DC circuit breaker and control method thereof
By integrating a reverse connection detection unit, a control unit, and a locking execution unit into a DC circuit breaker, automatic detection and mechanical locking of the DC power supply polarity are achieved. This solves the problem that DC circuit breakers cannot identify reverse connections, avoids equipment damage and safety accidents caused by reverse polarity, and improves the safety and fault tolerance of the system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-02-06
- Publication Date
- 2026-03-27
AI Technical Summary
Existing DC circuit breakers cannot promptly identify and prevent maloperation caused by reverse connection of DC power supply, resulting in serious safety hazards such as protection function failure, arc burning, contact welding, and fire.
The system employs a combination of a reverse connection detection unit, a control unit, and a locking execution unit. By detecting the voltage polarity, a reverse connection signal is generated, which controls the locking execution unit to be in the locking position, mechanically locking the mechanical closing and opening mechanism to prevent closing operations.
It enables proactive identification and forced prevention of reverse connection of DC circuit breakers, avoiding equipment damage and personal safety accidents caused by reverse polarity connection, and improving the fault tolerance and safety of the system.
Smart Images
Figure CN121749079A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of power electronics, in particular to a direct current circuit breaker and a control method thereof. BACKGROUND
[0002] In a direct current power distribution system, the direct current circuit breaker as a core protection device undertakes the important function of rapidly cutting off the main loop current under overload, short circuit and other fault conditions, which is directly related to the safe and stable operation of the entire system. However, in the construction and operation process of the direct current power distribution system, due to unclear terminal identification, misjudgment of polarity by the operator or complex operation environment and other factors, the problem of reverse connection of the positive and negative poles of the direct current power supply is prone to occur. When the polarity of the incoming line end or the outgoing line end of the direct current circuit breaker is reversed, the internal electronic control module may fail due to abnormal power supply, and more seriously, the protection mechanism of the circuit breaker itself may be damaged.
[0003] In the related art, for the reverse connection problem of the direct current circuit breaker, a mechanical error prevention structure is usually used, such as asymmetric terminal, special-shaped plug / socket and the like, to forcibly distinguish the positive and negative pole ports, thereby reducing the probability of misconnection in the initial connection stage.
[0004] However, the above protection method is only limited to "preventing initial misconnection", and once the device has been incorrectly connected and put into use, the existing reverse connection state cannot be identified. SUMMARY
[0005] The present application aims to solve the problem that the existing direct current circuit breaker cannot timely identify and prevent misoperation.
[0006] To achieve the above-mentioned purpose, the technical solutions adopted by the embodiments of the present application are as follows: In a first aspect, the embodiments of the present application provide a direct current circuit breaker, which comprises a reverse connection detection unit, a control unit, a locking execution unit and a mechanical combination and separation mechanism. The input end of the reverse connection detection unit is connected to the incoming line end and / or the outgoing line end of the direct current circuit breaker. The output end of the reverse connection detection unit is connected to the input end of the control unit, and the output end of the control unit is connected to the input end of the locking execution unit. The two ends of the mechanical combination and separation mechanism are connected to the main loop respectively. The reverse connection detection unit is configured to detect whether the direct current circuit breaker is in a reverse connection state, and if so, generate and output a reverse connection signal, and transmit the reverse connection signal to the control unit. The control unit is configured to control the locking execution unit to be in a locking position according to the reverse connection signal, to mechanically lock the mechanical opening and closing mechanism, so that the mechanical opening and closing mechanism cannot be connected to the main circuit.
[0007] Optionally, the mechanical opening and closing mechanism comprises an operating member and a contact unit, the contact unit comprising a moving contact, a static contact and a connecting member arranged on the moving contact. When the locking execution unit is in the locking position, the operating member cannot push the connecting member, so that the moving contact and the static contact remain in an open position.
[0008] Optionally, when the locking execution unit is in a reset position, the operating member can mechanically push the connecting member, so that the moving contact and the static contact are in a closed position.
[0009] Optionally, the reverse connection detection unit comprises a voltage detection module. The detection of whether the DC circuit breaker is in a reverse connection state comprises: acquiring a power supply voltage of the DC circuit breaker and a pre-set voltage threshold value; determining whether the DC circuit breaker is in a reverse connection state according to a comparison result of the power supply voltage of the DC circuit breaker and the voltage threshold value.
[0010] Optionally, the reverse connection detection unit comprises an optical coupling detection module. The detection of whether the DC circuit breaker is in a reverse connection state comprises: acquiring an on-off state of an optical coupling device in the optical coupling detection module; determining whether the DC circuit breaker is in a reverse connection state according to the on-off state of the optical coupling device.
[0011] Optionally, the reverse connection detection unit is further configured to generate and output a normal connection signal if it is detected that the DC circuit breaker returns to a normal connection state, and transmit the normal connection signal to the control unit. The control unit is further configured to control the locking execution unit to be in a reset position according to the normal connection signal, to release the mechanical locking of the mechanical opening and closing mechanism, so that the mechanical opening and closing mechanism can be mechanically connected to the main circuit.
[0012] Optionally, the DC circuit breaker further comprises a power supply unit. An input end of the power supply unit is configured to be connected to a line-in end, a line-out end or an external auxiliary power supply of the DC circuit breaker. Output ends of the power supply unit are respectively electrically connected to the reverse connection detection unit, the control unit and the locking execution unit. The power supply unit is configured to obtain an electrical energy signal from the incoming line end, the outgoing line end or an external auxiliary power supply of the DC circuit breaker, and transmit the electrical energy signal to the reverse connection detection unit, the control unit and the locking execution unit, so as to provide electrical energy for the reverse connection detection unit, the control unit and the locking execution unit.
[0013] Optionally, the power supply unit comprises a rectification unit and a power supply circuit. The input end of the rectification unit is connected to the incoming line end, the outgoing line end or the external auxiliary power supply of the DC circuit breaker, the output end of the rectification unit is connected to the input end of the power supply circuit, and the output end of the power supply circuit is electrically connected to the reverse connection detection unit, the control unit and the locking execution unit, respectively. The rectification unit is configured to rectify the DC power supply or the external auxiliary power supply connected thereto, generate a rectified voltage signal, and output the rectified voltage signal to the power supply circuit. The power supply circuit is configured to output the rectified voltage signal to the reverse connection detection unit, the control unit and the locking execution unit.
[0014] Optionally, the locking execution unit comprises an electric drive unit and a mechanical unit. The electric drive unit is mechanically connected to the mechanical unit. The electric drive unit is configured to drive the mechanical unit to move between the locking position and the reset position.
[0015] In a second aspect, the embodiments of the present application further provide a control method of a DC circuit breaker, which is applied to the reverse connection detection unit of the DC circuit breaker, and the method comprises the following steps: detecting whether the DC circuit breaker is in a reverse connection state; If yes, a reverse connection signal is generated and output, and the reverse connection signal is transmitted to the control unit, so that the control unit controls the locking execution unit to be in the locking position according to the reverse connection signal, and mechanically locks the mechanical combination and split mechanism, so that the mechanical combination and split mechanism cannot manually push the operating member to connect the main loop.
[0016] The present application has the following advantages: The application provides a direct current circuit breaker and a control method thereof. When user wiring is completed, a reverse connection detection unit automatically detects the voltage polarity between an incoming line end and / or an outgoing line end, and determines whether a direct current power supply is reversely connected based on the voltage polarity. If yes, a reverse connection signal is generated. The reverse connection signal is transmitted to a control unit. The control unit starts a protection mechanism immediately after receiving the reverse connection signal, that is, controls a locking execution unit to be in a locking position to mechanically lock a mechanical closing and opening mechanism, that is, limits the action freedom degree of the mechanical closing and opening mechanism, so that an operator cannot perform a closing operation on the mechanical closing and opening mechanism, and the mechanical closing and opening mechanism cannot be connected to a main loop, thereby avoiding reverse connection and closing risks from the source. Therefore, the direct current circuit breaker provided by the application can actively find reverse connection and forcibly prevent closing or immediately open the circuit under the reverse connection state, forms an intelligent safety closed loop of "reverse connection and locking", converts the risk of human error operation into automatic and forced intervention of the system, effectively avoids major equipment damage and personal safety accidents caused by polarity reverse connection, and improves the fault tolerance and safety of the system. BRIEF DESCRIPTION OF DRAWINGS
[0017] In order to more clearly illustrate the technical solutions of the embodiments of the application, the drawings needed in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some of the embodiments of the application, and therefore should not be considered as limiting the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.
[0018] Figure 1 A structural schematic diagram of a direct current circuit breaker provided by the embodiments of the application is shown in the figure. Figure 2 A structural schematic diagram of another direct current circuit breaker provided by the embodiments of the application is shown in the figure. Figure 3 A structural schematic diagram of a reverse connection detection unit in a direct current circuit breaker provided by the embodiments of the application is shown in the figure. Figure 4 A structural schematic diagram of another direct current circuit breaker provided by the embodiments of the application is shown in the figure. Figure 5 A structural schematic diagram of a power supply unit in a direct current circuit breaker provided by the embodiments of the application is shown in the figure. Figure 6 A structural schematic diagram of another power supply unit in a direct current circuit breaker provided by the embodiments of the application is shown in the figure. Figure 7 A structural schematic diagram of another power supply unit in a direct current circuit breaker provided by the embodiments of the application is shown in the figure. Figure 8 A flowchart of a control method of a direct current circuit breaker provided by the embodiments of the application is shown in the figure.
[0019] Icon: 100 - DC circuit breaker; 1 - reverse connection detection unit; 2 - control unit; 3 - locking execution unit; 4 - mechanical combination and separation mechanism; 41 - operating member; 42 - contact unit; 6 - power supply unit; 61 - rectifier unit; 62 - power supply circuit. DETAILED DESCRIPTION
[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the accompanying drawings in the embodiments of the present application. It should be understood that the accompanying drawings in the present application only serve the purpose of illustration and description, and are not used to limit the protection scope of the present application. In addition, it should be understood that the schematic drawings are not drawn according to the actual proportions. The flowchart used in the present application shows the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowchart can not be implemented in sequence, and the steps without logical context relationship can be reversed in sequence or implemented simultaneously. In addition, one or more other operations can be added to the flowchart or one or more operations can be removed from the flowchart under the guidance of the content of the present application.
[0021] In addition, the described embodiments are only some of the embodiments of the present application, not all the embodiments. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.
[0022] It should be noted that the term "comprising" will be used in the embodiments of the present application to indicate the presence of the features declared thereafter, but does not exclude the addition of other features.
[0023] Firstly, the professional terms involved in the present application are introduced.
[0024] 1. DC circuit breaker refers to a switching device used to cut off or connect a DC circuit, commonly used in new energy systems (such as photovoltaic, energy storage, electric vehicles).
[0025] 2. Reverse connection state refers to the positive and negative poles of the power supply being connected in reverse, for example, under normal circumstances, the positive pole is connected to the incoming line end A1 and the negative pole is connected to the incoming line end A2, but due to improper operation of the operator, the positive and negative poles of the power supply are connected in reverse, which may cause short circuit, equipment burning, and other serious consequences.
[0026] 3. Reverse connection signal is an electrical signal or digital signal generated by the reverse connection detection unit, indicating that "the polarity reverse connection has been detected".
[0027] 4. Mechanical closing and opening mechanism, which is a mechanical structure (such as a contact operating mechanism) for controlling the on-off of the main circuit, and can realize "closing" (conducting) and "opening" (disconnecting).
[0028] Secondly, the background technology related to the present application is introduced.
[0029] In related technologies, for the reverse connection problem of the DC circuit breaker, the existing countermeasures have obvious deficiencies, as follows: First, most DC circuit breakers focus on arc breaking optimization after fault occurs, and lack of proactive detection of reverse connection risk; Second, some DC circuit breakers propose to use mechanical error prevention structures (such as asymmetric wiring terminals and special-shaped plugs / jacks) to constrain the wiring of the circuit breaker, which can only play a limited role in the initial wiring link and cannot identify the completed reverse connection state; Third, the existing circuit breaker lacks closing forced locking protection, and the operator may forcibly close the circuit breaker without realizing the reverse connection, which may cause arc burning, contact welding and other risks due to abnormal polarity at the moment of closing, and even cause fire and system collapse.
[0030] Therefore, the existing circuit breaker lacks active detection and forced protection mechanism for positive and negative polarity reverse connection state, which leads to the inability to identify and prevent misoperation in time when the polarity is reversed due to miswiring during construction, operation or repair, resulting in failure of protection function, arc burning, contact welding, fire and even system collapse, etc. serious safety hazards.
[0031] To solve the above problems, the present application provides a DC circuit breaker that can actively detect reverse connection and forcibly prevent closing or immediately open the lock in a reverse connection state. By integrating positive and negative polarity detection and electromechanical linkage locking mechanism, an intelligent safety closed loop of "reverse connection and lock" is formed, which converts the risk of human error into automatic forced intervention of the system, effectively avoids major equipment damage and personal safety accidents caused by polarity reverse connection, and improves the fault tolerance and safety of the system.
[0032] The specific structure of the DC circuit breaker provided by the present application and its beneficial effects will be specifically explained through the following embodiments.
[0033] Figure 1 The structure diagram of the DC circuit breaker 100 provided by the present application is shown in Figure 1. Figure 1 As shown in Figure 1, the DC circuit breaker 100 includes a reverse connection detection unit 1, a control unit 2, a locking execution unit 3 and a mechanical closing and opening mechanism 4. The input end of the reverse connection detection unit 1 is connected to the incoming line end and / or the outgoing line end of the DC circuit breaker 100; wherein the incoming line end is used to access the DC power supply, and the outgoing line end is used to connect with the load.
[0034] The output end of the reverse connection detection unit 1 is connected with the input end of the control unit 2, and the output end of the control unit 2 is connected with the input end of the locking execution unit 3. The two ends of the mechanical closing and opening mechanism 4 are connected with the main circuit respectively, wherein the mechanical closing and opening mechanism 4 comprises a closing position and an opening position, when the mechanical closing and opening mechanism 4 is located at the closing position, the main circuit current can be mechanically turned on through the mechanical closing and opening mechanism 4, and when the mechanical closing and opening mechanism 4 is located at the opening position, the main circuit current can be mechanically turned off through the mechanical closing and opening mechanism 4.
[0035] The reverse connection detection unit 1 is used for detecting whether the DC circuit breaker 100 is in a reverse connection state, if yes, a reverse connection signal is generated and output, and the reverse connection signal is transmitted to the control unit 2; in the embodiment, after the user wiring is completed, the voltage polarity between the incoming line end and / or the outgoing line end can be automatically detected through the reverse connection detection unit 1, and whether the DC power supply is “reversely connected” is identified based on the voltage polarity, that is, the positive and negative poles are connected reversely, when it is identified that the positive and negative poles are connected reversely, the reverse connection signal is generated.
[0036] It should be noted that if the reverse connection detection unit 1 detects that the positive and negative poles are connected correctly, it is determined that the DC power supply is not “reversely connected”, that is, no operation is triggered.
[0037] The control unit 2 is used for controlling the locking execution unit 3 to be in a locking position according to the reverse connection signal, so as to mechanically lock the mechanical closing and opening mechanism 4, so that the mechanical closing and opening mechanism 4 cannot turn on the main circuit.
[0038] The locking execution unit 3 is a movable electromechanical execution component, which has two determined stable positions, that is, a locking position and a reset position, and directly intervenes the action freedom of the mechanical closing and opening mechanism 4 through a physical interference mode.
[0039] Exemplarily, the locking execution unit 3 can be an electromagnet, a motor or other actuators. When the locking execution unit 3 is switched to the locking position, the action freedom of the mechanical closing and opening mechanism 4 is physically blocked through the mechanical interference mode by the locking execution unit 3, so that the mechanical closing and opening mechanism 4 cannot complete the “closing” operation, that is, the main circuit is forced to be turned off; when the locking execution unit 3 is switched to the reset position, the locking execution unit 3 does not contact any moving part in the mechanical closing and opening mechanism 4, the mechanical constraint of the mechanical closing and opening mechanism 4 is released, and the operator is allowed to manually or automatically drive the mechanical closing and opening mechanism 4 to complete the closing operation, so as to turn on the main circuit.
[0040] In an implementable manner, when the DC circuit breaker 100 is in the open state and the control unit 2 receives the reverse connection signal, the protection mechanism is started immediately, and a "locking instruction" is sent to the locking execution unit 3. The locking execution unit 3 switches to the locking position in response to the "locking instruction", and mechanically locks the mechanical closing and opening mechanism 4, that is, limits the freedom of the mechanical closing and opening mechanism 4, so that the operator cannot perform the "closing" operation on the mechanical closing and opening mechanism 4, and the mechanical closing and opening mechanism 4 cannot be connected to the main circuit, thereby avoiding the risk of reverse connection closing from the source.
[0041] In another implementable manner, when the DC circuit breaker 100 is in the closed state and the control unit 2 receives the reverse connection signal, the control unit 2 first controls the mechanical closing and opening mechanism 4 to perform the opening action, quickly cuts off the main circuit current, and eliminates the operation risk in the current reverse connection state; and after the opening action is completed, the locking execution unit 3 is immediately controlled to remain in the locking position, preventing the operator from mis-closing, and actively identifying and intervening in the reverse connection risk from the source.
[0042] Therefore, the DC circuit breaker 100 provided in the application can prevent mis-closing operation by detecting and then mechanically locking, and forcibly lock when reverse connection is detected. For reverse connection in the closed state, the circuit breaker is first opened and then locked, and the risk source is completely cut off, effectively avoiding serious consequences such as arc burning, contact welding, fire, and system collapse, and improving the system safety.
[0043] Optionally, the application provides an application scenario of the DC circuit breaker 100 with reverse connection prevention, including a photovoltaic power generation system, an energy storage power station, an electric vehicle charging pile, and rail transit. In the photovoltaic power generation system, the DC circuit breaker 100 can prevent the burning of an inverter due to the reverse connection of a component string, and effectively prevents and controls the reverse connection risk of the DC circuit breaker 100.
[0044] In summary, the embodiment of the present application provides a DC circuit breaker. When the user completes the wiring, the reverse connection detection unit automatically detects the voltage polarity between the incoming line end and / or the outgoing line end, and determines whether the DC power supply is "reversely connected" based on the voltage polarity. If so, a reverse connection signal is generated. The reverse connection signal is transmitted to the control unit. The control unit immediately starts the protection mechanism upon receiving the reverse connection signal, i.e., controls the locking execution unit to be in the locked position to mechanically lock the mechanical closing and opening mechanism, i.e., limits the freedom of action of the mechanical closing and opening mechanism, so that the operating personnel cannot perform the "closing" operation on the mechanical closing and opening mechanism, thereby preventing the mechanical closing and opening mechanism from connecting the main circuit, and avoiding the risk of reverse connection and closing from the source. Therefore, the DC circuit breaker provided by the present application can actively detect reverse connection and forcibly prevent closing or immediately open the lock in the reverse connection state, forming an intelligent safety closed loop of "reverse connection and locking", converting the risk of human error into automatic and forced intervention of the system, effectively avoiding major equipment damage and personal safety accidents caused by polarity reverse connection, and improving the fault tolerance and safety of the system.
[0045] Optionally, as shown in Figure 2 , a structure schematic diagram of the mechanical closing and opening mechanism 4 in the DC circuit breaker 100 provided by the present application is shown. As shown in Figure 2 , the mechanical closing and opening mechanism 4 includes an operating member 41 and a contact unit 42. The contact unit 42 includes a movable contact, a fixed contact, and a connecting member provided on the movable contact. The operating member 41 is an external driving component. For example, the operating member 41 can be a handle, which is used to transmit the closing / opening instruction.
[0046] The movable contact is a movable conductive contact that approaches or moves away from the fixed contact under the driving of the operating member 41. The fixed contact is a fixed conductive contact that is usually connected to the input or output terminal. The connecting member is a transmission intermediate (such as a rotating shaft, a pull rod, a hinge, etc.) installed on the movable contact and serving as the transmission intermediate between the movable contact and the operating member 41.
[0047] When the locking execution unit 3 is in the locked position, the locking execution unit 3 mechanically limits the movement of the operating member and / or the connecting member, so that the operating member 41 cannot push the connecting member to drive the movable contact and the fixed contact to close, so that the movable contact and the fixed contact remain in the open position. For example, when the locking execution unit 3 is in the locked position, the rotation of the operating member 41 is blocked, so that the operating member 41 cannot push the connecting member.
[0048] In an implementable manner, if it is detected that the positive and negative electrodes are connected reversely, the locking execution unit 3 is in a locked position (such as the electromagnetic iron is attracted, the bayonet is inserted, the block is extended, etc.), at this time, the locking execution unit 3 forms a physical constraint (for example, locks the rotating shaft or sliding track thereof) to the operating member 41, so that the operating member 41 cannot drive the connecting member to move the movable contact towards the static contact; even if the user tries to operate the handle or sends a remote closing signal, the operating member 41 is fixed and cannot act, thus cannot drive the movable contact to move through the connecting member, so that the movable contact and the static contact always remain in a separated state (i.e., an open position), preventing the closing or keeping the opening of the contact unit, and realizing the safety isolation of the main circuit.
[0049] Therefore, by the locking execution unit 3 being in the locked position, the transmission of the operating force between the operating member 41 and the connecting member is blocked, so that the movable contact and the static contact cannot be closed, and the breaking of the main circuit is realized.
[0050] It should be noted that in the present application, the locking execution unit 3 can lock any one of the operating member, the movable contact, the static contact and the connecting member, so that the locking execution unit 3 can mechanically lock the mechanical closing and opening mechanism 4 when in the locked position, and realize the opening locking of the main circuit.
[0051] Optionally, when the locking execution unit 3 is in the reset position, the operating member 41 can mechanically push the connecting member, so that the movable contact and the static contact are in a closed position.
[0052] In another implementable manner, if it is detected that the positive and negative electrodes are connected correctly, the locking execution unit 3 is in a reset position, which can also be called a “release state”, at this time, the operating member 41 can move freely, that is, when the user issues a closing instruction (manually or electrically), the operating member 41 pushes the connecting member to move the movable contact towards the static contact, and the contact unit can normally perform the closing and opening operation.
[0053] Optionally, the reverse connection detection unit 1 comprises a voltage detection module. The detection of whether the DC circuit breaker 100 is in a reverse connection state comprises: The power supply voltage of the DC circuit breaker 100 is collected, and a pre-set voltage threshold value is obtained; according to the comparison result of the power supply voltage of the DC circuit breaker 100 and the voltage threshold value, it is determined whether the DC circuit breaker 100 is in a reverse connection state.
[0054] Wherein, a voltage threshold value Vth is pre-set, which is usually a small positive value (for example, ±5V or ±10% rated voltage), which is used to distinguish noise from real reverse connection signal, and the voltage threshold value supports adaptive adjustment.
[0055] In an implementable manner, the two ends of the voltage detection module are respectively connected to the incoming line end A1 and the incoming line end A2, the power supply voltage Vin of the DC circuit breaker 100 is collected in real time, and the power supply voltage Vin of the DC circuit breaker 100 is compared with the voltage threshold Vth. If the power supply voltage Vin of the DC circuit breaker 100 is greater than +Vth, it is determined that the polarity is correct (positive connection). If the power supply voltage Vin of the DC circuit breaker 100 is less than -Vth, it is determined that the polarity is opposite (negative connection), that is, it is determined as a negative connection state. Therefore, by detecting the power supply voltage of the DC circuit breaker 100 in real time, reliable judgment can be realized, and the problem of "equipment damage caused by manual wiring error" is solved.
[0056] Optionally, in order to ensure the accuracy of the detection result, whether the DC circuit breaker 100 is in the negative connection state can be determined based on the power supply voltage of the DC circuit breaker 100 detected for multiple times in succession.
[0057] Optionally, the negative connection detection unit 1 comprises a photocoupler detection module. The photocoupler detection module is a detection circuit composed of one or more photocoupler devices, the input side of which is connected to the incoming line end and / or the outgoing line end of the DC circuit breaker 100, and the output side of which is connected to the control unit 2, for transmitting the negative connection state information through an optical signal.
[0058] Detecting whether the DC circuit breaker 100 is in the negative connection state comprises: Obtaining the on-off state of the photocoupler device in the photocoupler detection module; and determining whether the DC circuit breaker 100 is in the negative connection state according to the on-off state of the photocoupler device.
[0059] In an implementable manner, as shown in Figure 3 The photocoupler detection module comprises a light-emitting diode, a photosensitive transistor (or a photosensitive triode) and a current-limiting resistor. The anode of the light-emitting diode is connected to the incoming line end A1, the cathode of the light-emitting diode is connected to the incoming line end A2, one end of the current-limiting resistor is connected to the incoming line end A2, the other end of the current-limiting resistor is connected to the cathode of the light-emitting diode, and the two ends of the photosensitive transistor are respectively connected to the control unit 2. When the power supply polarity of the DC circuit breaker 100 is correct, the light-emitting diode is forwardly conducted and emits light, and the photosensitive transistor is also conducted, outputting a signal that the power supply voltage of the DC circuit breaker 100 is in correct connection to the control unit 2. If the power supply of the DC circuit breaker 100 is in negative connection, the light-emitting diode cannot be conducted and does not emit light, and the photosensitive transistor is cut off, outputting a signal that the power supply voltage of the DC circuit breaker 100 is in negative connection to the control unit 2.
[0060] In another implementable manner, in order to avoid the light-emitting diode being in the light-emitting state for a long time, the anode of the light-emitting diode is connected to the incoming line end A2, the cathode of the light-emitting diode is connected to the incoming line end A1, when the power supply of the DC circuit breaker 100 is reversely connected, the light-emitting diode is forwardly conducted and emits light, and the phototransistor is also conducted to output a reverse connection signal of the power supply voltage of the DC circuit breaker 100 to the control unit 2.
[0061] Therefore, in the embodiment, whether the DC circuit breaker 100 is in the reverse connection state can be determined by detecting the on-off state of the optocoupler device in the optocoupler detection module, and when the optocoupler device is in the off state, it is determined that the DC circuit breaker 100 is in the reverse connection state.
[0062] Optionally, the reverse connection detection unit 1 is further configured to generate and output a normal connection signal if it is detected that the DC circuit breaker 100 returns to the normal connection state, and transmit the normal connection signal to the control unit 2. The control unit 2 is further configured to control the locking execution unit 3 to be in the reset position according to the normal connection signal, so as to release the mechanical locking of the mechanical combining and separating mechanism 4, and enable the mechanical combining and separating mechanism 4 to be mechanically connected to the main circuit.
[0063] Optionally, when the reverse connection fault of the DC circuit breaker 100 is eliminated and the power supply returns to the normal connection state, the system not only can identify the state change, but also can actively output the normal connection signal and trigger a series of subsequent actions to realize the automatic unlocking of the mechanical combining and separating mechanism 4 and the recovery of the operation permission, thereby reducing manual intervention.
[0064] Specifically, when the reverse connection detection unit 1 detects that the power supply polarity of the DC circuit breaker 100 is normal, it is determined that the DC circuit breaker 100 returns to the normal connection state, and the normal connection signal is generated and output, that is, the reverse connection detection unit 1 has a bidirectional state recognition capability; the control unit 2 sends a reset instruction to the locking execution unit 3 according to the normal connection signal, and the locking execution unit 3 is switched from the locking position to the reset position under the action of the reset instruction, so as to release the mechanical locking of the mechanical combining and separating mechanism 4, that is, the mechanical combining and separating mechanism 4 can be freely operated, and further enables the mechanical combining and separating mechanism 4 to be mechanically connected to the main circuit, thereby realizing the hard interlocking that the closing is allowed only after the fault is eliminated and improving the safety of the system.
[0065] Optionally, as shown in Figure 4 The DC circuit breaker 100 further comprises a power supply unit 6. The input end of the power supply unit 6 is configured to be connected to the incoming line end, the outgoing line end or an external auxiliary power supply of the DC circuit breaker 100. The output end of the power supply unit 6 is electrically connected with the reverse connection detection unit 1, the control unit 2 and the locking execution unit 3 respectively. The power supply unit 6 is configured to obtain an electrical energy signal from the incoming line end, the outgoing line end or an external auxiliary power supply of the DC circuit breaker 100, and transmit the electrical energy signal to the reverse connection detection unit 1, the control unit 2 and the locking execution unit 3, so as to provide electrical energy for the reverse connection detection unit 1, the control unit 2 and the locking execution unit 3.
[0066] In an implementable manner, in order to provide continuous and reliable working power supply for the reverse connection detection unit 1, the control unit 2 and the locking execution unit 3, the power supply mode of the circuit breaker is main loop power supply or / and auxiliary power supply, and the DC circuit breaker 100 further comprises a power supply unit 6. The power supply unit 6 is configured to obtain an electrical energy signal from the incoming line end (i.e. the power supply side), the outgoing line end (i.e. the load side) or an external auxiliary power supply (i.e. an independent low-voltage power supply such as DC 24V / 48V) of the DC circuit breaker 100, and transmit the electrical energy signal to the reverse connection detection unit 1, the control unit 2 and the locking execution unit 3, so as to provide electrical energy for the reverse connection detection unit 1, the control unit 2 and the locking execution unit 3, to ensure that the reverse connection detection unit 1, the control unit 2 and the locking execution unit 3 can work normally, realize multi-source redundant power supply, ensure uninterrupted power supply for reverse connection detection and mechanical locking, and improve system availability and safety.
[0067] Optionally, as shown in Figure 5 The power supply unit 6 comprises a rectification unit 61 and a power supply circuit 62. The rectification unit 61 can be a bridge rectification circuit (full-wave rectification bridge) composed of four diodes in an H-bridge structure. The power supply circuit 62 can be a DC-DC power supply circuit, which is configured to output a plurality of different voltages based on the rectification voltage, so as to supply power to different units in the DC circuit breaker 100, and the power supply circuit 62 is an isolated power supply circuit or a non-isolated power supply circuit.
[0068] The input end of the rectification unit 61 is connected to the incoming line end, the outgoing line end or the external auxiliary power supply of the DC circuit breaker 100, the output end of the rectification unit 61 is connected to the input end of the power supply circuit 62, and the output end of the power supply circuit 62 is electrically connected to the reverse connection detection unit 1, the control unit 2 and the locking execution unit 3, respectively. The rectification unit 61 is configured to rectify the accessed DC power supply or external auxiliary power supply, generate a rectified voltage signal, and output the rectified voltage signal to the power supply circuit 62. Therefore, the rectification unit 61 can perform polarity adaptive rectification on the accessed DC power supply (regardless of the incoming line end, the outgoing line end or the auxiliary power supply), output a fixed-polarity DC voltage signal, and supply the subsequent power supply circuit 62.
[0069] The power supply circuit 62 is configured to output the rectified voltage signal to the reverse connection detection unit 1, the control unit 2 and the locking execution unit 3.
[0070] In an implementable manner, referring to Figure 6 As shown in the figure, the rectifier unit 61 includes a rectifier unit one and a rectifier unit two. Specifically, when the power polarity of the DC circuit breaker 100 is connected correctly, the input end of the rectifier unit one can be connected to the incoming line end A1 / A2, and the output end of the rectifier unit one is connected to the input end of the DCDC power supply circuit, that is, the DC power supply signal can be obtained from the incoming line end A1 / A2 of the DC circuit breaker 100, and the DC power supply incoming line is rectified by the rectifier unit one. When the power polarity of the DC circuit breaker 100 is reversed, the input end of the rectifier unit two can be connected to the outgoing line end B1 / B2, and the output end of the rectifier unit two is connected to the input end of the DCDC power supply circuit, that is, the DC power supply signal can be obtained from the outgoing line end B1 / B2 of the DC circuit breaker 100, and the DC power supply incoming line is rectified by the rectifier unit two. Therefore, even if the main circuit is reversed, the rectifier unit two can still output a forward voltage to ensure the power supply of the control system in the rear stage.
[0071] Referring to Figure 7 As shown in the figure, the input end of the rectifier unit three can be connected to an external auxiliary power supply, the electrical energy signal provided by the external auxiliary power supply is rectified by the rectifier unit three to generate a rectified voltage signal, and the rectified voltage signal is output to the DCDC power supply circuit, and the rectified voltage signal is output to the reverse connection detection unit 1, the control unit 2 and the locking execution unit 3, to ensure the normal operation of different units in the DC circuit breaker 100.
[0072] Optionally, the locking execution unit 3 includes an electrical drive unit and a mechanical unit. The electrical drive unit can convert the "locking instruction" or "reset instruction" (such as high and low levels, pulse signals, PWM, etc.) output by the control unit 2 into mechanical power output, which is used to drive the mechanical unit to move between the locking position and the reset position.
[0073] The electrical drive unit and the mechanical unit are mechanically connected. The electrical drive unit is used to drive the mechanical unit to move between the locking position and the reset position to realize the locking and unlocking functions.
[0074] In an implementable manner, when the electrical drive unit receives the "locking instruction" sent by the control unit 2, such as a high level, the electrical drive unit drives the mechanical unit to move to the locking position under the action of the high level; when the electrical drive unit receives the "reset instruction" sent by the control unit 2, such as a low level, the electrical drive unit drives the mechanical unit to move to the reset position under the action of the low level, realizing the switching between the locking position and the reset position.
[0075] The electric drive unit adopts a bidirectional magnetic holding coil. The bidirectional magnetic holding coil is controlled by a pulse driving signal to enable the locking execution unit 3 to be stably kept in the locking position or the reset position. Alternatively, the electric drive unit can also adopt a common coil or a driving motor. When the common coil is adopted, the locking execution unit 3 is kept in the locking position by continuously inputting current to drive the coil. When the driving motor is adopted, the locking execution unit 3 is kept in the locking position by rotating the driving motor to drive the mechanical unit to move.
[0076] Optionally, as shown in Figure 8 The application further provides a control method of the DC circuit breaker. The method is applied to the reverse connection detection unit of the DC circuit breaker provided in the above embodiments. The method comprises the following steps: S101, detecting whether the DC circuit breaker is in a reverse connection state.
[0077] S102, if yes, generating and outputting a reverse connection signal, transmitting the reverse connection signal to the control unit, so that the control unit controls the locking execution unit to be in the locking position to mechanically lock the mechanical combining and dividing mechanism, so that the mechanical combining and dividing mechanism cannot manually push the operating member to connect the main circuit.
[0078] The reverse connection signal can be a high-level pulse.
[0079] In an implementable manner, the reverse connection detection unit is used to detect whether the power polarity of the DC circuit breaker is reversed in real time. If yes, it is determined that the DC circuit breaker is in a reverse connection state, and a reverse connection signal is generated and output. The reverse connection signal is transmitted to the control unit through a communication bus. The control unit receives the reverse connection signal and sends a “locking instruction” to the locking execution unit according to the reverse connection signal. The locking execution unit switches to the locking position under the action of the “locking instruction” to mechanically lock the mechanical combining and dividing mechanism. Even if the operating member is manually pushed to close the circuit or remotely ordered to close the circuit, the mechanical combining and dividing mechanism cannot perform the closing operation, so that the mechanical combining and dividing mechanism cannot connect the main circuit, thereby avoiding safety accidents such as large current short circuit, arc light, and fire caused by the reverse connection of the power polarity, and improving the system safety.
[0080] The above only describes the preferred embodiments of the application and is not used to limit the application. For those skilled in the art, the application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application shall be included in the protection scope of the application.
[0081] It will be apparent to those skilled in the art that the application is not limited to the details of the above-exemplified embodiments and that the present application can be implemented in other particular forms without departing from the spirit or essential characteristics thereof. The embodiments should be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the above description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. No reference herein to any prior art is to be taken as an admission that the application is not entitled to antedate such prior art by virtue of prior application. Any reference to the use of a term in the singular herein shall also be taken to refer to the plural, and vice versa, unless otherwise indicated by context. Any reference to the use of a term in the present application shall be taken to refer to the use of the term in the context of the present application, and not to the use of the term in any other context. Any reference to the use of a term in the present application shall be taken to refer to the use of the term in the context of the present application, and not to the use of the term in any other context.
Claims
1. A DC circuit breaker, characterized in that, The DC circuit breaker includes: a reverse connection detection unit, a control unit, a locking execution unit, and a mechanical opening and closing mechanism; The input terminal of the reverse connection detection unit is connected to the input terminal and / or output terminal of the DC circuit breaker; The output terminal of the reverse connection detection unit is connected to the input terminal of the control unit, and the output terminal of the control unit is connected to the input terminal of the locking execution unit. The two ends of the mechanical combining and separating mechanism are respectively connected to the main circuit; The reverse connection detection unit is used to detect whether the DC circuit breaker is in a reverse connection state. If so, it generates and outputs a reverse connection signal and transmits the reverse connection signal to the control unit. The control unit is configured to control the locking execution unit to be in the locked position according to the reverse connection signal, so as to mechanically lock the mechanical opening and closing mechanism so that the mechanical opening and closing mechanism cannot connect the main circuit.
2. The DC circuit breaker according to claim 1, characterized in that, The mechanical opening and closing mechanism includes: an operating element and a contact unit, wherein the contact unit includes: a moving contact, a stationary contact, and a connecting element disposed on the moving contact; When the locking execution unit is in the locked position, the operating member cannot push the connecting member so that the moving contact and the stationary contact remain in the open position.
3. The DC circuit breaker according to claim 2, characterized in that, When the locking execution unit is in the reset position, the operating member can mechanically push the connecting member so that the moving contact and the stationary contact are in the closed position.
4. The DC circuit breaker according to claim 1, characterized in that, The reverse connection detection unit includes: a voltage detection module; The detection of whether the DC circuit breaker is in a reverse connection state includes: The power supply voltage of the DC circuit breaker is collected, and a preset voltage threshold is obtained; Based on the comparison between the power supply voltage of the DC circuit breaker and the voltage threshold, it is determined whether the DC circuit breaker is in a reverse connection state.
5. The DC circuit breaker according to claim 1, characterized in that, The reverse connection detection unit includes: an optical coupler detection module; The detection of whether the DC circuit breaker is in a reverse connection state includes: Obtain the on / off state of the optocoupler device in the optocoupler detection module; Based on the on / off state of the optocoupler, determine whether the DC circuit breaker is in a reverse connection state.
6. The DC circuit breaker according to claim 1, characterized in that, The reverse connection detection unit is also used to generate and output a normal connection signal if the DC circuit breaker is detected to have returned to normal connection status, and to transmit the normal connection signal to the control unit. The control unit is further configured to control the locking execution unit to be in a reset position according to the normal connection signal, so as to release the mechanical locking of the mechanical engagement and disengagement mechanism, so that the mechanical engagement and disengagement mechanism can be mechanically connected to the main circuit.
7. The DC circuit breaker according to claim 1, characterized in that, The DC circuit breaker also includes: a power supply unit; The input terminal of the power supply unit is used to connect to the input terminal, output terminal or external auxiliary power supply of the DC circuit breaker; The output terminal of the power supply unit is electrically connected to the reverse connection detection unit, the control unit and the locking execution unit respectively; The power supply unit is used to obtain power signals from the incoming terminal, outgoing terminal or external auxiliary power supply of the DC circuit breaker, and transmit the power signals to the reverse connection detection unit, the control unit and the locking execution unit to provide power to the reverse connection detection unit, the control unit and the locking execution unit.
8. The DC circuit breaker according to claim 7, characterized in that, The power supply unit includes: a rectifier unit and a power supply circuit; The input terminal of the rectifier unit is connected to the input terminal, output terminal or external auxiliary power supply of the DC circuit breaker, the output terminal of the rectifier unit is connected to the input terminal of the power supply circuit, and the output terminal of the power supply circuit is electrically connected to the reverse connection detection unit, the control unit and the locking execution unit respectively. The rectifier unit is used to rectify the connected DC power supply or external auxiliary power supply, generate a rectified voltage signal, and output the rectified voltage signal to the power supply circuit. The power supply circuit is used to output the rectified voltage signal to the reverse connection detection unit, the control unit, and the locking execution unit.
9. The DC circuit breaker according to claim 1, characterized in that, The locking execution unit includes: an electric drive unit and a mechanical unit; The electric drive unit is mechanically connected to the mechanical unit; The electric drive unit is used to drive the mechanical unit to move between the locked position and the reset position.
10. A control method for a DC circuit breaker, characterized in that, The reverse connection detection unit applied in the DC circuit breaker according to any one of claims 1-9, the method comprising: Check if the DC circuit breaker is in a reverse connection state; If so, a reverse connection signal is generated and output, and the reverse connection signal is transmitted to the control unit so that the control unit controls the locking execution unit to be in the locked position according to the reverse connection signal, and mechanically locks the mechanical opening and closing mechanism so that the mechanical opening and closing mechanism cannot be manually pushed to connect the main circuit.