Battery charging and discharging control circuit, device and automobile

Abstract

The application provides a battery charging and discharging control circuit, device and automobile. The control circuit comprises a battery, a direct current converter, a switch structure and a vehicle controller. The switch structure comprises a control end. The battery is connected with the switch structure, and the switch structure is connected with the direct current converter. The input end of the vehicle controller is connected with the battery, and the output end of the vehicle controller is connected with the control end. The vehicle controller is used for determining an output voltage based on the electric quantity of the battery and transmitting the output voltage to the control end. The control end is used for closing or opening the switch structure according to the output voltage, so that the direct current converter charges or does not charge the battery. The control circuit realizes the charging or discharging control of the battery, avoids the problems caused by insufficient or overcharging of the battery, and solves the problem of how to control the charging and discharging of the battery. In addition, the closing or opening of the switch structure is controlled by the vehicle controller, so that the control accuracy is higher and the effect is better.

Description

Technical Field

[0001] This application relates to the field of automotive technology, and in particular to a battery charging and discharging control circuit, device, and automobile. Background Technology

[0002] In the low-voltage circuit of a vehicle's hybrid power system, when the battery charge is high, not only does the charging efficiency decrease and energy consumption increase, but overcharging also affects the battery's lifespan; conversely, if the battery charge is insufficient, it cannot provide enough power to the load. Therefore, charge and discharge control of the battery is necessary.

[0003] In existing technology, a relay is connected in series between the battery and the DC-DC converter in the low-voltage circuit. The charging of the battery by the DC-DC converter is controlled by controlling the opening and closing of the relay. However, the relay has a slow switching speed, poor control effect, and large size, making it impractical.

[0004] Therefore, improving the control of battery charging and discharging is a technical problem that urgently needs to be solved. Summary of the Invention

[0005] This application provides a battery charging and discharging control circuit, device, and automobile to solve the problem of poor charging and discharging control effect of batteries.

[0006] On one hand, this application provides a battery charging and discharging control circuit, the control circuit including: a battery, a DC-DC converter, a switching structure, and a vehicle controller; the switching structure includes a control terminal;

[0007] The battery is connected to the switch structure, and the switch structure is connected to the DC-DC converter; the input terminal of the vehicle controller is connected to the battery, and the output terminal of the vehicle controller is connected to the control terminal.

[0008] The vehicle controller is used to determine the output voltage based on the battery charge and output the output voltage to the control terminal.

[0009] The control terminal is used to close or open the switching structure according to the output voltage, so that the DC converter charges or does not charge the battery.

[0010] Optionally, the switching structure includes a diode and a switching element, the switching element including a first connection terminal, a second connection terminal, and a control terminal;

[0011] The first connection terminal is connected to the positive terminal of the diode and the battery, and the second connection terminal is connected to the negative terminal of the diode and the DC-DC converter.

[0012] The diode is used to enable unidirectional conduction from the battery to the DC-DC converter, so as to supply power to the load when the DC-DC converter is not working;

[0013] The control terminal is used to close or open the switching element according to the output voltage, so that the DC converter charges or does not charge the battery.

[0014] Optionally, the switching element includes a MOSFET, the source of the MOSFET is the first connection terminal, the drain of the MOSFET is the second connection terminal, and the gate of the MOSFET is the control terminal.

[0015] Optionally, the vehicle controller includes a microcontroller unit, an amplifier circuit, and a comparator structure;

[0016] The microcontroller unit is connected to the input terminal of the amplifier circuit, the input terminal of the amplifier circuit is connected to the battery, the output terminal of the amplifier circuit is connected to the positive input terminal of the comparator structure, the negative input terminal of the comparator structure is connected to the battery, and the output terminal of the comparator structure is connected to the control terminal.

[0017] The microcontroller unit is used to determine the control signal based on the battery charge and to provide the control signal to the amplifier circuit.

[0018] The amplifier circuit is used to determine the output voltage of the amplifier circuit according to the control signal, and to provide the output voltage to the positive input terminal of the comparator structure.

[0019] The battery is used to provide a negative input voltage to the negative input terminal of the comparator structure;

[0020] The comparison structure is used to determine and output the output voltage based on the output terminal voltage and the negative input voltage.

[0021] Optionally, the comparison structure includes a comparator, a positive voltage divider resistor, and a negative voltage divider resistor;

[0022] One end of the positive voltage divider resistor is connected to the output terminal of the amplifier circuit, and the other end of the positive voltage divider resistor is connected to the positive input terminal of the comparator. One end of the negative voltage divider resistor is connected to the battery, and the other end of the negative voltage divider resistor is connected to the negative input terminal of the comparator. The output terminal of the comparator is connected to the control terminal.

[0023] The positive voltage divider resistor is used to divide the output voltage and provide the divided output voltage to the positive input terminal of the comparator.

[0024] The negative voltage divider resistor is used to divide the negative input voltage and provide the divided negative input voltage to the negative input terminal of the comparator.

[0025] The comparator is used to compare the output voltage after voltage division with the negative input voltage after voltage division, and to determine and output the output voltage.

[0026] Optionally, the positive voltage divider resistor is greater than the negative voltage divider resistor.

[0027] Optionally, the amplifier circuit includes a transistor, the base of which is the input terminal of the amplifier circuit, the collector of which is the output terminal of the amplifier circuit, and the emitter of which is grounded.

[0028] Optionally, the control circuit further includes a battery monitoring sensor connected to the battery. The battery monitoring sensor is used to monitor the battery's charge level and provide the battery's charge level information to the vehicle controller.

[0029] On the other hand, this application also provides a battery charging and discharging control device, including the control circuit as described in any of the above claims.

[0030] On the other hand, this application also provides a vehicle that includes the control circuitry described in any of the preceding claims.

[0031] This application provides a battery charging and discharging control circuit, device, and automobile. The battery charging and discharging control circuit includes a battery, a DC-DC converter, a switching structure, and a vehicle controller. The switching structure includes a control terminal. The battery is connected to the switching structure, and the switching structure is connected to the DC-DC converter. The input terminal of the vehicle controller is connected to the battery, and the output terminal of the vehicle controller is connected to the control terminal. The vehicle controller determines an output voltage based on the battery's charge level and outputs the output voltage to the control terminal. The control terminal closes or opens the switching structure according to the output voltage, causing the DC-DC converter to charge or not charge the battery. By controlling the opening and closing of the switching structure through the vehicle controller, the charging or discharging of the battery is achieved, avoiding problems caused by insufficient battery charge or overcharging, and solving the problem of how to control battery charging and discharging. Furthermore, controlling the opening and closing of the switching structure through the vehicle controller provides higher control precision and better performance. Attached Figure Description

[0032] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0033] Figure 1 A schematic diagram of the low-voltage circuit of a hybrid electric vehicle system;

[0034] Figure 2 A schematic diagram of a battery charging and discharging control circuit provided in an embodiment of this application;

[0035] Figure 3 A schematic diagram of another battery charging and discharging control circuit provided in an embodiment of this application;

[0036] Figure 4 This is a schematic diagram of a battery charging and discharging control logic provided in an embodiment of this application.

[0037] Figure label:

[0038] 10-Battery; 20-DC converter; 30-Power supply load; 301-12V starter; 40-Switch structure; 401-Control terminal; 41-Diode; 42-Switch element; 421-First connection terminal; 422-Second connection terminal; 50-Vehicle controller; 51-Microcontroller unit; 52-Amplifier circuit; 53-Comparator structure; 531-Comparator; 532-Positive voltage divider resistor; 533-Negative voltage divider resistor.

[0039] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0040] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0041] The terms “positive,” “negative,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0042] Hybrid systems that couple a single motor to the even-numbered shaft of a dual-clutch transmission can achieve good fuel economy and have the advantages of low cost and short development cycle, and are widely used in the automotive industry.

[0043] For example, Figure 1 This is a schematic diagram of the low-voltage circuit of a hybrid powertrain system for automobiles. Figure 1 As shown, in the low-voltage circuit, the battery 10 is connected to the DC-DC converter 20, and both supply power to the low-voltage load 30. The 12V starter 301 is connected to the battery 10 and is powered by the battery 10. The power supply load connected to the battery 10 can be other electrical equipment besides the starter; this application does not impose any restrictions, and the figure is merely an example.

[0044] In practical applications, if the battery's charge is insufficient, it will not be able to provide enough power to the load. Therefore, when the battery's charge is low, the DC-DC converter needs to be controlled to charge the battery. However, when the battery's charge is high, not only will the charging efficiency decrease and energy consumption increase, but overcharging will also affect the battery's lifespan. Therefore, charge and discharge control of the battery is necessary.

[0045] In one example, a relay is connected in series between the battery and the DC-DC converter. By controlling the opening and closing of the relay, the DC-DC converter can be controlled to charge the battery. However, relays have slow switching speeds, poor control performance, and are bulky, making them impractical.

[0046] To address the aforementioned technical problems, this application provides a battery charging and discharging control circuit, device, and automobile. By setting up a switching structure and a vehicle controller, the vehicle controller controls the closing or opening of the switching structure according to the battery's charge level, thereby controlling the DC-DC converter to charge or not charge the battery. This achieves battery charging and discharging control, avoiding problems caused by insufficient battery charge or overcharging, and solving the problem of how to control battery charging and discharging. In addition, it also improves control accuracy and control effect.

[0047] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0048] Figure 2 This is a schematic diagram of a battery charging and discharging control circuit provided in an embodiment of this application. Figure 2 As shown, the battery charging and discharging control circuit provided in this application embodiment includes: a battery 10, a DC-DC converter 20, a switching structure 40, and a vehicle controller 50; wherein, the switching structure 40 includes a control terminal 401.

[0049] The battery 10 is connected to the switch structure 40, and the switch structure 40 is connected to the DC-DC converter 20; the input terminal of the vehicle controller 50 is connected to the battery 10, and the output terminal of the vehicle controller 50 is connected to the control terminal 401.

[0050] The vehicle controller 50 determines the output voltage based on the charge level of the battery 10 and outputs the output voltage to the control terminal 401.

[0051] The control terminal 401 is used to close or open the switch structure 40 according to the output voltage so that the DC converter 20 charges or does not charge the battery 10.

[0052] For example, after the high voltage is applied, the vehicle controller 50 monitors the battery level of the battery 10 in real time. Then, based on the battery level, it determines whether the battery 10 needs charging and outputs different voltages based on whether charging is required, so that the control terminal 401 can close or open the switch structure according to the output voltage. Specifically, when charging is required, the vehicle controller 50 outputs a voltage that can control the switch structure to close; when charging is not required, it outputs a voltage that can control the switch structure to open.

[0053] The switching structure can close or open according to the magnitude of the control terminal voltage, thereby enabling or disabling the connection between the DC-DC converter 20 and the battery 10. For example, when charging is required, the vehicle controller 50 outputs a high voltage. Upon receiving the high voltage, the control terminal 401 closes the switching structure 40, allowing the DC-DC converter 20 to charge the battery 10. When charging is not required, the vehicle controller 50 outputs a low voltage. Upon receiving the low voltage, the control terminal 401 opens the switching structure 40, preventing the DC-DC converter 20 from charging the battery 10. The setting of high and low voltage is determined based on the characteristics of the switching structure 40. This application does not impose any restrictions on whether the switching structure 40 closes when the control terminal 401 receives a high voltage and opens when it receives a low voltage.

[0054] For example, the vehicle controller 50 can monitor the battery 10's charge level in real time through various means such as a battery monitoring sensor or a battery monitoring system, and this application does not impose any limitations. In one example, the control circuit also includes a battery monitoring sensor (not shown in the figure), which is connected to the battery 10. The battery monitoring sensor is used to monitor the battery's charge level and provide the battery's charge level information to the vehicle controller 50.

[0055] For example, the battery monitoring sensor monitors the power information of the battery 10 in real time and sends the real-time power information to the vehicle controller 50 so that the vehicle controller 50 can control the charging and discharging of the battery 10 in a timely manner according to the power of the battery 10.

[0056] For example, if the charge level of battery 10 is lower than a preset low charge threshold, it indicates that battery 10 needs to be charged; if the charge level of battery 10 is higher than a preset high charge threshold, it indicates that battery 10 does not need to be charged. The low charge threshold can be set according to the power consumption of the vehicle's power supply load to ensure that the vehicle can supply power normally until the battery charge level falls below the low charge threshold. The high charge threshold can be set according to the characteristics of the battery to minimize the impact of overcharging on battery life and reduce unnecessary energy loss; the specific values ​​are not limited in this application.

[0057] For example, when the vehicle controller 50 detects that the battery 10's charge level is lower than a preset low charge threshold, it indicates that the battery 10 needs charging. Based on this charging requirement, the vehicle controller 50 outputs a high voltage that controls the closing of the switch structure 40. When the control terminal 401 receives the high voltage, it closes the switch structure 40, causing the DC-DC converter 20 to charge the battery 10. When the vehicle controller 50 detects that the battery 10's charge level is higher than the high charge threshold, the battery 10 no longer needs charging. The vehicle controller 50 outputs a low voltage that controls the opening of the switch structure 40. When the control terminal 401 receives the low voltage, it opens the switch structure 40, causing the DC-DC converter 20 to stop charging the battery.

[0058] The battery charging and discharging control circuit provided in this application includes a battery, a DC-DC converter, a switching structure, and a vehicle controller. The switching structure includes a control terminal. The battery is connected to the switching structure, and the switching structure is connected to the DC-DC converter. The input terminal of the vehicle controller is connected to the battery, and the output terminal of the vehicle controller is connected to the control terminal. The vehicle controller determines the output voltage based on the battery's charge level and outputs the output voltage to the control terminal. The control terminal closes or opens the switching structure according to the output voltage, so that the DC-DC converter charges or does not charge the battery. This application completes the charging and discharging control by outputting a voltage corresponding to whether charging is enabled by the vehicle controller and then closing or opening the switching structure by the control terminal. This achieves timely charging and discharging of the battery based on its charge level, improving control accuracy and effectiveness. Simultaneously, it avoids problems caused by insufficient charge or overcharging, thus solving the problem of how to control battery charging and discharging.

[0059] Figure 3 This is a schematic diagram of another battery charging and discharging control circuit provided in an embodiment of this application.

[0060] like Figure 3 As shown, the battery charging and discharging control circuit provided in this application embodiment includes: a battery 10, a DC-DC converter 20, a switching structure 40, and a vehicle controller 50; the switching structure 40 includes a control terminal 401; wherein, the battery 10 is connected to the switching structure 40, and the switching structure 40 is connected to the DC-DC converter 20; the input terminal of the vehicle controller 50 is connected to the battery 10, and the output terminal of the vehicle controller 50 is connected to the control terminal 401; the vehicle controller 50 is used to determine the output voltage based on the charge of the battery 10, and output the output voltage to the control terminal 401; the control terminal 401 is used to close or open the switching structure 40 according to the output voltage, so that the DC-DC converter 20 charges or does not charge the battery 10.

[0061] For example, after the vehicle is powered on, the vehicle controller 50 determines whether charging is needed based on the charge level of the battery 10, and then determines and outputs the corresponding voltage. The control terminal 401 closes or opens the switch structure 40 based on the output voltage of the vehicle controller 50, so that the DC converter 20 charges or does not charge the battery 10, thereby realizing the charging and discharging control of the battery.

[0062] In one example, the switch structure 40 includes a diode 41 and a switching element 42. The switching element 42 includes a first connection terminal 421, a second connection terminal 422, and a control terminal 401. The first connection terminal 421 is connected to the positive terminal of the diode 41 and the battery 10, while the second connection terminal 422 is connected to the negative terminal of the diode 41 and the DC-DC converter 20. The diode 41 enables unidirectional conduction from the battery 10 to the DC-DC converter 20, supplying power to the load 30 when the DC-DC converter 20 is not operating. The control terminal 401 is used to close or open the switching element 42 according to the output voltage, causing the DC-DC converter 20 to charge or not charge the battery 10.

[0063] For example, the diode has unidirectional conductivity. In this application, a diode 41 is provided in the switch structure 40 to enable unidirectional conduction from the battery 10 to the DC-DC converter 20, so that the battery 10 can supply power to the load 30 when the DC-DC converter 20 is not working.

[0064] In addition, the switch structure 40 also includes a switch element 42, which is closed or opened by the control terminal 401 to realize the charging and discharging control of the battery 10.

[0065] In one example, the switching element includes a MOSFET, with the source of the MOSFET being the first connection terminal 421, the drain of the MOSFET being the second connection terminal 422, and the gate of the MOSFET being the control terminal 401.

[0066] For example, after the vehicle controller 50 determines and outputs the voltage, the MOSFET determines whether the source and drain are conducting based on the magnitude of the gate and source voltages. When the gate voltage of the MOSFET is higher than the source voltage, the source and drain of the MOSFET are conducting, and the low-voltage terminal voltage of the DC-DC converter 20 is higher than the voltage of the battery 10, so the DC-DC converter 20 charges the battery 10. When the gate voltage of the MOSFET is lower than the source voltage, the source and drain of the MOSFET are not conducting, and the DC-DC converter 20 and the battery 10 are only connected through diode 41. The battery 10 supplies power to the power supply load 30 through diode 41, and the DC-DC converter 20 stops charging the battery 10.

[0067] Among them, MOSFETs have advantages such as good real-time response and long lifespan, which can improve the control effect of the entire battery charging and discharging control circuit.

[0068] In one example, the vehicle controller 50 includes a microcontroller 51, an amplifier circuit 52, and a comparator structure 53.

[0069] The microcontroller unit 51 is connected to the input terminal of the amplifier circuit 52, the input terminal of the amplifier circuit 52 is connected to the battery 10, the output terminal of the amplifier circuit 52 is connected to the positive input terminal of the comparator structure 53, and the negative input terminal of the comparator structure 53 is connected to the battery 10; the output terminal of the comparator structure 53 is connected to the control terminal 401.

[0070] The microcontroller unit 51 is used to determine the control signal based on the power of the battery 10 and to provide the control signal to the amplifier circuit 52.

[0071] The amplifier circuit 52 is used to determine the output voltage of the amplifier circuit 52 according to the control signal, and to provide the output voltage to the positive input terminal of the comparator structure 53.

[0072] The battery 10 is used to provide a negative input voltage to the negative input terminal of the comparator structure 53.

[0073] Comparison structure 53 is used to determine and output the output voltage based on the output terminal voltage and the negative input voltage.

[0074] For example, the microcontroller unit 51 in the vehicle controller 50 determines whether the battery 10 needs charging based on its charge level. If charging is required, it sends a charging control signal to the amplifier circuit 52; if charging is not required, it sends a non-charging control signal. This control signal can be a PWM control signal, designed to control the output voltage of the amplifier circuit 52. Upon receiving the control signal, the amplifier circuit 52 adjusts its input voltage to stabilize the output voltage at the level corresponding to the control signal, and provides the output voltage to the positive input terminal of the comparator structure 53. Simultaneously, the battery 10 provides a negative input voltage to the negative input terminal of the comparator structure 53. The comparator structure 53 then determines and outputs the output voltage based on the output voltage and the negative input voltage.

[0075] The output voltage provided by the amplifier circuit 52 can be used as the reference voltage, and the negative input voltage provided by the battery 10 can be used as the comparison voltage. The comparison structure 53 divides the reference voltage and the negative input voltage, and then compares the magnitudes of the divided voltages. If the divided reference voltage is greater than the divided negative input voltage, the output voltage is determined and output as the reference voltage; if the divided reference voltage is less than the divided negative input voltage, the comparison structure 53 is grounded, meaning the output voltage is 0.

[0076] To ensure that the gate voltage of the MOSFET is greater than the source voltage when charging is required, thus enabling the source and drain of the MOSFET to conduct, the reference voltage for charging can be set as the sum of the low-voltage terminal voltage of the DC-DC converter 20, the voltage difference between the gate and source when the source and drain of the MOSFET are conducting, and a preset voltage difference value. The voltage difference between the gate and source when the source and drain of the MOSFET are conducting is an inherent characteristic of the MOSFET. The preset voltage difference value is to ensure that the voltage at the positive input terminal of the comparator structure 53 is lower than the negative input voltage when the battery stops charging; this application does not impose specific limitations on the magnitude of the preset voltage difference value. For example, when the battery charge of 10 is lower than a preset low charge threshold, the microcontroller unit 51 outputs a PWM control signal indicating that charging is required. The amplifier circuit 52, based on this control signal, stabilizes the output voltage of the amplifier circuit 52 at the reference voltage required for charging. Then, amplifier circuit 52 sends the reference voltage to the positive input terminal of comparator structure 53; simultaneously, comparator structure 53 also receives the negative input voltage from the battery; after comparator structure 53 divides the reference voltage and the negative input voltage, the comparison result should be that the divided reference voltage is greater than the divided negative input voltage, and the output voltage of comparator structure 53 is the reference voltage. At this time, the gate of the MOSFET controls the source and drain to conduct, enabling DC-DC converter 20 to charge battery 10.

[0077] To ensure that the gate voltage of the MOSFET is lower than the source voltage when charging stops, thus preventing the source and drain of the MOSFET from conducting, the reference voltage for stopping charging can be set as the sum of the voltage of the battery 10 and a preset voltage difference value. For example, when the charge of the battery 10 exceeds a preset high charge threshold, the microcontroller 51 outputs a PWM control signal to stop charging. Based on this control signal, the amplifier circuit 52 stabilizes its output voltage at the reference voltage at the time of stopping charging. Then, the amplifier circuit 52 sends this reference voltage to the positive input terminal of the comparator structure 53. Simultaneously, the comparator structure 53 also receives the negative input voltage from the battery. After the comparator structure 53 divides the reference voltage and the negative input voltage, the comparison result should be that the divided reference voltage is less than the divided negative input voltage. The comparator structure 53 is then grounded, meaning its output voltage is 0. At this time, the gate of the MOSFET controls the source and drain to not conduct, causing the DC-DC converter 20 to stop charging the battery 10.

[0078] This application does not impose any restrictions on how the amplifier circuit 52 determines its output voltage based on the control signal. In one example, the amplifier circuit 52 includes a transistor, with the base of the transistor being the input terminal of the amplifier circuit 52, the collector of the transistor being the output terminal of the amplifier circuit 52, and the emitter of the transistor being grounded.

[0079] For example, the transistor can control the output voltage to stabilize at the reference reference voltage when charging is required, according to the PWM control signal provided by the microcontroller 51 for charging; or it can control the output voltage to stabilize at the reference reference voltage when charging is stopped, according to the PWM control signal provided by the microcontroller 51 for stopping charging.

[0080] For example, to improve the stability of the output voltage of amplifier circuit 52, a capacitor can be included in amplifier circuit 52. One end of the capacitor is connected to the output terminal of amplifier circuit 52, and the other end is grounded.

[0081] In one example, the comparator structure 53 includes a comparator 531, a positive voltage divider resistor 532, and a negative voltage divider resistor 533.

[0082] One end of the positive voltage divider resistor 532 is connected to the output terminal of the amplifier circuit 52, and the other end of the positive voltage divider resistor 532 is connected to the positive input terminal of the comparator 531. One end of the negative voltage divider resistor 533 is connected to the battery 10, and the other end of the negative voltage divider resistor 533 is connected to the negative input terminal of the comparator 531. The output terminal of the comparator 531 is connected to the control terminal 401.

[0083] The positive voltage divider resistor 532 is used to divide the output voltage and provide the divided output voltage to the positive input terminal of the comparator 531.

[0084] The negative voltage divider resistor 533 is used to divide the negative input voltage and provide the divided negative input voltage to the negative input terminal of the comparator 531.

[0085] Comparator 531 is used to compare the output voltage after voltage division with the negative input voltage after voltage division, and to determine and output the output voltage.

[0086] For example, the output voltage provided by the amplifier circuit 52 can be used as a reference voltage, and the negative input voltage provided by the battery 10 can be used as a comparison voltage. The positive voltage divider resistor 532 divides the reference voltage and inputs it to the positive input terminal of the comparator 531; the negative voltage divider resistor 533 divides the negative input voltage and inputs it to the negative input terminal of the comparator 531. Then, the comparator 531 compares the voltages at the positive and negative input terminals. If the voltage at the positive input terminal is greater than the voltage at the negative input terminal, the comparator 531 outputs a reference voltage; the gate of the MOSFET controls the source and drain to conduct, causing the DC-DC converter 20 to charge the battery 10. If the voltage at the positive input terminal is less than the voltage at the negative input terminal, the comparator 531 is grounded, i.e., the output voltage is 0; the gate of the MOSFET controls the source and drain to not conduct, causing the DC-DC converter 20 to stop charging the battery 10.

[0087] In order to ensure that the reference voltage at the positive input terminal of comparator 531 is less than the voltage at the negative input terminal when the battery 10 stops charging, and that the reference voltage at the positive input terminal of comparator 531 is greater than the voltage at the negative input terminal when the battery 10 is charging, the positive voltage divider resistor needs to be set to be greater than the negative voltage divider resistor.

[0088] For example, Figure 4 This is a schematic diagram of a battery charging and discharging control logic provided in an embodiment of this application.

[0089] like Figure 4 As shown, after the high voltage is applied, the vehicle controller obtains the battery's charge level and determines whether the battery needs charging based on the charge level. If charging is required, the control amplifier circuit outputs the required charging voltage, the comparator outputs the amplifier circuit's output voltage, the source and drain of the MOSFET are connected, and the DC-DC converter charges the battery. If charging is not required, the control amplifier circuit outputs the required charging voltage, the comparator outputs the ground voltage, the source and drain of the MOSFET are not connected, and the DC-DC converter stops charging the battery.

[0090] For example, combined Figure 3 and Figure 4 After the high voltage is applied, the microcontroller unit 51 in the vehicle controller 50 determines whether the battery 10 needs to be charged based on its charge level. If the charge level of the battery 10 is lower than the low charge threshold, the microcontroller unit 51 outputs a PWM control signal indicating that charging is required, which controls the transistor in the amplifier circuit 52 to stabilize the output voltage of the amplifier circuit 52 at V. -DCDC +10V+V ChrgOffset , where V -DCDC This is the low-voltage side voltage of DC-DC converter 20; 10V is the gate-source voltage difference when the source and drain of the MOSFET are turned on, which is an inherent characteristic of the MOSFET; V ChrgOffset The purpose of the preset voltage difference is to ensure that when battery 10 stops charging, the reference voltage at the positive input terminal of comparator 531 is lower than the voltage at the negative input terminal. Figure 3 As shown, the voltage at the positive input terminal of comparator 531 is the voltage at point D after being divided by the positive voltage divider resistor 532, which is also the voltage V after voltage division. -DCDC +10V+V ChrgOffset The voltage at the negative input terminal of comparator 531 is the voltage at point A after being divided by the negative voltage divider resistor 533, which is also the battery voltage V after voltage division. -BattBecause the output voltage of the amplifier circuit is higher than the low-voltage side voltage of the DC-DC converter and higher than the voltage of battery 10, and the positive voltage divider resistor 532 is greater than the negative voltage divider resistor 533, the voltage at the low-voltage side of the positive input of comparator 531 is higher than the voltage at the negative input. Therefore, the output voltage of the amplifier circuit, i.e., V, is calculated using comparator 531. -DCDC +10V+V ChrgOffset Therefore, the gate voltage of the MOSFET is V. -DCDC +10V+V ChrgOffset Therefore, the source and drain of the MOSFET are connected, and at this time, the DC-DC converter 20 charges the battery 10.

[0091] When the battery charge of 10 exceeds the high charge threshold, the microcontroller unit 51 outputs a PWM control signal to stop charging, controlling the transistor in the amplifier circuit 52 to stabilize the output voltage of the amplifier circuit 52 at: V _Batt +D ChrgOffset , where V _Batt The voltage of battery 10, D ChrgOffset For the preset pressure difference, D ChrgOffset With V ChrgOffset The values ​​can be the same or different, without restriction. The voltage at the positive input terminal of comparator 531 is the voltage at point D after being divided by the positive voltage divider resistor 532, that is, the voltage V after voltage division. _Batt +D ChrgOffset The voltage at the negative input terminal of comparator 531 is the voltage at point A after being divided by the negative voltage divider resistor 533, which is also the battery voltage V after voltage division. _Batt At this time, the voltage at the positive input terminal of comparator 531 is lower than the voltage at the negative input terminal, and comparator 531 outputs a ground voltage. That is, at this time, the gate of the MOSFET is grounded, the source and drain of the MOSFET are not connected, and the DC-DC converter 20 stops charging the battery 10.

[0092] The battery charging and discharging control circuit provided in this application embodiment incorporates a diode in the switching structure, enabling unidirectional conduction from the battery to the DC-DC converter. This allows the battery to power the load when the DC-DC converter is not operating. Furthermore, the switching element is a MOSFET, which has advantages such as good real-time response and long lifespan, thus improving the overall control effect of the battery charging and discharging control circuit. In addition, the charging and discharging control also reduces the impact of the charging and discharging process on the battery lifespan, extending the lifespan of various electronic devices.

[0093] In addition, this application also provides a battery charging and discharging control device, which includes the battery charging and discharging control circuit provided in any of the above embodiments.

[0094] Furthermore, this application also provides an automobile, which includes a battery charging and discharging control circuit as provided in any of the above embodiments.

[0095] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0096] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A battery charging and discharging control circuit, characterized in that, The control circuit includes: a battery, a DC-DC converter, a switching structure, and a vehicle controller; the switching structure includes a control terminal. The battery is connected to the switch structure, and the switch structure is connected to the DC-DC converter; the input terminal of the vehicle controller is connected to the battery, and the output terminal of the vehicle controller is connected to the control terminal. The vehicle controller is used to determine the output voltage based on the battery charge and output the output voltage to the control terminal. The control terminal is used to close the switching structure according to the output voltage so that the DC converter charges the battery, or to open the switching structure according to the output voltage so that the DC converter does not charge the battery; The vehicle controller includes a microcontroller unit, an amplifier circuit, and a comparator structure; the amplifier circuit includes a transistor; the microcontroller unit is connected to the base of the transistor, the input terminal of the amplifier circuit is connected to the battery, the output terminal of the amplifier circuit is connected to the positive input terminal of the comparator structure, the negative input terminal of the comparator structure is connected to the battery, and the output terminal of the comparator structure is connected to the control terminal. The microcontroller unit is used to determine the control signal based on the battery charge and to provide the control signal to the amplifier circuit. The amplifier circuit is used to determine the output voltage of the amplifier circuit according to the control signal, and to provide the output voltage to the positive input terminal of the comparator structure. The battery is used to provide a negative input voltage to the negative input terminal of the comparator structure; The comparison structure is used to determine and output the output voltage based on the output terminal voltage and the negative input voltage.

2. The control circuit according to claim 1, characterized in that, The switching structure includes a diode and a switching element, the switching element including a first connection terminal, a second connection terminal, and a control terminal; The first connection terminal is connected to the positive terminal of the diode and the battery, and the second connection terminal is connected to the negative terminal of the diode and the DC-DC converter. The diode is used to enable unidirectional conduction from the battery to the DC-DC converter, so as to supply power to the load when the DC-DC converter is not working; The control terminal is used to close or open the switching element according to the output voltage, so that the DC converter charges or does not charge the battery.

3. The control circuit according to claim 2, characterized in that, The switching element includes a MOSFET, the source of which is the first connection terminal, the drain of which is the second connection terminal, and the gate of which is the control terminal.

4. The control circuit according to claim 1, characterized in that, The comparison structure includes a comparator, a positive voltage divider resistor, and a negative voltage divider resistor; One end of the positive voltage divider resistor is connected to the output terminal of the amplifier circuit, and the other end of the positive voltage divider resistor is connected to the positive input terminal of the comparator. One end of the negative voltage divider resistor is connected to the battery, and the other end of the negative voltage divider resistor is connected to the negative input terminal of the comparator. The output terminal of the comparator is connected to the control terminal. The positive voltage divider resistor is used to divide the output voltage and provide the divided output voltage to the positive input terminal of the comparator. The negative voltage divider resistor is used to divide the negative input voltage and provide the divided negative input voltage to the negative input terminal of the comparator. The comparator is used to compare the output voltage after voltage division with the negative input voltage after voltage division, and to determine and output the output voltage.

5. The control circuit according to claim 4, characterized in that, The positive voltage divider resistor is greater than the negative voltage divider resistor.

6. The control circuit according to claim 1, characterized in that, The base of the transistor is the input terminal of the amplifier circuit, the collector of the transistor is the output terminal of the amplifier circuit, and the emitter of the transistor is grounded.

7. The control circuit according to any one of claims 1-6, characterized in that, The control circuit also includes a battery monitoring sensor connected to the battery. The battery monitoring sensor is used to monitor the battery's charge level and provide the battery's charge level information to the vehicle controller.

8. A battery charging and discharging control device, characterized in that, Includes the control circuit as described in any one of claims 1-7.

9. A car, characterized in that, The vehicle includes a control circuit as described in any one of claims 1-7.

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