Electric vehicle energy management method and device

Abstract

This disclosure relates to an electric vehicle energy management method and device. This relates to vehicle control technology and addresses the issue of insufficient battery output power impacting vehicle performance and user experience. The method includes: detecting the vehicle's driving state; obtaining a corresponding output limitation strategy based on the driving state; and adjusting the power battery's output based on the output limitation strategy. The technical solution provided by this disclosure achieves efficient and stable vehicle energy management.

Description

Technical Field

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

[0002] Electric vehicles often use speed control schemes to regulate the motor's operating current to control the motor's output power, thereby achieving operational control. During driving, battery power may be low or faulty. To protect the vehicle's control circuitry, the battery's output power needs to be limited, and the controller's input power to the motor also needs to be limited.

[0003] While directly reducing the given speed can reduce battery output power, battery output power typically reaches its maximum during hill climbing and rapid acceleration. Limiting the given speed can lead to insufficient battery output power, impacting vehicle performance and user experience. Summary of the Invention

[0004] To overcome the problems existing in the related art, the present disclosure provides an electric vehicle energy management method and device. By regulating the output of the power battery through an output limiting strategy, the problem of insufficient battery output power affecting vehicle performance and user experience is solved.

[0005] According to a first aspect of an embodiment of the present disclosure, there is provided a method for energy management of an electric vehicle, comprising:

[0006] Detecting the driving status of the vehicle;

[0007] Obtaining a corresponding output restriction strategy according to the driving state;

[0008] According to the output limiting strategy, the output of the power battery is adjusted.

[0009] Furthermore, the step of detecting the driving state of the vehicle includes:

[0010] Detect the vehicle and obtain any one or more of the following driving status information:

[0011] Vehicle driving slope, accelerator pedal opening, and power battery status.

[0012] Furthermore, the step of obtaining a corresponding output limitation strategy according to the driving state includes:

[0013] According to the driving state, an output limiting strategy is matched and applied from at least one preset output limiting strategy, and the output limiting strategy at least includes an energy limiting coefficient.

[0014] Furthermore, the step of adjusting the output of the power battery according to the output limitation strategy includes:

[0015] According to the output limiting strategy, the default given speed is adjusted to obtain the target given speed;

[0016] 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;

[0017] The output of the power battery is adjusted according to the target given speed and the second corresponding relationship.

[0018] Furthermore, the step of adjusting the default given speed according to the output limiting strategy to obtain the target given speed includes:

[0019] Get the default given speed corresponding to the current accelerator pedal opening;

[0020] The default given speed is multiplied by the energy limiting coefficient to obtain the target given speed.

[0021] Furthermore, the step of adjusting the first correspondence between current and speed according to the output limiting strategy to obtain the second correspondence between current and speed includes:

[0022] 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.

[0023] Furthermore, the step of adjusting the output of the power battery according to the target given speed and the second corresponding relationship includes:

[0024] Motor control parameters are obtained according to the target given speed, actual speed and speed loop limit value, and 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.

[0025] According to a second aspect of an embodiment of the present disclosure, there is provided an electric vehicle energy management device, comprising:

[0026] A state detection device, used for detecting the driving state of the vehicle;

[0027] A strategy acquisition module, configured to acquire a corresponding output restriction strategy according to the driving state;

[0028] The output control module is used to adjust the output of the power battery according to the output limitation strategy.

[0029] Furthermore, the state detection device is used to detect the vehicle and obtain any one or more of the following driving state information:

[0030] Vehicle driving slope, accelerator pedal opening, and power battery status;

[0031] 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 restriction coefficient.

[0032] Furthermore, the output control module includes:

[0033] 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;

[0034] a circuit current relationship adjustment submodule, 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;

[0035] An output regulation submodule is used to regulate the output of the power battery according to the target given speed and the second corresponding relationship.

[0036] The technical solutions provided by the embodiments of the present disclosure can achieve the following beneficial effects: detecting the vehicle's driving state, then obtaining a corresponding output limitation strategy based on the driving state, and then adjusting the power battery output according to the output limitation strategy. For operating conditions with special requirements for vehicle performance, the output limitation strategy can be used to adjust the power battery output to achieve smooth vehicle operation, thus resolving the problem of insufficient battery output power affecting vehicle performance and user experience.

[0037] 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 disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] 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.

[0039] Figure 1 This is a schematic diagram of the principle of a speed limit scheme.

[0040] Figure 2 It is a speed-current curve diagram.

[0041] Figure 3 The figure is a flow chart showing an energy management method for an electric vehicle according to an exemplary embodiment.

[0042] Figure 4 is a flow chart showing another electric vehicle energy management method according to an exemplary embodiment.

[0043] Figure 5 is another schematic diagram of a speed-current curve according to an exemplary embodiment.

[0044] Figure 6 The figure is a schematic structural diagram of an energy management device for an electric vehicle according to an exemplary embodiment.

[0045] Figure 7 FIG. 6 is a schematic structural diagram of the output control module 603 according to an exemplary embodiment.

[0046] Figure 8 FIG. 4 is a schematic structural diagram of a target given speed acquisition submodule according to an exemplary embodiment. DETAILED DESCRIPTION

[0047] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all possible embodiments consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present disclosure, as detailed in the appended claims.

[0048] like Figure 1 The figure shows the principle 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 based on the accelerator signal. The given speed is processed by speed limit, and the given speed is Multiply it by the speed limit to get the final given speed Then, the speed PI adjustment is performed based on the given speed and the actual speed of the feedback to obtain the given torque current. The speed loop limit value is calculated based on the preset speed-current curve. Input to current control and other general links to obtain 、 .

[0049] 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. When in hill climbing, due to the preset Figure 2Due to the limiting effect of the speed-current curve shown, the speed may stabilize at 1200 rpm, at which point the battery's output power may be maximum, even exceeding the output power at 4000 rpm on flat ground. The battery may not be able to meet the required output power, further affecting vehicle performance and user experience.

[0050] To address these issues, embodiments of the present invention provide an electric vehicle energy management method and device. For operating conditions with specific performance requirements, an output limiting strategy regulates the power battery's output to achieve smooth vehicle operation, resolving the issue of insufficient battery output power impacting vehicle performance and user experience.

[0051] An exemplary embodiment of the present disclosure provides an electric vehicle energy management method, which uses the method to control the vehicle driving process as follows: Figure 3 Shown, including:

[0052] Step 301: Detect the driving status of the vehicle.

[0053] In this step, the vehicle is detected to obtain any one or more of the following driving status information:

[0054] Vehicle driving slope, accelerator pedal opening, and power battery status.

[0055] According to one embodiment, the slope information of the road the vehicle is currently on can be collected by a gradient meter, an angle sensor, etc. as the vehicle's driving slope, thereby determining the vehicle's driving state, such as whether the vehicle is driving on a slope and the slope of the driving road.

[0056] According to one embodiment, the opening degree of the accelerator pedal, which serves as the throttle, is detected to obtain the accelerator pedal opening degree information. Based on the accelerator pedal opening degree, 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 based on the accelerator pedal opening degree information contained in the throttle signal. .

[0057] According to one embodiment, power battery status information such as battery charge level and temperature is obtained to determine whether the output power of the power battery needs to be adjusted.

[0058] Step 302: Obtain a corresponding output restriction strategy according to the driving state.

[0059] According to one embodiment, at least one output limitation strategy can be pre-set to manage the power battery output under different conditions. For example, a temperature limitation condition reduces output power when the temperature is too high and does not limit output when the temperature is normal; a slope limitation condition adjusts output power when the vehicle is driving on a slope and does not limit output when driving on flat ground; and a battery power limitation condition adjusts output power when the battery is low and does not limit output when the battery is normal.

[0060] In this step, based on the driving state, an output limitation strategy is matched and applied from at least one preset output limitation strategy. The output limitation strategy includes at least an energy limitation coefficient. For example, if the driving state indicates that the vehicle is traveling on a slope, a corresponding output limitation strategy is matched and applied, including an energy limitation coefficient. The energy limitation coefficient can be selected and determined based on information such as slope and temperature, and is used to adjust the given speed, thereby adjusting the motor and battery output based on the given speed.

[0061] According to one embodiment, the MCU obtains the power battery status and matches the output limit strategy according to the power battery status. For example, the power battery status indicates that the battery power is low, and the output limit strategy obtained in this case includes the energy limit coefficient. Energy Limitation Factor It can be set to values ​​such as 0, 0.5, and 1.0, depending on the operating environment and vehicle performance. When the battery is low, a limit coefficient of less than 1 is usually used.

[0062] Step 303: Adjust the output of the power battery according to the output limitation strategy.

[0063] This step is as follows Figure 4 Shown, including:

[0064] Step 401: According to the output limiting strategy, adjust the default given speed to obtain the target given speed.

[0065] In this step, a default given speed corresponding to the current accelerator pedal opening is first obtained. The correlation between the accelerator pedal opening and the default given speed can be preset.

[0066] Then, the default given speed is multiplied by the energy limiting coefficient to obtain the target given speed.

[0067] The speed setting value passes the speed limit, and the given speed Multiply it by the speed limit Kv to get the final given speed .

[0068] Step 402: According to the output limiting strategy, adjust the first corresponding relationship between current and speed to obtain a second corresponding relationship between current and speed.

[0069] The first correspondence includes multiple sets of current-speed correspondences, specifically, motor current / torque current and torque-speed correspondences. Based on this first correspondence, the speed loop limit can be determined. This speed loop limit can be the current loop PI regulation limit, which is used to limit the motor's operating current and, therefore, the battery's output power.

[0070] 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 may be multiplied by the energy limiting coefficient to obtain an adjusted speed value, and the second correspondence may be established between each current value and the adjusted speed value.

[0071] by Figure 2 The speed-current curve shown is an example. Figure 2 The curve A in shows the first correspondence. Figure 5 As 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 correspondence. Figure 2 and Figure 5 In the diagram, the vertical axis represents the current value and the horizontal axis represents the speed value.

[0072] Multiplying the speed value on the horizontal axis of Curve A by the energy limit coefficient yields Curve B. Taking an energy limit coefficient of 0.5 as an example, it can be seen that the speed corresponding to the maximum current point decreases from 800 rpm in Curve A to 400 rpm in Curve B.

[0073] 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.

[0074] Step 403: Adjust the output of the power battery according to the target given speed and the second corresponding relationship.

[0075] In this step, motor control parameters are obtained based on the target given speed, actual speed, and speed loop limiter, and the motor output is controlled to adjust the output of the power battery. The speed loop limiter is obtained based on the second corresponding relationship. Specifically, the current value corresponding to the target given speed can be obtained based on the second corresponding relationship as the speed loop limiter.

[0076] According to one embodiment, after determining that the output of the battery should be adjusted by 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 feedback. , 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.

[0077] According to the default given speed value The actual speed collected by the software , and the current limit value IqMaxMot, the speed loop regulator is calculated and the given torque current is output , input to the current control link to obtain 、 , realizing closed-loop control of motor current.

[0078] An exemplary embodiment of the present disclosure further provides an electric vehicle energy management device, the structure of which is as follows: Figure 6 Shown, including:

[0079] The state detection device 601 is used to detect the driving state of the vehicle;

[0080] A strategy acquisition module 602 is used to acquire a corresponding output restriction strategy according to the driving state;

[0081] The output control module 603 is configured to adjust the output of the power battery according to the output limitation strategy.

[0082] Furthermore, the state detection device 601 is used to detect the vehicle and obtain any one or more of the following driving state information:

[0083] Vehicle driving slope, accelerator pedal opening, and power battery status;

[0084] The strategy acquisition module 602 is configured to obtain an output restriction strategy to be applied from at least one preset output restriction strategy according to the driving state, wherein the output restriction strategy at least includes an energy restriction coefficient.

[0085] Furthermore, the structure of the output control module 603 is as follows: Figure 7 Shown, including:

[0086] The target given speed acquisition submodule 701 is used to adjust the default given speed according to the output limitation strategy to obtain the target given speed;

[0087] a circuit current relationship adjustment submodule 702, configured to adjust the first corresponding relationship between current and speed according to the output limiting strategy to obtain a second corresponding relationship between current and speed;

[0088] The output regulation submodule 703 is configured to regulate the output of the power battery according to the target given speed and the second corresponding relationship.

[0089] Furthermore, the structure of the target given speed acquisition submodule is as follows: Figure 8 Shown, including:

[0090] The default given speed acquisition submodule 801 is used to acquire the default given speed corresponding to the current accelerator pedal opening;

[0091] The target given speed calculation submodule 802 is configured to multiply the default given speed by the energy limiting coefficient to obtain the target given speed.

[0092] Furthermore, the circuit current relationship adjustment submodule 702 is configured 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.

[0093] Furthermore, the output regulation submodule 703 is configured to obtain motor control parameters according to the target given speed, actual speed and speed loop limit value, and control the motor output to regulate the output of the power battery, wherein the speed loop limit value is obtained according to the second corresponding relationship.

[0094] The above device can be integrated into the vehicle's control platform, and the vehicle control platform implements the corresponding functions. Regarding the device in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0095] The disclosed embodiments provide an electric vehicle energy management method and device that detects the vehicle's driving state, then determines a corresponding output limitation strategy based on that state. The output of the power battery is then adjusted based on this output limitation strategy. For operating conditions with special requirements for vehicle performance, the output limitation strategy adjusts the power battery output to achieve smooth vehicle operation, resolving the issue of insufficient battery output power impacting vehicle performance and user experience.

[0096] While reducing the given speed, the speed loop limit value is also adjusted, effectively realizing the control of battery output power.

[0097] Those skilled in the art will also understand that the various illustrative logical blocks and steps listed in the embodiments of this application can be implemented through electronic hardware, computer software, or a combination of both. Whether such functions are implemented through 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 described functions for each specific application, but such implementation should not be construed as exceeding the scope of protection of the embodiments of this application.

[0098] Furthermore, the word "exemplary" is used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as "exemplary" is not necessarily to be construed as advantageous over other aspects or designs. Rather, the use of the word exemplary is intended to present concepts in a concrete manner. As used herein, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or." That is, unless otherwise specified or clear from the context, "X applies to A or B" is intended to mean any of the natural inclusive permutations. That is, if X applies to A; X applies to B; or X applies to both A and B, then "X applies to A or B" satisfies any of the aforementioned instances. Furthermore, the articles "a" and "an," as used in this application and the appended claims, are generally understood to mean "one or more," unless otherwise specified or clear from the context to refer to the singular form.

[0099] 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 upon reading and understanding this specification and the accompanying drawings. The present disclosure includes all such modifications and variations and is limited only by the scope of the claims. With particular regard to the various functions performed by the components described above (e.g., elements, resources, etc.), unless otherwise indicated, terms used to describe such components are intended to correspond to any component (functionally equivalent) that performs the specific function of the described component, even if not structurally equivalent to the disclosed structure. In addition, although particular 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 advantageous for any given or particular application. Furthermore, to the extent that the terms "include," "have," "have," "have," or variations thereof are used in the detailed description or claims, such terms are intended to be inclusive in a manner similar to the term "comprising."

[0100] Other embodiments of the present disclosure will readily occur to those skilled in the art 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 not disclosed herein. The description and examples are to be considered as exemplary only, with the true scope and spirit of the present disclosure being indicated by the following claims.

[0101] 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 can 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: Detecting the driving status of the vehicle; Obtaining a corresponding output restriction strategy according to the driving state; Adjusting the output of the power battery according to the output limiting strategy; The step of obtaining a corresponding output restriction strategy according to the driving state includes: According to the driving state, an output limitation strategy is matched and applied from at least one preset output limitation strategy, wherein the output limitation strategy at least includes an energy limitation coefficient; According to the output limiting strategy, the steps of adjusting the output of the power battery include: 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.

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, 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.

4. The electric vehicle energy management method according to claim 1, 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 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.

5. The electric vehicle energy management method according to claim 1, characterized in that: The step of adjusting the output of the power battery according to the target given speed and the second corresponding relationship includes: Motor control parameters are obtained according to the target given speed, actual speed and speed loop limit value, and 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.

6. 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, configured to acquire a corresponding output restriction strategy according to the driving state; an output control module, configured to adjust the output of the power battery according to the output limitation strategy; 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, configured to adjust the first corresponding relationship between current and speed according to the output limiting strategy to obtain a second corresponding relationship between current and speed; An output regulation submodule is used to regulate the output of the power battery according to the target given speed and the second corresponding relationship.

7. The electric vehicle energy management device according to claim 6, 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, and 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 restriction coefficient.

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