire and 1-zero-wire signal terminal of three-phase four-wire of the power supply side, and UA/UB/UC/UN represents 3-phase live wire and 1-zero-wire signal terminal of three-phase four-wire of the power meter side, respectively. K1/K2/K3 are respectively connected with three live wires, and each relay is distributed with an independent control signal.
Optionally, a double pole double throw relay K1 is connected to the phase a loop. And the center contact of the group of switches is connected with the A-phase live wire on the power supply side, the normally closed contact is not suspended, and the normally open contact is connected with the zero line end of the three-phase meter. And the center contact of the other group of switches is connected with the center contact of a certain group of the successive electrical appliance K2B, the normally closed contact is connected with the zero line end of the three-phase meter, and the normally open contact is suspended. The two sets of switches are not in sequence.
Optionally, a double pole double throw relay K2 is connected to the B phase loop. And the center contact of the group of switches is connected with a B-phase live wire on the power supply side, the normally closed contact is not suspended, and the normally open contact is connected with the zero line end of the three-phase meter. And the center contact of the other group of switches is connected with the center contact connected to the successive electrical appliance K1A, the normally closed contact is connected with the normally closed contact of the successive electrical appliance K3C, and the normally open contact is suspended. The two sets of switches are not in sequence.
Optionally, a double pole double throw relay K3 is connected to the C-phase loop. And the center contact of the group of switches is connected with a C-phase live wire on the power supply side, the normally closed contact is not suspended, and the normally open contact is connected with the zero line end of the three-phase meter. And the center contact of the other group of switches is connected with a zero line on the power supply side, the normally closed contact is connected with the group of normally closed contacts connected from the B successive electric appliance K2, and the normally open contact is suspended. The two sets of switches are not in sequence.
In the three relays, each relay can be independently controlled, and the specific implementation process is as follows:
as an optional embodiment, when the condition that a zero line on one side of an analog electric meter is disconnected and a phase A live line is in false lap joint is required, a relay K1 is independently driven to act, a contact of the relay is switched to a normally open contact from a normally closed contact, UN originally connected with LN through K1, K2 and K3 is disconnected at K1 and connected to LA, the UN and UA are in short circuit, at the moment, the voltage of UA to the zero line is 0, but the voltage of UB and UC to the zero line is changed into the line voltage. The test meets the requirement of the simulation environment of false lap joint of the A-phase live wire when the zero line is broken. After the test is finished, the drive control signal of the relay K1 is cancelled, and the circuit is recovered to a normal working state.
As an alternative embodiment, when the zero line on one side of the analog electric meter is required to be disconnected and the B-phase live line is in false lap joint, the relay K2 is independently driven to act, and the contact of the relay K2 is switched from a normally closed contact to a normally open contact. The UN signal, which was originally connected to LN via K1, K2 and K3, is disconnected at K2, while LB is connected to UN, shorting UN to UB. At this time, the UB to zero line voltage is 0, but UA and UC to zero line voltage become line voltages. The test meets the requirement of the simulation environment of the false lapping of the zero line and the B-phase live wire. After the test is finished, the drive control signal of the relay K2 is cancelled, so that the circuit is restored to the normal working state.
As an alternative embodiment, when the condition that the zero line on one side of the electric meter is disconnected and the C-phase live line is in false lap joint is required, the relay K3 is independently driven to act, and the contact of the relay K3 is switched from a normally closed contact to a normally open contact. The UN signal, originally connected to LN via K1, K2 and K3, is disconnected at K3 and LC is connected to UN to short UN to UC, which is 0 to zero line voltage, but UA and UB to zero line voltage becomes the line voltage. The test meets the requirement of the simulation environment of the false lapping of the zero line and the C-phase live wire. After the test is finished, the drive control signal of the relay K3 is cancelled, so that the circuit is restored to the normal working state.
Through the anti-ground fault detection circuit in the embodiment, 3 double-pole double-throw relays can be adopted, and all anti-ground fault test requirements required in the technical specification of a power grid can be simply met through 3 paths of independent driving control signals. Moreover, only one relay needs to be driven for each phase of test, so that automatic control and manual control are facilitated.
Example 2
According to the utility model discloses on the other hand, still provide a check out test set, this check out test set includes the anti ground fault detection circuitry of any one of the above-mentioned.
The above embodiment numbers of the present invention are only for description, and do not represent the advantages and disadvantages of the embodiments.
In the above embodiments of the present invention, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to the related descriptions of other embodiments.
In the embodiments provided in the present application, it should be understood that the disclosed technology can be implemented in other ways. The above-described embodiments of the apparatus are merely illustrative, and for example, the division of the units may be a logical division, and in actual implementation, there may be another division, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, units or modules, and may be in an electrical or other form.
The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.
In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.
The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to perform all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a removable hard disk, a magnetic or optical disk, and other various media capable of storing program codes.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (10)
1. An anti-ground fault detection circuit, comprising: the power supply and the electric energy meter are connected with each other to generate a three-phase live wire and a zero line, the controllable switching devices are respectively connected with the three-phase live wire and the zero line to form a three-phase loop, and each controllable switching device independently controls one-phase loop.
2. The circuit of claim 1, wherein the three-phase loop comprises: a first phase loop, a second phase loop, a third phase loop, the plurality of controllable switching devices comprising: a first controllable switching device for controlling the first phase loop, a second controllable switching device for controlling the second phase loop, and a third controllable switching device for controlling the third phase loop.
3. A circuit according to claim 2, characterized in that the controllable switching device comprises at least two groups of switches.
4. The circuit of claim 3, wherein the center contact of the first set of switches of the first controllable switching device is connected to the first phase live wire, the normally closed contact is floating, the normally open contact is connected to the neutral wire end of the electric energy meter, the center contact of the second set of switches of the first controllable switching device is connected to the center contact of the second set of switches of the second controllable switching device, the normally closed contact is connected to the neutral wire end of the electric energy meter, and the normally open contact is floating.
5. The circuit of claim 4, wherein the center contact of the first set of switches of the second controllable switching device is connected to the second phase live line, the normally closed contact is floating, the normally open contact is connected to the neutral line terminal of the electric energy meter, the center contact of the second set of switches of the second controllable switching device is connected to the center contact of the second set of switches of the first controllable switching device, the normally closed contact is connected to the normally closed contact of the first set of switches of the third controllable switching device, and the normally open contact is floating.
6. The circuit of claim 5, wherein the center contact of the first set of switches of the third controllable switching device is connected to the second phase power line, the normally closed contact is floating, the normally open contact is connected to the neutral line terminal of the electric energy meter, the center contact of the second set of switches of the third controllable switching device is connected to the neutral line terminal of the power supply, the normally closed contact is connected to the normally closed contact of the second set of switches of the second controllable switching device, and the normally open contact is floating.
7. A circuit according to any one of claims 1 to 6, characterized in that the controllable switching device is a double pole double throw relay or a multiple pole double throw relay.
8. A circuit as claimed in any one of claims 1 to 6, characterized in that the voltage of the controllable switching device is greater than 400V.
9. A circuit according to any one of claims 1 to 6, characterized in that the withstand voltage between the working package of the controllable switching device and the switching contact is greater than 1000V.
10. A detection device, characterized in that it comprises an anti-ground fault detection circuit according to any one of claims 1 to 9.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202022933279.2U CN214252555U (en) | 2020-12-09 | 2020-12-09 | Anti-ground fault detection circuit and detection equipment |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202022933279.2U CN214252555U (en) | 2020-12-09 | 2020-12-09 | Anti-ground fault detection circuit and detection equipment |
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| CN214252555U true CN214252555U (en) | 2021-09-21 |
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| CN202022933279.2U Active CN214252555U (en) | 2020-12-09 | 2020-12-09 | Anti-ground fault detection circuit and detection equipment |
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