A timing control system and device of a hybrid solid-state DC circuit breaker and the circuit breaker

Abstract

The application discloses a timing control system and device of a hybrid solid-state direct-current circuit breaker and the circuit breaker, and belongs to the technical field of circuit breakers. The timing control system comprises a power-taking unit, a pulse unit, a voltage-reducing unit and a control unit. The power-taking unit is used for storing power in a conduction with a direct-current system at a first position in a circuit breaker closing process. The voltage-reducing unit is used for reducing the voltage of the power-taking unit and then functions the pulse unit and the control unit. The pulse unit is used for sending a pulse signal at a second position in the circuit breaker closing process. The circuit breaker closing process sequentially passes through the first position and the second position. The control unit is used for sending a control signal according to the pulse signal of the pulse unit, so that an electronic branch of the circuit breaker is first conducted. The system controls the mechanical branch and the electronic branch of the circuit breaker and works according to a specified sequence of the hybrid solid-state circuit breaker, so as to improve the working reliability of the hybrid circuit breaker and ensure the safety of the direct-current system.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit breakers, and in particular to a timing control system, a device and a circuit breaker of a hybrid solid-state DC circuit breaker. Background Art

[0002] Existing low-voltage circuit breakers used in DC systems often require multi-pole series connection or an amplified arc-extinguishing system to achieve optimal performance. As product performance requirements become increasingly stringent, traditional products are no longer able to meet these demands. Currently, a growing number of low-voltage electrical equipment manufacturers are researching solid-state circuit breakers, and some purely solid-state circuit breaker products have emerged. However, due to their high cost, they have not been widely adopted. This is primarily due to the significant heat dissipation issue, which requires cooling devices. Therefore, only low-current products (under 80A) can be put into commercial use. This has led to the emergence of hybrid solid-state circuit breakers, which combine the advantages of traditional mechanical circuit breakers and solid-state circuit breakers.

[0003] Hybrid solid-state circuit breakers utilize electronic components to intervene when a mechanical circuit breaker opens. During the opening process, the mechanical contacts are disconnected, and the IGBT (Insulated Gate Bipolar Transistor) is then switched on. Under arc voltage, the current is diverted to the power electronics, rapidly extinguishing the arc between the contacts. After the power electronics shut down, the current is diverted to the energy-consuming MOV (Metal Oxide Voltage Transistor), clearing the fault current. However, the closing process is less discussed. As the contact spacing decreases during closing, arcing can occur, exacerbating contact erosion and reducing electrical life.

[0004] In order to solve the problem of reduced electrical life caused by arc burning, it is necessary to first turn on the power electronic devices during the closing process, so that the mechanical contacts are closed under zero current and voltage conditions. At the same time, during the opening process, the current transfer is completed as quickly as possible to reduce the arcing time. Therefore, a timing control structure is required to control the mechanical and electronic branches of the circuit breaker and operate them in the specified sequence of the hybrid solid-state circuit breaker to improve the operating reliability of the hybrid circuit breaker and ensure the safety of the DC system. Summary of the Invention

[0005] In response to the problems existing in the prior art, the present invention provides a timing control system, device, and circuit breaker for a hybrid solid-state DC circuit breaker. By controlling the mechanical and electronic branches of the circuit breaker, the hybrid solid-state circuit breaker operates in a specified sequence, thereby improving the operating reliability of the hybrid circuit breaker and ensuring the safety of the DC system.

[0006] The present invention is achieved through the following technical solutions:

[0007] In a first aspect, the present application provides a timing control system for a hybrid solid-state DC circuit breaker, comprising an energy taking unit, a pulse unit, a voltage reducing unit, and a control unit;

[0008] The energy taking unit is used to connect with the DC system to store energy in the first position during the circuit breaker closing process;

[0009] The step-down unit is used to step down the voltage of the energy taking unit and then supply energy to the pulse unit and the control unit;

[0010] a pulse unit, configured to send a pulse signal at a second position during the closing process of the circuit breaker, the circuit breaker passing through the first position and the second position in sequence during the closing process;

[0011] The control unit is used to send a control signal according to the pulse signal of the pulse unit, so that the electronic branch of the circuit breaker is turned on first.

[0012] Furthermore, the energy acquisition unit is connected to the positive pole A of the DC system and the load B respectively. The energy acquisition unit is connected to the positive pole A of the DC system via an auxiliary switch Q2, and the auxiliary switch Q2 is located in the first position.

[0013] Furthermore, the energy acquisition unit is connected to the pulse unit via a dial switch Q1, and the dial switch Q1 is placed in the second position.

[0014] Furthermore, the energy acquisition unit is connected to the control unit via a conditioning unit;

[0015] The conditioning unit detects the voltage of the energy storage unit and sends a voltage signal to the control unit. When the voltage reaches a threshold, the control unit sends a control signal.

[0016] Furthermore, the control unit is connected to the electronic branch of the circuit breaker via a driving unit, and the driving unit controls the conduction state of the IGBT of the electronic branch.

[0017] In a second aspect, the present application provides a timing control device for a hybrid solid-state DC circuit breaker, characterized in that it comprises a push rod and the timing control system according to any one of claims 1 to 6;

[0018] The push rod is connected to the operating mechanism of the circuit breaker and rotates synchronously. During the closing process, the push rod passes through the first position and the second position of the circuit breaker in sequence, and the timing control system is connected to the electronic branch of the circuit breaker.

[0019] Furthermore, a dial switch Q1 and an auxiliary switch Q2 are installed on the circuit breaker respectively;

[0020] The auxiliary switch Q2 is installed at the first position of the circuit breaker, and the dial switch Q1 is installed at the second position of the circuit breaker.

[0021] In a third aspect, the present application provides a hybrid solid-state DC circuit breaker, characterized in that it includes the timing control system.

[0022] In a fourth aspect, the present application provides a high-voltage electrical device, including the hybrid solid-state DC circuit breaker.

[0023] Compared with the prior art, the present invention has the following beneficial technical effects:

[0024] The present invention provides a timing control system. During the closing process of the circuit breaker, the energy acquisition unit is first connected to the DC system to store energy and supply energy to each unit. During the continued closing process, the pulse unit is triggered to send a pulse signal to the control unit. The control unit sends a control signal based on the voltage and pulse signal of the energy acquisition unit to turn on the IGBT of the electronic branch of the circuit breaker. At this time, no current passes through the mechanical switch. When the mechanical switch is closed, the current is commutated to the mechanical switch, so that the mechanical contacts are closed under zero current and voltage conditions, thereby solving the problem of arc burning of the moving and static contacts of the mechanical switch during the closing process, and the problem of reduced electrical life caused by arc burning. The system controls the mechanical branch and electronic branch of the circuit breaker to operate in the specified sequence of the hybrid solid-state circuit breaker, so as to improve the working reliability of the hybrid circuit breaker and ensure the safety of the DC system.

[0025] The present application also proposes a timing control device, a hybrid solid-state DC circuit breaker and a high-voltage electrical equipment, which have all the advantages of the above-mentioned timing control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 is a structural diagram of the timing control device of the present invention;

[0028] Figure 2 is a schematic diagram of the timing control device of the present invention;

[0029] Figure 3 Schematic diagram of the structure of the circuit breaker of the present invention;

[0030] Figure 4 It is a structural diagram of the DIP switch of the present invention;

[0031] Figure 5 This is a structural diagram of the auxiliary switch in each state of the present invention;

[0032] Figure 6 is a structural diagram of the circuit breaker operating mechanism of the present invention;

[0033] Figure 7 This is a structural diagram of the push rod and auxiliary switch of the present invention;

[0034] Figure 8 This is a structural diagram of the push rod and the DIP switch of the present invention;

[0035] Figure 9 This is a structural diagram of the circuit breaker in the open state of the present invention;

[0036] Figure 10 This is a structural diagram of the hybrid solid-state DC circuit breaker of the present invention.

[0037] In the figure: 1, push rod; 2, rotating shaft; Q1, dip switch; Q2, auxiliary switch; K, mechanical switch; K1, moving contact; K2, static contact; M, hybrid solid-state DC molded case circuit breaker; E, timing control system. DETAILED DESCRIPTION

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0039] 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 present application for protection, but merely represents selected embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in the present application without creative work are within the scope of protection of the present application.

[0040] The molded case circuit breaker includes a cover, a base, an operating mechanism, an arc extinguishing unit box and a trip unit; the three contact arc extinguishing unit boxes are placed side by side and installed in the base, the three contact arc extinguishing unit boxes are connected to the operating mechanism, and the operating mechanism controls the three contact arc extinguishing unit boxes to perform opening and closing actions. The trip unit is connected to the contact arc extinguishing unit box and is located at the bottom, and the cover is set on the top of the base to form an integral structure.

[0041] When the circuit needs to be disconnected, the operating mechanism receives the opening command. Upon receiving the command, the opening iron core inside the operating mechanism activates, and the operating mechanism's rotating shaft moves, separating the contacts from the static contacts, thereby disconnecting the circuit. During this contact separation process, the arc-extinguishing medium (such as air, inert gas, or oil) within the arc-extinguishing unit box begins to work, extinguishing any arc that may have occurred. Simultaneously, the oil-distributing damper at the end of the conductive rod activates, slowing the rod's movement and ensuring smooth contact separation. After contact separation, the trip unit activates to ensure the circuit breaker remains in the open state.

[0042] When the circuit needs to be closed, the operating mechanism receives a closing command, and the operating mechanism's rotating shaft moves, causing the contacts to come into close contact with the static contacts, thereby closing the circuit.

[0043] See Figure 1-10 , a timing control system for a hybrid solid-state DC circuit breaker, comprising an energy taking unit, a pulse unit, a conditioning circuit, a control unit, a drive unit and a step-down unit;

[0044] Energy taking unit, used to conduct with the DC system to store energy during the circuit breaker closing process;

[0045] Pulse unit, used to send pulse signals during the circuit breaker closing process;

[0046] A conditioning unit, used for detecting the voltage of the energy storage unit;

[0047] The step-down unit is used to supply energy to the pulse unit, the control unit and the drive unit through the energy taking unit;

[0048] The control unit is used to send a control signal according to the pulse signal of the pulse unit and the voltage signal of the energy-taking unit sent by the conditioning unit, so that the electronic branch of the circuit breaker is turned on first.

[0049] In this timing control system, during the closing process of the circuit breaker, the energy acquisition unit is first connected to the DC system to store energy and supply energy to each unit. During the continued closing process, the pulse unit is triggered to send a pulse signal to the control unit. The control unit sends a control signal based on the voltage and pulse signal of the energy acquisition unit to turn on the IGBT of the electronic branch of the circuit breaker. No current flows through the mechanical switch. When the mechanical switch is closed, the current is commutated to the mechanical switch, so that the mechanical contacts are closed under zero current and voltage conditions. This solves the problem of arcing and burning the moving and static contacts of the mechanical switch during the closing process, as well as the problem of reduced electrical life caused by arc burning.

[0050] During the tripping process, the mechanical switch is disconnected, the IGBT of the power branch is turned on, and under the action of arc voltage, the current is commutated to the power electronic device. The arc between the contacts is quickly extinguished. After the power electronic device is turned off, the current is commutated to the energy consumption branch MOV, completing the fault current clearing.

[0051] In some embodiments, the energy acquisition unit is connected to the positive electrode A of the DC system and the load B, respectively, and the energy acquisition unit is charged through the voltage drop across AB.

[0052] The energy acquisition unit is connected to the positive pole A of the DC system through the dial switch Q1. When the circuit breaker is closed, the dial switch Q1 is triggered to close and the energy acquisition unit is charged.

[0053] In some embodiments, the energy acquisition unit is connected to the pulse unit through the auxiliary switch Q2. The dial switch Q1 is used to detect the closing action of the circuit breaker. The circuit breaker triggers the dial switch Q1 during the closing process, and the pulse unit sends a pulse signal, indicating that the circuit breaker is closing. It should be noted that the dial switch Q1 is not triggered during the opening process of the circuit breaker.

[0054] In some embodiments, the conditioning circuit is used to detect the voltage of the energy storage unit and send it to the control unit. The control unit determines whether the voltage of the energy acquisition unit reaches a threshold value. When the threshold value is reached, a control signal is sent in combination with a pulse signal. When the voltage does not reach the threshold value, it means that the voltage of the energy acquisition unit does not reach the normal operating voltage of the driver chip and cannot drive the electronic branch.

[0055] In some embodiments, the control unit adopts a single chip microcomputer, which sends a control signal to the driving unit, and the driving unit drives the IGBT to turn on and provide a driving voltage signal;

[0056] In some embodiments, the step-down unit includes a DC / DC converter M1 and a DC / DC converter M2, and the energy taking unit is connected to the control unit and the driving unit through the two converters.

[0057] Two DC / DC converters are used to convert the voltage of the energy-harvesting circuit into voltage signals for powering the driver IC and MCU, with standard values ​​of 15V and 3.3V respectively. The pulse trigger circuit is used to provide a 3.3V pulse voltage for MCU detection.

[0058] Example 1

[0059] Correspondingly, the present application also provides a timing control device for a hybrid solid-state DC circuit breaker, comprising a push rod 1, a dial switch Q1, an auxiliary switch Q2 and a timing control system E.

[0060] Push rod 1 is installed on the outer contact arc extinguishing unit box. Figure 10 The middle push rod is installed on the right contact arc extinguishing unit box. The push rod 1 is fixed to the rotating shaft of the operating structure and rotates synchronously. The switch Q1 and switch Q2 are set on the circuit breaker and connected to the timing control unit. The dial switch Q1 and the auxiliary switch Q2 are located on the rotation track of the push rod 1 and are used to obtain the operating status of the circuit breaker. During the closing process of the circuit breaker, the auxiliary switch Q2 and the dial switch Q1 are triggered in sequence.

[0061] In this embodiment, auxiliary switch Q2 is mounted on the circuit breaker cover, and its contacts cooperate with the push rod. When the push rod is in the closed position, it triggers the contacts of auxiliary switch Q2 to the closed position, and transmits a continuous closed signal through the circuit. When the push rod is in the open position, auxiliary switch Q2 also moves to the open position, and transmits a continuous open signal through the circuit. The DIP switch Q1 is mounted on the contact arc extinguishing unit box. The DIP switch Q1 cooperates with the push rod. When the push rod switches from closed to open or from open to closed, it toggles the DIP switch once, generating a signal that is transmitted to the timing control unit.

[0062] The working principle of the timing control device of the hybrid solid-state DC circuit breaker is described in detail below.

[0063] The closing process of the hybrid solid-state circuit breaker is as follows:

[0064] 1. When receiving the closing command, the hybrid solid-state circuit breaker closes, the operating mechanism is activated, the shaft 2 drives the push rod 1 to rotate synchronously, and the auxiliary switch Q2 is triggered during the rotation process. The DC system is connected to the energy extraction unit and charged under the action of voltage.

[0065] 2. The shaft drives the push rod 1 to continue rotating in the closing direction. The push rod triggers the dial switch Q1. The pulse unit receives the rising edge signal and sends a pulse signal. The control unit receives the pulse signal and sends a control signal to the drive unit. The drive unit turns on the IGBT S1 of the electronic branch according to the control signal, so that the DC system and the load are turned on.

[0066] 3. The shaft drives the push rod 1 to continue rotating in the closing direction until the mechanical switch K is closed, that is, the moving contact K1 and the static contact K2 of the circuit breaker are in contact, the commutation unit of the electronic branch works to commutate, and the DC system is connected to the load through the mechanical switch K.

[0067] The tripping process of the hybrid solid-state circuit breaker is as follows:

[0068] 1. When receiving the opening command, the hybrid solid-state circuit breaker opens, the operating mechanism is activated, the mechanical switch K is disconnected, and an arc is generated between the moving and static contacts. At the same time, the energy extraction unit is charged.

[0069] The IGBT in the power branch is turned on and commutates. Under the action of arc voltage, the current is commutated to the power electronic device. The arc between the contacts is quickly extinguished. After the power electronic device is turned off, the current is commutated to the energy consumption branch MOV, completing the fault current clearing.

[0070] 2. The shaft drives the push rod 1 to continue rotating in the opening direction, and then triggers the DIP switch Q1 to operate. It should be noted that the DIP switch Q1 does not send a trigger signal at this time.

[0071] 3. The shaft drives the push rod 1 to continue rotating in the opening direction, triggering the auxiliary switch Q2 to separate and disconnect the energy taking unit.

[0072] See Figure 4 The head of the dip switch Q1 can be dialed once after the push rod passes, and then reset immediately. The reverse push will also dial it once in the reverse direction.

[0073] See Figure 5 The auxiliary switch can achieve several positions: open, closed, and closed overtravel. The overtravel generated during closing is used to implement the timing. When the mechanical contact K initially closes, auxiliary switch Q2 begins to supply energy. However, as the mechanical contact continues to move downward, continuing to energize DIP switch Q1 and finally closing, the excess travel is completed by the closed overtravel.

[0074] See Figure 7 and 8 The push rod includes a handle and a touch plate. One end of the handle is connected to the operating mechanism's shaft, and the other end is connected to the touch plate. Rotation of the touch plate triggers the DIP switch Q1 and auxiliary switch Q2. When the mechanical switch's moving contact closes, the shaft rotates along with it. This rotation of the shaft drives the push rod downward, cooperating with the touch plates of the DIP switch Q1 and auxiliary switch Q2.

[0075] Refer to Figures 9 and 10. The push rod's contact plate moves away from the small push rod of the Q2 auxiliary contact, causing auxiliary switch Q2 to send a signal, activating the energy extraction circuit on the circuit board. The large push rod's contact plate then hits DIP switch Q1, which is flipped briefly—not for a long time. This triggers a signal, turning on the IGBT. IGBT S1 commutates, minimizing circuit damage during closing. During opening, the signal generated by the mechanical switch opening activates the energy extraction circuit, initiating commutation. At this point, DIP switch Q1 and auxiliary switch Q2 are not active; they simply pass by. A few milliseconds after the final contacts open, commutation is complete. This completes the commutation required for disconnection.

[0076] Example 2

[0077] The present application also provides a hybrid solid-state DC circuit breaker, including a hybrid solid-state DC molded case circuit breaker M and a timing control device.

[0078] Example 3

[0079] The present application also provides a high-voltage electrical equipment, including the hybrid solid-state DC circuit breaker described in Example 2.

[0080] Example 4

[0081] An electric power system includes the high-voltage electrical equipment described in Example 3.

[0082] The power system includes substations, industrial power grids, distribution systems, high-voltage transmission grids, new energy power generation systems, etc.

[0083] The above content is only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A timing control system for a hybrid solid-state DC circuit breaker, characterized in that: It includes an energy taking unit, a pulse unit, a voltage reduction unit and a control unit; The energy taking unit is used to connect with the DC system to store energy in the first position during the circuit breaker closing process; The step-down unit is used to step down the voltage of the energy taking unit and then supply energy to the pulse unit and the control unit; a pulse unit, configured to send a pulse signal at a second position during the closing process of the circuit breaker, the circuit breaker passing through the first position and the second position in sequence during the closing process; A control unit, configured to send a control signal according to a pulse signal from the pulse unit, so that the electronic branch of the circuit breaker is first turned on; The energy taking unit is connected to the positive pole A of the DC system and the load B respectively. The energy taking unit is connected to the positive pole A of the DC system through the auxiliary switch Q2, and the auxiliary switch Q2 is in the first position; the energy taking unit is connected to the pulse unit through the dial switch Q1, and the dial switch Q1 is in the second position; The closing process of the circuit breaker is as follows: When the closing command is received, the circuit breaker closes, the operating mechanism is activated, and the shaft drives the push rod to rotate synchronously. During the rotation process, the auxiliary switch Q2 is triggered, and the DC system is connected to the energy extraction unit and charged under the action of voltage; The shaft drives the push rod to continue rotating in the closing direction. The push rod triggers the dial switch Q1. The pulse unit receives the rising edge signal and sends a pulse signal. The control unit receives the pulse signal and sends a control signal to the drive unit. The drive unit turns on the IGBT of the electronic branch according to the control signal, so that the DC system and the load are turned on. The rotating shaft drives the push rod to continue rotating in the closing direction until the mechanical switch K is closed, that is, the moving contact K1 and the static contact K2 of the circuit breaker are in contact, the commutation unit of the electronic branch works to commutate, and the DC system is connected to the load through the mechanical switch K.

2. The timing control system of a hybrid solid-state DC circuit breaker according to claim 1, characterized in that: The energy taking unit is connected to the control unit via the conditioning unit; The conditioning unit detects the voltage of the energy storage unit and sends a voltage signal to the control unit. When the voltage reaches a threshold, the control unit sends a control signal.

3. The timing control system of a hybrid solid-state DC circuit breaker according to claim 1, characterized in that: The step-down unit uses DC / DC conversion to perform step-down.

4. The timing control system of a hybrid solid-state DC circuit breaker according to claim 1, characterized in that: The control unit is connected to the electronic branch of the circuit breaker via a driving unit, and the driving unit controls the conduction state of the IGBT of the electronic branch.

5. A timing control device for a hybrid solid-state DC circuit breaker, characterized in that: comprising a push rod and a timing control system according to any one of claims 1 to 4; The push rod is connected to the operating mechanism of the circuit breaker and rotates synchronously. During the closing process, the push rod passes through the first position and the second position of the circuit breaker in sequence, and the timing control system is connected to the electronic branch of the circuit breaker.

6. The timing control device for a hybrid solid-state DC circuit breaker according to claim 5, characterized in that: The circuit breaker is respectively equipped with a dial switch Q1 and an auxiliary switch Q2; The auxiliary switch Q2 is installed at the first position of the circuit breaker, and the dial switch Q1 is installed at the second position of the circuit breaker.

7. A hybrid solid-state DC circuit breaker, characterized in that: Including the timing control system described in claim 5 or 6.

8. A high-voltage electrical equipment comprising the hybrid solid-state DC circuit breaker according to claim 7.

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