Electric vehicle charging circuit

Abstract

The utility model provides an electric vehicle charging circuit, and relates to the technical field of charging, and the electric vehicle charging circuit comprises a storage battery, a mechanical power switch, a distribution box, a plurality of overcurrent protectors, a main relay, a plurality of sub-relays, and a plurality of electric devices. The storage battery is connected with the input end of the distribution box through the mechanical power switch, and the output end of the distribution box is connected with the first input end of the sub-relay. The output end of the sub-relay is connected with each electric device; the storage battery is connected with the main relay through the over-current protector; the main relay is connected with the control end of each sub-relay; the storage battery is connected with the second input end of the sub-relay through the over-current protector. And when the mechanical power switch is switched off and the charging gun is inserted into the charging port, the main relay is switched on and controls each sub-relay to be in a second working state, and the storage battery supplies power to each electric device and charges the electric vehicle.

Description

Technical Field

[0001] The present application relates to the field of charging technology, and in particular to a charging circuit for an electric vehicle. Background Art

[0002] With the development of society, the popularity of pure electric commercial vehicles is increasing. Compared with passenger cars, pure electric commercial vehicles have an additional mechanical power switch, which the driver can manually disconnect to avoid low-voltage battery power supply.

[0003] Currently, when charging a power battery, the main power switch must be turned on before charging can proceed. This means the driver must wait until charging is complete before disconnecting the main power switch. Charging typically takes several hours, requiring a dedicated person to disconnect the main power switch after charging is complete, increasing labor costs for the company. Failure to disconnect the main power switch promptly can lead to battery overcharging, increasing safety risks.

[0004] After searching, the applicant discovered Chinese patent publication number CN221188161U, which discloses a charging power distribution circuit system for new energy vehicles and a new energy vehicle. The system can receive current from an auxiliary controller even when the manual main power switch is not turned on and charging is in progress, eliminating the need to turn on the manual main power switch while the new energy vehicle is charging. However, the system requires an additional auxiliary controller, increasing costs, and lacks overcurrent protection, increasing safety risks. Utility Model Content

[0005] One of the technical problems to be solved by this application is that currently, charging requires a dedicated person to disconnect the main power switch after charging is completed, which increases the company's employment costs. If the main power switch is not disconnected in time, it may cause battery power to be fed back, increasing safety risks.

[0006] To solve the above technical problems, the embodiment of the present application provides an electric vehicle charging circuit, comprising: a battery, a mechanical power switch, a distribution box, multiple overcurrent protectors, a main relay, multiple sub-relays, and multiple electrical devices;

[0007] The battery is connected to the input end of the distribution box through the mechanical power switch, the output end of the distribution box is connected to the first input end of the sub-relay; the output end of the sub-relay is connected to each of the electrical devices;

[0008] The battery is connected to the main relay via the overcurrent protector;

[0009] The main relay is connected to the control end of each sub-relay;

[0010] The battery is connected to the second input terminal of the sub-relay through the overcurrent protector;

[0011] Wherein, the sub-relay has a first working state and a second working state;

[0012] When the sub-relay is in the first working state, the first input terminal and the output terminal of the sub-relay are connected;

[0013] When the sub-relay is in the second working state, the second input terminal and the output terminal of the sub-relay are connected;

[0014] When the mechanical power switch is disconnected and the charging gun is inserted into the charging port, the main relay is turned on and controls each of the sub-relays to be in the second working state. The battery supplies power to each of the electrical devices to charge the electric vehicle.

[0015] In some embodiments, when the electric vehicle is fully charged, the main relay is disconnected, and each of the sub-relays is controlled to be in the first working state, and the battery stops supplying power to each of the electrical devices.

[0016] In some embodiments, the electrical devices correspond one to one with the sub-relays.

[0017] In some embodiments, the number of the electrical devices is N, the number of the sub-relays is N, and the number of the overcurrent protectors is N+1.

[0018] In some embodiments, the overcurrent protector includes: a first overcurrent protection subunit and / or a second overcurrent protection subunit.

[0019] In some embodiments, the first overcurrent protection subunit is specifically a fuse.

[0020] In some embodiments, the second overcurrent protection subunit is specifically a thermistor.

[0021] In some embodiments, the second overcurrent protection subunit includes: a comparator and a switch;

[0022] The first input terminal of the comparator is connected to the battery;

[0023] The second input terminal of the comparator is used to input a reference level;

[0024] The output terminal of the comparator is connected to the switch.

[0025] In some embodiments, the electrical equipment includes: VCU, BMS, motor water pump, instrument, air conditioner and T-BOX.

[0026] In some embodiments, the electric vehicle charging circuit further includes: a battery cooling water pump; the battery cooling water pump is connected to the air conditioner.

[0027] Through the above technical solution, the electric vehicle charging circuit provided by this application does not require an additional auxiliary controller. The electric vehicle can be charged regardless of whether the mechanical power switch is turned on or off. There is no need to worry about the battery power supply caused by the failure to disconnect the mechanical power switch in time after charging is completed, thereby reducing safety risks. The company does not need to specially configure on-duty personnel, reducing labor costs, and at the same time increasing overcurrent protection to further reduce safety risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0029] Figure 1 This is a schematic structural diagram of an electric vehicle charging circuit disclosed in an embodiment of the present application;

[0030] Figure 2 This is a structural diagram of an overcurrent protector disclosed in an embodiment of the present application.

[0031] Description of reference numerals:

[0032] 1. Battery; 2. Mechanical power switch; 3. Distribution box; 4. Overcurrent protector; 41. First overcurrent protection subunit; 42. Second overcurrent protection subunit; 421. Comparator; 422. Switch; 5. Main relay; 6. Sub-relay; 7. Electrical equipment. DETAILED DESCRIPTION

[0033] The following detailed description of the embodiments of the present application is provided in conjunction with the accompanying drawings and examples. The detailed description of the following examples and the accompanying drawings are intended to illustrate the principles of the present application, but are not intended to limit the scope of the present application. The present application may be implemented in many different forms and is not limited to the specific embodiments disclosed herein, but rather includes all technical solutions within the scope of the claims.

[0034] The present application provides these embodiments to make this application thorough and complete, and to fully express the scope of this application to those skilled in the art. It should be noted that: unless otherwise specifically stated, the relative arrangement of parts and steps, the composition of materials, numerical expressions and numerical values set forth in these embodiments should be interpreted as merely exemplary, and not as limiting.

[0035] It should be noted that, in the description of this application, unless otherwise specified, "plurality" means greater than or equal to two; the terms "upper," "lower," "left," "right," "inner," "outer," and the like, indicating directions or positional relationships, are intended solely to facilitate the description of this application and simplify the description, and do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0036] In addition, the terms "first," "second," and similar terms used in this application do not denote any order, quantity, or importance, but are simply used to distinguish different parts. "Perpendicular" does not mean perpendicular in the strict sense, but rather means within the tolerance range. "Parallel" does not mean parallel in the strict sense, but rather means within the tolerance range. "Include" or "comprising" and similar terms mean that the elements preceding the word include the elements listed after the word, and do not exclude the possibility of other elements being included.

[0037] It should also be noted that, in the description of this application, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to direct connections or indirect connections through an intermediary. A person of ordinary skill in the art will understand the specific meanings of the above terms in this application depending on the specific circumstances. When a specific device is described as being located between a first device and a second device, there may or may not be an intervening device between the specific device and the first or second device.

[0038] All terms used in this application have the same meaning as understood by one of ordinary skill in the art to which this application belongs, unless otherwise specifically defined. It should also be understood that terms defined in, for example, common dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology and should not be interpreted in an idealized or highly formal sense, unless explicitly defined as such herein.

[0039] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0040] Reference Manual Figure 1 , shows a structural schematic diagram of an electric vehicle charging circuit disclosed in an embodiment of the present application.

[0041] An embodiment of the present application provides an electric vehicle charging circuit, comprising: a battery 1, a mechanical power switch 2, a distribution box 3, multiple overcurrent protectors 4, a main relay 5, multiple sub-relays 6, and multiple electrical devices 7.

[0042] The battery 1 is connected to the input terminal of the distribution box 3 via the mechanical power switch 2 , and the output terminal of the distribution box 3 is connected to the first input terminal of the sub-relay 6 . The output terminal of the sub-relay 6 is connected to various electrical devices 7 .

[0043] The battery 1 is connected to the main relay 5 via the overcurrent protector 4 .

[0044] The main relay 5 is connected to the control terminals of the sub-relays 6 .

[0045] The battery 1 is connected to the second input terminal of the sub-relay 6 through the overcurrent protector 4 .

[0046] The sub-relay 6 has a first working state and a second working state.

[0047] When the sub-relay 6 is in the first working state, the first input terminal and the output terminal of the sub-relay 6 are connected.

[0048] When the sub-relay 6 is in the second working state, the second input terminal and the output terminal of the sub-relay 6 are connected.

[0049] It should be noted that when the mechanical power switch 2 is disconnected and the charging gun is inserted into the charging port, the main relay 5 is turned on and controls the various sub-relays 6 to be in the second working state. The battery 1 supplies power to the various electrical devices 7 to charge the electric vehicle. This eliminates the need for manual operation and improves the convenience and automation of charging. When the electric vehicle is fully charged, the main relay 5 is disconnected and controls the various sub-relays 6 to be in the first working state. The battery 1 stops supplying power to the various electrical devices 7. There is no need to worry about the battery 1 being powered off due to the failure to disconnect the mechanical power switch 2 in time after charging is completed, which reduces safety risks. The company does not need to assign dedicated on-duty personnel, reducing employment costs.

[0050] When the mechanical power switch 2 is closed, the electric energy of the battery 1 passes through the distribution box 3 and is distributed to various electrical devices 7, thereby charging the electric vehicle.

[0051] Therefore, the electric vehicle charging circuit provided in the present application can charge the electric vehicle regardless of whether the mechanical power switch 2 is turned on or off.

[0052] In a possible implementation, the electrical devices 7 correspond to the sub-relays 6 on a one-to-one basis.

[0053] In the present invention, the number of electrical devices 7 corresponds to the number of sub-relays 6, so that each device has an independent control and protection mechanism. This design ensures the stability and safety of each device during the charging and discharging process.

[0054] In a possible implementation, the number of electrical devices 7 is N, the number of sub-relays 6 is N, and the number of overcurrent protectors 4 is N+1.

[0055] Reference Manual Figure 2 , shows a structural schematic diagram of an overcurrent protector disclosed in an embodiment of the present application.

[0056] In a possible implementation, the overcurrent protector 4 includes: a first overcurrent protection subunit 41 and / or a second overcurrent protection subunit 42 .

[0057] In the present invention, different levels of protection can be achieved by setting different overcurrent protection subunits.

[0058] In a possible implementation manner, the first overcurrent protection subunit 41 is specifically a fuse.

[0059] In the present invention, the fuse has a short response time, is suitable for handling sudden, instantaneous overload conditions of a relatively large current, and can quickly protect the circuit from damage.

[0060] In a possible implementation manner, the second overcurrent protection subunit 42 is specifically a thermistor.

[0061] In this utility model, a thermistor gradually increases its resistance in response to overcurrent or overtemperature, thereby limiting current flow. This component automatically recovers after the fault is resolved, requiring no human intervention. Although thermistors have a slow response time, they provide continuous current limiting, making them suitable for handling minor overcurrent or overtemperature conditions over a longer period, preventing sustained high current from damaging equipment.

[0062] In one possible implementation, the second overcurrent protection subunit 42 includes a comparator 421 and a switch 422 . A first input of the comparator 421 is connected to the battery 1 . A second input of the comparator 421 is used to input a reference level. An output of the comparator 421 is connected to the switch 422 .

[0063] The reference level can be set by those skilled in the art based on practical circumstances, and this is not a limitation of the present invention. By setting different reference levels, it is possible to precisely control when the circuit triggers protection. Using a comparator can improve the adaptability of the overcurrent protection subunit to various situations.

[0064] In the present invention, the comparator's first input is connected to the battery to detect the actual voltage (typically, current is measured via a shunt resistor), while the second input is set to a reference voltage. When the actual voltage exceeds the reference voltage, the comparator immediately outputs a signal, triggering the switch 422 to open, rapidly disconnecting the circuit and protecting other components in the system.

[0065] In a possible implementation, the electrical equipment includes: a VCU (Vehicle Control Unit), a BMS (Battery Management System), a motor water pump, an instrument, an air conditioner, and a T-BOX.

[0066] The VCU (Vehicle Control Unit) serves as the vehicle's central controller, coordinating the operations of various subsystems, including the powertrain, battery management system, and air conditioning system. Including the VCU in the power management system enables centralized management and control of the entire vehicle, ensuring coordinated operation of all systems.

[0067] The BMS is responsible for monitoring the battery's status, including parameters such as voltage, current, and temperature, and managing the battery's charge and discharge processes. Integrating the BMS into the power management system helps optimize the charging process, prevent damage to the battery caused by overcharging and over-discharging, and extend battery life.

[0068] The motor water pump cools the drive motor, while the air conditioning system regulates the interior temperature and cools the battery. During charging, especially during fast charging, the battery and motor can generate significant heat. Incorporating the motor water pump and air conditioning system effectively manages temperature, preventing overheating and improving system safety and stability.

[0069] The instrument panel displays various operating parameters of the vehicle, such as speed, battery level, fault indications, etc. Incorporating the instrument panel into the system can provide real-time status information during charging and use, making it easier for the driver to monitor the vehicle status and make appropriate responses.

[0070] The T-BOX is an in-vehicle information and communication box responsible for data transmission and communication within the vehicle. It enables remote monitoring and management, such as remote charging start, battery status monitoring, and vehicle location tracking, providing greater convenience and safety for users.

[0071] During the charging process of electric vehicles, VCU (Vehicle Control Unit), BMS (Battery Management System), motor water pump, instrument, air conditioner and T-BOX are electrical equipment that must be started. They can achieve all-round management and protection of electric vehicles, ensure the safety of electric vehicles during charging, and improve the performance, safety and user experience of the vehicle.

[0072] In a possible implementation, the electric vehicle charging circuit further includes a battery cooling water pump connected to an air conditioner.

[0073] It should be noted that during the charging process, the battery needs to be cooled, so the battery cooling water pump needs to work. At this time, the BMS wakes up the air conditioner, and the air conditioner outputs a water pump enable signal to the sub-relay 6 corresponding to the battery cooling water pump. Finally, the battery 1 supplies power to the battery water cooling water pump.

[0074] Through the above technical solution, the electric vehicle charging circuit provided by this application does not require an additional auxiliary controller. The electric vehicle can be charged regardless of whether the mechanical power switch is turned on or off. There is no need to worry about the battery power supply caused by the failure to disconnect the mechanical power switch in time after charging is completed, thereby reducing safety risks. The company does not need to specially configure on-duty personnel, reducing labor costs, and at the same time increasing overcurrent protection to further reduce safety risks.

[0075] So far, the various embodiments of the present application have been described in detail. To avoid obscuring the concept of the present application, some details well known in the art have not been described. Based on the above description, those skilled in the art can fully understand how to implement the technical solutions disclosed herein.

[0076] Although some specific embodiments of the present application have been described in detail through examples, those skilled in the art will understand that the above examples are for illustrative purposes only and are not intended to limit the scope of the present application. Those skilled in the art will understand that the above embodiments may be modified or some technical features may be replaced by equivalents without departing from the scope and spirit of the present application. In particular, as long as there are no structural conflicts, the various technical features mentioned in the various embodiments may be combined in any manner.

Claims

1. An electric vehicle charging circuit, characterized in that: include: A battery (1), a mechanical power switch (2), a distribution box (3), a plurality of overcurrent protectors (4), a main relay (5), a plurality of sub-relays (6), and a plurality of electrical devices (7); The battery (1) is connected to the input end of the distribution box (3) via the mechanical power switch (2); the output end of the distribution box (3) is connected to the first input end of the sub-relay (6); the output end of the sub-relay (6) is connected to each of the electrical devices (7); The battery (1) is connected to the main relay (5) via the overcurrent protector (4); The main relay (5) is connected to the control end of each sub-relay (6); The battery (1) is connected to the second input terminal of the sub-relay (6) via the overcurrent protector (4); Wherein, the sub-relay (6) has a first working state and a second working state; When the sub-relay (6) is in the first working state, the first input terminal and the output terminal of the sub-relay (6) are connected; When the sub-relay (6) is in the second working state, the second input terminal and the output terminal of the sub-relay (6) are connected; When the mechanical power switch (2) is disconnected and the charging gun is inserted into the charging port, the main relay (5) is turned on and controls each of the sub-relays (6) to be in the second working state, and the storage battery (1) supplies power to each of the electrical devices (7) to charge the electric vehicle.

2. The electric vehicle charging circuit according to claim 1, characterized in that: When the electric vehicle is fully charged, the main relay (5) is disconnected, and each of the sub-relays (6) is controlled to be in the first working state, and the storage battery (1) stops supplying power to each of the electrical devices (7).

3. The electric vehicle charging circuit according to claim 1, characterized in that: The electrical equipment (7) corresponds to the sub-relays (6) on a one-to-one basis.

4. The electric vehicle charging circuit according to claim 3, characterized in that: The number of the electrical devices (7) is N, the number of the sub-relays (6) is N, and the number of the overcurrent protectors (4) is N+1, where N represents a positive integer.

5. The electric vehicle charging circuit according to claim 1, characterized in that: The overcurrent protector (4) comprises: a first overcurrent protection subunit (41) and / or a second overcurrent protection subunit (42).

6. The electric vehicle charging circuit according to claim 5, characterized in that: The first overcurrent protection subunit (41) is specifically a fuse.

7. The electric vehicle charging circuit according to claim 5, characterized in that: The second overcurrent protection subunit (42) is specifically a thermistor.

8. The electric vehicle charging circuit according to claim 5, characterized in that: The second overcurrent protection subunit (42) includes: a comparator (421) and a switch (422); The first input terminal of the comparator (421) is connected to the battery (1); The second input terminal of the comparator (421) is used to input a reference level; The output end of the comparator (421) is connected to the switch (422).

9. The electric vehicle charging circuit according to claim 1, characterized in that: The electrical equipment includes: VCU, BMS, motor water pump, instrument, air conditioner and T-BOX.

10. The electric vehicle charging circuit according to claim 9, characterized in that: Also includes: Battery cooling water pump; the battery cooling water pump is connected to the air conditioner.

Images