Electric leakage monitoring device and method with remote self-checking function

Abstract

The invention discloses an electric leakage monitoring device and method with a remote self-checking function. The device comprises a main control processor, a control bus, a monitoring platform and branch equipment, the main control processor is respectively connected with the control bus and the monitoring platform; the branch equipment is arranged corresponding to the branch and comprises a power-off control unit and an electric leakage mutual inductor; the power-off control unit comprises a first-order relay and a second-order relay; the electric leakage mutual inductor comprises a magnetic ring, a detection coil and a self-checking coil are wound on the magnetic ring, and the detection coil and the self-checking coil are not in contact. By arranging the electric leakage mutual inductor, whether branch electric leakage exists or not can be monitored in real time, and electric leakage mutual inductor self-inspection can be performed through the detection coil and the self-inspection coil, so that the precision of a monitoring result is ensured. The first-order relay and the second-order relay can control the alternating current contactor to be connected or disconnected, so that the first-order relay and the second-order relay can be self-detected respectively, and the electric leakage branch can be reliably cut off when the electric leakage branch is detected.

Description

Technical Field

[0001] The present invention relates to the technical field of street lamp monitoring, and more specifically, to a leakage monitoring device and method with a remote self-checking function. Background Art

[0002] Urban street lighting is increasingly related to people's production and life. At present, street lighting projects in some cities have installed street light leakage monitoring equipment to avoid or reduce the harm of street light leakage to pedestrians.

[0003] However, the existing street lamp leakage detection equipment has the following problems: 1. It is impossible to confirm whether the external leakage transformer of each branch is installed intact and working properly. In practical applications, it is necessary to install an external leakage monitoring transformer on each branch A, B, C, N three-phase four-wire cable or single-phase live and neutral cable of the distribution box. However, due to the large number of cable branches in the street lamp box, it is easy to miss the installation. In the case of missing transformers, the leakage current collected by the monitoring terminal is 0. When the transformer is installed and there is no leakage in the single-phase or three-phase four-wire cable, the leakage current is also 0. Therefore, it is impossible to remotely confirm whether the external transformer is installed and working properly from the monitoring platform system, which brings a huge risk of missing reports to the leakage monitoring of street lamps, thereby causing serious safety hazards. 2. The situation of failure of the metering and collection circuit of the leakage monitoring equipment is not considered. After the leakage monitoring terminal is installed and debugged, after a long period of operation, the failure of other electrical appliances or improper human operation may cause the failure of the leakage monitoring terminal equipment. At the same time, we cannot find that the monitoring equipment has failed, which brings various new problems. This requires that street lamp maintenance personnel need to go to the site to test the working condition of the leakage monitoring device collection function in a timely manner, which increases the cost and complexity of on-site maintenance. 3. Unable to control power outages. When the street lamp is powered on normally, if leakage is detected in the street lamp box, the monitoring device needs to disconnect the power supply output of the subsequent stage as soon as possible and cut off the leakage line to ensure that there is no personal danger. At present, the leakage monitoring devices of street lamps do not have the function of self-test control.

[0004] To sum up, the street light leakage monitoring device needs to be able to accurately self-check whether the leakage transformer is installed in place and whether it is working properly. At the same time, the metering and collection part of the device also needs to operate stably and be able to cut off the power output stably and quickly when leakage occurs.

[0005] Therefore, the present invention provides a leakage monitoring device and method with a remote self-checking function. Summary of the invention

[0006] In view of this, the present invention provides a leakage monitoring device and method with a remote self-checking function.

[0007] On the one hand, the present invention provides a leakage monitoring device with a remote self-checking function, which is arranged in a street light box transformer, wherein the street light box transformer includes a total neutral line and a total phase line, and also includes at least one branch, wherein the branch includes an AC contactor, an identification phase line, an identification neutral line and a load, wherein the input end of the identification phase line is connected to the total phase line via the AC contactor, the output end of the identification phase line is connected to the positive pole of the load, the input end of the identification neutral line is connected to the total neutral line via the AC contactor, and the output end of the identification neutral line is connected to the negative pole of the load, and includes: a main control processor, a control bus, a monitoring platform and branch equipment;

[0008] The main control processor is connected to the control bus and the monitoring platform respectively;

[0009] The branch circuit equipment is arranged corresponding to the branch circuit, including a power-off control unit and a leakage transformer:

[0010] The power-off control unit comprises a first-order relay and a second-order relay, wherein both the first-order relay and the second-order relay are single-pole double-throw relays; the first-order relay comprises a first-order relay common end, a first-order relay normally open end, a first-order relay normally closed end and a first-order relay control end, wherein the first-order relay common end is connected to the total phase line, the first-order relay normally open end is connected to the control end of the AC contactor, and the first-order relay control end is connected to the control bus; the second-order relay comprises a second-order relay common end, a second-order relay normally open end, a second-order relay normally closed end and a second-order relay control end, wherein the second-order relay common end is connected to the total phase line, the second-order relay normally open end is connected to the control end of the AC contactor, and the second-order relay control end is connected to the control bus; the first-order relay normally open end, the first-order relay normally closed end, the second-order relay normally open end and the second-order relay normally closed end are all connected to a voltage detector, wherein the output end of the voltage detector is connected to the input end of a sampling unit, and the output end of the sampling unit is connected to the control bus;

[0011] The leakage current transformer comprises a magnetic ring, which is sleeved outside the identification neutral line and the identification phase line, and is wound with a detection coil and a self-detection coil, the detection coil and the self-detection coil are non-contact, and the detection coil is connected to the input end of the sampling unit; the self-detection coil comprises at least three interfaces, the number of coil turns between any two adjacent interfaces is an integer, all the interfaces are connected to an interface switching switch, the control end of the interface switching switch is connected to the control bus, and the input end of the interface switching switch is connected to the output end of the standard constant current source unit.

[0012] Optionally, the interface switching switch includes a primary switch and a secondary switch connected in sequence, the primary switch is connected to the output end of the standard constant current source unit, and the secondary switch is connected to the interface;

[0013] The primary switch is used to adjust the current output by the standard constant current source unit, and the secondary switch is used to turn on or off the interface.

[0014] Optionally, the number of the total phase lines is 3;

[0015] In any of the power-off control units, the common end of the first-order relay is connected to any one of the total phase lines; the total phase line to which the common end of the second-order relay is connected is the same as the total phase line to which the common end of the first-order relay is connected.

[0016] On the other hand, the present invention provides a leakage monitoring method with a remote self-checking function, which is applied to any of the leakage monitoring devices with a remote self-checking function described above, and includes: a self-checking process and a leakage monitoring process;

[0017] The self-test process includes the self-test of the power-off control unit, and the self-test of the power-off control unit includes:

[0018] The main control processor controls the first-order relay to turn on the normally open end of the first-order relay, and the second-order relay to turn on the normally closed end of the second-order relay; the main control processor obtains the first-order relay normally open end voltage fed back by the voltage detector connected to the normally open end of the first-order relay and the second-order relay normally closed end voltage fed back by the voltage detector connected to the normally closed end of the second-order relay; the main control processor controls the first-order relay to turn on the normally closed end of the first-order relay, and the second-order relay to turn on the normally open end of the second-order relay; the main control processor obtains the voltage detector connected to the normally closed end of the first-order relay The first-order relay normally closed end voltage fed back by the voltage detector and the second-order relay normally open end voltage fed back by the voltage detector connected to the second-order relay normally open end; the main control processor determines whether the first-order relay normally open end voltage and the second-order relay normally open end voltage are preset voltages, and whether the first-order relay normally closed end voltage and the second-order relay normally closed end voltage are 0; if the first-order relay normally open end voltage and the second-order relay normally open end voltage are the preset voltages and the first-order relay normally closed end voltage and the second-order relay normally closed end voltage are 0, the main control processor determines that the power-off control unit is working normally;

[0019] The leakage monitoring process includes: the main control processor obtains the leakage current transmitted by the sampling unit, and transmits the leakage current to the monitoring platform for display.

[0020] Optionally, after the main control processor acquires the leakage current transmitted by the sampling unit, the method further includes:

[0021] The main control processor determines whether the leakage current is not zero. If the leakage current is not zero, the main control processor determines the corresponding branch according to the leakage current that is not zero, and controls the normally closed end of the first-order relay and the normally closed end of the second-order relay corresponding to the determined branch to be turned on at the same time.

[0022] Optionally, the self-test process further includes self-testing the leakage current transformer and the sampling unit, and the self-testing of the leakage current transformer and the sampling unit includes:

[0023] The main control processor controls the interface switching switch to connect the two interfaces;

[0024] The main control processor obtains the detection current transmitted by the sampling unit, calculates the theoretical current according to the current output by the standard constant current source unit, the number of coil turns between the two interfaces that are turned on, and the transformation ratio of the leakage transformer, and determines whether the detection current is equal to the theoretical current. If the detection current is equal to the theoretical current, the main control processor determines that the leakage transformer and the sampling unit are operating normally.

[0025] Compared with the prior art, the leakage monitoring device and method with remote self-checking function provided by the present invention achieves at least the following beneficial effects:

[0026] 1. The leakage monitoring device and method with remote self-checking function provided by the present invention, when the first-order relay conducts the normally open end of the first-order relay, the second-order relay is disconnected, and the normally open end voltage of the first-order relay and the normally closed end voltage of the second-order relay can be measured; when the second-order relay conducts the normally open end of the second-order relay, the first-order relay is disconnected, and the normally closed end voltage of the first-order relay and the normally open end voltage of the second-order relay can be obtained. According to the normally open end voltage of the first-order relay, the normally closed end voltage of the first-order relay, the normally open end voltage of the second-order relay and the normally closed end voltage of the second-order relay, it is verified whether the power-off control unit works normally according to the instructions of the main control processor and does not affect the normal operation of the branch. The control end of the first-order relay and the control end of the second-order relay are connected to the main control processor via a control bus. When leakage occurs in the branch, the main control processor can control the first-order relay and the second-order relay to be disconnected at the same time to disconnect the AC contactor, thereby cutting off the branch, and then preventing the branch from causing damage due to leakage.

[0027] 2. The leakage monitoring device and method with remote self-checking function provided by the present invention, when there is no leakage in the branch, the currents of the marking neutral line and the marking phase line are equal and in opposite directions, and the leakage current output by the sampling unit is 0. If the leakage current output by the sampling unit is not 0, it can be detected that there is leakage in the branch, thereby realizing real-time monitoring of whether the branch is leaking.

[0028] 3. The leakage monitoring device and method with remote self-test function provided by the present invention provide rated current to the self-test coil through a standard constant current source unit, calculate the theoretical current according to the rated current, the number of coil turns connected to the self-test coil and the transformation ratio of the leakage transformer, and judge whether the detection current output by the sampling unit is equal to the theoretical current, thereby judging whether the leakage transformer is working normally, and further checking whether the accuracy and linearity of the leakage transformer and the sampling unit meet the requirements.

[0029] Of course, any product implementing the present invention does not necessarily need to achieve all of the technical effects described above at the same time.

[0030] Further features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0032] Figure 1 It is a partial structural schematic diagram of the leakage monitoring device with remote self-checking function provided by the present invention.

[0033] Figure 2 It is a partial structural schematic diagram of the leakage monitoring device with remote self-checking function provided by the present invention.

[0034] Figure 3 It is a topological diagram of the switching mechanism of the self-test standard source output of the leakage transformer.

[0035] In the figure: 1. total neutral line; 2. total phase line; 3. phase line identification; 4. neutral line identification; 5. load; 6. main control processor; 7. control bus; 8. monitoring platform; 9. power-off control unit; 10. first-order relay; 11. second-order relay; 12. leakage transformer; 13. magnetic ring; 14. detection coil; 15. self-test coil; 16. sampling unit; 17. interface; 18. interface switching switch; 19. standard constant current source unit; 20. AC contactor. DETAILED DESCRIPTION

[0036] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0037] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0038] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0039] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0040] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0041] Example 1

[0042] Combination Figure 1 and Figure 2 , Figure 1 It is a partial structural diagram of the leakage monitoring device with remote self-checking function provided by the present invention. Figure 2 It is a partial structural schematic diagram of the leakage monitoring device with remote self-checking function provided by the present invention, and is used to illustrate a specific embodiment of the leakage monitoring device with remote self-checking function provided by the present invention.

[0043] The leakage monitoring device with remote self-checking function provided in the present embodiment is arranged in a street light box-type transformer, the street light box-type transformer includes a total neutral line 1 and a total phase line 2, and also includes at least one branch, the branch includes an AC contactor 20, an identification phase line 3, an identification neutral line 4 and a load 5, the input end of the identification phase line 3 is connected to the total phase line 2 via the AC contactor 20, the output end of the identification phase line 3 is connected to the positive pole of the load 5, the input end of the identification neutral line 4 is connected to the total neutral line 1 via the AC contactor 20, and the output end of the identification neutral line 4 is connected to the negative pole of the load 5, including: a main control processor 6, a control bus 7, a monitoring platform 8 and branch equipment;

[0044] The main control processor 6 is connected to the control bus 7 and the monitoring platform 8 respectively;

[0045] Branch equipment and branch corresponding settings, including:

[0046] A power-off control unit 9 includes a first-order relay 10 and a second-order relay 11, both of which are single-pole double-throw relays; the first-order relay 10 includes a first-order relay common end, a first-order relay normally open end, a first-order relay normally closed end and a first-order relay control end, the first-order relay common end is connected to the total phase line 2, the first-order relay normally open end is connected to the control end of the AC contactor 20, and the first-order relay control end is connected to the control bus 7; the second-order relay 11 includes a second-order relay common end, a second-order relay normally open end, a second-order relay normally closed end and a second-order relay control end, the second-order relay common end is connected to the total phase line 2, the second-order relay normally open end is connected to the control end of the AC contactor 20, and the second-order relay control end is connected to the control bus 7; the first-order relay normally open end, the first-order relay normally closed end, the second-order relay normally open end and the second-order relay normally closed end are all connected to a voltage detector, the output end of the voltage detector is connected to the input end of the sampling unit 16, and the output end of the sampling unit 16 is connected to the control bus 7;

[0047] The leakage mutual inductor 12 includes a magnetic ring 13, which is sleeved outside the marking neutral line 4 and the marking phase line 3. The magnetic ring 13 is wound with a detection coil 14 and a self-detection coil 15. The detection coil 14 and the self-detection coil 15 are non-contact, and the detection coil 14 is connected to the input end of the sampling unit 16; the self-detection coil 15 includes at least three interfaces 17, and the number of coil turns between any two adjacent interfaces 17 is an integer. All interfaces 17 are connected to an interface switching switch 18, and the control end of the interface switching switch 18 is connected to the control bus 7, and the input end of the interface switching switch 18 is connected to the output end of the standard constant current source unit 19.

[0048] It should be noted that the monitoring platform 8 is wirelessly connected to the main control processor 6. Specifically, the branch device may also include a wireless communication unit. The monitoring platform 8 is wirelessly connected to the main control processor 6 through the wireless communication unit to achieve remote leakage monitoring. The wireless communication unit can use an LTE Cat.1 wireless communication unit, of course, not limited to this. The main control processor 6 controls the operation of the branch device and controls the work of each unit through rigorous logical coordination. The main control processor 6 can be a single-chip microcomputer. Of course, it is not limited to this. The client or the monitoring platform 8 can remotely transmit the patrol control instruction to the main control processor 6 through the wireless communication unit to perform self-test of the power-off control unit 9, the leakage transformer 12 and the sampling unit 16. The standard constant current source unit 19 adopts the existing standard constant current source circuit, the standard constant current source unit 19 is connected to the external power supply for independent power supply, and the sampling unit 16 can use the existing sampling circuit. It can also be provided with an AC input rectifier filter unit to filter the current input to the standard constant current source unit 19. Of course, it is not limited to this. In this embodiment, the load 5 is a street lamp, of course, it can also be adjusted according to actual needs.

[0049] It can be understood that the leakage monitoring device with remote self-checking function provided in this embodiment can perform self-checking of the power-off control unit 9, the main control processor 6 controls the first-order relay 10 to conduct the first-order relay normally open end, and the second-order relay 11 is disconnected, and the first-order relay normally open end voltage and the second-order relay normally closed end voltage can be measured; the main control processor 6 then controls the second-order relay 11 to conduct the second-order relay normally open end, and the first-order relay 10 is disconnected, and the first-order relay normally closed end voltage and the second-order relay normally open end voltage can be obtained. According to the first-order relay normally open end voltage, the first-order relay normally closed end voltage, the second-order relay normally open end voltage and the second-order relay normally closed end voltage, it is verified whether the power-off control unit 9 works normally according to the instructions of the main control processor 6 and does not affect the normal operation of the branch. The first-order relay control end and the second-order relay control end are connected to the main control processor 6 via the control bus 7. When leakage occurs in the branch, the main control processor 6 can control the first-order relay 10 and the second-order relay 11 to be disconnected at the same time to disconnect the AC contactor 20, thereby cutting off the branch, thereby preventing the branch from causing damage due to leakage.

[0050] The leakage monitoring device with remote self-checking function provided in this embodiment can also perform self-checking of the leakage transformer 12 and the sampling unit 16. The rated current is provided to the self-checking coil 15 through the standard constant current source unit 19. If the detection coil 14 generates current output, the leakage transformer 12 has been installed and works normally. The theoretical current is calculated according to the rated current, the number of coil turns connected to the self-checking coil 15, and the transformation ratio of the leakage transformer 12, and it is determined whether the detection current output by the sampling unit 16 is equal to the theoretical current, so as to further check whether the accuracy and linearity of the leakage transformer 12 and the sampling unit 16 meet the requirements.

[0051] The leakage monitoring device with remote self-test function provided in this embodiment can also monitor the leakage situation in real time. The interfaces 17 are all disconnected. When there is no leakage in the branch, the currents of the identification neutral line 4 and the identification phase line 3 are equal and in opposite directions, so no electromagnetic induction current is generated. Therefore, the detection coil 14 does not generate any current output, and the leakage current output by the sampling unit 16 is 0. If the leakage current output by the sampling unit 16 is not 0, it can be detected that there is leakage in the branch, thereby realizing real-time monitoring of whether the branch is leaking.

[0052] Therefore, the leakage monitoring device with remote self-checking function provided in this embodiment can effectively self-check whether the leakage transformer 12 is installed and working normally, and whether the acquisition accuracy and linearity of the leakage transformer 12 meet the requirements, and timely find out whether the leakage transformer 12 has drifted and changed with the increase of service life or the change of environment, eliminate the influence of the failure of the leakage transformer 12 on the leakage collection, and verify the integrity of the sampling unit 16. In addition, the self-checking function of the power-off control unit 9 can verify whether the power supply output can be reliably disconnected when leakage is detected, thereby protecting the subsequent load 5, reducing danger, and ensuring the low maintenance, accuracy and stable reliability of the leakage monitoring device with remote self-checking function provided in this embodiment during long-term use.

[0053] Example 2

[0054] Combination Figure 1 , Figure 2 and Figure 3 , Figure 3 It is a topological diagram of the switching mechanism of the self-checking standard source output of the leakage transformer, to illustrate another specific embodiment of the leakage monitoring device with remote self-checking function provided by the present invention.

[0055] The leakage monitoring device with remote self-checking function provided in the present embodiment is arranged in a street light box-type transformer, the street light box-type transformer includes a total neutral line 1 and a total phase line 2, and the number of total phase lines 2 is 3; the street light box-type transformer also includes at least one branch, the branch includes an AC contactor 20, an identification phase line 3, an identification neutral line 4 and a load 5, the input end of the identification phase line 3 is connected to the total phase line 2 via the AC contactor 20, the output end of the identification phase line 3 is connected to the positive pole of the load 5, the input end of the identification neutral line 4 is connected to the total neutral line 1 via the AC contactor 20, and the output end of the identification neutral line 4 is connected to the negative pole of the load 5, including: a main control processor 6, a control bus 7, a monitoring platform 8 and branch equipment;

[0056] The main control processor 6 is connected to the control bus 7 and the monitoring platform 8 respectively;

[0057] Branch equipment and branch corresponding settings, including:

[0058] A power-off control unit 9 comprises a first-order relay 10 and a second-order relay 11, both of which are single-pole double-throw relays; the first-order relay 10 comprises a first-order relay common terminal, a first-order relay normally-open terminal, a first-order relay normally-closed terminal and a first-order relay control terminal, the first-order relay common terminal is connected to any total phase line 2, the first-order relay normally-open terminal is connected to the control terminal of the AC contactor 20, and the first-order relay control terminal is connected to a control bus 7; the second-order relay 11 comprises a second-order relay common terminal, a second-order relay normally-open terminal, a second-order relay normally-closed terminal and a second-order relay control terminal, the total phase line 2 connected to the second-order relay common terminal is the same as the total phase line 2 connected to the first-order relay common terminal, the second-order relay normally-open terminal is connected to the control terminal of the AC contactor 20, and the second-order relay control terminal is connected to the control bus 7; the first-order relay normally-open terminal, the first-order relay normally-closed terminal, the second-order relay normally-open terminal and the second-order relay normally-closed terminal are all connected to a voltage detector, the output terminal of the voltage detector is connected to the input terminal of a sampling unit 16, and the output terminal of the sampling unit 16 is connected to the control bus 7;

[0059] The leakage mutual inductor 12 includes a magnetic ring 13, which is sleeved outside the marking neutral line 4 and the marking phase line 3. The magnetic ring 13 is wound with a detection coil 14 and a self-detection coil 15. The detection coil 14 and the self-detection coil 15 are non-contact, and the detection coil 14 is connected to the input end of the sampling unit 16; the self-detection coil 15 includes at least three interfaces 17, and the number of coil turns between any two adjacent interfaces 17 is an integer. All interfaces 17 are connected to an interface switching switch 18, and the control end of the interface switching switch 18 is connected to the control bus 7, and the input end of the interface switching switch 18 is connected to the output end of the standard constant current source unit 19.

[0060] The interface switching switch 18 includes a primary switch and a secondary switch connected in sequence, the primary switch is connected to the output end of the standard constant current source unit 19, and the secondary switch is connected to the interface 17; the primary switch is used to adjust the current output by the standard constant current source unit, and the secondary switch is used to turn on or off the interface. Figure 2 It is only shown that the number of total phase lines 2 is 1, and the single-phase live wire and neutral wire pass through the leakage transformer 12. Of course, it is not limited to this. The wires drawn from the power grid are usually three-phase four-wire, that is, the number of total phase lines 2 is 3, so the three-phase four-wire can also pass through the leakage transformer 12. Figure 2 The self-test coil 15 is shown as having four interfaces 17. Of course, the positions and numbers of the interfaces 17 can be adjusted according to actual needs, and this embodiment does not impose any specific restrictions on this. The interface switching switch 18 can adopt the existing technology, and this embodiment will not make too many redundant descriptions on this.

[0061] It is understood that the coil between the two interfaces 17 can be used as a winding, for example, Figure 2The four interfaces 17 are interface ①, interface ②, interface ③ and interface ④ respectively. The interface switching switch 18 turns on interface ① and interface ②, that is, connects windings ①②. The interface switching switch 18 turns on interface ① and interface ③, that is, connects windings ①③. The interface switching switch 18 turns on interface ① and interface ④, that is, connects windings ①④. The number of windings of each leakage transformer 12 can be set according to actual needs, and the number of turns of the winding can also be set according to actual needs. For example, the number of turns of the winding can be 5 turns, 10 turns, 15 turns, etc. The main control processor 6 transmits current to the winding through the standard constant current source unit 19. After the current passes through the winding, it can be tested whether the current induced by the detection coil 14 of the leakage transformer 12 is correct. For example, when the standard constant current source unit 19 outputs a current of 100mA, the main control processor 6 outputs the current of 100mA to the windings ①② through the interface switching switch 18. If the number of turns of the windings ①② is 5, and the transformation ratio of the leakage transformer 12 is 1000:1, then the detection coil 14 of the leakage transformer 12 will theoretically sense a current of 0.5mA, so the theoretical leakage current collected by the sampling unit 16 is 500mA. Therefore, whether the leakage transformer 12 is installed and working properly can be verified based on whether the actual leakage current value collected is 500mA. Similarly, the 100mA current output by the standard constant current source unit 19 can be passed through windings ①③ and ①④ respectively. If the number of turns of windings ①③ is 10, the number of turns of windings ①④ is 15, and the transformation ratio of the leakage transformer 12 is still 1000:1, then the detection coil 14 of the leakage transformer 12 will theoretically sense currents of 1mA and 1.5mA respectively, and the theoretical leakage currents collected by the sampling unit 16 are 1000mA and 1500mA respectively. Each time a winding with different turns is turned on, the theoretical leakage current is compared with the actual leakage current collected. Through three current collections, it can be identified whether the collection accuracy and linearity of the leakage transformer 12 meet the requirements.

[0062] Reference Figure 3Since the number of leakage transformers 12 can be multiple, each leakage transformer 12 can be self-checked separately. Each leakage transformer 12 can be provided with one or more windings, and the present embodiment does not impose any specific restrictions on this. When the windings of the leakage transformer 12 are relatively few, the current output by the standard constant current source unit 19 can be adjusted by a primary switch, thereby changing the magnitude of the current value transmitted to the same winding, so that one winding can pass different currents and the acquisition accuracy and linearity of the leakage transformer 12 can also be self-checked. When the windings of the leakage transformer 12 are more, a constant current source with a specific value can be used to switch and connect different windings, and the accuracy and linearity and other parameters of the leakage transformer 12 can also be self-checked and verified. Standard constant current sources with different values, leakage transformers 12 of different branches, and different windings of each leakage transformer 12 can all be controlled by the main control processor 6. For example, a certain relay is controlled to be turned on and off to select and output a certain standard source, and then a certain relay is controlled to select and output to a leakage transformer 12 of a certain branch, and finally a certain relay is used to select and output to a certain winding of the selected leakage transformer 12. In this way, a variety of self-test combination schemes can be formed, and a combination scheme can be selected according to the actual application situation. Each combination scheme can meet the requirements of verifying the working state of the leakage transformer 12 and the accuracy and linearity. At the same time, through this series of self-test operations of the leakage transformer 12, it is also verified whether the sampling is working normally and whether the accuracy and precision of the collection meet the requirements.

[0063] The self-check of the power-off control unit 9 adopts two-stage relay output control and superimposes the voltage acquisition linkage feedback technology. For example, the AC contactor 20 is generally controlled by 220V, one end of the control side is connected to the neutral line, and the other end is connected to any total phase line 2. The control output of the total phase line 2 is controlled by two-stage relays to realize self-checking. The relay of each branch output control adopts a single-pole double-throw relay of the default normally open type. The total phase line 2 is connected to the common end of the relay, and the common end is connected to the normally closed end by default, and the normally open end is connected to the AC contactor 20. When it is necessary to control the AC contactor 20 to be closed, the main control processor 6 controls the relay to be dialed to the normally open end, and the total phase line 2 output can control the AC contactor 20 to be closed. When it is necessary to control the AC contactor 20 to be disconnected, the main control processor 6 controls the relay to be dialed to the normally closed end, and the total phase line 2 does not output to control the AC contactor 20 to be disconnected. When the common end of the relay is dialed to the normally open end, the voltage of the normally open end can be detected to verify whether the relay operates normally according to the instruction of the main control processor 6. Similarly, when the common terminal of the relay is dialed to the normally closed terminal, the voltage of the normally closed terminal can be detected to verify whether the relay has been operating normally. Each order of control supports the control of multiple branches, and the normally open terminal and the normally closed terminal of the relay support voltage acquisition to verify whether the common terminal contact of the relay is correctly operated to the normally open terminal or the normally closed terminal. When the first-order relay 10 is in the main role of output control, the main control processor 6 can control and coordinate the second-order relay 11 to perform control self-test. When the second-order relay 11 is in the main role of output control, the main control processor 6 can control and coordinate the first-order relay 10 to perform control self-test. In this way, the self-test of the control function can be completed without affecting the normal output control.

[0064] Example 3

[0065] Based on the same invention idea, continue to refer to Figure 1 and Figure 2 The present invention also provides a leakage monitoring method with a remote self-checking function, which is applied to the leakage monitoring device with a remote self-checking function described in any one of the above embodiments, including: a self-checking process and a leakage monitoring process;

[0066] The self-check process includes the self-check of the power-off control unit 9, and the self-check of the power-off control unit 9 includes:

[0067] The main control processor 6 controls the first-order relay 10 to turn on the normally open end of the first-order relay, and the second-order relay 11 to turn on the normally closed end of the second-order relay; the main control processor 6 obtains the normally open end voltage of the first-order relay fed back by the voltage detector connected to the normally open end of the first-order relay and the normally closed end voltage of the second-order relay fed back by the voltage detector connected to the normally closed end of the second-order relay; the main control processor 6 controls the first-order relay 10 to turn on the normally closed end of the first-order relay, and the second-order relay 11 to turn on the normally open end of the second-order relay; the main control processor 6 obtains the voltage detection connected to the normally closed end of the first-order relay The main control processor 6 determines whether the first-order relay normally open end voltage and the second-order relay normally open end voltage are preset voltages, and whether the first-order relay normally closed end voltage and the second-order relay normally closed end voltage are 0; if the first-order relay normally open end voltage and the second-order relay normally open end voltage are preset voltages and the first-order relay normally closed end voltage and the second-order relay normally closed end voltage are 0, the main control processor 6 determines that the power-off control unit 9 works normally;

[0068] The self-test process also includes the self-test of the leakage current transformer 12 and the sampling unit 16. The self-test of the leakage current transformer 12 and the sampling unit 16 includes:

[0069] The main control processor 6 controls the interface switching switch 18 to turn on the two interfaces 17; the main control processor 6 obtains the detection current transmitted by the sampling unit 16, calculates the theoretical current according to the current output by the standard constant current source unit 19, the number of coil turns between the two turned-on interfaces 17 and the transformation ratio of the leakage transformer 12, and determines whether the detection current is equal to the theoretical current. If the detection current is equal to the theoretical current, the main control processor 6 determines that the leakage transformer 12 and the sampling unit 16 are working normally.

[0070] The leakage monitoring process includes: the main control processor 6 obtains the leakage current transmitted by the sampling unit 16, and transmits the leakage current to the monitoring platform 8 for display. After the main control processor 6 obtains the leakage current transmitted by the sampling unit 16, it also includes:

[0071] The main control processor 6 determines whether there is a leakage current that is not zero. If there is a leakage current that is not zero, the main control processor 6 determines the corresponding branch according to the leakage current that is not zero, and controls the normally closed end of the first-order relay and the normally closed end of the second-order relay corresponding to the determined branch to be turned on at the same time.

[0072] It should be noted that the control end of the AC contactor 20 can also be set to connect to the control bus 7. If there is a leakage current that is not zero, the main control processor 6 determines the corresponding branch based on the leakage current that is not zero, and directly controls the AC contactor 20 of the determined branch to disconnect. Of course, it is not limited to this.

[0073] It is understandable that if any of the normally open voltage of the first-order relay and the normally open voltage of the second-order relay is not the preset voltage, and / or any of the normally closed voltage of the first-order relay and the normally closed voltage of the second-order relay is not 0, the main control processor 6 determines that the power-off control unit 9 is working abnormally and gives a prompt, or the main control processor 6 determines that the power-off control unit 9 is working abnormally and transmits it to other devices, and other devices give prompts. Similarly, if the detected current is not equal to the theoretical current, the main control processor 6 determines that the working accuracy of the leakage transformer 12 and the sampling unit 16 is abnormal and gives a prompt, or the main control processor 6 determines that the working accuracy of the leakage transformer 12 and the sampling unit 16 is abnormal and transmits it to other devices, and other devices give prompts.

[0074] It can be seen from the above embodiments that the leakage monitoring device and method with remote self-checking function provided by the present invention achieve at least the following beneficial effects:

[0075] 1. The leakage monitoring device and method with remote self-checking function provided by the present invention, when the first-order relay conducts the normally open end of the first-order relay, the second-order relay is disconnected, and the normally open end voltage of the first-order relay and the normally closed end voltage of the second-order relay can be measured; when the second-order relay conducts the normally open end of the second-order relay, the first-order relay is disconnected, and the normally closed end voltage of the first-order relay and the normally open end voltage of the second-order relay can be obtained. According to the normally open end voltage of the first-order relay, the normally closed end voltage of the first-order relay, the normally open end voltage of the second-order relay and the normally closed end voltage of the second-order relay, it is verified whether the power-off control unit works normally according to the instructions of the main control processor and does not affect the normal operation of the branch. The control end of the first-order relay and the control end of the second-order relay are connected to the main control processor via a control bus. When leakage occurs in the branch, the main control processor can control the first-order relay and the second-order relay to be disconnected at the same time to disconnect the AC contactor, thereby cutting off the branch, and then preventing the branch from causing damage due to leakage.

[0076] 2. The leakage monitoring device and method with remote self-checking function provided by the present invention, when there is no leakage in the branch, the currents of the marking neutral line and the marking phase line are equal and in opposite directions, and the leakage current output by the sampling unit is 0. If the leakage current output by the sampling unit is not 0, it can be detected that there is leakage in the branch, thereby realizing real-time monitoring of whether the branch is leaking.

[0077] 3. The leakage monitoring device and method with remote self-test function provided by the present invention provide rated current to the self-test coil through a standard constant current source unit, calculate the theoretical current according to the rated current, the number of coil turns connected to the self-test coil and the transformation ratio of the leakage transformer, and judge whether the detection current output by the sampling unit is equal to the theoretical current, thereby judging whether the leakage transformer is working normally, and further checking whether the accuracy and linearity of the leakage transformer and the sampling unit meet the requirements.

[0078] Although some specific embodiments of the present invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A leakage monitoring device with remote self-checking function, characterized in that: It is arranged in a street light box-type transformer, the street light box-type transformer includes a total neutral line and a total phase line, and also includes at least one branch, the branch includes an AC contactor, an identification phase line, an identification neutral line and a load, the input end of the identification phase line is connected to the total phase line via the AC contactor, the output end of the identification phase line is connected to the positive pole of the load, the input end of the identification neutral line is connected to the total neutral line via the AC contactor, and the output end of the identification neutral line is connected to the negative pole of the load, including: a main control processor, a control bus, a monitoring platform and branch equipment; The main control processor is connected to the control bus and the monitoring platform respectively; The branch circuit equipment is arranged corresponding to the branch circuit, including a power-off control unit and a leakage transformer: The power-off control unit comprises a first-order relay and a second-order relay, wherein both the first-order relay and the second-order relay are single-pole double-throw relays; the first-order relay comprises a first-order relay common end, a first-order relay normally open end, a first-order relay normally closed end and a first-order relay control end, wherein the first-order relay common end is connected to the total phase line, the first-order relay normally open end is connected to the control end of the AC contactor, and the first-order relay control end is connected to the control bus; the second-order relay comprises a second-order relay common end, a second-order relay normally open end, a second-order relay normally closed end and a second-order relay control end, wherein the second-order relay common end is connected to the total phase line, the second-order relay normally open end is connected to the control end of the AC contactor, and the second-order relay control end is connected to the control bus; the first-order relay normally open end, the first-order relay normally closed end, the second-order relay normally open end and the second-order relay normally closed end are all connected to a voltage detector, wherein the output end of the voltage detector is connected to the input end of a sampling unit, and the output end of the sampling unit is connected to the control bus; The leakage current transformer comprises a magnetic ring, which is sleeved outside the identification neutral line and the identification phase line, and is wound with a detection coil and a self-detection coil, the detection coil and the self-detection coil are non-contact, and the detection coil is connected to the input end of the sampling unit; the self-detection coil comprises at least three interfaces, the number of coil turns between any two adjacent interfaces is an integer, all the interfaces are connected to an interface switching switch, the control end of the interface switching switch is connected to the control bus, and the input end of the interface switching switch is connected to the output end of the standard constant current source unit.

2. The leakage monitoring device with remote self-checking function according to claim 1 is characterized in that: The interface switching switch comprises a primary switch and a secondary switch connected in sequence, the primary switch is connected to the output end of the standard constant current source unit, and the secondary switch is connected to the interface; The primary switch is used to adjust the current output by the standard constant current source unit, and the secondary switch is used to turn on or off the interface.

3. The leakage monitoring device with remote self-checking function according to claim 1, characterized in that: The number of the total phase lines is 3; In any of the power-off control units, the common end of the first-order relay is connected to any one of the total phase lines; the total phase line to which the common end of the second-order relay is connected is the same as the total phase line to which the common end of the first-order relay is connected.

4. A leakage monitoring method with remote self-checking function, characterized in that: The leakage monitoring device with remote self-checking function applied to any one of claims 1 to 3 comprises: a self-checking process and a leakage monitoring process; The self-test process includes the self-test of the power-off control unit, and the self-test of the power-off control unit includes: The main control processor controls the first-order relay to turn on the normally open end of the first-order relay, and the second-order relay to turn on the normally closed end of the second-order relay; the main control processor obtains the first-order relay normally open end voltage fed back by the voltage detector connected to the normally open end of the first-order relay and the second-order relay normally closed end voltage fed back by the voltage detector connected to the normally closed end of the second-order relay; the main control processor controls the first-order relay to turn on the normally closed end of the first-order relay, and the second-order relay to turn on the normally open end of the second-order relay; the main control processor obtains the voltage detector connected to the normally closed end of the first-order relay The first-order relay normally closed end voltage fed back by the voltage detector and the second-order relay normally open end voltage fed back by the voltage detector connected to the second-order relay normally open end; the main control processor determines whether the first-order relay normally open end voltage and the second-order relay normally open end voltage are preset voltages, and whether the first-order relay normally closed end voltage and the second-order relay normally closed end voltage are 0; if the first-order relay normally open end voltage and the second-order relay normally open end voltage are the preset voltages and the first-order relay normally closed end voltage and the second-order relay normally closed end voltage are 0, the main control processor determines that the power-off control unit is working normally; The leakage monitoring process includes: the main control processor obtains the leakage current transmitted by the sampling unit, and transmits the leakage current to the monitoring platform for display.

5. The leakage monitoring method with remote self-checking function according to claim 4 is characterized in that: After the main control processor acquires the leakage current transmitted by the sampling unit, the method further includes: The main control processor determines whether the leakage current is not zero. If the leakage current is not zero, the main control processor determines the corresponding branch according to the leakage current that is not zero, and controls the normally closed end of the first-order relay and the normally closed end of the second-order relay corresponding to the determined branch to be turned on at the same time.

6. The leakage monitoring method with remote self-checking function according to claim 4, characterized in that: The self-test process also includes self-testing the leakage current transformer and the sampling unit, and the self-testing of the leakage current transformer and the sampling unit includes: The main control processor controls the interface switching switch to connect the two interfaces; The main control processor obtains the detection current transmitted by the sampling unit, calculates the theoretical current according to the current output by the standard constant current source unit, the number of coil turns between the two interfaces that are turned on, and the transformation ratio of the leakage transformer, and determines whether the detection current is equal to the theoretical current. If the detection current is equal to the theoretical current, the main control processor determines that the leakage transformer and the sampling unit are operating normally.

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