Integrated automatic reclosing device

Abstract

The utility model discloses an integrated automatic reclosing device which comprises a controller, a closing loop, a tripping loop, a current loop and a voltage loop. The controller is connected with the current loop and the voltage loop and used for obtaining the state of the circuit breaker. The controller outputs a closing signal and a tripping signal to the closing loop and the tripping loop; the current loop is connected with the controller and is used for transmitting a current detection result; and the voltage loop connects the three-phase power of the high-voltage side of the circuit breaker with the controller and is used for detecting whether the high-voltage side of the circuit breaker has voltage or not in real time. The integrated reclosing device provided by the utility model outputs electric closing signals and electric opening control signals of a circuit breaker, and various working state indicating lamp control signals; the relay is used for replacing the hierarchical action relationship of a traditional relay, so that the bad problems of transmission lagging, contact oxidation, adhesion and the like of the traditional relay are solved.

Description

Technical Field

[0001] This utility model belongs to the technical field of undervoltage protection devices, specifically relating to an integrated automatic reclosing device. Background Technology

[0002] The power supply company operates a wide variety of box-type transformers (referred to as box-type transformers). However, these box-type transformers have one thing in common during operation: when the box-type transformer experiences undervoltage or loss of voltage, the air circuit breaker in the low-voltage switchgear will trip and will not be able to automatically close.

[0003] Analysis and summarization of typical power outage events reveal that a significant proportion of outages are caused by low-voltage coil undervoltage due to undervoltage protection. When the low-voltage coil experiences undervoltage, the circuit breakers in the low-voltage switchgear will fail to operate, preventing the transformer substation from automatically reclosing. This severely impacts operational efficiency. The inability to automatically reclose the substation necessitates manual reclosing, resulting in a substantial workload for staff, unnecessary waste of manpower and resources, and compromised reliability and stability of the power grid. Utility Model Content

[0004] Therefore, in order to effectively solve the above problems, this utility model installs an integrated automatic reclosing device in the transformer substation, which has the functions of an undervoltage protection device, can effectively shorten the power supply time, and more importantly, can significantly improve the stability and reliability of the system operation.

[0005] Specifically, this utility model proposes an integrated automatic reclosing device for controlling a circuit breaker to reclose. The integrated automatic reclosing device includes a controller, a closing circuit, a tripping circuit, a current circuit, and a voltage circuit.

[0006] The controller is connected to the current loop and the voltage loop respectively, and is used to obtain the circuit breaker status;

[0007] The controller is connected to the closing circuit and the tripping circuit respectively, and is used to output closing signals and tripping signals;

[0008] The closing circuit is connected between the live wire and the neutral wire, and includes a closing air switch, a closing relay, and a closing coil; the closing relay, the closing air switch, and the closing coil are connected in series between the single-phase live wire and the neutral wire; the two ends of the closing relay are connected to the controller to obtain the closing signal; the closing air switch is a normally closed switch; the closing coil is matched with the circuit breaker, and when the closing coil is energized, the circuit breaker closes.

[0009] The tripping circuit is connected between the live wire and the neutral wire, and includes a tripping air switch, a tripping relay, and a tripping coil; the tripping relay, the tripping air switch, and the tripping coil are connected to the neutral wire in sequence by a single-phase live wire; the two ends of the tripping relay are connected to the controller to obtain the tripping signal; the tripping air switch is a normally open switch; the tripping coil is matched with the tripping relay to perform the tripping operation;

[0010] The current loop includes a three-phase current transformer and a zero-sequence current transformer. The three-phase current transformers are located on the incoming side of the circuit breaker and consist of three transformers: phase A, phase B, and phase C. The phase A, phase B, and phase C transformers respectively detect whether the current in the three-phase busbars exceeds the normal operating range. The zero-sequence current transformer is located on the incoming side of the circuit breaker, and all three phase busbars pass through the coil of the zero-sequence current transformer. The coil of the zero-sequence current transformer is used to detect whether the three-phase circuit is balanced. The current loop is connected to a controller to transmit the current detection results.

[0011] The voltage circuit includes three single-phase detection circuits. Each single-phase detection circuit includes an optocoupler, resistors R1, R2, R3, R4, R5, and R6, and capacitor C6. The optocoupler includes a live wire interface, a neutral wire interface, a power supply interface, a signal output interface, and a ground interface. The single-phase voltage input terminal, resistors R1, R2, and R3 are connected in series and input to the optocoupler live wire interface. The neutral wire interface is connected to the neutral wire through resistor R4. Resistor R5 is connected in parallel with the optocoupler power supply interface and the signal output interface. The optocoupler power supply interface is connected to the power supply, and the signal output interface is connected to the controller input terminal. One end of capacitor C6 and resistor R6 is connected to the optocoupler signal output interface, and the other end of capacitor C6 and resistor R6 is grounded.

[0012] Furthermore, the integrated automatic reclosing device is also equipped with an event recording module, which can detect and record the status information and voltage data of the circuit breaker at the moment of undervoltage trip in real time, and judge the instantaneous fault and permanent fault of the circuit breaker, thereby achieving accurate reclosing to prevent accidental power supply.

[0013] Furthermore, the integrated automatic reclosing device is also equipped with a large-capacity memory and an anti-power fluctuation module, which are used to record 32 historical events. The large-capacity memory and the anti-power fluctuation module do not lose data when power is lost.

[0014] Furthermore, the integrated automatic reclosing device is also equipped with an RS-485 communication bus interface, which conforms to the Modbus protocol, for interfacing with the SCU and uploading the device's own event log information through the SCU, thereby improving the stability and reliability of the system.

[0015] Furthermore, the controller is encapsulated in a housing with a terminal block and a display screen. The display screen is used to display system information, and the terminal block is used to connect the closing circuit, the tripping circuit, the current circuit, and the voltage circuit.

[0016] Furthermore, the integrated automatic reclosing device can be installed on existing circuit breakers to control the closing and tripping of the circuit breaker; it is fixed by opening a rectangular mounting hole on the outer cabinet door of the circuit breaker incoming line cabinet.

[0017] The beneficial effects achieved by this utility model are:

[0018] The integrated reclosing device proposed in this invention outputs control signals for the electric closing and electric opening of the circuit breaker, as well as control signals for various operating status indicator lights. It replaces the hierarchical operation of traditional relays, thus solving problems such as transmission jamming, contact oxidation, and adhesion inherent in traditional relays. Furthermore, the integrated reclosing device is simple and quick to operate, and offers advantages such as easy debugging and maintenance.

[0019] The integrated reclosing device proposed in this utility model has an event recording function, which can detect and record the status information and voltage data of the circuit breaker at the moment of undervoltage trip in real time, accurately judge the instantaneous fault and permanent fault of the circuit breaker, thereby achieving precise reclosing. It can automatically reclose when recoverable faults such as undervoltage occur, reduce the workload of operation and maintenance and power outages, and improve user satisfaction.

[0020] The integrated reclosing device proposed in this utility model uses PLC hardware and software to form the control system of the automatic reclosing device. The device communication interface is RS485, and the protocol is Modbus. It can be connected to SCU and upload the device's own event log information through SCU. This effectively solves the defects and shortcomings of traditional relay-type automatic reclosing and improves the stability and reliability of the system. Attached Figure Description

[0021] Figure 1 This utility model provides a circuit diagram of an integrated automatic reclosing device;

[0022] Figure 2 This utility model provides a schematic diagram of the voltage circuit in an integrated automatic reclosing device;

[0023] Figure 3 This utility model provides a schematic diagram of the closing circuit and the tripping circuit in an integrated automatic reclosing device;

[0024] Figure 4 A schematic diagram of the wiring board in an integrated automatic reclosing device provided by this utility model;

[0025] Figure 5 This utility model provides an installation diagram of an integrated automatic reclosing device in a circuit breaker box. Detailed Implementation

[0026] The technical solution of this utility model will be described in more detail below with reference to the accompanying drawings. This utility model includes, but is not limited to, the following embodiments.

[0027] To better understand the above-mentioned objectives, features and advantages of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] Example 1

[0029] like Figure 1 As shown, this utility model proposes an integrated automatic reclosing device, which includes a controller, a closing circuit, a tripping circuit, a current circuit, and a voltage circuit.

[0030] The controller uses a Mitsubishi FX3U-32MR PLC, which outputs closing and tripping signals. The controller is encapsulated in a housing with a terminal block and a display screen. The display screen is used to show system information, and the terminal block is used to connect the closing circuit, tripping circuit, current circuit, voltage circuit, and other control or indicating circuits.

[0031] The closing circuit is connected between the live wire and the neutral wire, and includes a closing air switch, a closing relay, and a closing coil. The closing relay, the closing air switch, and the closing coil are connected to the neutral wire by a single-phase live wire in sequence. The two ends of the closing relay are connected to the controller to obtain the closing signal. The closing air switch is a normally closed switch. The closing coil is matched with the closing relay to perform the closing operation.

[0032] The trip circuit includes a trip air switch, a trip relay, and a trip coil; wherein, the trip relay, the trip air switch, and the trip coil are connected sequentially to the neutral wire by a single-phase live wire; the two ends of the trip relay are connected to the controller to obtain the trip signal; the trip air switch is a normally open switch; the trip coil is matched with the trip relay to perform the trip operation.

[0033] The current loop includes a three-phase current transformer and a zero-sequence current transformer. The three-phase current transformer is used to detect whether the current in the three-phase busbar exceeds the normal operating range; the zero-sequence current transformer is used to detect whether the three-phase circuit is balanced. The current loop transmits the detection results to the controller, which serves as the basis for the controller to output closing and tripping signals.

[0034] The voltage circuits are connected to the three-phase power supply on the high-voltage side of the circuit breaker to detect whether there is voltage on the high-voltage side of the circuit breaker in real time, which serves as the basis for the controller to output closing and tripping signals.

[0035] like Figure 2 As shown, the voltage loop includes three single-phase detection circuits. Each single-phase detection circuit includes optocoupler isolation, resistors R1, R2, R3, R4, R5, R6, and capacitor C6.

[0036] The optocoupler isolation uses a single-channel 220V AC optocoupler module manufactured by JIAQISHENG JOS, including a live wire interface, a neutral wire interface, a power supply interface, a signal output interface, and a grounding interface. The single-phase voltage input terminal, resistors R1, R2, and R3 are connected in series and input to the optocoupler live wire interface. The neutral wire interface is connected to the neutral wire through resistor R4. Resistor R5 is connected in parallel with the optocoupler power supply interface and the signal output interface. The optocoupler power supply interface is connected to the power supply, and the signal output interface is connected to the controller input terminal. One end of capacitor C6 and resistor R6 is connected to the optocoupler signal output interface, and the other end of capacitor C6 and resistor R6 is grounded.

[0037] The integrated automatic reclosing device is also equipped with an event recording module, which can detect and record the status information and voltage data of the circuit breaker at the moment of undervoltage trip in real time, accurately judge the instantaneous fault and permanent fault of the circuit breaker, thereby achieving precise reclosing. It can automatically reclose when recoverable faults such as undervoltage occur to prevent accidental power supply.

[0038] The integrated automatic reclosing device is also equipped with a large-capacity memory and an anti-power fluctuation module, ensuring that 32 historical events are recorded and that the data is not lost when power is lost.

[0039] This integrated automatic reclosing device is also equipped with an RS-485 communication bus interface, which conforms to the Modbus protocol. It can interface with the SCU and upload the device's own event log information through the SCU, effectively solving the defects and shortcomings of traditional relay-type automatic reclosing and improving the stability and reliability of the system.

[0040] Example 2

[0041] like Figure 3 As shown, in this embodiment, the closing signal and tripping signal output by the controller are used to switch and control the closing coil and the opening coil respectively by means of miniature relays KA1 and KA2, so as to realize the closing and opening operation of the line circuit breaker.

[0042] The controller first activates the reclosing device; otherwise, this function is self-locked. Then, during manual closing, it checks for overcurrent in the line. If overcurrent occurs, the circuit breaker should trip instantly, disconnecting the line. If no overcurrent occurs, closing is successful. After successful manual closing, the line operates under normal conditions for a period of time, i.e., in the fully charged state. If the circuit breaker trips due to overcurrent protection, the controller activates the reclosing device, sending a closing signal to close the circuit breaker once. After reclosing, it checks whether the overcurrent condition persists, i.e., determines if it is a fault.

[0043] If the fault is permanent, the circuit breaker will trip again, and the reclosing device will not initiate the reclosing operation. If the fault is transient, the circuit breaker will close successfully, and the controller's internal timer will begin simulating charging time to prepare for the next reclosing attempt and will mark the reclosing action.

[0044] Example 3

[0045] like Figure 4 As shown, in this embodiment, the terminal block includes interfaces A01-A13 and B1-B20. Interfaces A01-A03 are used for bus power input; A04-A05 are used for communication; A06-A07 are used to connect to the trip circuit; A08-A09 are used to connect to the closing circuit; A10-A11 are used to connect to the trip signal; and A12-A13 are used to connect to the alarm signal. Interfaces B01-B08 are used to connect to the current loop; B09-B11 are used to connect to the voltage loop; B12 is used to connect to the circuit breaker position signal; B13 is used to connect to the lockout power-on closing signal; B14 is used to connect to the spring uncharged signal; and B20 is used to input 24V power. The remaining interfaces are for backup.

[0046] Specifically, A06 and A07 need to be connected to the tripping circuit; A08 and A09 need to be connected to the closing circuit for fault-free closing upon power restoration. B09, B10, and B11 are connected to the voltage circuit respectively. B01 to B06 are paired up and connected to both ends of the three-phase current transformer in the current circuit respectively; B07 and B08 are connected to both ends of the zero-sequence current transformer in the current circuit respectively. Whether to connect them to the device can be determined according to the usage requirements. B20 is the 24V positive terminal, B12 is the circuit breaker position, and B13 is the circuit breaker fault output contact, used to block power restoration closing. Whether to connect them to the device can be determined according to the usage requirements.

[0047] Example 4

[0048] like Figure 5 As shown in this embodiment, the integrated automatic reclosing device proposed by this utility model can be directly installed in the residential power distribution room and connected to the existing circuit breaker to control the closing and tripping of the circuit breaker.

[0049] The integrated automatic reclosing device is installed on the outer cabinet door of the circuit breaker incoming line cabinet. A rectangular mounting hole needs to be drilled in the outer cabinet door, and the contacts of the current transformer and the three-phase incoming voltage of the circuit breaker's incoming busbar are connected to the corresponding interface of the integrated reclosing device. One phase voltage of the circuit breaker's incoming busbar is connected to interface A02, and the neutral wire of the circuit breaker's neutral busbar is connected to interface A03. Terminals A06 and A07 of the integrated reclosing device are trip control interfaces, and terminals A08 and A09 are closing control interfaces. Therefore, A08 and A09 need to be connected to the closing circuit of the circuit breaker protection controller for fault-free closing upon power restoration.

[0050] When maintenance is required, maintenance personnel only need to short-circuit the B13 terminal and the B20 terminal of the integrated reclosing device to lock the reclosing device and disconnect it from the circuit breaker.

[0051] This utility model is not limited to the specific embodiments described above. Those skilled in the art can implement this utility model using other specific embodiments based on the disclosed content of the embodiments and drawings. Therefore, any design that adopts the design structure and concept of this utility model and makes some simple changes or modifications falls within the protection scope of this utility model.

Claims

1. An integrated automatic reclosing device for controlling a circuit breaker to reclose, characterized in that, The integrated automatic reclosing device includes a controller, a closing circuit, a tripping circuit, a current circuit, and a voltage circuit; The controller is connected to the current loop and the voltage loop respectively, and is used to obtain the circuit breaker status; The controller is connected to the closing circuit and the tripping circuit respectively, and is used to output closing signals and tripping signals; The closing circuit is connected between the live wire and the neutral wire, and includes a closing air switch, a closing relay, and a closing coil; the closing relay, the closing air switch, and the closing coil are connected in series between the single-phase live wire and the neutral wire; the two ends of the closing relay are connected to the controller to obtain the closing signal; the closing air switch is a normally closed switch; the closing coil is matched with the circuit breaker, and when the closing coil is energized, the circuit breaker closes. The tripping circuit is connected between the live wire and the neutral wire, and includes a tripping air switch, a tripping relay, and a tripping coil; the tripping relay, the tripping air switch, and the tripping coil are connected to the neutral wire in sequence by a single-phase live wire; the two ends of the tripping relay are connected to the controller to obtain the tripping signal; the tripping air switch is a normally open switch; the tripping coil is matched with the tripping relay to perform the tripping operation; The current loop includes a three-phase current transformer and a zero-sequence current transformer. The three-phase current transformers are located on the incoming side of the circuit breaker and consist of three transformers: phase A, phase B, and phase C. The phase A, phase B, and phase C transformers respectively detect whether the current in the three-phase busbars exceeds the normal operating range. The zero-sequence current transformer is located on the incoming side of the circuit breaker, and all three phase busbars pass through the coil of the zero-sequence current transformer. The coil of the zero-sequence current transformer is used to detect whether the three-phase circuit is balanced. The current loop is connected to a controller to transmit the current detection results. The voltage circuit includes three single-phase detection circuits. Each single-phase detection circuit includes an optocoupler, resistors R1, R2, R3, R4, R5, and R6, and capacitor C6. The optocoupler includes a live wire interface, a neutral wire interface, a power supply interface, a signal output interface, and a ground interface. The single-phase voltage input terminal, resistors R1, R2, and R3 are connected in series and input to the optocoupler live wire interface. The neutral wire interface is connected to the neutral wire through resistor R4. Resistor R5 is connected in parallel with the optocoupler power supply interface and the signal output interface. The optocoupler power supply interface is connected to the power supply, and the signal output interface is connected to the controller input terminal. One end of capacitor C6 and resistor R6 is connected to the optocoupler signal output interface, and the other end of capacitor C6 and resistor R6 is grounded.

2. The integrated automatic reclosing device according to claim 1, characterized in that, The integrated automatic reclosing device is also equipped with an event recording module, which can detect and record the status information and voltage data of the circuit breaker at the moment of undervoltage trip in real time, and judge the instantaneous fault and permanent fault of the circuit breaker, thereby achieving accurate reclosing and preventing accidental power supply.

3. The integrated automatic reclosing device according to claim 1, characterized in that, The integrated automatic reclosing device is also equipped with a large-capacity memory and an anti-power fluctuation module, which are used to record 32 historical events. The large-capacity memory and the anti-power fluctuation module do not lose data when power is lost.

4. The integrated automatic reclosing device according to claim 1, characterized in that, The integrated automatic reclosing device is also equipped with an RS-485 communication bus interface, which conforms to the Modbus protocol, for interfacing with the SCU. The device uploads its own event log information through the SCU, thereby improving the stability and reliability of the system.

5. The integrated automatic reclosing device according to claim 1, characterized in that, The controller is encapsulated in a housing with a terminal block and a display screen. The display screen is used to display system information, and the terminal block is used to connect the closing circuit, tripping circuit, current circuit, and voltage circuit.

6. The integrated automatic reclosing device according to claim 5, characterized in that, The integrated automatic reclosing device can be installed on existing circuit breakers to control the closing and tripping of the circuit breakers; it is fixed by opening a rectangular mounting hole on the outer cabinet door of the circuit breaker incoming line cabinet.

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