Bidirectional charging system of battery pack of vehicle and vehicle

Abstract

The invention provides a two-way charging system for a battery pack of a vehicle and the vehicle, and the two-way charging system comprises an input end which is coupled with charging equipment; the output end is coupled with an external load of the vehicle; the charger is coupled between the battery pack and the input end and between the battery pack and the output end so as to charge and discharge the battery pack, the bidirectional charging system comprises a first relay and a second relay, the input end, the first relay, the second relay and the charger are sequentially connected in series, and the output end is connected to the first relay and the second relay in parallel. According to the bidirectional charging system for the battery pack of the vehicle, charging of the battery pack and discharging of the battery pack to the external load can be achieved by switching the relay, the electric power use of the battery pack can be optimized, and the energy utilization rate is increased.

Description

Technical Field

[0001] This invention relates to the field of vehicles, and more particularly to the field of vehicle battery systems. More specifically, it relates to a bidirectional charging system for a vehicle battery pack and a vehicle using the bidirectional charging system. Background Technology

[0002] With the rapid development of new energy vehicle technology, electric vehicles are increasingly being used in daily life. Typically, the battery packs of electric vehicles are primarily used to store electrical energy and replenish it through charging to power the vehicle. However, in practical applications, especially in vehicles that frequently operate outdoors, such as light commercial vehicles and heavy trucks, if external load electrical appliances such as lighting equipment are required, a generator or other power source needs to be carried. This increases the vehicle's weight and cost, and also limits operational efficiency and flexibility.

[0003] Therefore, a system is needed to charge and discharge battery packs to improve their energy efficiency. Summary of the Invention

[0004] The purpose of this invention is to solve the problems existing in the prior art and provide a bidirectional charging system for a vehicle battery pack, which improves the energy utilization rate of the battery pack in a cost-effective and reliable manner.

[0005] Therefore, according to one aspect of the present invention, a bidirectional charging system for a vehicle battery pack is provided, the bidirectional charging system comprising: an input terminal coupled to a charging device; an output terminal coupled to an external load of the vehicle; and a charger coupled between the battery pack and the input terminal and the output terminal to charge and discharge the battery pack, wherein the bidirectional charging system includes a first relay and a second relay, the input terminal, the first relay, the second relay and the charger are connected in series, and the output terminal is connected in parallel to the first relay and the second relay.

[0006] Based on the above-described technical concept, the present invention may further include any one or more of the following optional forms.

[0007] In some alternative forms, the bidirectional charging system includes a control unit configured to control the closing and opening of the first and second relays such that the battery pack is charged when the first and second relays are closed, and the battery pack is discharged when the first relay is open and the second relay is closed.

[0008] In some alternative forms, the bidirectional charging system includes a residual current protection device coupled between the second relay and the output terminal to detect residual current in the bidirectional charging system.

[0009] In some alternative configurations, the control unit is configured to disconnect the residual current protection device before charging the battery pack, thereby preventing the battery pack from discharging.

[0010] In some alternative configurations, the control unit is configured to close the residual current protection device before discharging the battery pack to detect residual current in the bidirectional charging system.

[0011] In some alternative configurations, the control unit is configured to control the residual current protection device to disconnect and provide an alarm signal when the residual current in the bidirectional charging system exceeds a preset threshold.

[0012] In some alternative forms, the bidirectional charging system includes a voltage sensor and / or a current sensor and / or a temperature sensor, wherein the voltage sensor is configured to detect the voltage of the first relay and / or the second relay, and / or the current sensor is configured to detect the current of the first relay and / or the second relay, and / or the temperature sensor is configured to detect the temperature of the first relay and / or the second relay.

[0013] In some alternative forms, the control unit is configured to provide an alarm signal in response to the detected voltage being greater than a first threshold and / or the detected current being greater than a second threshold and / or the detected temperature being greater than a third threshold and / or the voltage difference across the first relay and / or the second relay being less than a fourth threshold.

[0014] In some alternative forms, the bidirectional charging system is integrated within a housing, the housing including a cover and a box-shaped component attached to the cover, wherein a microswitch is provided between the cover and the box-shaped component, the microswitch being configured to enable the bidirectional charging system when closed and deactivate the bidirectional charging system when open.

[0015] According to another aspect of the present invention, a vehicle is provided, the vehicle including the bidirectional charging system of the battery pack of the vehicle described above.

[0016] In some alternative configurations, the bidirectional charging system includes a control unit, and the vehicle includes a body controller, wherein the control unit communicates with the body controller to send an alarm signal to the body controller, and the body controller, in response to the alarm signal, sends an alarm notification to the user via the vehicle's dashboard and / or infotainment system.

[0017] In some alternative configurations, the vehicle includes a battery pack, a charging port, and a discharging port, with the input of the bidirectional charging system coupled to the charging port and the output of the bidirectional charging system coupled to the discharging port, so that the battery pack is charged via the charging port and discharged via the discharging port.

[0018] This invention provides a bidirectional charging system for a vehicle's battery pack. By switching relays, the charging of the battery pack and the discharge of the battery pack to an external load can be achieved, realizing bidirectional energy flow. The switching between charging and discharging states of the battery pack can be achieved by opening and closing the relays. This simplifies system design, optimizes the power use of the battery pack, and improves energy efficiency. Attached Figure Description

[0019] Other features and advantages of the present invention will be better understood through the following detailed description of optional embodiments in conjunction with the accompanying drawings, wherein:

[0020] Figure 1 A schematic diagram of a bidirectional charging system for a vehicle battery pack according to an embodiment of the present invention is shown.

[0021] Figure 2 A schematic circuit diagram of a bidirectional charging system for a vehicle battery pack according to an embodiment of the present invention is shown; and

[0022] Figure 3 A schematic diagram of the housing of a bidirectional charging system for a vehicle battery pack according to an embodiment of the present invention is shown. Detailed Implementation

[0023] The implementation and use of the embodiments are discussed in detail below. While the exemplary systems described below include software and / or firmware executed on hardware among other components, it should be noted that these examples are merely illustrative and should not be considered limiting. Therefore, although exemplary methods and systems have been described below, those skilled in the art will readily understand that the specific embodiments discussed are merely exemplary of particular ways of implementing and using the invention, and not intended to limit the scope of the invention.

[0024] Furthermore, the block diagrams in the accompanying drawings illustrate possible architectures for implementations of systems according to various embodiments of the present invention. It should be noted that each block in the block diagrams can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0025] Currently, the primary function of vehicle battery pack systems is charging, and they can only meet the vehicle's basic driving needs with the power from the battery pack. The inventors discovered that when vehicles operate outdoors for extended periods, they not only need to meet their own power requirements but also frequently need to provide power to external electrical loads. Therefore, it is necessary for the battery pack to not only charge to provide power to the vehicle but also discharge to external loads to improve the energy utilization rate of the battery pack.

[0026] Combination Figure 1 and Figure 2 As shown, a bidirectional charging system for a vehicle battery pack according to an embodiment of the present invention includes an input terminal 110, an output terminal 120, and a charger 130. The input terminal 110 is coupled to a charging device (not shown) to allow power to enter the bidirectional charging system from the charging device, which may be, for example, a charging station. The output terminal 120 is coupled to an external load to allow power to enter the external load (not shown) from the bidirectional charging system to charge the external load, which may be a lighting device, construction equipment, etc., and the vehicle may include a charging port and a discharging port, such as a charging socket and a discharging socket. The charging port is coupled to the input terminal 110 of the bidirectional charging system, and the discharging port is coupled to the output terminal 120 of the bidirectional charging system, so that the battery pack can be charged via the charging port and discharged via the discharging port. Specifically, in the case of a heavy truck, the charging port can be located near the rear fender of the vehicle, and the discharging port can be located at the rear panel of the vehicle. The discharging port is connected to the external load of the vehicle, so that the power of the battery pack can be released to the external load of the vehicle through the output terminal 120 of the bidirectional charging system and the discharging port to charge the external load of the vehicle.

[0027] The bidirectional charging system also includes a charger 130, which may be, for example, an on-board charger (OBC). The charger 130 is typically used to convert alternating current (AC) to high-voltage direct current (DC) to charge the battery pack, and it is installed between the battery pack 300 and the vehicle's charging port. In this embodiment, the charger 130 is coupled between the battery pack 300 and the input terminal 110 and output terminal 120 of the bidirectional charging system, allowing the battery pack 300 to be charged and discharged via the bidirectional charging system. Thus, the bidirectional charging system can be installed between the vehicle's battery pack 300 and the charging port, i.e., inside the vehicle, eliminating the need for an additional socket adapter for discharging the battery pack 300 into the vehicle's charging port, thereby improving the charging and discharging efficiency of the battery pack 300.

[0028] exist Figure 2 In this bidirectional charging system, a first relay 140 and a second relay 150 are included. The input terminal 110, the first relay 140, the second relay 150, and the charger 130 are connected in series. The output terminal 120 is connected in parallel to the first relay 140 and the second relay 150. Thus, when it is necessary to switch the charging and discharging states of the battery pack 300, only the on / off state of the first relay 140 and the second relay 150 needs to be switched. Figure 2 As shown, in this embodiment, both the first relay 140 and the second relay 150 include four relays. These four relays can be connected to the three phase lines and the neutral line respectively to achieve a three-phase power connection. It is understood that the number of relays is not limited to that shown in the figure and can be changed as needed.

[0029] When both the first relay 140 and the second relay 150 are closed, the input terminal 110 is connected to the charger 130. When the vehicle is connected to the charging equipment, the AC current of the charging equipment flows through the input terminal 110, the first relay 140, the second relay 150, and the charger 130. The charger 130 converts the AC current into DC current and outputs it to the battery pack 300 to charge the battery pack 300. When the first relay 140 is open and the second relay 150 is closed, the input terminal 110 is disconnected, and the output terminal 120 is connected to the charger 130. When the vehicle is connected to an external load, the power from the battery pack 300 is output to the external load via the charger 130, the second relay 150, and the output terminal 120 to charge the external load. When the first relay 140 is closed and the second relay 150 is open, the input terminal 110 and the output terminal 120 are disconnected from the charger 130, and the battery pack 300 does not charge or discharge. When an external load requires AC power, an inverter can be installed, for example, between the output terminal 120 of the bidirectional charging system and the second relay 150, to convert the DC power of the battery pack 300 into AC power for output to the external load.

[0030] exist Figure 2 The bidirectional charging system also includes a control unit 160, which can control the closing and opening of the first relay 140 and the second relay 150 to charge and discharge the battery pack 300. In this embodiment, the control unit 160 can be a microcontroller unit (MCU). Through the MCU, the closing and opening of the relays can be automatically controlled according to the state of the battery pack 300 (e.g., voltage, current, state of charge, etc.), and the state of the battery pack 300 can be intelligently switched according to the actual situation. For example, the discharge can be stopped when the state of charge of the battery pack 300 is too low, without manual intervention, thus ensuring the working performance of the battery pack 300.

[0031] In some embodiments, the bidirectional charging system includes a residual current device (RCD) 170, coupled between the second relay 150 and the output terminal 120, for detecting residual current in the bidirectional charging system. When the residual current device 170 is closed, it can detect whether there is residual current in the bidirectional charging system, promptly identify faults such as leakage current or short circuits, reduce the risk of electrical fires and electric shocks, thereby protecting the safety of the bidirectional charging system and the user, and improving the safety and reliability of the bidirectional charging system.

[0032] The control unit 160 can control the residual current protection device 170 to disconnect before charging the battery pack 300, thereby preventing the battery pack 300 from discharging, avoiding power loss, and improving the energy utilization rate of the battery pack 300. Additionally, the control unit 160 can control the residual current protection device 170 to close before discharging the battery pack 300, ensuring that there is no leakage current in the bidirectional charging system before the battery pack 300 discharges, thus preventing potential equipment damage, fire, electric shock, and other accidents. Specifically, the residual current protection device 170 is typically a relay with a residual current sensing coil. When the residual current protection device 170 is closed, current is allowed to flow normally. Simultaneously, the sensing coil monitors the current flowing into and out of the relay. If there is no leakage current, the inflow and outflow currents should be approximately equal. When leakage current occurs, the inflow and outflow currents are no longer equal, and the sensing coil detects the current difference (i.e., residual current). If the residual current exceeds a preset threshold, the control unit 160 controls the relay to disconnect, preventing the battery pack 300 from discharging, and the control unit 160 provides an alarm signal. In some implementations, the preset threshold may be, for example, 10mA. It is understood that the preset threshold for residual current can be set and changed as needed, and is not limited thereto.

[0033] In some embodiments, the bidirectional charging system may include a voltage sensor (not shown) and / or a current sensor (not shown) and / or a temperature sensor (not shown). The voltage sensor is used to detect the voltage of the first relay 140 and / or the second relay 150, the current sensor is used to detect the current flowing through the first relay 140 and / or the second relay 150, and the temperature sensor is used to detect the temperature of the first relay 140 and / or the second relay 150. This allows for real-time monitoring of the status of the first relay 140 and / or the second relay 150, timely detection of faults and abnormalities, reduction of the risk of damage to the bidirectional charging system, and improvement of the safety and reliability of the bidirectional charging system.

[0034] Specifically, such as Figure 2 As indicated by arrows A and B, the detection data from the voltage sensor and / or current sensor and / or temperature sensor will be transmitted to the control unit 160. When the detected voltage exceeds a first threshold and / or the detected current exceeds a second threshold and / or the detected temperature exceeds a third threshold, i.e., when the first relay 140 and / or the second relay 150 experience overvoltage and / or overcurrent and / or overtemperature, the control unit 160 can provide an alarm signal. The vehicle can respond to this alarm signal by performing protective actions, such as disconnecting the first relay 140 and / or the second relay 150. It is understood that the fault conditions of the first relay 140 and / or the second relay 150 are not limited to these. For example, if the voltage difference across the first relay 140 and / or the second relay 150 is less than a fourth threshold, the first relay 140 and / or the second relay 150 may stick together, and the control unit 160 can provide an alarm signal to perform protective actions. It should be noted that the first, second, third, and fourth thresholds can be set as needed and are not limited here.

[0035] like Figure 3As shown, in this invention, the bidirectional charging system can be integrated into a housing, which includes a cover 210 and a box-shaped component 220 attached to the cover 210. A microswitch 230 is provided between the cover 210 and the box-shaped component 220. When the cover 210 and the box-shaped component 220 are in closed contact, the cover 210 applies pressure to the microswitch 230, causing the microswitch 230 to close and activating the bidirectional charging system. In some embodiments, the microswitch 230 can be coupled to a high-voltage connector, which can be, for example, located at the output end of the battery pack 300. When the microswitch 230 is closed, the bidirectional charging system can normally discharge to an external load. Alternatively, the high-voltage connector can be, for example, located at the vehicle's charging port, allowing power to flow normally into the bidirectional charging system when the microswitch 230 is closed. A certain gap exists between the cover 210 and the box-shaped component 220, causing the microswitch 230 to open, disabling the bidirectional charging system and preventing the battery pack 300 from charging and discharging. In this way, the charging and discharging process of the battery pack 300 can be automatically stopped when the casing of the bidirectional charging system is opened, which is equivalent to cutting off the high-voltage power supply. This prevents personnel from coming into contact with high-voltage electricity during the maintenance or inspection of the bidirectional charging system, ensuring the safety of personnel and further improving the safety and reliability of the bidirectional charging system. In addition, placing the bidirectional charging system in a separate casing facilitates future upgrades. For example, by modifying the program of the control unit 160 and the hardware of the bidirectional charging system, the bidirectional charging system can support more functions, such as wireless charging and solar power.

[0036] In some embodiments, the control unit 160 can communicate with the vehicle's body control unit (VCU) 180. As described above, when a fault is detected in the first relay 140 and / or the second relay 150, and / or residual current exists in the bidirectional charging system, the control unit 160 provides an alarm signal. In response to this alarm signal, the body control unit 180 can send an alarm notification to the user via the vehicle's instrument panel and / or infotainment system, allowing the user to perform, for example, relay repair or replacement. Thus, the control unit 160 can provide real-time feedback on relay status, bidirectional charging system status, etc., to the body control unit 180, enabling the body control unit 180 to quickly make adjustment decisions based on the status of various vehicle subsystems to dynamically adjust the vehicle's operating state. For example, when the battery pack 300 has sufficient power, the body control unit 180 can allow the battery pack 300 to provide more power; when the battery pack 300 has limited power or the bidirectional charging system malfunctions, the body control unit 180 can adjust the vehicle to enter energy-saving mode or limit maximum power output to protect the battery pack 300 and extend the driving range.

[0037] It should be understood that the embodiments shown in the figures are only optional configurations of the bidirectional charging system of the battery pack of the vehicle according to the present invention. However, they are merely exemplary embodiments and not limitations on the present invention. Other configurations may be adopted without departing from the spirit and scope of the present invention.

[0038] The technical content and features of the present invention have been disclosed above. However, it is understood that those skilled in the art can make various changes and improvements to the disclosed concepts under the inventive concept of the present invention, all of which fall within the protection scope of the present invention. The description of the above embodiments is illustrative rather than restrictive, and the protection scope of the present invention is determined by the claims.

Claims

1. A bidirectional charging system for a vehicle battery pack, characterized in that, The bidirectional charging system includes: An input terminal (110) is coupled to a charging device; Output terminal (120), the output terminal (120) is coupled to the external load of the vehicle; A charger (130) is coupled between the battery pack (300) and the input terminal (110) and the output terminal (120) to charge and discharge the battery pack (300). The bidirectional charging system includes a first relay (140) and a second relay (150). The input terminal (110), the first relay (140), the second relay (150) and the charger (130) are connected in series. The output terminal (120) is connected in parallel to the first relay (140) and the second relay (150).

2. The bidirectional charging system according to claim 1, characterized in that, The bidirectional charging system includes a control unit (160) configured to control the closing and opening of a first relay (140) and a second relay (150) such that the battery pack (300) is charged when the first relay (140) and the second relay (150) are closed, and the battery pack (300) is discharged when the first relay (140) is open and the second relay (150) is closed.

3. The bidirectional charging system according to claim 2, characterized in that, The bidirectional charging system includes a residual current protection device (170) coupled between the second relay (150) and the output terminal (120) to detect the residual current in the bidirectional charging system.

4. The bidirectional charging system according to claim 3, characterized in that, The control unit (160) is configured to control the residual current protection device (170) to disconnect before charging the battery pack (300) to prevent the battery pack (300) from discharging.

5. The bidirectional charging system according to claim 3, characterized in that, The control unit (160) is configured to close the residual current protection device (170) before discharging the battery pack (300) to detect the residual current in the bidirectional charging system.

6. The bidirectional charging system according to claim 5, characterized in that, The control unit (160) is configured to control the residual current protection device (170) to disconnect and provide an alarm signal when the residual current in the bidirectional charging system exceeds a preset threshold.

7. The bidirectional charging system according to claim 2, characterized in that, The bidirectional charging system includes a voltage sensor and / or a current sensor and / or a temperature sensor, wherein the voltage sensor is configured to detect the voltage of the first relay (140) and / or the second relay (150), and / or the current sensor is configured to detect the current of the first relay (140) and / or the second relay (150), and / or the temperature sensor is configured to detect the temperature of the first relay (140) and / or the second relay (150).

8. The bidirectional charging system according to claim 7, characterized in that, The control unit (160) is configured to provide an alarm signal in response to the detection of a voltage greater than a first threshold and / or the detection of a current greater than a second threshold and / or the detection of a temperature greater than a third threshold and / or the voltage difference across the first relay (140) and / or the second relay (150) being less than a fourth threshold.

9. The bidirectional charging system according to any one of claims 1 to 8, characterized in that, The bidirectional charging system is integrated within a housing, which includes a cover (210) and a box-shaped component (220) attached to the cover (210). A micro switch (230) is provided between the cover (210) and the box-shaped component (220). The micro switch (230) is configured to enable the bidirectional charging system when closed and disable the bidirectional charging system when open.

10. A vehicle, characterized in that, The vehicle includes a bidirectional charging system for the battery pack of the vehicle according to any one of claims 1 to 9.

11. The vehicle according to claim 10, characterized in that, The bidirectional charging system includes a control unit (160), and the vehicle includes a body controller (180), wherein the control unit (160) communicates with the body controller (180) to send an alarm signal to the body controller (180), and the body controller (180) responds to the alarm signal by sending an alarm notification to the user through the vehicle's dashboard and / or infotainment system.

12. The vehicle according to claim 10 or 11, characterized in that, The vehicle includes a battery pack (300), a charging port, and a discharging port. The input terminal (110) of the bidirectional charging system is coupled to the charging port, and the output terminal (120) of the bidirectional charging system is coupled to the discharging port, so that the battery pack (300) is charged via the charging port and discharged via the discharging port.

Images