Dual-power switching system based on low-voltage power supply circuit breaker

Abstract

The utility model discloses a dual-power switching system based on a low-voltage power supply circuit breaker, which relates to the field of circuit breaker control and comprises a main loop, a first control loop and a second control loop, the main loop comprises a working power supply, a standby power supply, a direct-current power supply, a first circuit breaker, a second circuit breaker and a voltage monitoring device; the first control loop comprises a first air switch, a first connecting pressure plate and a second connecting pressure plate; the second control loop comprises a second air switch, a third connecting pressure plate and a fourth connecting pressure plate; the working power supply and the standby power supply are respectively connected with the target bus through corresponding incoming lines; a first circuit breaker is arranged on an inlet wire, connected with the target bus, of the working power supply; a second circuit breaker is arranged on an incoming line, connected with the target bus, of the standby power supply; the voltage monitoring device is connected with an incoming line of the working power supply, an incoming line of the standby power supply and the DC power supply. According to the invention, automatic switching between the working power supply and the standby power supply is realized.

Description

Technical Field

[0001] This application relates to the field of circuit breaker control technology, and in particular to a dual power supply switching system based on a low-voltage power supply circuit breaker. Background Technology

[0002] In existing industrial control processes, 380V busbars typically employ a dual power supply system. The purpose of this system is to ensure that the backup power supply can continue to supply power to the busbar when the working power supply fails, thereby guaranteeing the normal operation of industrial control.

[0003] Currently, the switching between the working power supply and the backup power supply is mostly handled manually. For example, if the working power supply suddenly fails during equipment operation, the operator needs to press the working power supply trip button to reconnect the working power supply's tripping circuit, and then press the backup power supply closing button to reconnect the backup power supply's closing circuit, manually switching the working power supply to the backup power supply. When the working power supply returns to normal, the operator presses the backup power supply trip button to reconnect the backup power supply's tripping circuit, and then presses the working power supply closing button to reconnect the working power supply's closing circuit, manually switching the backup power supply back to the working power supply. Because manual operation always involves an operation time, this results in a relatively long power outage time for the busbar during the above process, and it cannot achieve uninterrupted continuous power supply. Summary of the Invention

[0004] The purpose of this application is to provide a dual power supply switching system based on a low-voltage power supply circuit breaker, which realizes automatic switching between the working power supply and the backup power supply, and can ensure uninterrupted power supply to the bus.

[0005] To achieve the above objectives, this application provides the following solution:

[0006] This application provides a dual power supply switching system based on a low-voltage power supply circuit breaker. The dual power supply switching system based on a low-voltage power supply circuit breaker includes: a main circuit, a first control circuit, and a second control circuit; the main circuit includes: a working power supply, a backup power supply, a DC power supply, a first circuit breaker, a second circuit breaker, and a voltage monitoring device; the first control circuit includes: a first air switch, a first connecting plate, and a second connecting plate; the second control circuit includes: a second air switch, a third connecting plate, and a fourth connecting plate.

[0007] The working power supply and the backup power supply are respectively connected to the target bus via corresponding incoming lines; a first circuit breaker is installed on the incoming line connecting the working power supply and the target bus; a second circuit breaker is installed on the incoming line connecting the backup power supply and the target bus; the voltage monitoring device is connected to the incoming line of the working power supply, the incoming line of the backup power supply, and the DC power supply respectively.

[0008] The first contact of the first air switch and the first contact of the second air switch are respectively connected to the positive terminal of the DC power supply; the third contact of the first air switch and the third contact of the second air switch are respectively connected to the negative terminal of the DC power supply.

[0009] The second contact of the first air switch, the first connecting pressure plate, the first auxiliary contact of the voltage monitoring device, the second normally closed contact of the second circuit breaker, the second normally closed contact of the first circuit breaker, the closing coil of the first circuit breaker, and the fourth contact of the first air switch are connected in series in sequence; the second contact of the first air switch, the second connecting pressure plate, the second auxiliary contact of the voltage monitoring device, the second normally open contact of the first circuit breaker, the opening coil of the first circuit breaker, and the fourth contact of the first air switch are connected in series in sequence; the third auxiliary contact of the voltage monitoring device is connected in parallel with the second auxiliary contact of the voltage monitoring device.

[0010] The second contact of the second air switch, the third connecting plate, the fourth auxiliary contact of the voltage monitoring device, the second normally closed contact of the first circuit breaker, the second normally closed contact of the second circuit breaker, the closing coil of the second circuit breaker, and the fourth contact of the second air switch are connected in series in sequence; the second contact of the second air switch, the fourth connecting plate, the fifth auxiliary contact of the voltage monitoring device, the second normally open contact of the second circuit breaker, the opening coil of the second circuit breaker, and the fourth contact of the second air switch are connected in series in sequence; the sixth auxiliary contact of the voltage monitoring device is connected in parallel with the fifth auxiliary contact of the voltage monitoring device.

[0011] Optionally, a third circuit breaker is provided on the connection line between the voltage monitoring device and the incoming line of the working power supply; a fourth circuit breaker is provided on the connection line between the voltage monitoring device and the incoming line of the backup power supply; and a fifth circuit breaker is provided on the connection line between the voltage monitoring device and the DC power supply.

[0012] Optionally, the first control loop further includes: a first indicator light, a second indicator light, and a third indicator light;

[0013] One end of the first indicator light is connected to the first normally closed contact of the first circuit breaker; one end of the second indicator light is connected to the first normally open contact of the first circuit breaker; one end of the third indicator light is connected to the second contact of the first air switch; the other ends of the first indicator light, the second indicator light, and the third indicator light are all connected to the fourth contact of the first air switch.

[0014] Optionally, the second contact of the first air switch is connected to the first normally closed contact and the first normally open contact of the first circuit breaker, respectively.

[0015] Optionally, the first control circuit further includes: a first closing button and a first opening button;

[0016] One end of the first closing button and one end of the first opening button are respectively connected to the second contact of the first air switch; the other end of the first closing button is connected to the second normally closed contact of the second circuit breaker; and the other end of the first opening button is connected to the second normally open contact of the first circuit breaker.

[0017] Optionally, the second control loop further includes: a fourth indicator light, a fifth indicator light, and a sixth indicator light;

[0018] One end of the fourth indicator light is connected to the first normally closed contact of the second circuit breaker; one end of the fifth indicator light is connected to the first normally open contact of the second circuit breaker; one end of the sixth indicator light is connected to the second contact of the second air switch; the other ends of the fourth indicator light, the fifth indicator light, and the sixth indicator light are all connected to the fourth contact of the second air switch.

[0019] Optionally, the second contact of the second air switch is connected to the first normally closed contact and the first normally open contact of the second circuit breaker, respectively.

[0020] Optionally, the second control circuit further includes: a second closing button and a second opening button;

[0021] One end of the second closing button and one end of the second opening button are respectively connected to the second contact of the second air switch; the other end of the second closing button is connected to the second normally closed contact of the first circuit breaker; and the other end of the second opening button is connected to the second normally open contact of the second circuit breaker.

[0022] Optionally, the target busbar is a 380V busbar.

[0023] Optionally, the DC power supply is a 220V power supply.

[0024] According to the specific embodiments provided in this application, the following technical effects are disclosed:

[0025] The voltage monitoring device in this application can monitor the energization of the incoming lines of both the working power supply and the backup power supply. When both the working power supply and the backup power supply are detected to be energized simultaneously, the first and fifth auxiliary contacts of the voltage monitoring device close. At this time, the closing coil of the first circuit breaker is energized, while the closing coil of the second circuit breaker is de-energized, and only the working power supply supplies power to the target bus. When the working power supply is detected to be de-energized, the second and fourth auxiliary contacts of the voltage monitoring device close. At this time, the opening coil of the first circuit breaker is energized, and the closing coil of the second circuit breaker is energized, and only the backup power supply supplies power to the target bus. Based on the connection relationship between and within the main circuit, the first control circuit, and the second control circuit in this application, the voltage monitoring device can automatically switch the power supply to the target bus according to the energization status of the incoming lines, ensuring uninterrupted power supply to the bus from different power sources, while preventing the working power supply and the backup power supply from supplying power simultaneously. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 A connection diagram of the main circuit provided in the embodiments of this application;

[0028] Figure 2 A connection diagram of the first control circuit and the second control circuit provided in the embodiments of this application.

[0029] Symbol explanation:

[0030] First circuit breaker—QF1, closing coil of the first circuit breaker—QF1-HZ, opening coil of the first circuit breaker—QF1-TZ, first normally open contact of the first circuit breaker—QF1-NO1, second normally open contact of the first circuit breaker—QF1-NO2, first normally closed contact of the first circuit breaker—QF1-NC1, second normally closed contact of the first circuit breaker—QF1-NC2, second circuit breaker—QF2, closing coil of the second circuit breaker—QF2-HZ, opening coil of the second circuit breaker—QF2-TZ, first normally open contact of the second circuit breaker—QF2-NO1, second normally open contact of the second circuit breaker—QF2-NO2, first normally closed contact of the second circuit breaker—QF2-NC1, second normally closed contact of the second circuit breaker—QF2- NC2, Third Circuit Breaker—QF3, Fourth Circuit Breaker—QF4, Fifth Circuit Breaker—QF5, First Air Switch—DK1, Second Air Switch—DK2, First Connecting Plate—LP1, Second Connecting Plate—LP2, Third Connecting Plate—LP3, Fourth Connecting Plate—LP4, First Auxiliary Contact of Voltage Monitoring Device—K1, Second Auxiliary Contact of Voltage Monitoring Device—K2, Third Auxiliary Contact of Voltage Monitoring Device—K3, Fourth Auxiliary Contact of Voltage Monitoring Device—K4, Fifth Auxiliary Contact of Voltage Monitoring Device—K5, Sixth Auxiliary Contact of Voltage Monitoring Device—K6, First Indicator Light—L1, Second Indicator Light—L2, Third Indicator Light—L3, Fourth Indicator Light—L4, Fifth Indicator Light—L5, Sixth Indicator Light—L6. Detailed Implementation

[0031] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0032] The purpose of this application is to provide a dual power supply switching system based on a low-voltage power supply circuit breaker, which realizes automatic switching between the working power supply and the backup power supply, and can ensure uninterrupted power supply to the bus.

[0033] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] like Figure 1 and Figure 2As shown, this embodiment provides a dual power supply switching system based on a low-voltage power supply circuit breaker. The dual power supply switching system based on a low-voltage power supply circuit breaker includes: a main circuit, a first control circuit, and a second control circuit; the main circuit includes: a working power supply, a backup power supply, a DC power supply, a first circuit breaker QF1, a second circuit breaker QF2, and a voltage monitoring device; the first control circuit includes: a first air switch DK1, a first connecting plate LP1, and a second connecting plate LP2; the second control circuit includes: a second air switch DK2, a third connecting plate LP3, and a fourth connecting plate LP4.

[0035] In the main circuit, the working power supply and the backup power supply are respectively connected to the target bus (380V bus in this embodiment) through corresponding incoming lines; a first circuit breaker QF1 is installed on the incoming line connecting the working power supply and the target bus; a second circuit breaker QF2 is installed on the incoming line connecting the backup power supply and the target bus; the voltage monitoring device is connected to the incoming line of the working power supply, the incoming line of the backup power supply and the DC power supply (220V power supply in this embodiment) respectively. A third circuit breaker QF3 is installed on the connection line between the voltage monitoring device and the incoming line of the working power supply. The UA1, UB1, and UC1 terminals of the voltage monitoring device are connected to the three contacts of the third circuit breaker QF3, and the other three contacts of the third circuit breaker QF3 are connected to the three-phase incoming line of the working power supply. The UN1 terminal of the voltage monitoring device is connected to the neutral line. A fourth circuit breaker QF4 is installed on the connection line between the voltage monitoring device and the incoming line of the backup power supply. The UA2, UB2, and UC2 terminals of the voltage monitoring device are connected to the three contacts of the fourth circuit breaker QF4, and the other three contacts of the fourth circuit breaker QF4 are connected to the three-phase incoming line of the backup power supply. The UN2 terminal of the voltage monitoring device is connected to the neutral line. A fifth circuit breaker QF5 is installed on the connection line between the voltage monitoring device and the DC power supply. The positive terminal L+ and the negative terminal L- of the power supply of the voltage monitoring device are connected to the two contacts of the fifth circuit breaker QF5, and the other two contacts of the fifth circuit breaker QF5 are connected to the positive and negative terminals of the DC power supply, respectively.

[0036] In the first control circuit, the first contact of the first air switch DK1 is connected to the positive terminal of the DC power supply, and the third contact of the first air switch DK1 is connected to the negative terminal of the DC power supply; the second contact of the first air switch DK1, the first connecting plate LP1, the first auxiliary contact K1 of the voltage monitoring device, the second normally closed contact QF2-NC2 of the second circuit breaker, the second normally closed contact QF1-NC2 of the first circuit breaker, the closing coil QF1-HZ of the first circuit breaker, and the fourth contact of the first air switch DK1 are connected in series in sequence; the second contact of the first air switch DK1, the second connecting plate LP2, the second auxiliary contact K2 of the voltage monitoring device, the second normally open contact QF1-NO2 of the first circuit breaker, the opening coil QF1-TZ of the first circuit breaker, and the fourth contact of the first air switch DK1 are connected in series in sequence; the third auxiliary contact K3 of the voltage monitoring device is connected in parallel with the second auxiliary contact K2 of the voltage monitoring device.

[0037] Furthermore, the first control circuit also includes: a first indicator light L1, a second indicator light L2, and a third indicator light L3; one end of the first indicator light L1 is connected to the first normally closed contact QF1-NC1 of the first circuit breaker; one end of the second indicator light L2 is connected to the first normally open contact QF1-NO1 of the first circuit breaker; one end of the third indicator light L3 is connected to the second contact of the first air switch DK1; the other ends of the first indicator light L1, the second indicator light L2, and the third indicator light L3 are all connected to the fourth contact of the first air switch DK1; the second contact of the first air switch DK1 is connected to the first normally closed contact QF1-NC1 and the first normally open contact QF1-NO1 of the first circuit breaker, respectively.

[0038] Furthermore, the first control circuit also includes: a first closing button SBH1 and a first opening button SBT1; one end of the first closing button SBH1 and one end of the first opening button SBT1 are respectively connected to the second contact of the first air switch DK1; the other end of the first closing button SBH1 is connected to the second normally closed contact QF2-NC2 of the second circuit breaker; the other end of the first opening button SBT1 is connected to the second normally open contact QF1-NO2 of the first circuit breaker.

[0039] In the second control circuit, the first contact of the second air switch DK2 is connected to the positive terminal of the DC power supply; the third contact of the second air switch DK2 is connected to the negative terminal of the DC power supply; the second contact of the second air switch DK2, the third connecting plate LP3, the fourth auxiliary contact K4 of the voltage monitoring device, the second normally closed contact QF1-NC2 of the first circuit breaker, the second normally closed contact QF2-NC2 of the second circuit breaker, the closing coil QF2-HZ of the second circuit breaker, and the fourth contact of the second air switch DK2 are connected in series in sequence; the second contact of the second air switch DK2, the fourth connecting plate LP4, the fifth auxiliary contact K5 of the voltage monitoring device, the second normally open contact QF2-NO2 of the second circuit breaker, the opening coil QF2-TZ of the second circuit breaker, and the fourth contact of the second air switch DK2 are connected in series in sequence; the sixth auxiliary contact K6 of the voltage monitoring device is connected in parallel with the fifth auxiliary contact K5 of the voltage monitoring device.

[0040] Furthermore, the second control circuit also includes: a fourth indicator light L4, a fifth indicator light L5, and a sixth indicator light L6; one end of the fourth indicator light L4 is connected to the first normally closed contact QF2-NC1 of the second circuit breaker; one end of the fifth indicator light L5 is connected to the first normally open contact QF2-NO1 of the second circuit breaker; one end of the sixth indicator light L6 is connected to the second contact of the second air switch DK2; the other ends of the fourth indicator light L4, the fifth indicator light L5, and the sixth indicator light L6 are all connected to the fourth contact of the second air switch DK2; the second contact of the second air switch DK2 is connected to the first normally closed contact QF2-NC1 of the second circuit breaker and the first normally open contact QF2-NO1 of the second circuit breaker, respectively.

[0041] Furthermore, the second control circuit also includes: a second closing button SBH2 and a second opening button SBT2; one end of the second closing button SBH2 and one end of the second opening button SBT2 are respectively connected to the second contact of the second air switch DK2; the other end of the second closing button SBH2 is connected to the second normally closed contact QF1-NC2 of the first circuit breaker; and the other end of the second opening button SBT2 is connected to the second normally open contact QF2-NO2 of the second circuit breaker.

[0042] To better utilize the aforementioned dual power supply switching system based on low-voltage circuit breakers, its working principle and usage are explained in detail below:

[0043] In the initial state, both circuit breakers QF1 and QF2 in the main circuit are open, and the main circuit is not energized. Simultaneously, circuit breakers QF1 and QF2 must not be closed to supply power to the 380V line, because the working power supply and backup power supply belong to two different power supply systems, and it is strictly forbidden to simultaneously connect the two power supplies. In the control circuit, closing the first air switch DK1 illuminates the third indicator light L3, indicating that the first control circuit is energized; closing the second air switch DK2 illuminates the sixth indicator light L6, indicating that the second control circuit is energized. Conversely, if the third indicator light L3 or the sixth indicator light L6 is off, the corresponding air switch may have tripped or the corresponding control circuit may have experienced an open circuit fault.

[0044] When the first circuit breaker QF1 is open, its corresponding first normally open contact QF1-NO1 opens, its first normally closed contact QF1-NC1 closes, and the first indicator light L1 illuminates, thus indicating to the operator that the first circuit breaker QF1 is in the open state; when the first circuit breaker QF1 is closed, its corresponding first normally open contact QF1-NO1 closes, its first normally closed contact QF1-NC1 opens, and the second indicator light L2 illuminates, thus indicating to the operator that the first circuit breaker QF1 is in the closed state. Similarly, when the second circuit breaker QF2 is open, its corresponding first normally open contact QF2-NO1 opens, its first normally closed contact QF2-NC1 closes, and the fourth indicator light L4 illuminates, thus indicating to the operator that the second circuit breaker QF2 is in the open state; when the second circuit breaker QF2 is closed, its corresponding first normally closed contact QF2-NC1 closes, its first normally closed contact QF2-NC1 opens, and the fifth indicator light L5 illuminates, thus indicating to the operator that the second circuit breaker QF2 is in the closed state.

[0045] The closing and opening buttons are designed to facilitate manual switching of the dual power supply in emergencies. When the first closing button SBH1 is pressed, the second normally closed contact QF2-NC2 of the second circuit breaker connected to it closes, and the second normally closed contact QF1-NC2 of the first circuit breaker also closes. This energizes the closing coil QF1-HZ of the first circuit breaker, closing the main circuit and supplying voltage to the 380V bus. After the first circuit breaker QF1 closes, the second normally closed contact QF1-NC2 of the first circuit breaker, connected to the second normally closed contact QF2-NC2 of the second circuit breaker, changes from closed to open. This prevents the closing coil QF1-HZ from burning out due to prolonged energization caused by pressing the first closing button SBH1 for too long. When the first circuit breaker QF1 closes, the second normally open contact QF1-NO2 of the first circuit breaker, which is connected in series with the first circuit breaker's tripping coil QF1-TZ, will change from the open state to the closed state. In case of an emergency requiring power outage, the first tripping button SBT1 can be pressed, energizing the first circuit breaker's tripping coil QF1-TZ and causing the first circuit breaker QF1 to open. When the first circuit breaker QF1 closes, the second normally closed contact QF1-NC2 of the first circuit breaker, which is connected in series with the second closing button SBH2, will change from the closed state to the open state to prevent accidental pressing of the second closing button SBH2 from energizing the second circuit breaker's closing coil QF2-HZ, thus preventing the second circuit breaker QF2 from closing (as stated above, it is strictly forbidden for the working power supply and standby power supply to simultaneously energize the 380V bus).

[0046] When switching the operating power supply to the backup power supply for the 380V bus, pressing the second closing button SBH2 closes the circuit. At this time, because the second normally closed contact QF1-NC2 of the first circuit breaker and the second normally closed contact QF2-NC2 of the second circuit breaker are both closed, the closing coil QF2-HZ of the second circuit breaker is energized. The second circuit breaker QF2 in the main circuit closes, and the backup power supply delivers voltage to the 380V bus. After the second circuit breaker QF2 closes, the second normally closed contact QF2-NC2 of the second circuit breaker, which is connected to the second normally closed contact QF1-NC2 of the first circuit breaker, changes from a closed state to an open state. This prevents the closing coil QF2-HZ of the second circuit breaker from burning out due to prolonged energization caused by pressing the second closing button SBH2. When the second circuit breaker QF2 closes, the second normally open contact QF2-NO2 of the second circuit breaker, which is connected in series with the trip coil QF2-TZ of the second circuit breaker, will change from the open state to the closed state. In case of an emergency requiring power outage, the second trip button SBT2 can be pressed, energizing the trip coil QF2-TZ of the second circuit breaker and causing the second circuit breaker QF2 to open. When the second circuit breaker QF2 closes, the second normally closed contact QF2-NC2 of the second circuit breaker, which is connected in series with the first closing button SBH1, will change from the closed state to the open state to prevent accidental pressing of the first closing button SBH1 from energizing the first circuit breaker's closing coil QF1-HZ, thus causing the first circuit breaker QF1 to close (as stated above, it is strictly forbidden for the working power supply and the backup power supply to simultaneously energize the 380V bus).

[0047] The effect of adding a voltage monitoring device to the main circuit:

[0048] When the fifth circuit breaker QF5 is closed, the voltage monitoring device is powered on and begins to work; when the third circuit breaker QF3 is closed, the voltage of the working power supply is sent to the voltage monitoring device, and the voltage monitoring device begins to collect the voltage of the corresponding incoming line; when the fourth circuit breaker QF4 is closed, the voltage of the backup power supply is sent to the voltage monitoring device, and the voltage monitoring device begins to collect the voltage of the corresponding incoming line.

[0049] When both the working power supply and the backup power supply are energized, the voltage monitoring device detects normal operation and closes its corresponding first auxiliary contact K1 and fifth auxiliary contact K5. At this time, the closing coil QF1-HZ of the first circuit breaker is energized, the first circuit breaker QF1 in the main circuit closes, and the second circuit breaker QF2 opens, allowing the working power supply to power the 380V busbar. When the working power supply's incoming line loses power, the voltage monitoring device detects this loss of power, closes its second auxiliary contact K2, and connects its fourth auxiliary contact K4. At this time, the first circuit breaker QF1 in the main circuit opens, and the second circuit breaker QF2 closes, allowing the backup power supply to power the 380V busbar. This ensures that the load connected to the 380V busbar will not be de-energized. When the incoming line of the working power supply is re-energized, the first auxiliary contact K1 and the fifth auxiliary contact K5 of the voltage monitoring device close, the closing coil QF1-HZ of the first circuit breaker is energized, and the opening coil QF2-TZ of the second circuit breaker is energized. The first circuit breaker QF1 in the main circuit closes, and the second circuit breaker QF2 opens, allowing the working power supply to power the 380V busbar. When the working power supply and the backup power supply fail simultaneously, the third auxiliary contact K3 and the sixth auxiliary contact K6 of the voltage monitoring device close, and both the first circuit breaker QF1 and the second circuit breaker QF2 in the main circuit are in the open state, causing the 380V busbar to lose power.

[0050] The second normally closed contact QF2-NC2 of the second circuit breaker is connected in series in the closing coil QF1-HZ circuit of the first circuit breaker, and the second normally closed contact QF1-NC2 of the first circuit breaker is connected in series in the closing coil QF2-HZ circuit of the second circuit breaker. This is to achieve interlocking between the two circuit breakers, ensuring that the closing circuits of the two circuit breakers cannot be energized simultaneously, and that the two circuit breakers cannot close simultaneously, thus ensuring that the working power supply and the backup power supply cannot simultaneously supply power to the 380V busbar. Furthermore, when the first connecting plate LP1, the second connecting plate LP2, the third connecting plate LP3, and the fourth connecting plate LP4 are engaged, the corresponding functions are effective; when these plates are disengaged, the corresponding functions are ineffective.

[0051] The main technical effects of this application are as follows:

[0052] With two independent power supplies, automatic switching between them is possible, avoiding the prolonged 380V busbar outages caused by manual switching. Furthermore, this application uses fewer physical wiring connections to smoothly complete the automatic switching between the two independent power supplies, preventing power outages to the loads supplied by the downstream busbar. The entire system improves automation levels, saves manpower, and achieves fully automatic control.

[0053] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0054] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A dual-power switching system based on a low-voltage circuit breaker, characterized in that, The dual power supply switching system based on a low-voltage power supply circuit breaker includes: a main circuit, a first control circuit, and a second control circuit; the main circuit includes: a working power supply, a backup power supply, a DC power supply, a first circuit breaker, a second circuit breaker, and a voltage monitoring device; the first control circuit includes: a first air switch, a first connecting plate, and a second connecting plate; the second control circuit includes: a second air switch, a third connecting plate, and a fourth connecting plate. The working power supply and the backup power supply are respectively connected to the target bus via corresponding incoming lines; a first circuit breaker is installed on the incoming line connecting the working power supply and the target bus; a second circuit breaker is installed on the incoming line connecting the backup power supply and the target bus; the voltage monitoring device is connected to the incoming line of the working power supply, the incoming line of the backup power supply, and the DC power supply respectively. The first contact of the first air switch and the first contact of the second air switch are respectively connected to the positive terminal of the DC power supply; the third contact of the first air switch and the third contact of the second air switch are respectively connected to the negative terminal of the DC power supply. The second contact of the first air switch, the first connecting pressure plate, the first auxiliary contact of the voltage monitoring device, the second normally closed contact of the second circuit breaker, the second normally closed contact of the first circuit breaker, the closing coil of the first circuit breaker, and the fourth contact of the first air switch are connected in series in sequence; the second contact of the first air switch, the second connecting pressure plate, the second auxiliary contact of the voltage monitoring device, the second normally open contact of the first circuit breaker, the opening coil of the first circuit breaker, and the fourth contact of the first air switch are connected in series in sequence; the third auxiliary contact of the voltage monitoring device is connected in parallel with the second auxiliary contact of the voltage monitoring device. The second contact of the second air switch, the third connecting plate, the fourth auxiliary contact of the voltage monitoring device, the second normally closed contact of the first circuit breaker, the second normally closed contact of the second circuit breaker, the closing coil of the second circuit breaker, and the fourth contact of the second air switch are connected in series in sequence; the second contact of the second air switch, the fourth connecting plate, the fifth auxiliary contact of the voltage monitoring device, the second normally open contact of the second circuit breaker, the opening coil of the second circuit breaker, and the fourth contact of the second air switch are connected in series in sequence; the sixth auxiliary contact of the voltage monitoring device is connected in parallel with the fifth auxiliary contact of the voltage monitoring device.

2. The dual power supply switching system based on a low-voltage power supply circuit breaker according to claim 1, characterized in that, A third circuit breaker is installed on the connection line between the voltage monitoring device and the incoming line of the working power supply; a fourth circuit breaker is installed on the connection line between the voltage monitoring device and the incoming line of the backup power supply; and a fifth circuit breaker is installed on the connection line between the voltage monitoring device and the DC power supply.

3. The dual power supply switching system based on a low-voltage power supply circuit breaker according to claim 1, characterized in that, The first control loop further includes: a first indicator light, a second indicator light, and a third indicator light; One end of the first indicator light is connected to the first normally closed contact of the first circuit breaker; one end of the second indicator light is connected to the first normally open contact of the first circuit breaker; one end of the third indicator light is connected to the second contact of the first air switch; the other ends of the first indicator light, the second indicator light, and the third indicator light are all connected to the fourth contact of the first air switch.

4. The dual power supply switching system based on a low-voltage power supply circuit breaker according to claim 3, characterized in that, The second contact of the first air switch is connected to the first normally closed contact and the first normally open contact of the first circuit breaker, respectively.

5. The dual power supply switching system based on a low-voltage power supply circuit breaker according to claim 1, characterized in that, The first control circuit further includes: a first closing button and a first opening button; One end of the first closing button and one end of the first opening button are respectively connected to the second contact of the first air switch; the other end of the first closing button is connected to the second normally closed contact of the second circuit breaker; and the other end of the first opening button is connected to the second normally open contact of the first circuit breaker.

6. The dual power supply switching system based on a low-voltage power supply circuit breaker according to claim 1, characterized in that, The second control loop also includes: a fourth indicator light, a fifth indicator light, and a sixth indicator light; One end of the fourth indicator light is connected to the first normally closed contact of the second circuit breaker; one end of the fifth indicator light is connected to the first normally open contact of the second circuit breaker; one end of the sixth indicator light is connected to the second contact of the second air switch; the other ends of the fourth indicator light, the fifth indicator light, and the sixth indicator light are all connected to the fourth contact of the second air switch.

7. The dual power supply switching system based on a low-voltage power supply circuit breaker according to claim 6, characterized in that, The second contact of the second air switch is connected to the first normally closed contact and the first normally open contact of the second circuit breaker, respectively.

8. The dual power supply switching system based on a low-voltage power supply circuit breaker according to claim 1, characterized in that, The second control circuit also includes: a second closing button and a second opening button; One end of the second closing button and one end of the second opening button are respectively connected to the second contact of the second air switch; the other end of the second closing button is connected to the second normally closed contact of the first circuit breaker; and the other end of the second opening button is connected to the second normally open contact of the second circuit breaker.

9. The dual power supply switching system based on a low-voltage power supply circuit breaker according to claim 1, characterized in that, The target busbar is a 380V busbar.

10. The dual power supply switching system based on a low-voltage power supply circuit breaker according to claim 1, characterized in that, The DC power supply is a 220V power supply.

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