A protection circuit and a low-voltage power supply vehicle using the same

Abstract

The utility model provides a protection circuit and use the low voltage power supply car of this protection circuit, wherein the protection circuit includes alternating -current fuse, first electric leakage protection switch, phase sequence protector, alternating -current relay and branch line output, and the output of three firewire L1 / L2 / L3 and a zero line D1 is connected in branch line output, and each firewire is from input end respectively in proper order series connection alternating -current fuse, first electric leakage protection switch and alternating -current relay, and zero line D1 series first electric leakage protection switch, in electric leakage protection switch and alternating -current relay between L1 / L2 / L3 three firewire still respectively connected to the A end, B end and C end of phase sequence protector, and phase sequence protector still includes Ta end and Tc end, and the Ta end of phase sequence protector is connected to zero line D1 and series contactor of alternating -current relay, and the Tc end of phase sequence protector is connected to firewire L3, and still be connected with voice alarm on firewire L3 and zero line D1, and the signal end of voice alarm is connected engine start signal.

Description

Technical Field

[0001] This utility model relates to the field of modified vehicle technology, and in particular to a protection circuit and a low-voltage power supply vehicle using the protection circuit. Background Technology

[0002] In recent years, with the gradual development of the functions of residual current devices (RCDs), power supply vehicles are often only equipped with RCDs for overcurrent protection. However, in scenarios such as disaster relief, emergency repair of power grid faults, and other situations, the power environment of power supply vehicles is highly complex and the circuits carry high power. The overcurrent protection function integrated by the RCD cannot provide protection for power supply vehicles in all scenarios, and fuses are required to provide additional safety assurance.

[0003] The power supply vehicle operates with multiple branch circuits, each requiring a fuse. Because each branch carries different equipment, it's easy for one or two fuses to blow, causing a phase loss. The large size and high budget of high-power phase loss protectors further complicate fuse application.

[0004] In existing technologies, the overcurrent protection function of existing power supply vehicles relying solely on leakage current protection devices is limited in complex scenarios such as disaster relief. Leakage current protection devices cannot cope with instantaneous large current surges, while traditional fuses, although providing overcurrent protection, lack rapid response to phase loss faults. Existing high-power phase loss protection devices are bulky and expensive, making them difficult to widely adopt in the multi-branch circuits of power supply vehicles. Furthermore, the load differences in existing power supply vehicle branch circuits are large, and a single leakage current protection switch may result in a protection blind zone due to insufficient sensitivity. Utility Model Content

[0005] Therefore, the purpose of this utility model is to provide a protection circuit and a low-voltage power supply vehicle using the protection circuit, which can effectively solve the shortcomings of the prior art.

[0006] A protection circuit, comprising:

[0007] An AC fuse, a first residual current circuit breaker, a phase sequence protection device, an AC relay, and a branch line output terminal are provided. The output terminals of three live wires L1 / L2 / L3 and one neutral wire D1 are connected to the branch line output terminal. Each live wire is connected in series with the AC fuse, the first residual current circuit breaker, and the AC relay from the input terminal. The neutral wire D1 is connected in series with the first residual current circuit breaker.

[0008] The three live wires L1 / L2 / L3 between the leakage current protection switch and the AC relay are also connected to the A, B and C terminals of the phase loss sequence protector, respectively.

[0009] The phase loss sequence protector also includes a Ta terminal and a Tc terminal. The Ta terminal of the phase loss sequence protector is connected to the neutral line D1 and connected in series with the contactor of the AC relay. The Tc terminal of the phase loss sequence protector is connected to the live line L3.

[0010] A voice alarm is also connected to the live wire L3 and the neutral wire D1. The signal terminal of the voice alarm is connected to the engine start signal.

[0011] Compared with the prior art, the beneficial effects of this utility model are as follows: by connecting the AC fuse, leakage protection switch, phase sequence protection device, and AC relay in series, a multi-layer protection mechanism is formed. When the circuit experiences overcurrent, leakage, or phase loss, the power supply can be quickly cut off to avoid equipment damage and safety accidents. Specifically, the AC fuse and leakage protection switch detect whether the entire circuit is normal. When overcurrent or leakage occurs, the corresponding device quickly trips to protect the safety of the entire circuit. The phase sequence and phase loss protection device detects the three-phase power status. When the fuse causes a phase loss, it trips in a short time, causing the AC relay to act and disconnect the power supply to the circuit, avoiding equipment damage caused by phase loss. At the same time, the voice alarm is linked with the engine signal, and automatically broadcasts a warning when a fault occurs, significantly improving the warning effect in complex environments.

[0012] Furthermore, the Tc terminal of the phase loss sequence protector is specifically connected between the leakage current protection switch and the AC relay.

[0013] Furthermore, a branch circuit is connected between the Ta terminal of the phase loss sequence protector and the contactor of the AC relay. This branch circuit is connected to the neutral line D1 and connected in series with the second leakage current protection switch.

[0014] Furthermore, a self-locking single-pole double-control switch is provided between the Ta terminal of the phase loss sequence protector and the branch circuit.

[0015] Furthermore, the self-locking single-opening double-control switch is connected in series between the voice alarm and the engine start signal.

[0016] Furthermore, power indicator lights are connected to the live wire L3 and the neutral wire D1.

[0017] Furthermore, the branch line output terminal is also connected to a ground wire.

[0018] On the other hand, this utility model also provides a low-voltage power supply vehicle, including the protection circuit described above. Attached Figure Description

[0019] Figure 1 This is a circuit diagram of the protection circuit in an embodiment of the present utility model;

[0020] Explanation of key component symbols:

[0021] The following detailed description, in conjunction with the accompanying drawings, will further illustrate this utility model.

[0022] First leakage protection switch 2 Voice alarm 10 Phase sequence protection device 3 Engine start signal 11 AC relay 4 Branching 12 Branch output terminal 5 Second leakage protection switch 13 Fireline L1 6 Self-locking single-pole double-throw switch 14 Fireline L2 7 Power indicator light 15 Fireline L3 8 ground wire 16 Detailed Implementation

[0023] To facilitate understanding of this utility model, a more complete description will be given below with reference to the accompanying drawings. Several embodiments of this utility model are shown in the drawings. However, this utility model can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this utility model will be more thorough and complete.

[0024] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0026] A protection circuit, comprising:

[0027] The AC fuse 1, the first residual current circuit breaker 2, the phase sequence protection device 3, the AC relay 4, and the branch output terminal 5 are connected to the branch output terminal 5. The output terminals of the three live wires L1 / L2 / L3 and the neutral wire D1 are connected in series. Each live wire is connected in series with the AC fuse 1, the first residual current circuit breaker 2, and the AC relay 4 from the input terminal. The neutral wire D1 is connected in series with the first residual current circuit breaker 2.

[0028] The three live wires L1 / L2 / L3 between the leakage current protection switch 2 and the AC relay 4 are also connected to the A, B and C terminals of the phase sequence loss protector 3, respectively.

[0029] The phase sequence protection device 3 also includes a Ta terminal and a Tc terminal. The Ta terminal of the phase sequence protection device 3 is connected to the neutral line D1 and connected in series with the contactor of the AC relay 4. The Tc terminal of the phase sequence protection device 3 is connected to the live line L3.

[0030] A voice alarm 10 is also connected to the live wire L3 and the neutral wire D1. The signal terminal of the voice alarm 10 is connected to the engine start signal 11.

[0031] Understandably, the AC fuse 1 and the first leakage protection switch 2 are used to detect whether the entire circuit is normal. When an overcurrent or leakage occurs, the corresponding equipment will quickly trip to protect the safety of the entire circuit. The phase sequence and phase loss protector 3 detects the three-phase power status. When the fuse causes a phase loss, it will trip in a short time, causing the AC relay 4 to operate and disconnect the power supply to the circuit, thus avoiding damage to the equipment due to phase loss.

[0032] Furthermore, the Tc terminal of the phase loss sequence protector 3 is specifically connected between the leakage current protection switch 2 and the AC relay 4.

[0033] Understandably, by connecting the Tc terminal of the phase loss sequence protector 3 between the leakage current protection switch 2 and the AC relay 4, the phase loss detection signal is ensured to directly act on the control circuit of the AC relay 4, thus shortening the protection action time and improving the system response speed.

[0034] Furthermore, a branch circuit 12 is connected between the Ta terminal of the phase loss sequence protector 3 and the contactor of the AC relay 4. The branch circuit 12 is connected to the neutral line D1 and connected in series with the second leakage protection switch 13.

[0035] Understandably, by adding the branch circuit 12 and the second leakage protection switch 13 between the Ta terminal of the phase loss sequence protector 3 and the contactor of the AC relay 4, a dual leakage protection mechanism is formed. The branch circuit 12 is connected to the neutral line D1 and the second leakage protection switch 13 is connected in series to provide redundant protection, avoid leakage risk caused by the failure of a single leakage protector, and improve the fault tolerance of the system.

[0036] Furthermore, a self-locking single-pole double-control switch 14 is provided between the Ta terminal of the phase loss sequence protector 3 and the branch circuit 12.

[0037] Understandably, the design of the self-locking single-pole double-control switch 14 enables one-button control of the circuit, allowing operators to quickly start and stop the circuit. At the same time, the self-locking function prevents misoperation and enhances the convenience and safety of the system. The introduction of this switch is particularly suitable for the rapid response needs of power supply vehicles in emergency scenarios.

[0038] Furthermore, the self-locking single-opening double-control switch 14 is connected in series between the voice alarm 10 and the engine start signal 11.

[0039] Understandably, by connecting the self-locking single-pole double-control switch 14 in series between the voice alarm 10 and the engine start signal 11, the voice alarm 10 is ensured to work only when the generator is started and the circuit is energized. This design avoids false alarms and optimizes system energy consumption.

[0040] Furthermore, power indicator lights 15 are connected to the live wire L3 and the neutral wire D1.

[0041] Understandably, the power indicator light 15 is designed to visually display the circuit's operating status, facilitating real-time monitoring by operators. Combined with the voice alarm, it provides a dual "visual + auditory" alert, further reducing the possibility of missed fault detection, shortening troubleshooting time, and improving emergency repair efficiency.

[0042] Furthermore, the branch line output terminal is also connected to a ground wire.

[0043] Understandably, when the entire circuit is normal, the Ta and Tc terminals of the phase sequence and phase loss protector 3 are directly connected. At this time, pressing the self-locking switch will illuminate the indicator light, indicating that the power supply output is normally powered. When the AC fuse 1 on the live wire L3 blows, causing a phase loss, the coil of the AC relay 4 de-energizes and trips directly to disconnect the power supply to the circuit, and the power indicator light goes out, indicating that the circuit fault needs to be checked. When the AC fuse 1 on the live wires L1 / L2 blows, causing a phase loss, the phase sequence and phase loss protector 3 recognizes the information and disconnects the Ta and Tc terminals, causing the AC relay 4 to trip and disconnect the power supply to the circuit, and the power indicator light goes out. When a leakage current occurs in the circuit, the first leakage protection switch 2 or the second leakage protection switch 13 reacts quickly and directly disconnects the power supply to the circuit.

[0044] Based on the protection circuit of the above embodiments, the present invention also proposes a low-voltage power supply vehicle, including the protection circuit described above in the embodiments of the present invention.

[0045] In summary, the protection circuit in the above embodiments of this utility model and the low-voltage power supply vehicle using the protection circuit form a multi-layer protection mechanism by sequentially connecting an AC fuse, a leakage current protection switch, a phase loss and phase sequence protector, and an AC relay. When overcurrent, leakage current, or phase loss occurs in the circuit, the power supply can be quickly cut off to avoid equipment damage and safety accidents. Specifically, the AC fuse and leakage current protection switch detect whether the entire circuit is normal. When overcurrent or leakage current occurs, the corresponding equipment quickly trips to protect the safety of the entire circuit. The phase sequence and phase loss protector detect the three-phase power status. When the fuse causes a phase loss, it trips in a short time, causing the AC relay to act and disconnect the power supply to the circuit, avoiding damage to the equipment due to phase loss. At the same time, the voice alarm is linked with the engine signal, and automatically broadcasts a warning when a fault occurs, significantly improving the warning effect in complex environments.

[0046] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0047] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A protection circuit, characterized in that, include: An AC fuse, a first residual current circuit breaker, a phase sequence protection device, an AC relay, and a branch line output terminal are provided. The output terminals of three live wires L1 / L2 / L3 and one neutral wire D1 are connected to the branch line output terminal. Each live wire is connected in series with the AC fuse, the first residual current circuit breaker, and the AC relay from the input terminal. The neutral wire D1 is connected in series with the first residual current circuit breaker. The three live wires L1 / L2 / L3 between the leakage current protection switch and the AC relay are also connected to the A, B and C terminals of the phase loss sequence protector, respectively. The phase loss sequence protector also includes a Ta terminal and a Tc terminal. The Ta terminal of the phase loss sequence protector is connected to the neutral line D1 and connected in series with the contactor of the AC relay. The Tc terminal of the phase loss sequence protector is connected to the live line L3. A voice alarm is also connected to the live wire L3 and the neutral wire D1. The signal terminal of the voice alarm is connected to the engine start signal.

2. The protection circuit according to claim 1, characterized in that, The Tc terminal of the phase loss sequence protector is specifically connected between the leakage current protection switch and the AC relay.

3. The protection circuit according to claim 1, characterized in that, A branch circuit is also connected between the Ta terminal of the phase loss sequence protector and the contactor of the AC relay. The branch circuit is connected to the neutral line D1 and connected in series with the second leakage protection switch.

4. The protection circuit according to claim 3, characterized in that, A self-locking single-pole double-control switch is provided between the Ta terminal of the phase loss sequence protector and the branch circuit.

5. The protection circuit according to claim 4, characterized in that, The self-locking single-opening double-control switch is connected in series between the voice alarm and the engine start signal.

6. The protection circuit according to claim 1, characterized in that, Power indicator lights are also connected to the live wire L3 and the neutral wire D1.

7. The protection circuit according to claim 1, characterized in that, The branch line output is also connected to a ground wire.

8. A low-voltage power supply vehicle, characterized in that, Includes the protection circuit as described in any one of claims 1-7.

Images