Communication direct-current composite circuit breaking device

Abstract

The invention discloses a communication direct-current composite circuit breaking device, which belongs to the technical field of low-voltage direct-current protection, receives output current of a communication direct-current power supply system through an input module, and performs fault detection on the output current through a composite circuit breaking module. When an alternating-current series-in fault occurs, a fault removal device in the composite circuit breaking module cuts off the series-in alternating current, and when a power-losing fault occurs, a protection device in the composite circuit breaking module generates a reverse power supply current to maintain power supply of the communication direct-current power supply system. Therefore, normal operation of the communication direct-current power supply system is guaranteed at the moment that the storage battery is disconnected when a fault that alternating-current strong current is connected into direct current and an off-line verification test needs to be carried out on the communication direct-current power supply system, normal operation of communication equipment is maintained, and operation stability and safety of the communication equipment are guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of low-voltage direct current protection, and in particular to a communication direct current composite circuit breaker device. Background Art

[0002] The communication DC power supply system in the substation is extremely important, and the battery circuit breaker as a communication DC power supply is even more important. There are two problems with the communication DC circuit breaker in the prior art. One is that when the AC system in the substation is strongly grounded, since the communication DC is also a grounding system, it is easy for the AC to be connected to the DC high voltage to counterattack and damage the communication equipment. If the DC circuit breaker is set to trip, although the fault of the AC strong current being connected to the DC can be cut off, the DC power supply will also be interrupted. Since the continuity of the communication power supply is extremely important and cannot be interrupted, this will lose one thing while focusing on the other, and it is difficult to simultaneously cut off the fault and not interrupt the DC power transmission. Of course, all the circuit breakers in the prior art cannot maintain power supply while cutting off the fault; second, in order to ensure the performance of the communication battery, it must be frequently tested offline. During the test, the battery must be disconnected from the DC bus by the circuit breaker before it can be tested. However, when the AC power failure occurs during the test, the battery will be separated from the DC bus, which will cause a serious accident of a large number of communication equipment shutdowns. Therefore, it is urgent to realize a technology that can immediately return to the normal power supply mode when the bus room power is off during the test.

[0003] Chinese patent, publication number: CN114498585A, publication date: May 13, 2022, discloses a DC circuit breaker disconnection control method and system, by obtaining the current flowing through the main branch of the DC circuit breaker and the DC bus voltage where the DC circuit breaker is located; according to the current and voltage, when it is determined that the DC circuit breaker preparatory control conditions are met, the main branch current is converted to the transfer branch operation; when it is determined that the main branch current is successfully converted to the transfer branch, the main branch mechanical switch is opened; when it is determined that the main branch mechanical switch is successfully opened, it is determined whether the trip signal sent by the DC protection is received before the preset DC protection maximum action time arrives. If the trip signal is received, the transfer branch current is converted to the energy consumption branch operation. If the trip signal is not received, the DC circuit breaker state recovery operation is performed. Although the input signal has a fault detection operation to ensure the normal operation of the system, it is still difficult to solve the problem of ensuring normal power supply of the system when encountering an AC power failure. Summary of the invention

[0004] The present invention aims at the problem that the circuit breaker in the existing communication DC power supply system is difficult to cut off the fault under the premise of ensuring that the normal power supply is not interrupted when encountering an AC power failure fault. A communication DC composite circuit breaker device is provided. The output current of the communication DC power supply system is received through an input module, and the composite circuit breaker module performs fault detection on the output current. When an AC series fault occurs, the fault cutting device in the composite circuit breaker module cuts off the series-in AC power. When a power failure fault occurs, the protection device in the composite circuit breaker module generates a reverse power supply current to maintain the power supply of the communication DC power supply system. Therefore, when a fault of strong AC current being series-into DC is encountered and the communication DC power supply system needs to be offline verified and tested, the normal operation of the communication DC power supply system is guaranteed at the moment when the battery is disconnected, thereby maintaining the normal operation of the communication equipment, and ensuring the operation stability and safety of the communication equipment.

[0005] In a first aspect, a technical solution provided in an embodiment of the present invention is: a communication DC composite circuit breaker device, comprising an input module, a composite circuit breaker module and an output module connected in sequence; the composite circuit breaker module is wrapped by arc extinguishing liquid; The composite circuit breaker module includes a fault removal device and a protection device connected in series; the input module receives the output current of the communication DC power supply system and detects the output current through the fault removal device and the protection device, and outputs the output current through the output module if the detection passes; If there is alternating current in the output current, the fault removal device performs a circuit breaking action to generate an AC arc and a DC arc, and performs a fault removal action by eliminating the AC arc through the arc extinguishing fluid; If the output current is smaller than the set threshold, the protection device generates a reverse supply current to replace the output current to perform a circuit breaker protection action.

[0006] In this scheme, when the output current of the communication DC power supply system is connected to the communication DC composite circuit breaker, if an AC fault current is connected in series, the AC power is amplified by the fault removal device, and the fault removal device is cut to synchronously perform the circuit breaking action. Since the arc extinguishing ability of the circuit breaker of the fault removal device is relatively weak, the AC fault current connected in series can be isolated by arc extinguishing liquid. For the DC current in the output current, since the DC component has no zero crossing point, the circuit breaker of the fault removal device cannot extinguish the DC arc, thereby achieving the purpose of not interrupting the DC power supply while cutting off the AC fault, maintaining the power supply stability of the communication DC power supply system, and ensuring that the communication equipment will not suffer economic losses due to power failure; when it is necessary to perform an offline calibration test on the battery in the communication DC power supply system, the output current will lose power for a very short time, and the protection device will generate an instantaneous reverse power supply current, and the existence time of the reverse power supply current will be greater than the power failure time, overcoming the contradiction that the communication DC system cannot remedy the power supply once the AC power supply is lost during the battery test, thereby greatly improving the reliability and safety of the communication power DC system.

[0007] Preferably, the protection device comprises a first protection mechanism and a second protection mechanism which are arranged in parallel with each other, and the first protection mechanism and the second protection mechanism are in a double series structure.

[0008] In this solution, the first protection mechanism and the second protection mechanism are in a double series structure. If one of the protection mechanisms detects an abnormality and cuts off the current, the entire circuit will be powered off immediately, thereby effectively preventing the fault from expanding or causing more serious safety problems. Redundant protection is provided. Even if one protection mechanism fails or malfunctions, the other protection mechanism can still work normally, ensuring the safety of the circuit and improving the safety of the circuit.

[0009] Preferably, the fault removal device comprises a first removal circuit and a second removal circuit which are connected in parallel with each other, and the first removal circuit and the second removal circuit are in a double series structure with each other.

[0010] In this solution, the first cut-off circuit and the second cut-off circuit are in a double-group series structure. If one of the cut-off circuits detects an abnormality and cuts off the current, the entire circuit will be powered off immediately, thereby effectively preventing the fault from expanding or causing more serious safety problems. Redundant protection is provided. Even if one protection mechanism fails or malfunctions, the other cut-off circuit can still work normally, ensuring that the composite circuit breaker can operate normally and improving the safety of the circuit.

[0011] Preferably, the first protection mechanism includes a first DC circuit breaker disconnecting mechanism, a first bidirectional thyristor and a first varistor; The first end of the first DC circuit breaker disconnecting mechanism is electrically connected to the input module and the negative pole of the first bidirectional thyristor, and the second end of the first DC circuit breaker disconnecting mechanism is electrically connected to the positive pole of the first bidirectional thyristor; the positive pole of the first bidirectional thyristor is electrically connected to the second end of the first varistor, and the negative pole of the first bidirectional thyristor is electrically connected to the first end of the first varistor.

[0012] In this solution, when a power failure occurs, the input voltage is less than 10% of the battery voltage in the communication DC power supply system, which meets the breakdown condition of the first varistor and triggers the first bidirectional thyristor to turn on. In this way, the first bidirectional thyristor short-circuits the break of the first DC circuit breaker breaking mechanism, generating an instantaneous reverse current to power the communication equipment. Since the action time limit of the first varistor and the first thyristor is in microseconds, it is possible to achieve a zero-second delay to return to the battery to power the communication equipment, thereby overcoming the contradiction that once the communication DC power supply system loses the AC power supply when the battery is undergoing an offline verification test, the battery cannot provide power, thereby greatly improving the reliability and safety of the communication DC power supply system.

[0013] Preferably, the second protection mechanism comprises a second DC circuit breaker disconnecting mechanism, a second bidirectional thyristor and a second varistor; The first end of the second DC circuit breaker disconnecting mechanism is electrically connected to the input module and the negative pole of the second bidirectional thyristor, and the second end of the second DC circuit breaker disconnecting mechanism is electrically connected to the positive pole of the second bidirectional thyristor; the positive pole of the second bidirectional thyristor is electrically connected to the second end of the second varistor, and the negative pole of the second bidirectional thyristor is electrically connected to the first end of the second varistor.

[0014] In this scheme, when a power failure occurs and the first protection mechanism cannot operate normally, the second protection mechanism is started to perform a circuit breaker protection action. At this time, the input voltage is less than 10% of the battery voltage in the communication DC power supply system, which meets the breakdown condition of the second varistor and triggers the second bidirectional thyristor to turn on. In this way, the second bidirectional thyristor short-circuits the break of the second DC circuit breaker breaking mechanism, generating an instantaneous reverse current to power the communication equipment. Since the action time limit of the second varistor and the second thyristor is in the microsecond level, it is possible to achieve a zero-second delay to return to the battery to power the communication equipment, overcoming the contradiction that once the communication DC power supply system loses the AC power supply when the battery is undergoing an offline verification test, the battery cannot remedy the power supply, thereby greatly improving the reliability and safety of the communication DC power supply system. At the same time, a first protection mechanism and a second protection mechanism are set in parallel, so that when one of them fails, the other can continue to work normally, greatly ensuring the operating reliability of the communication DC composite circuit breaker device.

[0015] Preferably, the first removal circuit comprises a first contactor, a first fixed capacitor and a first resonant coil; The first end of the first contactor is electrically connected to the first protection mechanism, the second end of the first contactor is electrically connected to the first end of the first fixed capacitor and the first end of the first resonant coil, and the second end of the first fixed capacitor is electrically connected to the second end of the first resonant coil.

[0016] In this solution, when an AC series fault occurs, the AC current resonates and is amplified through the first resonant coil and the first fixed capacitor, causing the first contactor contact to operate to disconnect the circuit. Since the arc extinguishing ability of the contactor is relatively weak, the arc can be extinguished and isolated immediately for the AC fault current component that is series-connected. However, for the DC power supply current, since the DC component has no zero crossing point, the first contactor cannot extinguish the DC arc. Therefore, it is achieved that the DC power supply is not interrupted while the AC series fault is removed, thereby ensuring that the communication equipment can still maintain normal operation when encountering an AC series fault, thereby ensuring the working stability of the communication equipment.

[0017] Preferably, the second removal circuit comprises a second contactor, a second fixed capacitor and a second resonant coil; The first end of the second contactor is electrically connected to the second protection mechanism, the second end of the second contactor is electrically connected to the first end of the second fixed capacitor and the first end of the second resonant coil, and the second end of the second fixed capacitor is electrically connected to the second end of the second resonant coil.

[0018] In this scheme, when an AC series fault occurs and the first cutting circuit cannot work normally, the AC current resonates and amplifies through the second resonant coil and the second fixed capacitor, so that the second contactor contact operates to disconnect the circuit. Since the arc extinguishing ability of the contactor is relatively weak, the arc extinguishing and isolation of the AC fault current component can be immediately achieved. However, for the DC power supply current, since the DC component has no zero crossing point, the second contactor cannot extinguish the DC arc. Therefore, it is achieved that the DC power supply is not interrupted while the AC series fault is cut off, thereby ensuring that the communication equipment can still maintain normal operation when encountering an AC series fault, ensuring the working stability of the communication equipment, and when the first cutting circuit fails, the second cutting circuit performs the fault cutting action, so that when one of them fails, the other can continue to work normally, greatly ensuring the operating reliability of the communication DC composite circuit breaker.

[0019] Preferably, it further comprises an opening and closing handle, wherein the opening and closing handle is connected to operating elements of the first DC circuit breaker disconnecting mechanism and the second DC circuit breaker disconnecting mechanism.

[0020] In this solution, the opening and closing handle acts as a master switch. When the opening and closing handle is disconnected, the communication DC composite circuit breaker device is disconnected, and the communication DC power supply system does not supply power to the communication equipment. When the opening and closing handle is closed, the operating elements of the first DC circuit breaker disconnecting mechanism and the second DC circuit breaker disconnecting mechanism are closed, and the communication DC power supply system supplies power to the communication equipment, so that when the communication DC composite circuit breaker device fails continuously, the circuit can be manually controlled to be on and off, thereby ensuring safe operation of the system.

[0021] Preferably, it further comprises an insulating shell, wherein the composite circuit breaker module is arranged in the insulating shell, the insulating shell has a sealing structure, and the insulating shell is filled with the arc extinguishing liquid.

[0022] In this solution, the insulating shell serves as the outer layer protection of the composite circuit breaker module, and has excellent insulation performance. It can effectively isolate the electrical components from direct contact with the external environment, and prevent leakage and short circuit accidents. The sealing structure of the insulating shell further enhances its protection ability, preventing dust, moisture and other external impurities from entering the shell, thereby keeping the internal environment clean and dry, and ensuring the stable operation of the composite circuit breaker module; arc extinguishing liquid is a liquid medium specially designed to quickly extinguish arcs. When the circuit breaker generates an arc when breaking the circuit, the arc extinguishing liquid can quickly surround and cool the arc, and at the same time cut off the current channel of the arc, thereby effectively extinguishing the arc and reducing the damage of the arc to the circuit breaker and circuit equipment.

[0023] Preferably, the arc extinguishing fluid is carbon tetrachloride arc extinguishing fluid.

[0024] In this scheme, since carbon tetrachloride is a colorless and transparent liquid, its non-conductive property makes it safe to use in electrical fires. During the arc extinguishing process, it will not pass due to current, thus avoiding secondary disasters caused by conductivity. Therefore, carbon tetrachloride is used as the arc extinguishing liquid.

[0025] The beneficial effects of the present invention are as follows: (1) When a power failure occurs in the communication DC power supply system, the input voltage is less than 10% of the battery voltage in the communication DC power supply system, which satisfies the breakdown condition of the varistor and triggers the bidirectional thyristor to conduct. In this way, the bidirectional thyristor short-circuits the break of the first DC circuit breaker breaking mechanism, generating an instantaneous reverse current to power the communication equipment. Since the action time limit of the varistor and the thyristor is in the microsecond level, it is possible to achieve a zero-second delay to return to the battery to power the communication equipment, thus overcoming the contradiction that the battery cannot remedy the power supply once the communication DC power supply system loses the AC power supply when the battery is undergoing an offline verification test, thereby greatly improving the communication equipment. The reliability and safety of the communication DC power supply system are improved; (2) when an AC string fault occurs in the communication DC power supply system, the AC current resonates and amplifies through the resonant coil and the fixed capacitor, so that the contactor contacts are actuated to disconnect the circuit. Since the arc extinguishing capability of the contactor is relatively weak, the AC fault current component can be immediately extinguished and isolated. However, for the DC power supply current, since the DC component has no zero crossing point, the first contactor cannot extinguish the DC arc. Therefore, it is achieved that the DC power supply is not interrupted while the AC string fault is removed, thereby ensuring that the communication equipment can still maintain normal operation when encountering an AC string fault, and ensuring the working stability of the communication equipment; (3) The present invention provides redundant protection by providing a first protection mechanism and a second protection mechanism in a double-group series structure and a first cut-off circuit and a second cut-off circuit in a double-group series structure. Even if one protection mechanism and / or a cut-off circuit fails or malfunctions, the other protection mechanism and / or a cut-off circuit can still operate normally, thereby ensuring the safety of the circuit and improving the safety of the circuit.

[0026] The above invention content is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Other features, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings. The drawings are only for the purpose of illustrating preferred embodiments and are not to be considered as limiting the present invention. Also, the same reference symbols are used throughout the drawings to represent the same parts.

[0028] Figure 1 This is a structural block diagram of a communication DC composite circuit breaker device of the present invention; Figure 2 This is a circuit diagram of a communication DC composite circuit breaker device of the present invention; In the figure: 1-insulating shell; 2-arc extinguishing liquid; 3-input module; 4-output module; 5-opening and closing handle; 6-first DC circuit breaker breaking mechanism; 7-second DC circuit breaker breaking mechanism; 8-first bidirectional thyristor; 9-second bidirectional thyristor; 10-first varistor; 11-second varistor; 12-first contactor; 13-second contactor; 14-first fixed capacitor; 15-second fixed capacitor; 16-first resonant coil; 17-second resonant coil. DETAILED DESCRIPTION

[0029] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific implementation method described herein is only an optimal embodiment of the present invention, which is only used to explain the present invention and does not limit the scope of protection of the present invention. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0030] Before discussing the exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processes or methods depicted as flow charts. Although the flow charts describe the operations (or steps) as sequential processes, many of the operations (or steps) therein can be implemented in parallel, concurrently, or simultaneously. In addition, the order of the operations can be rearranged. The process can be terminated when its operation is completed, but can also have additional steps not included in the drawings; the process can correspond to a method, function, procedure, subroutine, subprogram, etc.

[0031] Example: Figure 1 As shown, in order to solve the problem that the circuit breaker in the existing communication DC power supply system is difficult to cut off the fault under the premise of ensuring that the normal power supply is not interrupted when encountering an AC power failure, this embodiment provides a communication DC composite circuit breaker device, including an input module 3, a composite circuit breaker module and an output module 4 connected in sequence; the composite circuit breaker module is wrapped by an arc extinguishing liquid 2; The composite circuit breaker module includes a fault removal device and a protection device connected in series; the input module 3 receives the output current of the communication DC power supply system and detects the output current through the fault removal device and the protection device, and outputs the output current through the output module 4 if the detection passes; If there is alternating current in the output current, the fault removal device performs a circuit breaking action to generate an AC arc and a DC arc, and eliminates the AC arc through the arc extinguishing fluid 2 to perform a fault removal action; If the output current is smaller than the set threshold, the protection device generates a reverse supply current to replace the output current to perform a circuit breaker protection action.

[0032] In this embodiment, when the output current of the communication DC power supply system is connected to the communication DC composite circuit breaker, if an AC fault current is connected in series, the AC power is amplified by the fault removal device, and the fault removal device is cut to synchronously perform the circuit breaking action. Since the arc extinguishing ability of the circuit breaker point of the fault removal device is relatively weak, the connected AC fault current can be arc extinguished and isolated by the arc extinguishing liquid 2. For the DC current in the output current, since the DC component has no zero crossing point, the circuit breaker point of the fault removal device cannot extinguish the DC arc, thereby achieving the uninterrupted DC power supply while cutting off the AC fault, maintaining the power supply stability of the communication DC power supply system, and ensuring that the communication equipment will not suffer economic losses due to power failure; when it is necessary to perform an offline calibration test on the battery in the communication DC power supply system, the output current will have a very short power failure, and the protection device will generate an instantaneous reverse power supply current, and the existence time of the reverse power supply current will be greater than the power failure time, which overcomes the contradiction that the communication DC system cannot remedy the power supply once the AC power supply is lost during the battery test, thereby greatly improving the reliability and safety of the communication power DC system.

[0033] In this embodiment, the protection device includes a first protection mechanism and a second protection mechanism which are arranged in parallel with each other, and the first protection mechanism and the second protection mechanism are in a double series structure.

[0034] In this embodiment, the first protection mechanism and the second protection mechanism are in a double series structure. If one of the protection mechanisms detects an abnormality and cuts off the current, the entire circuit will be powered off immediately, thereby effectively preventing the fault from expanding or causing more serious safety problems. Redundant protection is provided. Even if one protection mechanism fails or malfunctions, the other protection mechanism can still work normally, ensuring the safety of the circuit and improving the safety of the circuit.

[0035] In this embodiment, the fault removal device includes a first removal circuit and a second removal circuit which are connected in parallel to each other, and the first removal circuit and the second removal circuit are in a double series structure.

[0036] In this embodiment, the first cut-off circuit and the second cut-off circuit are in a double-group series structure. If one of the cut-off circuits detects an abnormality and cuts off the current, the entire circuit will be powered off immediately, thereby effectively preventing the fault from expanding or causing more serious safety problems. Redundant protection is provided. Even if one protection mechanism fails or malfunctions, the other cut-off circuit can still work normally, ensuring that the composite circuit breaker device can operate normally and improving the safety of the circuit.

[0037] In this embodiment, Figure 2 As shown, the first protection mechanism includes a first DC circuit breaker disconnecting mechanism 6, a first bidirectional thyristor 8 and a first varistor 10; The first end of the first DC circuit breaker disconnecting mechanism 6 is electrically connected to the input module 3 and the negative pole of the first bidirectional thyristor 8, and the second end of the first DC circuit breaker disconnecting mechanism 6 is electrically connected to the positive pole of the first bidirectional thyristor 8; the positive pole of the first bidirectional thyristor 8 is electrically connected to the second end of the first varistor 10, and the negative pole of the first bidirectional thyristor 8 is electrically connected to the first end of the first varistor 10.

[0038] In this embodiment, when a power failure occurs, the input voltage is less than 10% of the battery voltage in the communication DC power supply system, which meets the breakdown condition of the first varistor 10 and triggers the first bidirectional thyristor 8 to turn on. In this way, the first bidirectional thyristor short-circuits the break of the first DC circuit breaker disconnecting mechanism 6, generating an instantaneous reverse current to power the communication equipment. Since the action time limit of the first varistor 10 and the first thyristor is in microseconds, it is possible to achieve a zero-second delay to return to the battery to power the communication equipment, thereby overcoming the contradiction that once the communication DC power supply system loses the AC power supply when the battery is undergoing an offline verification test, the battery cannot provide power, thereby greatly improving the reliability and safety of the communication DC power supply system.

[0039] In this embodiment, the second protection mechanism includes a second DC circuit breaker disconnecting mechanism 7, a second bidirectional thyristor 9 and a second varistor 11; The first end of the second DC circuit breaker disconnecting mechanism 7 is electrically connected to the input module 3 and the negative pole of the second bidirectional thyristor 9, and the second end of the second DC circuit breaker disconnecting mechanism 7 is electrically connected to the positive pole of the second bidirectional thyristor 9; the positive pole of the second bidirectional thyristor 9 is electrically connected to the second end of the second varistor 11, and the negative pole of the second bidirectional thyristor 9 is electrically connected to the first end of the second varistor 11.

[0040] In this embodiment, when a power failure occurs and the first protection mechanism cannot operate normally, the second protection mechanism is started to perform a circuit breaker protection action. At this time, the input voltage is less than 10% of the battery voltage in the communication DC power supply system, which meets the breakdown condition of the second varistor 11 and triggers the second bidirectional thyristor 9 to turn on. In this way, the second bidirectional thyristor short-circuits the break of the second DC circuit breaker disconnecting mechanism 7, generating an instantaneous reverse current to power the communication equipment. Since the action time limit of the second varistor 11 and the second thyristor is in the microsecond level, it is possible to achieve a zero-second delay to return to the battery to power the communication equipment, thereby overcoming the contradiction that once the communication DC power supply system loses the AC power supply when the battery is undergoing an offline verification test, the battery cannot provide power, thereby greatly improving the reliability and safety of the communication DC power supply system. At the same time, a first protection mechanism and a second protection mechanism are arranged in parallel, so that when one of them fails, the other can continue to operate normally, thereby greatly ensuring the operating reliability of the communication DC composite circuit breaker device.

[0041] In this embodiment, Figure 2 As shown, the first removal circuit includes a first contactor 12, a first fixed capacitor 14 and a first resonant coil 16; The first end of the first contactor 12 is electrically connected to the first protection mechanism, the second end of the first contactor 12 is electrically connected to the first end of the first fixed capacitor 14 and the first end of the first resonant coil 16 , and the second end of the first fixed capacitor 14 is electrically connected to the second end of the first resonant coil 16 .

[0042] In this embodiment, when an AC series fault occurs, the AC current resonates and is amplified through the first resonant coil 16 and the first fixed capacitor 14, so that the contact of the first contactor 12 is actuated to disconnect the circuit. Since the arc extinguishing ability of the contactor is relatively weak, the arc extinguishing and isolation of the AC fault current component can be immediately achieved. However, for the DC power supply current, since the DC component has no zero crossing point, the first contactor 12 cannot extinguish the DC arc. Therefore, it is achieved that the DC power supply is not interrupted while the AC series fault is removed, thereby ensuring that the communication equipment can still maintain normal operation when encountering an AC series fault, thereby ensuring the working stability of the communication equipment.

[0043] In this embodiment, the second removal circuit includes a second contactor 13, a second fixed capacitor 15 and a second resonant coil 17; The first end of the second contactor 13 is electrically connected to the second protection mechanism, the second end of the second contactor 13 is electrically connected to the first end of the second fixed capacitor 15 and the first end of the second resonant coil 17 , and the second end of the second fixed capacitor 15 is electrically connected to the second end of the second resonant coil 17 .

[0044] In this embodiment, when an AC series fault occurs and the first removal circuit cannot work normally, the AC current resonates and is amplified through the second resonant coil 17 and the second fixed capacitor 15, so that the contact of the second contactor 13 is actuated to disconnect the circuit. Since the arc extinguishing ability of the contactor is relatively weak, the series-in AC fault current component can be immediately arc-extinguished and isolated, but for the DC power supply current, since the DC component has no zero crossing point, the second contactor 13 cannot extinguish the DC arc. Therefore, it is achieved that the DC power supply is not interrupted while the AC series fault is removed, thereby ensuring that the communication equipment can still maintain normal operation when encountering an AC series fault, ensuring the working stability of the communication equipment, and when the first removal circuit fails, the second removal circuit performs the fault removal action, so that when one of them fails, the other can continue to work normally, greatly ensuring the operating reliability of the communication DC composite circuit breaker.

[0045] In this embodiment, the communication DC composite circuit breaker device further includes an opening and closing handle 5 , which is connected to operating elements of the first DC circuit breaker disconnecting mechanism 6 and the second DC circuit breaker disconnecting mechanism 7 .

[0046] In this embodiment, the opening and closing handle 5 acts as a main switch. When the opening and closing handle 5 is disconnected, the communication DC composite circuit breaker device is disconnected, and the communication DC power supply system does not supply power to the communication equipment. When the opening and closing handle 5 is closed, the operating elements of the first DC circuit breaker disconnecting mechanism 6 and the second DC circuit breaker disconnecting mechanism 7 are closed, and the communication DC power supply system supplies power to the communication equipment, so that when the communication DC composite circuit breaker device fails continuously, the circuit can be manually controlled to be on and off, thereby ensuring safe operation of the system.

[0047] In this embodiment, the communication DC composite circuit breaker device further includes an insulating shell 1, the composite circuit breaker module is arranged in the insulating shell 1, the insulating shell 1 has a sealing structure, and the insulating shell 1 is filled with the arc extinguishing liquid 2.

[0048] The insulating housing 1 of this embodiment serves as the outer layer protection of the composite circuit breaker module, has excellent insulation performance, can effectively isolate the electrical components from direct contact with the external environment, and prevent leakage and short circuit accidents. The sealing structure of the insulating housing 1 further enhances its protection ability, preventing dust, moisture and other external impurities from entering the interior of the housing, thereby keeping the internal environment clean and dry, and ensuring the stable operation of the composite circuit breaker module; the arc extinguishing liquid 2 is a liquid medium specially designed for quickly extinguishing the arc. When the circuit breaker generates an arc when breaking the circuit, the arc extinguishing liquid 2 can quickly surround and cool the arc, and at the same time cut off the current path of the arc, thereby effectively extinguishing the arc and reducing the damage of the arc to the circuit breaker and circuit equipment.

[0049] In this embodiment, the type of the arc extinguishing fluid 2 is carbon tetrachloride arc extinguishing fluid 2.

[0050] In this embodiment, carbon tetrachloride is a colorless transparent liquid. Its non-conductive property enables it to be safely used in electrical fires. During the arc extinguishing process, it will not pass due to current, thereby avoiding secondary disasters caused by conductivity. Therefore, carbon tetrachloride is used as the arc extinguishing liquid 2.

[0051] It can be seen from the above embodiments that at least the following substantial effects are achieved: (1) When a power failure occurs in the communication DC power supply system of the present invention, the input voltage is less than 10% of the battery voltage in the communication DC power supply system, which satisfies the breakdown condition of the varistor and triggers the bidirectional thyristor to conduct. In this way, the bidirectional thyristor short-circuits the break of the first DC circuit breaker disconnecting mechanism 6, generating an instantaneous reverse current to power the communication equipment. Since the action time limit of the varistor and the thyristor is in the microsecond level, it is possible to achieve a zero-second delay to return to the battery to power the communication equipment, thus overcoming the contradiction that the communication DC power supply system cannot remedy the power supply once the AC power supply is lost when the battery is undergoing an offline verification test, thereby greatly improving the reliability and safety of the communication DC power supply system; (2) In the present invention, when an AC string-in fault occurs in the communication DC power supply system, the AC current resonates and is amplified through the resonant coil and the fixed capacitor, so that the contactor contacts are actuated to disconnect the circuit. Since the arc extinguishing capability of the contactor is relatively weak, the AC fault current component that is string-in can be immediately extinguished and isolated. However, for the DC power supply current, since the DC component has no zero crossing point, the first contactor 12 cannot extinguish the DC arc. Therefore, it is achieved that the DC power supply is not interrupted while the AC string-in fault is removed, thereby ensuring that the communication equipment can still maintain normal operation when encountering an AC string-in fault, thereby ensuring the working stability of the communication equipment; (3) The present invention provides redundant protection by providing a first protection mechanism and a second protection mechanism in a double-group series structure and a first cut-off circuit and a second cut-off circuit in a double-group series structure. Even if one protection mechanism and / or a cut-off circuit fails or malfunctions, the other protection mechanism and / or a cut-off circuit can still operate normally, thereby ensuring the safety of the circuit and improving the safety of the circuit.

[0052] The specific implementation described above is a preferred implementation of a communication DC composite circuit breaker device of the present invention, and is not intended to limit the specific implementation scope of the present invention. The scope of the present invention includes but is not limited to this specific implementation. All equivalent changes made in accordance with the shape and structure of the present invention are within the protection scope of the present invention.

Claims

1. A communication DC composite circuit breaker device, suitable for a communication DC power supply system, wherein the communication DC power supply system is used to supply power to communication equipment, characterized in that: It includes an input module, a composite circuit breaker module and an output module connected in sequence; the composite circuit breaker module is wrapped by arc extinguishing liquid; The composite circuit breaker module includes a fault removal device and a protection device connected in series; the input module receives the output current of the communication DC power supply system and detects the output current through the fault removal device and the protection device, and outputs the output current through the output module if the detection passes; If there is alternating current in the output current, the fault removal device performs a circuit breaking action to generate an AC arc and a DC arc, and performs a fault removal action by eliminating the AC arc through the arc extinguishing fluid; If the output current is smaller than the set threshold, the protection device generates a reverse supply current to replace the output current to perform a circuit breaker protection action.

2. A communication DC composite circuit breaker device according to claim 1, characterized in that: The protection device comprises a first protection mechanism and a second protection mechanism which are arranged in parallel with each other, and the first protection mechanism and the second protection mechanism are in a double series structure.

3. A communication DC composite circuit breaker device according to claim 1, characterized in that: The fault removal device comprises a first removal circuit and a second removal circuit which are connected in parallel with each other, and the first removal circuit and the second removal circuit are in a double series structure.

4. A communication DC composite circuit breaker device according to claim 2, characterized in that: The first protection mechanism includes a first DC circuit breaker disconnecting mechanism, a first bidirectional thyristor and a first varistor; The first end of the first DC circuit breaker disconnecting mechanism is electrically connected to the input module and the negative pole of the first bidirectional thyristor, and the second end of the first DC circuit breaker disconnecting mechanism is electrically connected to the positive pole of the first bidirectional thyristor; the positive pole of the first bidirectional thyristor is electrically connected to the second end of the first varistor, and the negative pole of the first bidirectional thyristor is electrically connected to the first end of the first varistor.

5. A communication DC composite circuit breaker device according to claim 2, characterized in that: The second protection mechanism includes a second DC circuit breaker disconnecting mechanism, a second bidirectional thyristor and a second varistor; The first end of the second DC circuit breaker disconnecting mechanism is electrically connected to the input module and the negative pole of the second bidirectional thyristor, and the second end of the second DC circuit breaker disconnecting mechanism is electrically connected to the positive pole of the second bidirectional thyristor; the positive pole of the second bidirectional thyristor is electrically connected to the second end of the second varistor, and the negative pole of the second bidirectional thyristor is electrically connected to the first end of the second varistor.

6. A communication DC composite circuit breaker device according to claim 3, characterized in that: The first removal circuit includes a first contactor, a first fixed capacitor and a first resonant coil; The first end of the first contactor is electrically connected to the first protection mechanism, the second end of the first contactor is electrically connected to the first end of the first fixed capacitor and the first end of the first resonant coil, and the second end of the first fixed capacitor is electrically connected to the second end of the first resonant coil.

7. A communication DC composite circuit breaker device according to claim 3, characterized in that: The second removal circuit includes a second contactor, a second fixed capacitor and a second resonant coil; The first end of the second contactor is electrically connected to the second protection mechanism, the second end of the second contactor is electrically connected to the first end of the second fixed capacitor and the first end of the second resonant coil, and the second end of the second fixed capacitor is electrically connected to the second end of the second resonant coil.

8. A communication DC composite circuit breaker device according to claim 1, characterized in that: It also includes an opening and closing handle, which is connected to the operating elements of the first DC circuit breaker disconnecting mechanism and the second DC circuit breaker disconnecting mechanism.

9. A communication DC composite circuit breaker device according to claim 1, characterized in that: It also includes an insulating shell, the composite circuit breaker module is arranged in the insulating shell, the insulating shell has a sealing structure, and the insulating shell is filled with the arc extinguishing liquid.

10. A communication DC composite circuit breaker device according to claim 1 or 8, characterized in that: The type of arc extinguishing liquid is carbon tetrachloride arc extinguishing liquid.

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