Electric vehicle energy management method and device

Abstract

The invention relates to an electric vehicle energy management method and device. The problem that vehicle performance and user experience are affected by insufficient output power of a battery is solved. The method comprises the steps that the driving state of a vehicle is detected; acquiring a corresponding output limiting strategy according to the driving state; and adjusting the output of the power battery according to the output limiting strategy. According to the technical scheme provided by the invention, efficient and stable vehicle energy management is realized.

Description

Technical Field

[0001] The present disclosure relates to vehicle control technology, and in particular to an electric vehicle energy management method and device. Background Art

[0002] Electric vehicles often use speed control schemes to adjust the working current of the motor to control the output power of the motor, thereby achieving control over the operation of the vehicle. During driving, the battery may be low on power or fail. At this time, in order to protect the vehicle control circuit, the output power of the battery needs to be limited, and the input power of the controller to the motor also needs to be limited.

[0003] The purpose of reducing the battery output power can be achieved by directly reducing the given speed. However, for conditions such as climbing and rapid acceleration, the battery output power usually reaches the maximum. The method of limiting the given speed will cause the battery output power to be insufficient, which will affect the vehicle performance and user experience. Summary of the invention

[0004] In order to overcome the problems existing in the related art, the present disclosure provides an electric vehicle energy management method and device. The output of the power battery is adjusted through an output limiting strategy to solve the problem that insufficient battery output power affects vehicle performance and user experience.

[0005] According to a first aspect of an embodiment of the present disclosure, there is provided an electric vehicle energy management method, comprising: Detect the driving status of the vehicle; According to the driving state, obtaining a corresponding output restriction strategy; According to the output limiting strategy, the output of the power battery is adjusted.

[0006] Furthermore, the step of detecting the driving state of the vehicle includes: Detect the vehicle and obtain any one or more of the following driving status information: Vehicle driving slope, accelerator pedal opening, and power battery status.

[0007] Furthermore, the step of acquiring a corresponding output restriction strategy according to the driving state includes: According to the driving state, an output limiting strategy to be applied is matched from at least one preset output limiting strategy, and the output limiting strategy at least includes an energy limiting coefficient.

[0008] Furthermore, the step of adjusting the output of the power battery according to the output limitation strategy includes: According to the output limiting strategy, the default given speed is adjusted to obtain the target given speed; According to the output limiting strategy, the first corresponding relationship between the current and the speed is adjusted to obtain a second corresponding relationship between the current and the speed; The output of the power battery is adjusted according to the target given speed and the second corresponding relationship.

[0009] Furthermore, the step of adjusting the default given speed according to the output limiting strategy to obtain the target given speed includes: Get the default given speed corresponding to the current accelerator pedal opening; The default given speed is multiplied by the energy limiting coefficient to obtain the target given speed.

[0010] Furthermore, the step of adjusting the first corresponding relationship between current and speed according to the output limiting strategy to obtain the second corresponding relationship between current and speed includes: The speed value corresponding to each current value in the first corresponding relationship is multiplied by the energy limiting coefficient to obtain an adjusted speed value, and the second corresponding relationship is established between each current value and the adjusted speed value.

[0011] Furthermore, the step of adjusting the output of the power battery according to the target given speed and the second corresponding relationship includes: The motor control parameters are acquired according to the target given speed, the actual speed and the speed loop limit value, and the motor output is controlled to adjust the output of the power battery, wherein the speed loop limit value is acquired according to the second corresponding relationship.

[0012] According to a second aspect of an embodiment of the present disclosure, there is provided an electric vehicle energy management device, comprising: A state detection device, used for detecting the driving state of the vehicle; A strategy acquisition module, used for acquiring a corresponding output restriction strategy according to the driving state; The output control module is used to adjust the output of the power battery according to the output limitation strategy.

[0013] Furthermore, the state detection device is used to detect the vehicle and obtain any one or more of the following driving state information: Vehicle driving slope, accelerator pedal opening, power battery status; The strategy acquisition module is used to match and obtain an applied output restriction strategy from at least one preset output restriction strategy according to the driving state, and the output restriction strategy at least includes an energy limitation coefficient.

[0014] Furthermore, the output control module includes: A target given speed acquisition submodule is used to adjust the default given speed according to the output limitation strategy to obtain the target given speed; A circuit current relationship adjustment submodule, used to adjust the first corresponding relationship between current and speed according to the output limiting strategy, and obtain a second corresponding relationship between current and speed; The output regulation submodule is used to regulate the output of the power battery according to the target given speed and the second corresponding relationship.

[0015] The technical solution provided by the embodiment of the present disclosure may include the following beneficial effects: detecting the driving state of the vehicle, then obtaining the corresponding output limitation strategy according to the driving state, and then adjusting the output of the power battery according to the output limitation strategy. For working conditions with special requirements for vehicle performance, the output of the power battery is adjusted through the output limitation strategy to achieve smooth operation of the vehicle, solving the problem that insufficient battery output power affects vehicle performance and user experience.

[0016] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0018] Figure 1 It is a schematic diagram of the principle of a speed limiting scheme.

[0019] Figure 2 It is a schematic diagram of the speed-current curve.

[0020] Figure 3 The figure is a flow chart of an electric vehicle energy management method according to an exemplary embodiment.

[0021] Figure 4 is a flow chart of yet another electric vehicle energy management method according to an exemplary embodiment.

[0022] Figure 5 is another schematic diagram of a speed-current curve according to an exemplary embodiment.

[0023] Figure 6 It is a structural schematic diagram of an electric vehicle energy management device according to an exemplary embodiment.

[0024] Figure 7 is a schematic diagram of the structure of the output control module 603 according to an exemplary embodiment.

[0025] Figure 8 is a schematic structural diagram of a target given speed acquisition submodule according to an exemplary embodiment. DETAILED DESCRIPTION

[0026] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0027] like Figure 1 The figure shows the principle of the scheme of controlling the vehicle speed by limiting the speed. When the driver releases the brake and steps on the accelerator, the microcontroller unit (MCU) calculates the given speed according to the accelerator signal. The given speed is processed by speed limit. Multiply it by the speed limit to get the final given speed Then, speed PI adjustment / PID adjustment is performed according to the given speed and the actual speed of feedback to obtain the given torque current The speed loop limit value is calculated based on the preset speed-current curve. Given torque current Input to current control and other general links to obtain , .

[0028] For situations such as hill climbing, the battery output power is usually the highest. If the given speed is limited, the battery output power cannot achieve the expected effect. For example, under normal conditions, when the accelerator pedal is pressed to the deepest point, the given speed is 4000rpm. Figure 2 Due to the limiting effect of the speed-current curve shown, the speed may stabilize at 1200rpm, at which point the battery output power may be maximum, even greater than the output power at 4000rpm on flat ground. The battery may not be able to meet the output power requirements, further affecting vehicle performance and user experience.

[0029] To solve the above problems, the embodiments of the present invention provide an electric vehicle energy management method and device. For working conditions with special requirements on vehicle performance, the output of the power battery is adjusted through the output limitation strategy to achieve smooth operation of the vehicle, solving the problem that insufficient battery output power affects vehicle performance and user experience.

[0030] An exemplary embodiment of the present disclosure provides an electric vehicle energy management method, and the process of using the method to control vehicle driving is as follows: Figure 3 As shown, including: Step 301: Detect the driving status of the vehicle.

[0031] In this step, the vehicle is detected to obtain any one or more of the following driving status information: Vehicle driving slope, accelerator pedal opening, and power battery status.

[0032] According to one embodiment, the slope information of the road where the vehicle is currently located can be collected by a slope meter, an angle sensor, etc. as the vehicle driving slope, so as to determine the driving state of the vehicle, for example, whether the vehicle is driving on a slope, the slope of the driving road, etc.

[0033] According to one embodiment, the opening of the accelerator pedal as the throttle is detected to obtain the accelerator pedal opening information. According to the accelerator pedal opening, the given speed and other information can be further determined. For example, when the driver releases the brake and steps on the accelerator pedal, the MCU calculates the default given speed according to the accelerator pedal opening information contained in the throttle signal. .

[0034] According to one implementation, power battery status information such as battery power and temperature is obtained to determine whether the output power of the power battery needs to be adjusted.

[0035] Step 302: Obtain a corresponding output restriction strategy according to the driving state.

[0036] According to one embodiment, at least one output limiting strategy can be pre-set to manage the power battery output under different conditions. For example, the temperature limiting condition reduces the output power when the temperature is too high, and does not limit the output when the temperature is normal; the slope limiting condition adjusts the output power when the vehicle is driving on a slope, and does not limit the output when driving on flat ground; the battery power limiting condition adjusts the output power when the power is low, and does not limit the output when the power is normal, etc.

[0037] In this step, according to the driving state, the output restriction strategy to be applied is matched from at least one preset output restriction strategy, and the output restriction strategy at least includes an energy restriction coefficient. For example, when the driving state indicates that the vehicle is running on a slope, the corresponding output restriction strategy is matched, and the output restriction strategy includes an energy restriction coefficient. The energy restriction coefficient can be selected and determined according to information such as slope and temperature, and is used to adjust a given speed, thereby adjusting the motor and battery output based on the given speed.

[0038] According to one embodiment, the MCU obtains the power battery status and obtains the output limiting strategy according to the power battery status. For example, the power battery status indicates that the battery power is low. At this time, the output limiting strategy obtained by matching includes the energy limiting coefficient . Energy Limitation Coefficient It can be set to 0, 0.5, and 1.0, etc., and can be set according to the operating environment and vehicle performance. When the battery power is low, the energy limit coefficient is usually less than 1.

[0039] Step 303: Adjust the output of the power battery according to the output limitation strategy.

[0040] This step is as follows Figure 4 As shown, including: Step 401: According to the output limiting strategy, the default given speed is adjusted to obtain the target given speed.

[0041] In this step, the default given speed corresponding to the current accelerator pedal opening is firstly obtained, and the correlation between the accelerator pedal opening and the default given speed can be preset.

[0042] Then, the default given speed is multiplied by the energy limitation coefficient to obtain the target given speed.

[0043] The speed given value is passed through the speed limit, and the given speed VRef is multiplied by the speed limit Kv to obtain the final given speed VDmind.

[0044] Step 402: According to the output limiting strategy, the first corresponding relationship between current and speed is adjusted to obtain a second corresponding relationship between current and speed.

[0045] The first correspondence includes multiple sets of correspondences between current and speed, specifically, the correspondence between motor current / torque current and torque speed. According to the first correspondence, the speed loop limit value can be determined. The speed loop limit value can be the current loop PI adjustment limit value, which is used to limit the working current of the motor, thereby limiting the battery output power.

[0046] In this step, the preset first correspondence between current and speed is adjusted according to the output limiting strategy. According to one embodiment, the speed value corresponding to each current value in the first correspondence can be multiplied by the energy limiting coefficient to obtain the adjusted speed value, and the second correspondence is established between each current value and the adjusted speed value.

[0047] by Figure 2 The speed-current curve shown is an example. Figure 2 The curve A in shows the first corresponding relationship. Figure 5As shown, it is a schematic diagram of the speed-current relationship of the second corresponding relationship obtained after adjusting the first corresponding relationship. Figure 5 Curve B in shows the second corresponding relationship. Figure 2 and Figure 5 In the diagram, the vertical axis represents the current value and the horizontal axis represents the speed value.

[0048] Multiplying the speed value of the horizontal axis in curve A by the energy limiting coefficient gives curve B. Taking the energy limiting coefficient as 0.5 as an example, it can be seen that the speed corresponding to the maximum current point is reduced from 800 rpm in curve A to 400 rpm in curve B.

[0049] It should be noted that there is no strict time sequence between step 401 and step 402 and they can be performed in parallel or in a certain order.

[0050] Step 403: Adjust the output of the power battery according to the target given speed and the second corresponding relationship.

[0051] In this step, the motor control parameters are obtained according to the target given speed, the actual speed and the speed loop limit value, and the motor output is controlled to adjust the output of the power battery, wherein the speed loop limit value is obtained according to the second corresponding relationship. Specifically, the current value corresponding to the target given speed can be obtained according to the second corresponding relationship as the speed loop limit value.

[0052] According to one embodiment, after determining to adjust the output of the battery through the output limitation strategy to achieve energy-limited output, the speed PI adjustment is performed according to the target given speed and the actual speed fed back. , get the new real-time current limit value .by It is input into the speed regulator as the speed loop limit value to perform speed PI regulation.

[0053] According to the default speed value The actual speed collected by the software , and the current limit value IqMaxMot, the speed loop regulator is calculated to output a given torque current , input to the current control link to obtain , , realizing closed-loop control of motor current.

[0054] An exemplary embodiment of the present disclosure also provides an electric vehicle energy management device, the structure of which is as follows: Figure 6 As shown, including: The state detection device 601 is used to detect the driving state of the vehicle; A strategy acquisition module 602, used to acquire a corresponding output restriction strategy according to the driving state; The output control module 603 is used to adjust the output of the power battery according to the output limitation strategy.

[0055] Furthermore, the state detection device 601 is used to detect the vehicle and obtain any one or more of the following driving state information: Vehicle driving slope, accelerator pedal opening, power battery status; The strategy acquisition module 602 is used to match and obtain an applied output restriction strategy from at least one preset output restriction strategy according to the driving state, and the output restriction strategy at least includes an energy restriction coefficient.

[0056] Furthermore, the structure of the output control module 603 is as follows: Figure 7 As shown, including: The target given speed acquisition submodule 701 is used to adjust the default given speed according to the output limitation strategy to acquire the target given speed; A circuit current relationship adjustment submodule 702, configured to adjust the first corresponding relationship between current and speed according to the output limiting strategy, and obtain a second corresponding relationship between current and speed; The output regulating submodule 703 is used to regulate the output of the power battery according to the target given speed and the second corresponding relationship.

[0057] Furthermore, the structure of the target given speed acquisition submodule is as follows: Figure 8 As shown, including: The default given speed acquisition submodule 801 is used to acquire the default given speed corresponding to the current accelerator pedal opening; The target given speed calculation submodule 802 is used to multiply the default given speed by the energy limit coefficient to obtain the target given speed.

[0058] Furthermore, the circuit current relationship adjustment submodule 702 is used to multiply the speed value corresponding to each current value in the first corresponding relationship by the energy limiting coefficient to obtain an adjusted speed value, and establish the second corresponding relationship between each current value and the adjusted speed value.

[0059] Furthermore, the output regulation submodule 703 is used to obtain motor control parameters according to the target given speed, actual speed and speed loop limit value, and control the motor output to adjust the output of the power battery, wherein the speed loop limit value is obtained according to the second corresponding relationship.

[0060] The above device can be integrated into the vehicle control platform, and the vehicle control platform implements the corresponding functions. Regarding the device in the above embodiment, the specific way in which each module performs the operation has been described in detail in the embodiment of the method, and will not be elaborated here.

[0061] The embodiment of the present disclosure provides an electric vehicle energy management method and device, which detects the driving state of the vehicle, then obtains the corresponding output limitation strategy according to the driving state, and then adjusts the output of the power battery according to the output limitation strategy. For working conditions with special requirements for vehicle performance, the output of the power battery is adjusted through the output limitation strategy to achieve stable operation of the vehicle, solving the problem that insufficient battery output power affects vehicle performance and user experience.

[0062] While reducing the given speed, the speed loop limit value is also adjusted, effectively realizing the control of the battery output power.

[0063] Those skilled in the art may also understand that the various illustrative logical blocks and steps listed in the embodiments of the present application may be implemented by electronic hardware, computer software, or a combination of the two. Whether such functions are implemented by hardware or software depends on the specific application and the design requirements of the entire system. Those skilled in the art may use various methods to implement the functions described for each specific application, but such implementation should not be understood as exceeding the scope of protection of the embodiments of the present application.

[0064] In addition, the word "exemplary" is used herein to indicate serving as an example, instance, or diagram. Any aspect or design described as "exemplary" in this article is not necessarily understood to be advantageous compared to other aspects or designs. On the contrary, the use of the word exemplary is intended to present concepts in a specific way. As used herein, the term "or" is intended to represent an inclusive "or" rather than an exclusive "or". That is, unless otherwise specified or clear from the context, "X applies A or B" is intended to represent any one of the natural inclusive arrangements. That is, if X applies A; X applies B; or X applies both A and B, "X applies A or B" is satisfied under any of the aforementioned examples. In addition, unless otherwise specified or clearly pointed to a singular form from the context, the articles "one" and "an" as used in this application and the appended claims are generally understood to mean "one or more".

[0065] Likewise, although the present disclosure has been shown and described with respect to one or more implementations, equivalent variations and modifications will occur to those skilled in the art after reading and understanding the specification and drawings. The present disclosure includes all such modifications and variations and is limited only by the scope of the claims. In particular, with respect to the various functions performed by the components (e.g., elements, resources, etc.) described above, unless otherwise indicated, the terms used to describe such components are intended to correspond to any component (functionally equivalent) that performs the specific functions of the described components, even if the structure is not equivalent to the disclosed structure. In addition, although specific features of the present disclosure may have been disclosed with respect to only one of several implementations, such features may be combined with one or more other features of other implementations as may be desired and beneficial to any given or specific application. In addition, with respect to "including", "having", "having", "having", or variations thereof used in a specific embodiment or claim, such terms are intended to be inclusive in a manner similar to the term "comprising".

[0066] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the following claims.

[0067] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. An electric vehicle energy management method, characterized in that: include: Detect the driving status of the vehicle; According to the driving state, obtaining a corresponding output restriction strategy; According to the output limiting strategy, the output of the power battery is adjusted.

2. The electric vehicle energy management method according to claim 1, characterized in that: The step of detecting the driving state of the vehicle comprises: Detect the vehicle and obtain any one or more of the following driving status information: Vehicle driving slope, accelerator pedal opening, and power battery status.

3. The electric vehicle energy management method according to claim 1 or 2, characterized in that: The step of acquiring a corresponding output restriction strategy according to the driving state includes: According to the driving state, an output limiting strategy to be applied is matched from at least one preset output limiting strategy, and the output limiting strategy at least includes an energy limiting coefficient.

4. The electric vehicle energy management method according to claim 3, characterized in that: The step of adjusting the output of the power battery according to the output limiting strategy includes: According to the output limiting strategy, the default given speed is adjusted to obtain the target given speed; According to the output limiting strategy, the first corresponding relationship between the current and the speed is adjusted to obtain the second corresponding relationship between the current and the speed; The output of the power battery is adjusted according to the target given speed and the second corresponding relationship.

5. The electric vehicle energy management method according to claim 4, characterized in that: The step of adjusting the default given speed according to the output limiting strategy to obtain the target given speed includes: Get the default given speed corresponding to the current accelerator pedal opening; The default given speed is multiplied by the energy limiting coefficient to obtain the target given speed.

6. The domestic energy management method for electric vehicles according to claim 4, characterized in that: The step of adjusting the first corresponding relationship between current and speed according to the output limiting strategy to obtain the second corresponding relationship between current and speed comprises: The speed value corresponding to each current value in the first corresponding relationship is multiplied by the energy limiting coefficient to obtain an adjusted speed value, and the second corresponding relationship is established between each current value and the adjusted speed value.

7. The electric vehicle energy management method according to claim 4, characterized in that: The step of adjusting the output of the power battery according to the target given speed and the second corresponding relationship comprises: The motor control parameters are acquired according to the target given speed, the actual speed and the speed loop limit value, and the motor output is controlled to adjust the output of the power battery, wherein the speed loop limit value is acquired according to the second corresponding relationship.

8. An electric vehicle energy management device, characterized in that: include: A state detection device, used for detecting the driving state of the vehicle; A strategy acquisition module, used to acquire a corresponding output restriction strategy according to the driving state; The output control module is used to adjust the output of the power battery according to the output limitation strategy.

9. The electric vehicle energy management device according to claim 8, characterized in that: The state detection device is used to detect the vehicle and obtain any one or more of the following driving state information: Vehicle driving slope, accelerator pedal opening, power battery status; The strategy acquisition module is used to match and obtain an applied output restriction strategy from at least one preset output restriction strategy according to the driving state, and the output restriction strategy at least includes an energy limitation coefficient.

10. The electric vehicle energy management device according to claim 8, characterized in that: The output control module comprises: A target given speed acquisition submodule is used to adjust the default given speed according to the output limitation strategy to obtain the target given speed; A circuit current relationship adjustment submodule, used to adjust the first corresponding relationship between current and speed according to the output limiting strategy, and obtain a second corresponding relationship between current and speed; The output regulation submodule is used to regulate the output of the power battery according to the target given speed and the second corresponding relationship.

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