Hybrid power system and vehicle comprising same

Abstract

The invention relates to a hybrid power system and a vehicle. The hybrid power system comprises a first storage battery; a motor; the direct current converter is electrically coupled with the first storage battery and the motor; and a controller communicatively coupled with the DC converter and the electric machine and configured to: send a boost control signal to the DC converter to switch the DC converter to a boost mode; in response to detecting that the voltage output by the DC converter in the boost mode exceeds a threshold voltage, indicating that the motor operates in a power generation mode; and sending a step-down control signal to the direct current converter based on the fact that the voltage output by the motor in the power generation mode is maintained at the rated voltage of the motor, the DC converter is switched from the boost mode to a buck mode to supply power generated by the motor in the power generation mode to the first battery.

Description

Technical Field

[0001] The present application relates to the field of battery management, and more specifically, to a hybrid system and a vehicle comprising the same. Background Art

[0002] A hybrid vehicle may have a lower voltage (e.g., 12V) and a higher voltage (e.g., 48V or higher) battery system to respectively power, for example, vehicle drive and cabin loads. However, in a situation where the higher voltage battery system cannot be used (e.g., battery failure), it may be difficult for the higher voltage battery to participate in vehicle drive and cannot charge, for example, the lower voltage battery.

[0003] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present application, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0004] According to one aspect of the present application, a hybrid system is provided, which includes: a first battery; a motor; a DC converter electrically coupled to the first battery and the motor; and a controller communicatively coupled to the DC converter and the motor and configured to perform the following operations: sending a boost control signal to the DC converter to switch the DC converter to a boost mode; in response to detecting that a voltage output by the DC converter in the boost mode exceeds a threshold voltage, indicating that the motor operates in a power generation mode; and based on detecting that a voltage output by the motor in the power generation mode is maintained at a rated voltage of the motor, sending a step-down control signal to the DC converter so that the DC converter switches from the boost mode to the step-down mode to supply the first battery with the power generated by the motor in the power generation mode.

[0005] In one or more embodiments of the present application, optionally, the hybrid system further includes: a second battery coupled to the DC converter via a contactor, wherein the controller is configured to decouple the DC converter from the second battery before performing the operation.

[0006] In one or more embodiments of the present application, optionally, the controller is configured to: disconnect the contactor to decouple the DC converter from the second battery based on detecting that the power level of the second battery is lower than a threshold power level.

[0007] In one or more embodiments of the present application, optionally, the controller is configured to: disconnect the contactor to decouple the DC converter from the second battery based on detecting that the temperature of the second battery is lower than a threshold temperature.

[0008] In one or more embodiments of the present application, optionally, the rated voltage of the second battery is greater than the rated voltage of the first battery.

[0009] In one or more embodiments of the present application, optionally, the motor includes a belt starter generator and an integrated starter generator.

[0010] In one or more embodiments of the present application, optionally, the controller is configured to: when performing the operation, disable functions corresponding to part of the load circuits in the load circuit powered by the first battery and the DC converter.

[0011] In one or more embodiments of the present application, optionally, the functions include seat heating, seat massage, and infotainment functions.

[0012] According to one aspect of the present application, a battery charging method is provided, the method comprising: sending a boost control signal to a DC converter to switch the DC converter to a boost mode, wherein the DC converter is electrically coupled to the battery and the motor; in response to detecting that the voltage output by the DC converter in the boost mode exceeds a threshold voltage, indicating that the motor is operating in a power generation mode; and based on detecting that the voltage output by the motor in the power generation mode is maintained at the rated voltage of the motor, sending a buck control signal to the DC converter so that the DC converter switches from the boost mode to the buck mode to supply the battery with the power generated by the motor in the power generation mode.

[0013] According to one aspect of the present application, a vehicle is provided, the vehicle comprising any one of the hybrid systems described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The above and other features, aspects and advantages of the present application will become better understood when reading the following detailed description with reference to the accompanying drawings, in which the same or similar elements are represented by the same reference numerals. It should be noted that the drawings in the present application are only schematic and may not be drawn to scale or specific numbers. In the drawings:

[0015] Figure 1 The topology of a hybrid system according to one or more embodiments of the present application is shown;

[0016] Figure 2 A method for charging a vehicle battery according to one or more embodiments of the present application is shown; and

[0017] Figure 3 A schematic block diagram of a computer system. DETAILED DESCRIPTION

[0018] The present application is described more fully below with reference to the accompanying drawings in which the illustrative embodiments of the present application are illustrated. In the following detailed description of the embodiments, many specific details are set forth in order to provide a more thorough understanding of the present application's disclosure. However, in one or more embodiments, well-known features are not described in detail to avoid making the description unnecessarily complicated. Where applicable, the embodiments of the present application and the features in the embodiments can also be combined with each other. As used herein, the term "coupling" means being directly connected to one or more components or circuits or being connected through one or more intermediate components or circuits. In some examples, known circuits and devices are shown in block diagram form to avoid making the present disclosure complicated.

[0019] In the present application, terms such as "comprises", "includes", "has" and the like indicate that in addition to the units and steps directly and explicitly stated in the specification and claims, the technical solution described in the present application does not exclude the existence of other units and steps that are not directly or explicitly stated.

[0020] Unless otherwise specified, terms such as “first” and “second” do not indicate the order of elements in terms of time, space, size, etc., nor are they intended to limit any element to only a single element, but are merely used to distinguish between elements.

[0021] In the present application, a "DC converter" may refer to a DC element that converts a voltage in a certain range into a voltage in another range, and may have a bidirectional DC-DC buck / boost function, so as to realize voltage conversion between, for example, a 12V voltage domain and, for example, a 48V, 90V, etc. voltage domain. In the present application, a "motor" may refer to an electromagnetic device that provides power assistance and / or kinetic energy recovery for an engine, which has an electric mode (for example, operates by obtaining power from a battery) and a power generation mode (for example, enters a self-excitation state and provides power to the outside of the motor), and when it starts to generate power, the battery may provide an excitation current and when the generated voltage reaches a threshold voltage (for example, the rated voltage of the battery), it may be converted to self-excitation. A "controller" may refer to a hybrid control unit for the hybrid system proposed in the present application, which may be, for example, a microprocessor, a microcontroller, a digital signal processor, an application-specific integrated circuit, a field programmable gate array, an electronic control unit (ECU) or any other suitable computing device or one or more combinations thereof. In addition, the motors, engines, DC converters, controllers, etc. described in this application may all have communication functions (e.g., through their respective integrated signal transceivers) and may establish communication with each other (e.g., based on the controller area network (CAN) protocol), unless otherwise explicitly stated. In this article, "disconnect" and "close" are used to describe the on-off state of the contactor. "Disconnecting" a contactor means changing the contact of the contactor from a closed state to a separated state so that the circuit in which the contactor is located is disconnected. "Closing" a contactor means changing the contact of the contactor from a separated state to a closed state so that the circuit in which the contactor is located is closed.

[0022] Figure 1 The topology of the hybrid system 100 according to one or more embodiments of the present application is shown, which includes a controller 110, a DC converter 120, a motor 130, a first battery 140, and a second battery 150. It should be noted that in order not to make the present disclosure complicated and difficult to understand, Figure 1 Some well-known components (such as an inverter coupled between the motor 130 and a battery (such as the second battery 150) and / or the DC converter 120) may not be shown, but it is not necessary for those skilled in the art to provide such specific details to understand the embodiments of the present application.

[0023] In the hybrid system 100 of the vehicle, the controller 110 is communicatively coupled to a DC converter 120 and an electric machine 130 coupled to an engine (not shown) via a belt or gears (e.g., a gear set), such as a belt starter generator (BSG) and an integrated starter generator (ISG). The DC converter 120 is connected to the engine via, for example, a power harness ( Figure 1The first battery 140 is connected to the second battery 150 (shown as a thicker line in FIG). The first battery 140 can provide power for one or more relatively low-voltage systems in the vehicle (such as seat heating and massage system, infotainment system, door and window control system, airbag system, start-stop system, etc.), and can be, for example, a lead-acid battery with a rated voltage of 12V. Compared with the first battery 140, the rated voltage and capacity of the second battery 150 can be larger (for example, 48V, 90V, etc.) to provide additional power assistance for the driving of the vehicle.

[0024] In some cases, the second battery 150 may be unavailable, so that the controller 110 performs some high-priority operations to avoid causing more serious impacts on the second battery 150 and / or the entire hybrid system 100. For example, when a battery fails (for example, the corresponding battery management system reports to the controller 110 in the case of abnormal voltage, current and power, electrostatic discharge, etc.), the controller 110 receives a signal indicating fault information (for example, a fault code), and then disconnects the contactor (not shown) connecting the second battery 150 and the DC converter 120 according to the fault information, so that the second battery 150 is decoupled from the hybrid system 100. Or, for example, when it is detected that the temperature of the second battery 150 is lower than the minimum operating temperature (for example, -30°C), the controller 110 does not close the above contactor but maintains it open to avoid connecting the second battery 150 to its corresponding voltage domain.

[0025] In the above situation or, for example, when the contactor connecting the second battery 150 and the DC converter 120 fails and cannot be closed, the first battery 140 in the vehicle will not be powered by the second battery 150 and will gradually run out of power, causing the vehicle systems such as the instrument panel to fail to operate, and even causing the vehicle to fail to start, because the vehicle's engine ignition function may still be in the lower voltage domain of the first battery 140 rather than the higher voltage domain of the second battery 150. In such hybrid systems, for cost and feasibility considerations, the output voltage of the motor 130 in the vehicle coupled to the engine to provide power assistance and / or kinetic energy recovery (for example, in power generation mode) only matches the voltage domain of the second battery 150 rather than the lower voltage domain of the first battery 140, resulting in the motor 130 being unable to power the first battery 140 via the engine drive when the second battery 150 is unavailable.

[0026] In some embodiments, the motor 130 can be powered by the first battery 140 by switching the working mode of the DC converter 120. Specifically, when the second battery 150 is unavailable, the controller 110 can send a digital control signal including an instruction to enter the boost mode to the DC converter 120 (for example, to a digital controller integrated in the DC converter 120), so that the DC converter 120 switches from the buck mode that originally converts the voltage of the second battery 150 into the voltage of the first battery 140 to the boost mode (at the same time, the input and output directions of the DC converter 120 are interchanged) to provide an excitation current to the motor 130 electrically coupled to the DC converter 120. Next, when the controller 110 that monitors the voltage on the power harness coupled to the DC converter 120 detects that, for example, the voltage on the power harness connected to the corresponding output end of the DC converter 120 in the boost / buck mode rises to a threshold voltage (for example, the voltage when the motor 130 changes from external excitation to self-excitation in the power generation mode), the controller 110 may send a control signal containing an instruction to keep the motor 130 operating in the power generation mode to the motor 130 (for example, to a microcontroller with communication function integrated in the motor 130), so that the terminal voltage of the motor 130 gradually increases to the rated output voltage of the motor 130 in the power generation mode due to the increase in engine speed.

[0027] Next, the controller 110, which monitors the voltage output by the motor 130 in the power generation mode (e.g., via a rectifier that can be coupled to the motor 130), can control the DC converter 120 to switch to the buck mode to supply power to the first battery 140 in response to detecting that the voltage output by the motor 130 in the power generation mode is maintained at the rated output voltage of the motor 130. Specifically, the controller 110 can send a digital control signal including an instruction to enter the buck mode to the DC converter 120, switching the DC converter 120 from the previous boost mode back to the buck mode (while causing the input and output directions of the DC converter 120 to be interchanged again), so that the output of the motor 130 in the power generation mode (through, for example, a rectifier) ​​is provided to the first battery 140 through the DC converter 120, for example, through a power electronic switch that is closed after the DC converter 120 switches back to the buck mode, to charge the first battery 140. Through the above operation, the operation of the hybrid system 100 can be maintained when the second battery 150, which has a larger capacity and a rated voltage than the first battery 140, is not available.

[0028] In some embodiments, the above Figure 1The hybrid system 100 can only maintain functions related to vehicle driving and safety (such as engine ignition, airbags, etc.) and disable some comfort functions to avoid fluctuations in the output voltage of the motor 130 that may be caused by the load when the second battery 150 is unavailable. Specifically, the controller 110 can disconnect the load circuit for realizing comfort functions (such as seat heating, seat massage, etc.) powered by the first battery 140 and the DC converter 120 from the first battery 140 and the DC converter 120, for example, by disconnecting a power semiconductor switch such as a MOSFET. As a result, the hybrid system 100 can ensure safe driving of the vehicle by preferentially providing the power generated by the motor 130 to part of the load circuits powered by the first battery 140 and the DC converter 120.

[0029] Figure 2 A vehicle battery charging method 200 according to one or more embodiments of the present application is shown. The method 200 includes steps 210, 220, and 230 and can be performed by a vehicle's hybrid system (e.g. Figure 1 The hybrid system 100 is implemented, wherein the hybrid system may include a first battery, a motor, a DC converter electrically coupled to the first battery and the motor, and a controller, which is communicatively coupled to the DC converter and the motor. In step 210, the controller of the hybrid system sends a boost control signal to the DC converter to switch the DC converter from a buck mode to a boost mode. In step 220, in response to detecting that the voltage output by the DC converter in the boost mode exceeds a threshold voltage, the controller controls the motor to operate in a power generation mode. In step 230, based on detecting that the voltage output by the motor in the power generation mode is maintained at the rated voltage of the motor, the controller sends a buck control signal to the DC converter so that the DC converter switches from the boost mode back to the buck mode to supply the first battery with the power generated by the motor.

[0030] Although Figure 2 The steps in the embodiment are presented and described sequentially, but a person of ordinary skill will appreciate that some or all of the steps may be combined or omitted, and some or all of the steps may be performed in parallel, and additional steps may be further performed. Therefore, the scope of the present disclosure should not be considered to be limited to Figure 2 A specific arrangement of the steps shown in .

[0031] Figure 3 is a schematic block diagram of a computer system. Figure 3As shown, the computer system 300 includes at least one memory 310 (e.g., a non-volatile memory such as a flash memory, a ROM, a hard disk drive, a magnetic disk, an optical disk, etc.), at least one processor 320, and a computer program 330. The memory 310 stores the computer program 330 executable by the processor 320. The processor 330 is configured to run the computer program 330 stored on the memory 310. By running the computer program stored on one or more memories on one or more processors (e.g., a method in which multiple processors cooperate to run the computer program or a method in which a single processor runs the computer program alone), the above-mentioned method can be realized by using Figure 2 One or more steps or operations included in the method.

[0032] According to another aspect of the present application, a computer-readable storage medium is provided on which instructions are stored. When the instructions are executed by a processor, the above-mentioned Figure 2 One or more steps or operations included in the method.

[0033] According to another aspect of the present application, a computer program product is also provided, the computer program product comprising computer instructions, the computer instructions can be executed by a processor to achieve the above Figure 2 One or more steps or operations included in the method.

[0034] The processor referred to in this application may be an integrated circuit chip having the ability to process signals. Figure 2 One or more steps or operations included in the method may be performed by an integrated logic circuit of hardware in a processor or by instructions in the form of software. The processor may be a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component. The general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc.

[0035] The computer-readable storage medium referred to in the present application includes various types of computer storage media, which can be any available medium that a general or special-purpose computer can access. For example, a computer-readable storage medium can include RAM, ROM, EPROM, E2PROM, register, hard disk, removable disk, CD-ROM or other optical disk storage, disk storage or other magnetic storage device, or can be used to carry or store a desired program code unit with an instruction or data structure form and can be accessed by a general or special-purpose computer, or a general or special-purpose processor. Any other temporary or non-temporary medium. The above combination should also be included in the protection scope of the computer-readable storage medium. An exemplary storage medium is coupled to a processor so that the processor can read and write information from / to the storage medium. In an alternative, a storage medium can be integrated into a processor.

[0036] It should be noted that the embodiments described in this application are intended to make the disclosure herein comprehensive and complete, and are not intended to limit the scope of the claimed subject matter. Those skilled in the art may think of other feasible changes or replacements based on the technical scope disclosed in this application, and such changes or replacements are all included in the protection scope of this application. Those skilled in the art will know that the above description and examples are provided only for the convenience of explanation and example, and the proposed description and examples are not intended to cover all aspects of the application or limit the application to the disclosed precise form. The technical solutions recorded in this application can be implemented in different forms without departing from the spirit and scope of the application.

Claims

1. A hybrid system, comprising: First battery; Motor; a DC converter electrically coupled to the first battery and the motor; as well as A controller is communicatively coupled to the DC converter and the motor and is configured to: Sending a boost control signal to the DC converter to switch the DC converter to a boost mode; In response to detecting that the voltage output by the DC converter in the boost mode exceeds a threshold voltage, instructing the motor to operate in a power generation mode; and Based on detecting that the voltage output by the motor in the power generation mode is maintained at the rated voltage of the motor, a step-down control signal is sent to the DC converter, so that the DC converter switches from the boost mode to the step-down mode to supply the first battery with the power generated by the motor in the power generation mode.

2. The hybrid system according to claim 1, further comprising: A second storage battery is coupled to the DC converter via a contactor, wherein the controller is configured to decouple the DC converter from the second storage battery before performing the operation.

3. The hybrid system according to claim 2, wherein: The controller is configured to open the contactor to decouple the DC converter from the second battery based on detecting that the charge level of the second battery is lower than a threshold charge level.

4. The hybrid system according to claim 2, wherein: The controller is configured to open the contactor to decouple the DC converter from the second battery based on detecting that the temperature of the second battery is lower than a threshold temperature.

5. The hybrid system according to claim 2, wherein: The rated voltage of the second battery is greater than the rated voltage of the first battery.

6. The hybrid system according to claim 1, wherein: The electric machines include belt starter generators and integrated starter generators.

7. The hybrid system according to claim 1, wherein: The controller is configured to disable functions corresponding to part of load circuits among load circuits powered by the first battery and the DC converter when performing the operation.

8. The hybrid system according to claim 7, wherein: The functions include seat heating, seat massage, and infotainment functions.

9. A method for charging a battery, the method comprising: sending a boost control signal to a DC converter to switch the DC converter to a boost mode, wherein the DC converter is electrically coupled to the battery and the motor; In response to detecting that the voltage output by the DC converter in the boost mode exceeds a threshold voltage, instructing the motor to operate in a power generation mode; and Based on detecting that the voltage output by the motor in the power generation mode is maintained at the rated voltage of the motor, a step-down control signal is sent to the DC converter, so that the DC converter switches from the boost mode to the step-down mode to supply the battery with the power generated by the motor in the power generation mode.

10. A vehicle, characterized in that: The vehicle comprises a hybrid system as claimed in any one of claims 1 to 8.

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