CN114142444A - Grounding detection protection device - Google Patents
Grounding detection protection device Download PDFInfo
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- CN114142444A CN114142444A CN202111502472.3A CN202111502472A CN114142444A CN 114142444 A CN114142444 A CN 114142444A CN 202111502472 A CN202111502472 A CN 202111502472A CN 114142444 A CN114142444 A CN 114142444A
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- voltage
- grounding
- ground
- detection
- relay
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/26—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
- G01R31/3271—Testing of circuit interrupters, switches or circuit-breakers of high voltage or medium voltage devices
- G01R31/3275—Fault detection or status indication
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/52—Testing for short-circuits, leakage current or ground faults
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H1/00—Details of emergency protective circuit arrangements
- H02H1/0007—Details of emergency protective circuit arrangements concerning the detecting means
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- General Physics & Mathematics (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
The invention provides a grounding detection protection device, which comprises a grounding detection relay fault detection loop, wherein the grounding detection relay is arranged on a wharf high-voltage power distribution cabinet; the ground wire detection circuit is composed of a ground detection circuit and a ground circuit, wherein the ground detection circuit comprises: one end of the high-voltage cable is connected with the grounding detection relay, and the other end of the high-voltage cable is used for respectively penetrating through the wharf high-voltage pit, the high-voltage cable slip ring box and the crane room and grounding; the voltage stabilizing diode is connected in series on the high-voltage cable; the ground line includes: one end of the grounding cable is connected with the grounding detection relay, and the other end of the grounding cable is merged into the high-voltage pit through the isolating device and is communicated with the local ground of the shore bridge; the grounding detection relay acquires the current value of the fault detection circuit and judges whether the fault detection circuit is abnormal or not, and when the fault detection circuit is abnormal, the circuit for supplying power to the upstream equipment is cut off. The device can monitor whether the fault detection loop is abnormal in real time, and cut off the upstream equipment in emergency, so as to ensure safety.
Description
Technical Field
The invention relates to the technical field of high voltage of large crane equipment, in particular to a grounding detection protection device.
Background
At present, the manufacturing industry of large equipment is developed globally, and meanwhile, the safety risk of the production and the use of a large crane also raises a high attention level.
With the iteration of port machines, higher requirements are also placed on the safety protection of the high-voltage system of the shore crane. The high voltage of the shore equipment is basically in the level of ten thousand volts or even more than one hundred thousand volts when in work. A prerequisite for the use of the device is therefore a reliable and safe earthing. This is a necessary safeguard both for the operator and for the equipment itself.
The conventional equipment grounding detection system cannot meet the requirements on the safety of operators and equipment, so that the problems need to be solved urgently.
Disclosure of Invention
In view of the above, the present invention provides a ground fault detection protection device to solve the above technical problems.
In order to solve the above technical problems, the present invention provides a ground fault detection protection device.
In a first aspect, an embodiment of the present invention provides a ground fault detection protection device applied to a quayside and shore crane, including:
the code head side includes: a wharf high-voltage power distribution cabinet and a wharf high-voltage pit;
the shore crane comprises: the wharf high-voltage distribution cabinet is used for connecting the wharf high-voltage pit, the high-voltage cable slip ring box and the crane machine room by taking a high-voltage cable as a high-voltage transmission path;
the ground detection protection device comprises a ground detection relay and a ground fault detection loop electrically connected with the ground detection relay, wherein the fault detection loop comprises a ground detection line and a ground line serving as a reference line;
the grounding detection relay is arranged on the side of the wharf high-voltage power distribution cabinet and is provided with an equipment safety grounding circuit;
the ground detection circuit comprises:
the high-voltage cable is a multi-core cable with a grounding detection wire core and a grounding wire core, one end of the high-voltage cable is connected with the grounding detection relay, and the other end of the high-voltage cable is used for respectively penetrating through the wharf high-voltage pit, the high-voltage cable slip ring box and the crane room and connecting to the local part of the shore bridge;
the voltage stabilizing diode is connected in series with the grounding detection wire core in the high-voltage cable of the crane room;
the ground line includes:
one end of the grounding cable is connected with the grounding detection relay, and the other end of the grounding cable is finally merged into the high-voltage pit through the isolating device and is communicated with the local ground of the shore bridge;
the grounding detection relay obtains the current value of the fault detection loop and judges whether the fault detection loop is abnormal or not according to the current value,
when the ground fault detection circuit is abnormal, the ground detection relay cuts off a circuit for supplying power to upstream equipment.
According to an embodiment of the present application, the ground detection protection device further includes:
a slip ring case opening limiting component which is connected in series with the high-voltage cable and is arranged on a case cover of the slip ring case of the high-voltage cable,
when the fault detection circuit is abnormal, the grounding detection relay cuts off a circuit for supplying power to upstream equipment when the box cover is opened.
According to an embodiment of the present application, the ground detection protection device further includes:
the high-voltage emergency stop component is connected in series on the high-voltage cable fault detection loop and is arranged in the crane room;
when a dangerous situation occurs, for example, when a fire, an earthquake, terrorist activity, war, or other dangerous situation is encountered, the high voltage emergency stop component may be artificially activated, and the ground detection relay cuts off the circuit that powers the upstream equipment.
According to an embodiment of the present application, the apparatus further comprises a zero sequence current detection unit for monitoring whether the state of the high voltage incoming line of the upstream device is unbalanced and short-circuited.
According to an embodiment of the application, the apparatus further comprises:
and the isolation assembly is respectively connected with the wharf common ground bus and the ground line and is used for isolating the equipment safety ground line from the signal ground of the detection unit.
According to an embodiment of the application, the apparatus further comprises:
and the alarm is electrically connected with the grounding detection relay and used for giving an alarm under the condition that the fault detection loop is abnormal.
According to an embodiment of the present application, the ground detection relay includes:
a signal processing relay; the relay is used for acquiring a current value of the fault detection loop and judging whether the fault detection loop is abnormal or not according to the current value; and meanwhile, the circuit is used for outputting a power supply cut-off signal to cut off the power supply for the upstream equipment when the fault detection loop is judged to be abnormal.
According to one embodiment of the application, the zener diode is a zener diode.
According to one embodiment of the application, the source of introduction of the equipment safety ground line is introduced by the dock common ground.
According to one embodiment of the application, the locally grounded lead-in source of the shore bridge is introduced by a high pressure pit and a track.
The technical scheme of the invention has the following beneficial effects:
according to the grounding detection protection device provided by the embodiment of the invention, by arranging the grounding detection relay and the fault detection loop electrically connected with the grounding detection relay, when a dangerous condition is met on the crane, such as: the upstream power supply equipment can be quickly cut off by manually activating a high-voltage tight stop mode under special conditions such as fire, earthquake, terrorist activity, war and the like. Or the case cover is connected in the high-voltage slip ring case on the machine in series and is opened to limit, so that the power supply of upstream equipment can be automatically cut off when a maintainer maintains and maintains the slip ring, and the life safety of related personnel is ensured. In addition, the system plays a real-time monitoring and protection role when serious accidental breakage, high-temperature melting and the like happen to a high-voltage reel cable on a crane or a high-voltage fixed cable in a high-voltage tunnel on the shore, can cut off upstream equipment in an emergency, and has a good protection effect on surrounding personnel and downstream crane equipment.
Drawings
FIG. 1 is a schematic structural view of a quayside and shoreside crane according to one embodiment of the present invention;
fig. 2 is a schematic structural diagram of a ground fault detection protection device according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of the ground fault detection protection device installed in the quayside crane and the shore crane according to an embodiment of the present invention;
fig. 4 is a functional schematic block diagram of a ground fault detection protection device according to an embodiment of the present invention.
Reference numerals
A ground detection protection device 100; a ground detection relay 110; a fault detection loop 120; a ground detection line 121; a ground line 122; a dock common ground bus 130; an equipment safety ground line 140; a high voltage cable 150; an isolation component 160; a high-pressure shut-down assembly 170; the slip ring box opens the limit assembly 180; a zener diode 190.
A wharf high-voltage power distribution cabinet 200; a quay high pressure pit 300; a high voltage cable slip ring box 400; a crane house 500.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the drawings of the embodiments of the present invention. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the invention, are within the scope of the invention.
At present, the grounding detection system of the conventional equipment belongs to a localized passive detection and passive protection mode. For example, such as: the metal shell is grounded with the lead of the metal structure, and the built-in grounding protection function of the onboard high voltage cabinet and the transformer is achieved. Active protection methods for the power supply equipment of the upper stage and some special cases are lacked.
The invention provides a grounding detection protection device, which is used for the active high-voltage grounding detection of a large-scale shore crane of a container terminal, can break through the grounding detection protection scope of a local machine, realizes active detection and feedback aiming at a cable and upstream high-voltage equipment on a high-voltage transmission path, and can cut off a superior power supply under the special condition of the local machine.
The following is a ground fault detection protection device according to an embodiment of the present application with reference to the drawings.
As shown in fig. 1 to 4, the ground fault detection protection device 100 according to the embodiment of the present invention is applied to quay and shore cranes. The code head side includes: a wharf high-voltage power distribution cabinet 200 and a wharf high-voltage pit 300; the shore crane comprises: the high-voltage cable slip ring box 400 and the crane room 500, the wharf high-voltage power distribution cabinet 200 is used for connecting the wharf high-voltage pit 300, the high-voltage cable slip ring box 400 and the crane room 500 by using the high-voltage cable 150 as a high-voltage transmission path.
As shown in fig. 2, the ground fault detection protection device 100 includes a ground detection relay 110 and a fault detection circuit 120 electrically connected to the ground detection relay 110, the fault detection circuit includes a ground detection line 121 (GC) and a ground line 122(G), wherein the ground line 122 constitutes the fault detection circuit 120 together with the ground detection line 121 as a reference line, one end of an equipment safety ground line 140(SPG) is electrically connected to a protection ground terminal of the ground detection relay 110, respectively, and the other end is connected to a dock common ground bus for safety protective grounding to the ground detection relay 110.
As shown in fig. 1 to 3, the ground fault detection relay 110 is configured to be disposed on the side of the wharf high-voltage power distribution cabinet 200; the ground line monitoring circuit includes a high voltage cable 150 and a zener diode 190. One end of the grounding detection wire core of the high-voltage cable 150 is electrically connected with the grounding detection relay 110, and the other end of the grounding detection wire core is respectively arranged in the wharf high-voltage pit 300, the high-voltage cable slip ring box 400 and the crane room 500 in a penetrating manner and is connected with a component of the voltage stabilizing diode 190; the zener diode 190 is connected in series to the ground detection line 121, is located on the high voltage cable 150 of the crane room 500, and is connected to the shore bridge. Before the circuit is grounded, the components of the zener diode 190 are connected in series, so that the system can detect whether the fault detection circuit 120 is in an open circuit (high resistance) or short circuit (low resistance) state through the ground detection relay 110, immediately determine that the circuit is invalid (fault), and cut off the circuit for supplying power to the upstream equipment. For example, the ground trip protection coil of the power distribution cabinet is directly driven to be activated within 250ms of the detection of the abnormality by the ground detection relay 110, and the power supply is cut off, or the occurrence of the fault can be indicated by a fault lamp. The zener diode 190 is preferably a zener diode, where the characteristic of reverse breakdown of the PN junction of the zener diode (zener diode) is utilized to enable measurement independent of unwanted external conditions, and this passive characteristic allows induced current to circulate in the ground loop and perform very stably and reliably, especially suitable for use in shore crane installations with slip ring mechanisms. The ground detection relay 110 acquires the current value of the fault detection circuit 120 and determines whether the fault detection circuit 120 is abnormal according to the current value, and when the fault detection circuit 120 is abnormal, the ground detection relay 110 cuts off the circuit for supplying power to the upstream device.
That is, upon detection, a reference resistance value (e.g., a loop impedance of no greater than 28 Ω) will be generated in the fault detection loop 120 by applying a reasonable DC voltage (e.g., +24V or +30V) to the fault detection loop 120, which in turn will generate a reference loop current (0.5A-12.5A) in the loop. If the fault detection circuit 120 is opened or short-circuited due to an abnormality, the loop current value will be abnormal, and the ground detection relay 110 will determine that the loop is failed and cut off the upstream circuit in time. The system plays a real-time monitoring and protection role in the conditions of serious accidental breakage, high-temperature melting and the like of a high-voltage reel cable on a crane or a high-voltage fixed cable in a high-voltage tunnel on the shore. Once a fault occurs, the power supply circuit of the upstream equipment can be automatically cut off, the personal safety of surrounding personnel and the downstream crane equipment are well protected, and the safety of the whole high-voltage system is ensured.
According to an embodiment of the present invention, the ground fault detection protection device 100 further comprises: the slip ring box opening limit component 180 is connected in series to the ground detection circuit 121 through the high-voltage cable 150, and is disposed on a box cover of the high-voltage cable slip ring box 400, and when the case cover is opened in case of abnormality of the fault detection circuit 120, the ground detection relay 110 cuts off a circuit for supplying power to an upstream device. The case cover is connected in the high-voltage slip ring case on the machine in series to be opened for limiting, and when a maintainer maintains and maintains the slip ring, the power supply of upstream equipment is automatically cut off, so that the life safety of related personnel is ensured.
According to an embodiment of the present invention, the ground fault detection protection device 100 further comprises: the high-voltage emergency stop assembly 170 is connected in series on the ground detection line 121, and is arranged in the crane room 500; when the associated authorized personnel determine that an emergency situation is present, manual depression of the high voltage emergency stop assembly 170 causes the ground fault detection circuit to be manually triggered. The invention adopts high-pressure emergency stop configured on the machine room, and when the crane really encounters dangerous conditions, such as: the upstream power supply equipment is quickly cut off by activating high-voltage emergency stop under special conditions such as fire, earthquake, terrorist activity, war and the like.
According to an embodiment of the present invention, as shown in fig. 2 and fig. 4, the apparatus further includes a zero sequence current detection unit, which is used for monitoring whether the state of the high voltage incoming line of the upstream equipment is unbalanced and short-circuited.
According to the zero sequence current method of the invention, the state of the high-voltage incoming line at the power distribution side of the code head is detected, namely, the corresponding grounding detection relay 110 is matched, the relay also integrates the zero sequence current detection function, detects the fundamental frequency and the zero sequence current, and verifies whether the zero sequence current is balanced or short-circuited through the current value (signal) obtained by the zero sequence current detection unit. And can cut off the upstream high voltage (direct trip) and also can simultaneously alarm the fault (zero sequence current fault indication).
According to an embodiment of the present application, the ground detection protection device 100 further includes: and the isolation assembly 160, the isolation assembly 160 is respectively connected with the dock common ground bus 130 and the ground line 122, and is used for isolating the equipment safety ground and the signal ground of the detection unit and having the function of high-voltage arc extinction.
According to an embodiment of the present application, the ground detection protection device 100 further includes: and a trip indicator (not shown) connected to the ground detection relay for displaying a trip state after the upstream power supply is cut off in an abnormal condition.
According to an embodiment of the application, the ground detection protection further comprises: and an alarm electrically connected to the ground detection relay 110 for issuing an alarm in case that the fault detection circuit 120 is abnormal.
According to an embodiment of the present application, the ground detection relay 110 includes: a signal processing relay; namely, the ground fault relay 110, which is used to obtain the current value of the fault detection circuit 120 and determine whether the fault detection circuit 120 is abnormal according to the current value; when the failure detection circuit 120 is determined to be abnormal, a power-off signal is output to cut off the circuit that supplies power to the upstream device. Meanwhile, the device has the function of detecting zero sequence current and monitors the state of an inlet wire power supply of upstream equipment.
According to one embodiment of the present application, the source of the introduction of the equipment safety ground line 140 is introduced by the dock common ground.
According to one embodiment of the application, the source of local grounding of the shore bridge is introduced by the high-pressure pits and tracks.
According to the ground fault detection protection device 100 of the embodiment of the present application, a high-voltage knife switch equipped with a trip coil, a zero sequence current sensing unit, a ground fault detection relay 110, a ground line isolation assembly 160, a trip indicator, a slip ring box with a ground fault detection ring and a cover plate opening limit, a high-voltage emergency stop, and a zener tube type terminal assembly (zener diode) are sequentially used from a dock side to a crane. The devices are traversed by high voltage cables 150 with ground sense cores to minimize the devices. And under the condition of abnormality, the power supply circuit of the upstream equipment is cut off in time, and the safety of the whole system is ensured.
Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. The use of "first," "second," and similar terms in the present application do not denote any order, quantity, or importance, but rather the terms are used to distinguish one element from another. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships are changed accordingly.
The foregoing is a preferred embodiment of the present invention, and it should be noted that it is obvious to those skilled in the art that various modifications and improvements can be made without departing from the principle of the present invention, and these modifications and improvements should be construed as the protection scope of the present invention.
Claims (10)
1. A grounding detection protection device is applied to a wharf side and a shore side crane and is characterized in that,
the code head side includes: a wharf high-voltage power distribution cabinet and a wharf high-voltage pit;
the shore crane comprises: the wharf high-voltage power distribution cabinet is used for connecting the wharf high-voltage pit, the high-voltage cable slip ring box and the crane machine room by taking a high-voltage cable as a high-voltage transmission path;
the ground detection protection device comprises a ground detection relay and a fault detection loop electrically connected with the ground detection relay, wherein the fault detection loop comprises a ground detection line and a ground line serving as a reference line;
the grounding detection relay is arranged on the side of the wharf high-voltage power distribution cabinet and is provided with an equipment safety grounding circuit;
the ground detection circuit comprises:
the high-voltage cable is a multi-core cable with a grounding detection wire core and a grounding wire core, one end of the high-voltage cable is connected with the grounding detection relay, and the other end of the high-voltage cable is used for respectively penetrating through the wharf high-voltage pit, the high-voltage cable slip ring box and the crane room and connecting to the local part of the shore bridge;
the voltage stabilizing diode is connected in series with the grounding detection wire core in the high-voltage cable of the crane room;
the ground line includes:
one end of the grounding cable is connected with the grounding detection relay, and the other end of the grounding cable is merged into the high-voltage pit through the isolating device and is communicated with the local ground of the shore bridge;
the grounding detection relay obtains the current value of the fault detection loop and judges whether the fault detection loop is abnormal or not according to the current value,
when the fault detection circuit is abnormal, the ground detection relay cuts off a circuit for supplying power to upstream equipment.
2. The apparatus of claim 1, wherein the ground detection protection device further comprises:
the slip ring box opening limiting component is connected in series with the high-voltage cable and is arranged on the box cover of the slip ring box of the high-voltage cable,
when the case lid is opened in the event of an abnormality in the fault detection circuit, the ground detection relay cuts off the circuit for supplying power to the upstream equipment.
3. The apparatus of claim 1 or 2, wherein the ground detection protection apparatus further comprises:
the high-voltage emergency stop component is connected in series on the high-voltage cable fault detection loop and is arranged in the crane room;
when a dangerous condition occurs, the ground detection relay cuts off the circuit that supplies power to the upstream equipment by activating the high voltage emergency stop component.
4. The apparatus of claim 1, further comprising a zero sequence current detection unit for monitoring whether the state of the upstream equipment high voltage incoming line is unbalanced and short-circuited.
5. The apparatus of claim 1, further comprising:
and the isolation assembly is respectively connected with the wharf common grounding bus and the grounding line and is used for isolating the equipment safety grounding line from the signal grounding of the detection unit.
6. The apparatus of claim 1, further comprising:
and the alarm is electrically connected with the grounding detection relay and used for giving an alarm under the condition that the fault detection loop is abnormal.
7. The apparatus of claim 1, wherein the ground detection relay comprises:
a signal processing relay; the relay is used for acquiring a current value of the fault detection loop and judging whether the fault detection loop is abnormal or not according to the current value; and meanwhile, the circuit is used for outputting a power supply cut-off signal to cut off the power supply for the upstream equipment when the fault detection loop is judged to be abnormal.
8. The apparatus of claim 1, wherein the zener diode is a zener diode.
9. The apparatus of claim 1, wherein the source of the equipment safety ground line is introduced from a dock common ground.
10. The apparatus of claim 1, wherein the locally grounded source of the shore bridge is introduced by a high pressure pit and a track.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111502472.3A CN114142444A (en) | 2021-12-09 | 2021-12-09 | Grounding detection protection device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111502472.3A CN114142444A (en) | 2021-12-09 | 2021-12-09 | Grounding detection protection device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114142444A true CN114142444A (en) | 2022-03-04 |
Family
ID=80385509
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111502472.3A Pending CN114142444A (en) | 2021-12-09 | 2021-12-09 | Grounding detection protection device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114142444A (en) |
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2021
- 2021-12-09 CN CN202111502472.3A patent/CN114142444A/en active Pending
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