CN112003252A - Line fault removing device and direct current system - Google Patents
Line fault removing device and direct current system Download PDFInfo
- Publication number
- CN112003252A CN112003252A CN202010838132.7A CN202010838132A CN112003252A CN 112003252 A CN112003252 A CN 112003252A CN 202010838132 A CN202010838132 A CN 202010838132A CN 112003252 A CN112003252 A CN 112003252A
- Authority
- CN
- China
- Prior art keywords
- current
- fault
- electrically connected
- direct current
- circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000009471 action Effects 0.000 claims abstract description 9
- 230000001012 protector Effects 0.000 claims description 17
- 238000001514 detection method Methods 0.000 claims description 13
- 230000005611 electricity Effects 0.000 claims description 5
- 238000012423 maintenance Methods 0.000 claims description 4
- 230000000694 effects Effects 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 9
- 238000005516 engineering process Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
Images
Classifications
-
- 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
- H02H7/268—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 for dc systems
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The utility model relates to a line fault remove device and direct current system, line fault remove device is through being provided with current generation equipment, when short-circuit fault takes place for arbitrary branch road, current generation equipment can produce trouble holding current, trouble holding current passes through direct current bus flows in the branch road that takes place short-circuit fault to the short-circuit current on the branch road of maintaining the trouble, thereby makes on the trouble branch road the circuit breaker action, with the short-circuit fault on cutting off this branch road. According to the embodiment of the application, the technical problem that the current direct current system is poor in working stability in the prior art is solved by the current generating device, and the technical effect of improving the working stability of the direct current system is achieved.
Description
Technical Field
The application relates to the technical field of power grid fault safety, in particular to a line fault removing device and a direct current system.
Background
At present, a direct current system generally comprises a direct current bus and branches, and each branch is generally provided with a converter. With the increasing development of the direct current system, the fault protection of the converter in each branch is improved, the converter can rapidly enter a short-circuit protection state when facing short-circuit faults, each branch is generally provided with a circuit breaker for the sake of safety, the short-circuit protection action time of the converter is far shorter than the action time of the circuit breaker, when the branch has the short-circuit faults, the converter stops working, but the circuit breaker is not disconnected in time, and the faults cannot be eliminated in time. When the dc system is powered on again, since the fault of the faulty branch is not eliminated yet, the other branches that are not faulty still enter the short-circuit protection and cannot work normally, so the working stability of the current dc system is poor.
Disclosure of Invention
Accordingly, it is necessary to provide a line fault clearing device and a dc system for solving the problem of poor operation stability of the conventional dc system.
The utility model provides a line fault remove device, is applied to direct current system, direct current system includes direct current bus and many branch roads, parallelly connected between many branch roads, and respectively with direct current bus electricity is connected, and every branch road is provided with the circuit breaker and the converter of establishing ties, line fault remove device includes:
and the current generating equipment is electrically connected with the direct current bus and used for generating fault maintaining current, and the intensity of the fault maintaining current is not less than that of each branch circuit short-circuit current.
In one embodiment, the current generating apparatus includes:
an alternating current power supply for generating the fault-sustaining alternating current;
the input end of the rectifier is electrically connected with the alternating current power supply, the output end of the rectifier is electrically connected with the direct current bus, and the rectifier is used for converting the fault maintenance alternating current into the fault maintenance current.
In one embodiment, the ac power source is a single-phase ac power source.
In one embodiment, the method further comprises the following steps:
and the input end of the transformer is electrically connected with the alternating current power supply, and the output end of the transformer is electrically connected with the rectifier.
In one embodiment, the rectifier comprises:
the anode of the first diode component is electrically connected with the alternating current power supply, and the cathode of the first diode component is electrically connected with the anode of the direct current bus;
and the cathode of the second diode component is electrically connected with the alternating current power supply, and the anode of the second diode component is electrically connected with the cathode of the direct current bus.
In one embodiment, the ac power source is a three-phase ac power source;
the first diode assembly comprises three first diodes, anodes of the three first diodes are respectively electrically connected with the three phases of the alternating current power supply, and cathodes of the three first diodes are electrically connected with the anode of the direct current bus;
the second diode assembly comprises three second diodes, the anodes of the three second diodes are respectively connected with the three-phase electricity of the alternating current power supply, and the cathodes of the three second diodes are electrically connected with the cathode of the direct current bus.
A direct current system comprising:
the direct current bus comprises a positive electrode wire and a negative electrode wire,
the multiple branches are connected in parallel and are respectively and electrically connected with the direct current bus, and each branch is provided with a circuit breaker and a converter which are connected in series;
in the line fault removing apparatus, the current generating device is electrically connected to the dc bus, and is configured to generate a fault holding current, where the intensity of the fault holding current is not less than the intensity of the short-circuit current of each branch.
In one embodiment, the converter comprises:
a converter body;
and one end of the protector is electrically connected with the circuit breaker, the other end of the protector is electrically connected with the converter body, and the protector is used for controlling the converter body to stop working when the current flowing through the converter body exceeds a preset threshold value.
In one embodiment, the protector comprises:
the current detection assembly is electrically connected with the converter body and is used for detecting the current flowing through the converter body;
and the control assembly is respectively in signal connection with the converter body and the current detection assembly and is used for controlling the converter body to stop working when the current flowing through the converter body exceeds a preset threshold value.
In one embodiment, the method further comprises the following steps:
and the central control equipment is in signal connection with the circuit breakers respectively and is used for determining whether the branches have faults or not according to the action states of the circuit breakers and determining the fault branch when the branches have the faults.
The line fault removing device provided by the embodiment of the application is provided with the current generating equipment, when any branch circuit has a short-circuit fault, the current generating equipment can generate fault maintaining current, the fault maintaining current flows into the branch circuit with the short-circuit fault through the direct-current bus to maintain the short-circuit current on the fault branch circuit, so that the breaker on the fault branch circuit acts to cut off the short-circuit fault on the branch circuit. According to the embodiment of the application, the technical problem that the current direct current system is poor in working stability in the prior art is solved by the current generating device, and the technical effect of improving the working stability of the direct current system is achieved.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments or the conventional technologies of the present application, the drawings used in the descriptions of the embodiments or the conventional technologies will be briefly introduced below, it is obvious that the drawings in the following descriptions are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a line fault clearing apparatus and an application environment thereof according to an embodiment of the present application;
fig. 2 is a schematic structural diagram of a current generation device in a line fault clearing apparatus according to an embodiment of the present application;
fig. 3 is a schematic structural diagram of a rectifier in the line fault clearing apparatus according to an embodiment of the present application;
fig. 4 is a schematic structural diagram of a line fault clearing apparatus and an application environment thereof according to an embodiment of the present application;
FIG. 5 is a schematic diagram of a portion of a line fault clearing apparatus according to an embodiment of the present application;
fig. 6 is a schematic structural diagram of a dc system according to an embodiment of the present application;
FIG. 7 is a schematic diagram of a converter in a DC system according to an embodiment of the present application;
fig. 8 is a schematic structural diagram of a protector in a dc system according to an embodiment of the present application;
fig. 9 is a schematic structural diagram of a dc system according to an embodiment of the present application.
Description of reference numerals:
10. a line fault removal device;
100. a current generating device;
110. an alternating current power supply;
120. a rectifier;
121. a first diode component;
1211. a first diode;
122. a second diode assembly;
1221. a second diode;
200. a transformer;
30. a direct current system;
300. a direct current bus;
400. a branch circuit;
410. a circuit breaker;
420. a converter;
421. a converter body;
422. a protector;
4221. a current detection component;
4222. a control component;
500. and (4) a central control device.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more clearly understood, a line fault clearing device and a dc system of the present application are described in further detail below by embodiments and with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
The numbering of the components as such, e.g., "first", "second", etc., is used herein only to distinguish the objects as described, and does not have any sequential or technical meaning. The term "connected" and "coupled" when used in this application, unless otherwise indicated, includes both direct and indirect connections (couplings). In the description of the present application, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present application and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be considered as limiting the present application.
In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
Referring to fig. 1, the present embodiment provides a line fault removing device 10, which can be applied to a dc system 30 for removing a short-circuit fault in the dc system 30. The dc system 30 generally includes a dc bus 300 and a plurality of branches 400, the plurality of branches 400 are connected in parallel and are electrically connected to the dc bus 300, respectively, and each branch 400 is provided with a circuit breaker 410 and an inverter 420 connected in series. When a short-circuit fault occurs in a certain branch circuit 400, the line fault removing apparatus 10 removes the line fault of the faulty branch circuit 400 by generating a fault maintaining current to operate the circuit breaker 410. The following embodiments are described in detail by taking the application of the line fault cutting apparatus 10 to the dc system 30 as an example.
One embodiment of the present application provides a line fault clearing apparatus 10, including: the current generating device 100.
The current generating device 100 is electrically connected to the dc bus 300, and is configured to generate a fault holding current, where the magnitude of the fault holding current is not less than the magnitude of the short-circuit current of each branch circuit 400. The current generating device 100 may be a fixed power supply, a mobile power supply, or other voltage with stable large current output. The fault holding current may be determined according to the historical data of the daily short-circuit fault current of the plurality of branches 400, such as 80A, 106A, and the like, or may be determined according to real-time measurement, which is not limited in this embodiment, and may be specifically selected or set according to actual requirements. The fault holding current may be fixed or adjustable, for example, the fault holding current with different intensities is determined according to the short-circuit current when the short-circuit fault occurs in each branch 400 according to the difference of the load on each branch 400.
The working principle of the line fault removing device 10 provided by the embodiment of the application is as follows:
the embodiment of the application provides a line fault removing device 10 which comprises a current generating device 100. When the dc bus 300 is normally operated, the plurality of branches 400 are also normally operated, and when a short-circuit fault occurs in one of the branches 400, the current on the branch 400 is instantaneously increased to generate a short-circuit current. The action time of the circuit breaker 410 is much longer than that of the inverter 420, so that once a short-circuit current occurs, the inverter 420 acts first, automatically shuts down, and starts a protection mode, so that the circuit breaker 410 is not operated, the short-circuit current on the branch 400 is cleared, and the circuit breaker 410 is not operated, which means that the short-circuit fault on the branch 400 is not cut off. Once the line is powered up again, the short-circuit fault of the branch circuit 400 still exists, and most of the current on the dc bus 300 flows into the faulty branch circuit 400, so that other fault-free branch circuits 400 cannot work normally. In this embodiment, the current generating device 100 is provided with the current generating device 100, the current generating device 100 may generate a fault maintaining current, the current generating device 100 is electrically connected to the dc bus 300 to provide the fault maintaining current for the dc bus 300 and the fault branch 400, the fault maintaining current flows into different branches 400 through the dc bus 300, and most of the current flows into the branch 400 with the short-circuit fault, so as to maintain the short-circuit current of the branch 400 with the short-circuit fault, so that the circuit breaker 410 operates to remove the short-circuit fault on the branch 400. When the line is powered up again, the breaker 410 is opened, the short-circuit fault is cut off, and other branches 400 can continue to work normally, so that the normal and stable work of the line can be maintained.
In the embodiment of the present application, by providing the current generating device 100, when a short-circuit fault occurs in any branch circuit 400, the current generating device 100 may generate a fault maintaining current, and the fault maintaining current flows into the branch circuit 400 with the short-circuit fault through the dc bus 300 to maintain the short-circuit current on the fault branch circuit 400, so that the circuit breaker 410 on the fault branch circuit 400 operates to break the short-circuit fault on the branch circuit 400. The embodiment of the application is provided with the current generation device 100, so that the technical problem that the current direct current system 30 in the prior art is poor in working stability is solved, and the technical effect of improving the working stability of the direct current system 30 is achieved.
Referring to fig. 2, in one embodiment, the current generating apparatus 100 includes: an ac power source 110 and a rectifier 120.
The ac power source 110 is used to generate fault-sustaining ac power. Alternating current power supply 110 can be for direct current bus 300 provides stable electric current, and conveniently acquires, for example can directly get the electricity from the electric wire netting, or adopts portable generating equipment such as hand generator direct power generation, and the flexibility is high. The output voltage of the ac power supply 110 may be 110V, 220V, etc., and this embodiment is not limited at all, and only needs to satisfy the function of providing stable ac power.
The input end of the rectifier 120 is electrically connected to the ac power source 110, the output end of the rectifier 120 is electrically connected to the dc bus 300, the rectifier 120 is configured to convert ac power into dc power, and in this embodiment, the rectifier 120 is configured to convert the fault-maintaining ac power into the fault-maintaining ac power, so as to be conveniently provided to the dc bus 300 for maintaining short-circuit current in the short-circuit fault branch. The rectifier 120 may be a conventional silicon rectifier, which has a mature technology and a relatively low price, and the rectifier 120 may also be another type of rectifier, and in this embodiment, no limitation is made on the specific model, type, and the like of the rectifier 120, and the rectifier may be specifically selected according to actual conditions, and only the function of converting the fault-maintaining alternating current into the fault-maintaining current needs to be satisfied.
Referring to fig. 3, in one embodiment, the rectifier 120 includes: a first diode assembly 121 and a second diode assembly 122.
The anode of the first diode assembly 121 is electrically connected to the ac power source 110, and the cathode of the first diode assembly 121 is electrically connected to the anode of the dc bus 300. The first diode component 121 may include a plurality of diodes, and the plurality of diodes may be connected in parallel or sequentially connected in series, and when the plurality of diodes are connected in parallel, anodes of the plurality of diodes are all electrically connected to the ac power source 110, and cathodes of the plurality of diodes are all electrically connected to an anode of the dc bus 300. Therefore, when the dc bus 300 works normally, each branch 400 has a load, and the potential at the end of the dc bus 300 is higher than that at the end of the current generating device 100, so that the current at the end of the dc bus 300 cannot flow back to the end of the current generating device 100. Only when the end of the dc bus 300 has a short-circuit fault, the load at the end of the branch circuit 400 is reduced, and the potential at the end of the dc bus 300 is lower than the potential of the current generating device 100, so that the fault maintaining current generated by the current generating device 100 can flow to the dc bus 300, thereby maintaining the short-circuit current of the fault branch circuit 400, and the circuit breaker 410 can operate to remove the line fault of the fault branch circuit 400. The diode may be a contact diode, a surface contact diode, a planar diode, etc., and this embodiment is not particularly limited and may be specifically selected according to the actual situation.
The cathode of the second diode assembly 122 is electrically connected to the ac power source 110, and the anode of the second diode assembly 122 is electrically connected to the cathode of the dc bus 300. The second diode assembly 122 may include a plurality of diodes, which may be connected in parallel or sequentially connected in series, and when the plurality of diodes are connected in parallel, anodes of the plurality of diodes are all electrically connected to the cathode of the dc bus 300, and cathodes of the plurality of diodes are all electrically connected to the ac power source 110. The second diode assembly 122 is used for maintaining unidirectional conduction of a circuit, so that current can flow from the negative electrode of the dc bus 300 to the ac power source 110 in a unidirectional manner, thereby forming a unidirectional loop and preventing current from flowing back, so as to ensure the stability of the operation of the current generating apparatus 100 and the whole loop. The diode may be a contact diode, a surface contact diode, a planar diode, or the like, and this embodiment is not particularly limited, and may be specifically selected according to an actual situation, and only needs to satisfy a function of maintaining unidirectional conduction of the loop.
In one embodiment, the ac power source 110 may be a single-phase ac power source 110, that is, one line extracted from a three-phase ac power source in a power grid system is used as a phase line, and the other line is used as a zero line, the phase line and the zero line form a loop through a load, and then a line is grounded and used as a ground, the phase line and the zero line form a loop to provide a stable power supply for the dc bus 300, and a ground line is grounded and used for protection. The single-phase alternating-current power supply 110 has wide source range and safe use, such as a household 220V alternating-current power supply and the like, and has high flexibility.
Referring to fig. 4, in an embodiment, the ac power source 110 is a three-phase ac power source 110, the first diode assembly 121 includes three first diodes 1211, anodes of the three first diodes 1211 are respectively electrically connected to three phases of the ac power source 110, and cathodes of the three first diodes 1211 are electrically connected to an anode of the dc bus 300. The second diode assembly 122 includes three second diodes 1221, anodes of the three second diodes 1221 are respectively connected to the three-phase power of the ac power source 110, and cathodes of the three second diodes 1221 are electrically connected to the cathode of the dc bus 300. The three-phase ac power supply 110 may generate a rotating magnetic field, and may save wires for power transmission, so as to reduce cost, may use an asynchronous motor or the like to supply power, and has high flexibility, and meanwhile, the three-phase ac power supply 110 does not exclude power supply to a single-phase load, and has strong compatibility, and the application range and the use flexibility of the line fault removing device 10 according to the present embodiment may be greatly improved by the three-phase ac power supply. The first diode 1211 and the second diode 1221 may be any one or a combination of a contact diode, a surface contact diode, and a planar diode, and this embodiment is not particularly limited and may be specifically selected according to actual situations.
Referring to fig. 5, in an embodiment, the line fault removing apparatus 10 further includes: a transformer 200.
The input end of the transformer 200 is electrically connected to the ac power source 110, the output end of the transformer 200 is electrically connected to the rectifier 120, and the transformer 200 is configured to convert the voltage of the ac power source 110 into a predetermined voltage, that is, a voltage required to generate the fault-maintaining current. The preset voltage is set according to actual conditions, different adjustments are made by matching with loads of different direct current systems 30, and the adaptability and the application range of the fault removal device can be greatly improved through the transformer 200.
Referring to fig. 6, an embodiment of the present application provides a dc system 30, including: direct current bus 300, branch 400, line fault cut-off 10.
The dc bus 300 refers to a dc common bus in an electric system, and belongs to a driving system in the electric system. The dc bus 300 generally includes two wires: a positive line and a negative line. The dc system 30 is generally an independent power supply, is not affected by the running mode of the generator and the generator system for the power plant, and can ensure that the backup power supply or the storage battery continues to provide dc voltage under the condition that the external ac power is interrupted. The dc bus 300 connects the external power source to the system loads to form a local topology network, which provides current to each load in the power system. The direct current bus 300 can be a plastic power cable, a high-medium low-voltage cross-linked cable and the like, the plastic power cable and the high-medium low-voltage cross-linked cable can be buried underground, the cross section is large, high-voltage and ultrahigh-voltage remote power transmission can be supported, the application range is wider, and the application range of the direct current system 30 in the embodiment is widened. In this embodiment, the type or the number of the dc bus 300 is not limited at all, and may be specifically selected according to actual situations.
The number of the branch circuits 400 is multiple, the plurality of branch circuits 400 are connected in parallel, each branch circuit 400 is electrically connected to the dc bus 300, and each branch circuit 400 is independent from each other. Each of the branches 400 is an independent line with different loads to perform different functions, but each of the branches 400 is provided with a circuit breaker 410 and a converter 420 connected in series, and the converter 420 is connected in series with different numbers and different types of loads. The breaker 410 is used for timely breaking and cutting off the short-circuit fault when the short-circuit fault occurs to the branch circuit 400, so as to protect the branch circuit 400 from being damaged or even burnt out due to the short-circuit current. The converter 420 is used for performing DC-DC conversion, and the converter 420 converts the current on the DC bus 300 into an operating current required by the load on the branch 400, so as to ensure the operating stability of the load on the branch 400.
The line fault cutting device 10 includes a current generating device 100, wherein the current generating device 100 is electrically connected to the dc bus 300, and is configured to generate a fault maintaining current, the strength of which is not less than the strength of the short-circuit current of each of the branches 400, so as to provide the fault branches 400 with an actuating current. The beneficial effects of the line fault clearing device 10 are already explained in the above embodiments, and the description of the embodiment is omitted.
Referring to fig. 7, in one embodiment, the converter 420 includes: a transducer body 421 and a protector 422.
The converter body 421 converts the ac power on the dc bus 300 into the working current required by the load on the branch circuit 400, so as to ensure the working stability of the load on the branch circuit 400. The converter body 421 can realize four-quadrant operation without an intermediate direct-current energy storage link, has excellent input current waveform and output voltage waveform, freely controllable power factor and high flexibility. In this embodiment, the specific type and model of the converter body 421 are not limited, and may be selected according to actual conditions, and only the function of converting the ac power on the dc bus 300 into the working current required by the load on the branch 400 is required to be satisfied.
One end of the protector 422 is electrically connected to the circuit breaker 410, and the other end of the protector 422 is electrically connected to the converter body 421, and the protector 422 is configured to control the converter body 421 to stop working when a current flowing through the converter body 421 exceeds a preset threshold. The protector 422 may be a fuse, a circuit breaker, or the like, and automatically stops the operation of the converter body 421 when the current of the branch 400 exceeds a preset threshold. In this embodiment, the type and the model of the protector 422 are not limited arbitrarily, and may be specifically selected according to actual conditions, and only the function of controlling the converter body 421 to stop working when the current flowing through the converter body 421 exceeds a preset threshold needs to be satisfied.
Referring to fig. 8, in one embodiment, the protector 422 includes: current detection component 4221 and control component 4222.
The current detection assembly 4221 is electrically connected to the transducer body 421, and is configured to detect a current flowing through the transducer body 421. The current detection component 4221 can be an ammeter, is connected in the branch 400 in series and is used for detecting the current in the branch 400, and is low in cost and easy to popularize. The current detection assembly 4221 can also be a current transformer, so that large current can be conveniently measured. The current detection assembly 4221 may also be other electronic devices with a current detection function, and in this embodiment, the current detection assembly 4221 is not specifically limited, and may be specifically selected according to actual conditions, and only needs to satisfy a function of detecting a current flowing through the converter body 421.
The control component 4222 is in signal connection with the converter body 421 and the current detection component 4221, respectively, and is configured to control the converter body 421 to stop operating when a current flowing through the converter body 421 exceeds a preset threshold value, so as to protect the converter body 421 from being damaged by a short-circuit current. The preset threshold may be set according to actual conditions, and this embodiment is not particularly limited. The controller may be a microprocessor, a control chip, a PLC chip, or the like, and the control component 4222 is not limited in this embodiment, and may be specifically selected according to actual conditions, and is limited to a function of controlling the converter body 421 to stop operating when the current flowing through the converter body 421 exceeds a preset threshold.
Referring to fig. 9, in an embodiment, the dc system 30 further includes: the central control device 500.
The central control device 500 is respectively in signal connection with a plurality of circuit breakers 410, and the central control device 500 is configured to determine whether a plurality of branches 400 have a fault according to the action state of the circuit breakers 410 and determine a fault branch 400 when the fault occurs. For example, if the circuit breaker 410 of one branch circuit 400 is activated, it can be determined that the short-circuit fault occurs in the branch circuit 400, and if the other branch circuits 400 are not activated, it can be determined that the short-circuit fault does not occur in the other branch circuits 400. The central control device 500 can complete fault line selection through the action state of the circuit breaker 410, and the method is simple and easy to operate. The control device may be any electronic device having a data processing function, such as a processor, a server, a mobile phone, a control chip, and the like, and the present embodiment is not particularly limited, and only needs to satisfy the functions of determining whether the plurality of branches 400 have a fault according to the action state of the circuit breaker 410 and determining the faulty branch 400 when the fault occurs.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. The utility model provides a line fault remove device, is applied to direct current system, direct current system includes direct current bus and many branch roads, parallelly connected between many branch roads, and respectively with direct current bus electricity is connected, and every branch road is provided with the circuit breaker and the converter of establishing ties, its characterized in that, line fault remove device includes:
and the current generating equipment is electrically connected with the direct current bus and used for generating fault maintaining current, and the intensity of the fault maintaining current is not less than that of each branch circuit short-circuit current.
2. The line fault cut-off device of claim 1, wherein the current generating apparatus comprises:
an alternating current power supply for generating the fault-sustaining alternating current;
the input end of the rectifier is electrically connected with the alternating current power supply, the output end of the rectifier is electrically connected with the direct current bus, and the rectifier is used for converting the fault maintenance alternating current into the fault maintenance current.
3. The line fault clearing apparatus of claim 2, wherein said ac power source is a single phase ac power source.
4. The line fault cut-off device of claim 2, further comprising:
and the input end of the transformer is electrically connected with the alternating current power supply, and the output end of the transformer is electrically connected with the rectifier.
5. The line fault cut-off device of claim 2, wherein the rectifier comprises:
the anode of the first diode component is electrically connected with the alternating current power supply, and the cathode of the first diode component is electrically connected with the anode of the direct current bus;
and the cathode of the second diode component is electrically connected with the alternating current power supply, and the anode of the second diode component is electrically connected with the cathode of the direct current bus.
6. The line fault clearing apparatus of claim 5, wherein said ac power source is a three-phase ac power source;
the first diode assembly comprises three first diodes, anodes of the three first diodes are respectively electrically connected with the three phases of the alternating current power supply, and cathodes of the three first diodes are electrically connected with the anode of the direct current bus;
the second diode assembly comprises three second diodes, the anodes of the three second diodes are respectively connected with the three-phase electricity of the alternating current power supply, and the cathodes of the three second diodes are electrically connected with the cathode of the direct current bus.
7. A direct current system, comprising:
the direct current bus comprises a positive electrode wire and a negative electrode wire,
the multiple branches are connected in parallel and are respectively and electrically connected with the direct current bus, and each branch is provided with a circuit breaker and a converter which are connected in series;
the line fault clearing apparatus according to any one of claims 1 to 6, said current generating device being electrically connected to said DC bus for generating a fault holding current, said fault holding current having a magnitude not less than a magnitude of each of said branch short circuit currents.
8. The dc system of claim 7, wherein the converter comprises:
a converter body;
and one end of the protector is electrically connected with the circuit breaker, the other end of the protector is electrically connected with the converter body, and the protector is used for controlling the converter body to stop working when the current flowing through the converter body exceeds a preset threshold value.
9. The direct current system of claim 8, wherein the protector comprises:
the current detection assembly is electrically connected with the converter body and is used for detecting the current flowing through the converter body;
and the control assembly is respectively in signal connection with the converter body and the current detection assembly and is used for controlling the converter body to stop working when the current flowing through the converter body exceeds a preset threshold value.
10. The direct current system of claim 9, further comprising:
and the central control equipment is in signal connection with the circuit breakers respectively and is used for determining whether the branches have faults or not according to the action states of the circuit breakers and determining the fault branch when the branches have the faults.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010838132.7A CN112003252B (en) | 2020-08-19 | 2020-08-19 | Circuit fault cutting device and direct current system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010838132.7A CN112003252B (en) | 2020-08-19 | 2020-08-19 | Circuit fault cutting device and direct current system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112003252A true CN112003252A (en) | 2020-11-27 |
| CN112003252B CN112003252B (en) | 2023-12-22 |
Family
ID=73472642
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010838132.7A Active CN112003252B (en) | 2020-08-19 | 2020-08-19 | Circuit fault cutting device and direct current system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112003252B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114498578A (en) * | 2021-12-28 | 2022-05-13 | 深圳供电局有限公司 | Direct current power supply and distribution protection method and device, computer equipment and storage medium |
| CN117493497A (en) * | 2023-12-28 | 2024-02-02 | 西安交通工程学院 | Maintenance method and system applied to train equipment |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100128505A1 (en) * | 2008-09-23 | 2010-05-27 | Abb Oy | Current measurement in an inverter unit and a frequency converter |
| CN104065157A (en) * | 2014-06-09 | 2014-09-24 | 深圳微网能源管理系统实验室有限公司 | Uninterruptible power supply with improved power supply reliability |
| CN203859490U (en) * | 2014-03-19 | 2014-10-01 | 湖北省电力勘测设计院 | Circuit for solving protection switch breaking in parallel power supply DC system short circuit |
| WO2015108614A1 (en) * | 2014-01-15 | 2015-07-23 | Abb Technology Ag | Modular, multi-channel, interleaved power converters |
| US20170047727A1 (en) * | 2014-02-27 | 2017-02-16 | Nr Electric Co., Ltd | Direct-current power transmission protection device, converter and protection method |
| CN108879623A (en) * | 2018-06-13 | 2018-11-23 | 南京南瑞继保电气有限公司 | A kind of multi-voltage grade DC grid system and control guard method |
| CN108988454A (en) * | 2018-08-01 | 2018-12-11 | 天津津电供电设计所有限公司 | Energy storage type bus circuit structure and DC power system |
-
2020
- 2020-08-19 CN CN202010838132.7A patent/CN112003252B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100128505A1 (en) * | 2008-09-23 | 2010-05-27 | Abb Oy | Current measurement in an inverter unit and a frequency converter |
| WO2015108614A1 (en) * | 2014-01-15 | 2015-07-23 | Abb Technology Ag | Modular, multi-channel, interleaved power converters |
| US20170047727A1 (en) * | 2014-02-27 | 2017-02-16 | Nr Electric Co., Ltd | Direct-current power transmission protection device, converter and protection method |
| CN203859490U (en) * | 2014-03-19 | 2014-10-01 | 湖北省电力勘测设计院 | Circuit for solving protection switch breaking in parallel power supply DC system short circuit |
| CN104065157A (en) * | 2014-06-09 | 2014-09-24 | 深圳微网能源管理系统实验室有限公司 | Uninterruptible power supply with improved power supply reliability |
| CN108879623A (en) * | 2018-06-13 | 2018-11-23 | 南京南瑞继保电气有限公司 | A kind of multi-voltage grade DC grid system and control guard method |
| CN108988454A (en) * | 2018-08-01 | 2018-12-11 | 天津津电供电设计所有限公司 | Energy storage type bus circuit structure and DC power system |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114498578A (en) * | 2021-12-28 | 2022-05-13 | 深圳供电局有限公司 | Direct current power supply and distribution protection method and device, computer equipment and storage medium |
| CN114498578B (en) * | 2021-12-28 | 2024-03-22 | 深圳供电局有限公司 | DC power supply and distribution protection method and device, computer equipment and storage medium |
| CN117493497A (en) * | 2023-12-28 | 2024-02-02 | 西安交通工程学院 | Maintenance method and system applied to train equipment |
| CN117493497B (en) * | 2023-12-28 | 2024-06-07 | 西安交通工程学院 | Maintenance method and system applied to train equipment |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112003252B (en) | 2023-12-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Salomonsson et al. | Protection of low-voltage DC microgrids | |
| CN103004047B (en) | For distributed power generation power supply provides the system and method for arc fault and/or earth fault protection | |
| Tang et al. | Locating and isolating DC faults in multi-terminal DC systems | |
| CN103081268B (en) | Earthing device | |
| Carminati et al. | Ground fault analysis of low voltage DC micro-grids with active front-end converter | |
| CN112003252B (en) | Circuit fault cutting device and direct current system | |
| CN101944721A (en) | Valve fault detection treatment method of high-voltage direct-current transmission system | |
| CN105656051A (en) | Transient-energy dissipation device | |
| Lazzari et al. | Selectivity and security of DC microgrid under line-to-ground fault | |
| CN111884244A (en) | Method and system for judging phase of alternating current fault on converter transformer valve side | |
| CN109119975A (en) | A kind of failure protection method of the breaker of direct current system and its start-up course | |
| CN110488146A (en) | A kind of DC distribution net type insulation monitoring system and D.C. isolation monitoring device | |
| CN104578170A (en) | High-low-voltage ride-through device of thermal power generating unit auxiliary frequency converter | |
| CN214750546U (en) | Direct-current ground insulation impedance detection circuit for bridge arm topology converter | |
| CN107834554A (en) | Suitable for active and standby access system, the control method and device of voltage source converter | |
| CN117713187A (en) | Inverter and switch detection method | |
| CN111864703B (en) | Device and method for realizing direct-current networking of ship electric propulsion system | |
| CN112491089A (en) | Micro-grid on-grid and off-grid hybrid switching system and method | |
| CN112379171A (en) | Direct-current ground insulation impedance detection circuit and method for bridge arm topology converter | |
| GB2586343A (en) | Power electronic converter with a ground fault detection unit that shares a common ground with both DC ports and AC ports | |
| CN204706895U (en) | Fossil power plant auxiliary engine frequency converter high-low voltage traversing device | |
| CN112290520B (en) | Grounding fault protection method for metal return line of three-terminal direct-current power transmission system | |
| CN114285371A (en) | High-reliability intelligent monitoring communication combiner box and method for photovoltaic power generation system | |
| Parker et al. | DC protection of a multi-terminal HVDC network featuring offshore wind farms | |
| CN110535105B (en) | Direct-current micro-grid fault isolation method based on alternating-current circuit breaker removal |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |