Electric vehicle low-voltage system control method, device, equipment and medium

Abstract

The application provides an electric vehicle low-voltage system control method, device, equipment and medium. In the method, when the voltage conversion device is in a working state, the target output power of the voltage conversion device is determined according to the conversion rate interval corresponding to the obtained low-voltage load rate, and then the voltage conversion device is controlled to output the target output power. According to the present scheme, the target output power of the voltage conversion device is determined through the conversion rate interval corresponding to the low-voltage load rate, so that the energy loss of the voltage conversion device can be reduced, and the energy loss is reduced.

Description

Technical Field

[0001] The present application relates to the field of electric vehicles, and in particular to a method, device, equipment and medium for controlling a low-voltage system of an electric vehicle. Background Art

[0002] With the development of science and technology and people's demand for environmental protection, electric vehicles have emerged. The low-voltage system in an electric vehicle usually consists of a high-voltage power supply, a voltage conversion device, a low-voltage load, and a low-voltage energy storage device.

[0003] In existing technologies, high-voltage power supplies and voltage conversion devices in low-voltage systems typically serve as energy output sources. The high-voltage power output from the high-voltage power supply is converted into low-voltage power by the voltage conversion device and then output to a low-voltage load and a low-voltage energy storage device. The low-voltage load relies on the power output of the voltage conversion device for operation, and the low-voltage energy storage device also relies on the power output of the voltage conversion device for energy storage. When the power requirements of the low-voltage load and the low-voltage energy storage device are low or high, the conversion rate of the voltage conversion device is low.

[0004] In summary, the existing low-voltage system control method uses a voltage conversion device to power the load. When the power demand of the low-voltage load and the low-voltage energy storage device is less or more, the conversion rate of the voltage conversion device is low, which leads to greater energy loss. Summary of the Invention

[0005] The embodiments of the present application provide a method, device, equipment and medium for controlling a low-voltage system of an electric vehicle, which are used to solve the problem that the existing low-voltage system control method uses a voltage conversion device to power the load. When the power required by the low-voltage load and the low-voltage energy storage device is less or more, the conversion rate of the voltage conversion device is low, which leads to large energy loss.

[0006] In a first aspect, an embodiment of the present application provides a method for controlling a low-voltage system of an electric vehicle, comprising:

[0007] If the voltage conversion device of the electric vehicle is in an operating state, obtaining a low-voltage load rate, where the low-voltage load rate is a ratio of the sum of the power requirements of the low-voltage energy storage device and the low-voltage load to the rated power of the voltage conversion device;

[0008] determining a target output power of the voltage conversion device according to a conversion rate interval corresponding to the low voltage load rate, wherein the conversion rate is a conversion ratio between input power and output power of the voltage conversion device;

[0009] The voltage conversion device is controlled to operate according to the target output power.

[0010] In a specific embodiment, determining the target output power of the voltage conversion device according to the conversion rate range corresponding to the low voltage load rate includes:

[0011] If the low voltage load rate belongs to a preset low conversion rate interval, the ratio of the determined target output power to the rated power of the voltage conversion device is less than or equal to a preset first power threshold;

[0012] If the low-voltage load rate does not belong to the preset low conversion rate range, the ratio of the determined target output power to the rated power of the voltage conversion device belongs to the preset high conversion rate range or is greater than the preset second power threshold, the preset second power threshold is greater than the preset first power threshold, the preset high conversion rate range is an interval greater than the preset first threshold and less than the preset second threshold, the preset low conversion rate range is an interval greater than or equal to 0% and less than or equal to the preset first threshold or an interval greater than or equal to the preset second threshold and less than or equal to 100%, and the preset second threshold is greater than the preset first threshold.

[0013] In a specific embodiment, if the low voltage load rate does not belong to the preset low conversion rate range, then the ratio of the target output power to the rated power of the voltage conversion device is determined to belong to a preset high conversion rate range or be greater than a preset second power threshold, including:

[0014] If the low voltage load rate does not belong to the preset low conversion rate range, the determined ratio of the target output power to the rated power of the voltage conversion device belongs to the preset high conversion rate range.

[0015] In a specific embodiment, if the low voltage load rate does not belong to the preset low conversion rate range, then the ratio of the target output power to the rated power of the voltage conversion device is determined to belong to a preset high conversion rate range or be greater than a preset second power threshold, including:

[0016] If the low voltage load rate belongs to the preset high conversion rate range, the determined ratio of the target output power to the rated power of the voltage conversion device belongs to the preset high conversion rate range;

[0017] If the low voltage load rate does not belong to the preset low conversion rate range and does not belong to the preset high conversion rate range, the ratio of the determined target output power to the rated power of the voltage conversion device is greater than or equal to the preset second power threshold.

[0018] In a specific embodiment, if the low voltage load rate belongs to a preset low conversion rate range, after the ratio of the determined target output power to the rated power of the voltage conversion device is less than or equal to a preset first power threshold, the method further includes:

[0019] If the low-voltage energy storage device needs to be charged, the ratio of the target output power to the rated power of the voltage conversion device is controlled to fall within the preset high conversion rate range.

[0020] In a specific embodiment, if the voltage conversion device of the electric vehicle is in an operating state, before obtaining the low-voltage load rate, the method further includes:

[0021] If the voltage conversion device is in an off state and the low-voltage energy storage device needs to be charged, the voltage conversion device is turned on, and the ratio of the target output power to the rated power of the voltage conversion device is controlled to fall within the preset high conversion rate range;

[0022] When the charging of the low-voltage energy storage device is completed, the voltage conversion device is turned off.

[0023] In a second aspect, an embodiment of the present application provides a low-voltage system control device for an electric vehicle, comprising:

[0024] an acquisition module, configured to acquire a low-voltage load rate if the voltage conversion device of the electric vehicle is in an operating state, wherein the low-voltage load rate is a ratio of the sum of the power requirements of the low-voltage energy storage device and the low-voltage load to the rated power of the voltage conversion device;

[0025] a processing module, configured to determine a target output power of the voltage conversion device according to a conversion rate interval corresponding to the low-voltage load rate, wherein the conversion rate is a conversion ratio between an input power and an output power of the voltage conversion device;

[0026] A control module is used to control the voltage conversion device to operate according to the target output power.

[0027] In a third aspect, an embodiment of the present application provides an electronic device, including:

[0028] Processor, memory, communication interface;

[0029] The memory is used to store executable instructions of the processor;

[0030] Wherein, the processor is configured to execute the electric vehicle low-voltage system control method described in any one of the first aspects by executing the executable instructions.

[0031] In a fourth aspect, an embodiment of the present application provides a readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the electric vehicle low-voltage system control method described in any one of the first aspects is implemented.

[0032] In a fifth aspect, an embodiment of the present application provides a computer program product, comprising a computer program, which, when executed by a processor, is used to implement the electric vehicle low-voltage system control method described in any one of the first aspects.

[0033] The electric vehicle low-voltage system control method, device, apparatus, and medium provided in the embodiments of the present application determine the target output power of the voltage conversion device based on the conversion rate range corresponding to the low-voltage load rate when the voltage conversion device is in an operating state, thereby controlling the voltage conversion device to output the target output power. This solution determines the target output power of the voltage conversion device based on the conversion rate range corresponding to the low-voltage load rate, thereby reducing energy loss in the voltage conversion device and lowering energy loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0035] Figure 1 A schematic diagram of the structure of the low-voltage system of the electric vehicle provided in this application;

[0036] Figure 2 A schematic diagram of the corresponding relationship between the low-voltage load rate and the conversion rate provided in this application;

[0037] Figure 3 This is a flow chart of Example 1 of the electric vehicle low-voltage system control method provided in this application;

[0038] Figure 4 This is a flow chart of Example 2 of the electric vehicle low-voltage system control method provided in this application;

[0039] Figure 5 This is a flow chart of Example 3 of the electric vehicle low-voltage system control method provided in this application;

[0040] Figure 6 This is a flow chart of a fourth embodiment of the electric vehicle low-voltage system control method provided in this application;

[0041] Figure 7 A schematic structural diagram of an embodiment of a low-voltage system control device for an electric vehicle provided in this application;

[0042] Figure 8 This is a schematic diagram of the structure of an electronic device provided in this application. DETAILED DESCRIPTION

[0043] To make the purpose, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments made by ordinary technicians in this field based on the inspiration of these embodiments fall within the scope of protection of this application.

[0044] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the numbers used in this way are interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0045] With the development of technology, electric vehicles have emerged. In electric vehicles, low-voltage systems are an indispensable part. For low-voltage systems, they are usually composed of high-voltage power supplies, voltage conversion devices, low-voltage loads, and low-voltage energy storage devices.

[0046] In the prior art, high-voltage power supplies and voltage conversion devices in low-voltage systems typically serve as energy output sources. The high-voltage electricity output by the high-voltage power supply is converted into low-voltage electricity by the voltage conversion device and output to the low-voltage load and low-voltage energy storage device. The low-voltage load relies on the electrical energy output by the voltage conversion device to operate, and the low-voltage energy storage device also relies on the electrical energy output by the voltage conversion device for energy storage. When the power requirements of the low-voltage load and the low-voltage energy storage device are low or high, the conversion rate of the voltage conversion device is low, which in turn leads to large energy losses.

[0047] In response to the problems existing in the prior art, the inventors discovered during their research on the control method for the low-voltage system of an electric vehicle that the output power of the voltage conversion device can be reduced when the power demanded by the low-voltage load and the low-voltage energy storage device is less or more, that is, when the conversion rate of the voltage conversion device is low. Most of the power required by the low-voltage load is provided by the low-voltage energy storage device, and a small part is provided by the voltage conversion device, thereby reducing energy loss. When the low-voltage conversion device is working, if the low-voltage load rate belongs to the preset low conversion rate interval, the target output power is determined so that the ratio of the target output power to the rated power of the voltage conversion device is less than the preset first power threshold, and the low-voltage conversion device is controlled to operate according to the target output power. The low-voltage load rate is the ratio of the sum of the power demanded by the low-voltage energy storage device and the low-voltage load to the rated power of the voltage conversion device. Based on the above-mentioned inventive concept, the control scheme for the low-voltage system of an electric vehicle in this application is designed.

[0048] In the present application, the execution subject of the electric vehicle low-voltage system control method can be the electronic control unit (Electronic Control Unit, abbreviated as: ECU) in the vehicle, or it can be the vehicle controller (VCU), processor and other devices that can control the voltage conversion device in the vehicle. This application does not limit it. The following is an explanation using ECU as an example.

[0049] For example, Figure 1 This is a schematic diagram of the structure of the low-voltage system of the electric vehicle provided in this application, such as Figure 1 As shown, the voltage conversion device 12 is connected to the high-voltage power supply 11, the low-voltage load 13, and the low-voltage energy storage device 14, respectively. It is used to convert the high-voltage power output by the high-voltage power supply 11 into low-voltage power, and output it to the low-voltage load 13 and the low-voltage energy storage device 14. The low-voltage energy storage device 14 is connected to the low-voltage load 13 and can supply power to the low-voltage load 13. The ECU 15 is respectively connected to the voltage conversion device 12, the low-voltage load 13, and the low-voltage energy storage device 14 to obtain the power requirements of the low-voltage load 13 and the low-voltage energy storage device 14, and to control the output power of the voltage conversion device 12.

[0050] When the low-voltage system needs to be controlled, the ECU 15 first determines whether the voltage converter 12 is in operation. If so, to avoid low-conversion-rate conversion by the voltage converter 12, the ECU 15 obtains the corresponding power demand from the low-voltage load 13 and the low-voltage energy storage device 14, and then calculates the low-voltage load rate. The conversion rate is the ratio of the input power to the output power of the voltage converter, while the low-voltage load rate is the ratio of the sum of the power demand of the low-voltage energy storage device and the low-voltage load to the rated power of the voltage converter.

[0051] For example, Figure 2 The corresponding relationship diagram of the low voltage load rate and conversion rate provided in this application is as follows: Figure 2 As shown, if the output power of the voltage conversion device 12 is not controlled, and the required power of the low-voltage load 13 and the low-voltage energy storage device 14 is the output power of the voltage conversion device 12, [0%, 100%] can be divided into three intervals according to the preset first threshold and the preset second threshold. The preset high conversion rate interval is an interval greater than the preset first threshold and less than the preset second threshold, and the preset low conversion rate interval is an interval greater than or equal to 0% and less than or equal to the preset first threshold or an interval greater than or equal to the preset second threshold and less than or equal to 100%, and the preset second threshold is greater than the preset first threshold.

[0052] When the low voltage load rate belongs to the preset high conversion rate range, the conversion rate of the voltage conversion device is high; when the low voltage load rate belongs to the preset low conversion rate range, the conversion rate of the voltage conversion device is low.

[0053] It should be noted that the above example is only an illustration of the correspondence between the low-voltage load rate and the conversion rate, and does not limit the correspondence. The preset first threshold value can be 10%, 15%, or 30%. The preset second threshold value can be 70%, 75, or 80%. The preset low conversion rate interval can be [0%, 10%], [70%, 100%], [0%, 15%], [75%, 100%], or [0%, 30%], [80%, 100%]. The preset high conversion rate interval can be (10%, 70%), (15%, 75%), or (30%, 80%). The embodiment of the present application does not limit the preset first threshold value, the preset second threshold value, the preset low conversion rate interval, and the preset high conversion rate interval, and can be set according to actual conditions.

[0054] When the low-voltage load rate falls within the preset low conversion rate range, the ratio of the determined target output power to the rated power of the voltage conversion device is less than the preset first power threshold. The voltage conversion device 12 is then controlled to operate according to the target output power, so that the power required by the low-voltage load 13 is mostly supplied by the low-voltage energy storage device 14, with a small portion supplied by the voltage conversion device 12, effectively reducing energy loss.

[0055] It should be noted that the preset first power threshold is set by the staff before the implementation of this solution and is used to determine the output power of the voltage conversion device. The preset first power threshold can be 0%, 3%, or even 5%. This embodiment of the application does not limit the preset first power threshold and can be set according to actual circumstances.

[0056] In addition, if the voltage conversion device 12 is not in working condition, the ECU 15 will control the voltage conversion device 12 to start charging the low-voltage energy storage device 14 when it determines that the low-voltage energy storage device 14 needs to be charged, and turn off the voltage conversion device 12 when charging is completed, so as to prevent the low-voltage energy storage device 14 from being damaged due to lack of power.

[0057] It should be noted that the voltage conversion device may be a direct current / direct current (DC / DC) device, a transformer, an alternating current / alternating current (AC / AC) device, a direct current / alternating current (DC / AC) device, or an alternating current / direct current (AC / DC) device. The low-voltage energy storage device may be a battery, capacitor, inductor, or other energy storage device.

[0058] It should be noted that Figure 1 This is only a schematic diagram of a low-voltage system provided in the embodiment of the present application. Figure 1 The actual form of the various devices included in the Figure 1 The interaction mode between devices is limited, and in the specific application of the solution, it can be set according to actual needs.

[0059] The technical solution of the present application is described in detail below through specific embodiments. It should be noted that the following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0060] Figure 3 This is a flow chart of the first embodiment of the low-voltage system control method for electric vehicles provided by this application. This embodiment of the application describes the situation where the voltage conversion device is in a working state, and the target output power of the voltage conversion device is determined according to the conversion rate range corresponding to the low-voltage load rate, and then the voltage conversion device is controlled to operate according to the target output power. The method in this embodiment can be implemented by software, hardware, or a combination of software and hardware. Figure 3 As shown, the electric vehicle low-voltage system control method specifically includes the following steps:

[0061] S301: If the voltage conversion device is in working state, obtain the low voltage load rate.

[0062] When the low-voltage system needs to be controlled, the ECU determines whether the voltage converter is in operation. If the voltage converter is in operation, it indicates that the voltage converter's output power needs to be controlled to reduce energy loss, so the low-voltage load factor is required. The low-voltage load factor is the ratio of the sum of the power requirements of the low-voltage energy storage device and the low-voltage load to the rated power of the voltage converter. Therefore, the ECU can calculate the low-voltage load factor by obtaining the power requirements of the low-voltage energy storage device and the low-voltage load, as well as the rated power of the voltage converter.

[0063] S302: Determine the target output power of the voltage conversion device according to the conversion rate range corresponding to the low voltage load rate.

[0064] In this step, after the ECU obtains the low voltage load rate, in order to determine the output power of the voltage conversion device, it is necessary to determine the target output power of the voltage conversion device according to the conversion rate range corresponding to the low voltage load rate.

[0065] Because the low-voltage load rate corresponds to the conversion rate of the voltage conversion device, [0%, 100%] can be divided into three intervals based on a preset first threshold and a preset second threshold: a low conversion rate interval, a high conversion rate interval, and a low conversion rate interval, respectively. The conversion rate is the conversion ratio of the input power to the output power of the voltage conversion device. If the output power of the voltage conversion device is not controlled, when the low-voltage load rate is in the low conversion rate interval, the conversion rate of the voltage conversion device is low and energy loss is high; when the low-voltage load rate is in the high conversion rate interval, the conversion rate of the voltage conversion device is high and energy loss is low.

[0066] Therefore, if the low-voltage load rate falls within the preset low conversion rate range, it means that if only the voltage conversion device is used to power the low-voltage load, it will result in large energy loss. Therefore, it is necessary to reduce the output power of the voltage conversion device so that the target output power is smaller, and the power required by the load is mainly provided by the low-voltage energy storage device.

[0067] If the low-voltage load rate does not belong to the preset low conversion rate range, it means that the low-voltage load rate belongs to the high conversion rate range or is greater than 100%. At this time, the ratio of the target output power of the voltage conversion device to the rated power of the voltage conversion device should belong to the preset high conversion rate range, or the target output power should be larger to supply power to the low-voltage load.

[0068] S303: Control the voltage conversion device to operate according to the target output power.

[0069] In this step, after determining the target output power, the ECU controls the voltage conversion device to operate according to the target output power, that is, controls the output power of the voltage conversion device to be the target output power.

[0070] It should be noted that the output power of the control voltage conversion device can be changed by keeping the output voltage of the control voltage conversion device unchanged and changing the output current; or by keeping the output current of the control voltage conversion device unchanged and changing the output voltage; or by changing both the output voltage and the output current of the control voltage conversion device at the same time.

[0071] It should be noted that after this solution is executed, it can be executed again after a preset time interval, or it can be executed again immediately. The preset time length can be 3 seconds, 30 seconds, or 3 minutes. The embodiment of this application does not limit the preset time length and can be set according to actual conditions.

[0072] This embodiment provides a method for controlling a low-voltage system in an electric vehicle. When the voltage converter is in operation, the target output power of the voltage converter is determined based on the conversion rate range corresponding to the low-voltage load factor, thereby controlling the voltage converter to operate at the target output power. Compared to existing technologies that do not control the output power of the voltage converter, this solution determines the target output power based on the conversion rate range corresponding to the low-voltage load factor, effectively reducing energy loss.

[0073] Figure 4 This is a flow chart of the second embodiment of the electric vehicle low voltage system control method provided by this application. Based on the above embodiment, this embodiment of the application describes how to determine the target output power of the voltage conversion device according to the conversion rate interval corresponding to the low voltage load rate, and control the voltage conversion device to operate according to the target output power. Figure 4 As shown, the electric vehicle low-voltage system control method specifically includes the following steps:

[0074] S401: Obtain low voltage load rate.

[0075] In this step, when the ECU determines that the voltage conversion device is in the working state, in order to determine the target output power of the low-voltage conversion device, it is necessary to obtain the low-voltage load rate.

[0076] S402: Determine whether the low voltage load rate belongs to a preset low conversion rate range; if the low voltage load rate belongs to the preset low conversion rate range, execute S403; if the low voltage load rate does not belong to the preset low conversion rate range, execute S405.

[0077] S403: The ratio of the determined target output power to the rated power of the voltage conversion device is less than or equal to a preset first power threshold.

[0078] S404: Determine whether the low-voltage energy storage device needs to be charged; if the low-voltage energy storage device needs to be charged, execute S405; if the low-voltage energy storage device does not need to be charged, execute S406.

[0079] S405: The ratio of the determined target output power to the rated power of the voltage conversion device belongs to a preset high conversion rate range.

[0080] S406: Control the voltage conversion device to operate according to the target output power.

[0081] In the above steps, after the ECU obtains the low-voltage load rate, it determines whether the low-voltage load rate belongs to a preset low conversion rate range.

[0082] If the low-voltage load rate falls within the preset low conversion rate range, it means that if only the voltage conversion device is used to power the low-voltage load, it will result in large energy loss. Therefore, it is necessary to reduce the output power of the voltage conversion device and determine the target output power so that the ratio of the target output power to the rated power of the voltage conversion device is less than or equal to the preset low-power threshold.

[0083] If the low-voltage load rate does not fall within the preset low conversion rate range, but rather falls within the high conversion rate range or is greater than 100%, the target output power is determined such that the ratio of the target output power to the rated power of the voltage conversion device falls within the preset high conversion rate range. This allows the low-voltage load to be powered by both the voltage conversion device and the low-voltage energy storage device, or the voltage conversion device to have a higher conversion rate, reducing energy loss.

[0084] After determining the target output power so that the ratio of the target output power to the rated power of the voltage conversion device is less than or equal to the preset first power threshold, in order to ensure that the low-voltage energy storage device has sufficient power, it is also necessary to determine whether the low-voltage energy storage device needs to be charged.

[0085] It should be noted that the method for determining whether the low-voltage energy storage device needs to be charged can be to determine whether the voltage of the low-voltage energy storage device is less than the preset protection voltage, to determine whether the discharge time of the low-voltage energy storage device is greater than the preset protection time, or to determine whether the state of charge (SOC) of the low-voltage energy storage device is less than the preset protection SOC threshold. The preset protection voltage can be 10V, 15V, or 20V. The preset protection time can be 10 days, 20 days, or 30 days. The preset protection SOC threshold can be 5%, 10%, or 15%. The embodiment of the present application does not limit the method for determining whether the low-voltage energy storage device needs to be charged, as well as the preset protection voltage, preset protection time, and preset protection SOC threshold, and can be set according to actual conditions.

[0086] If the low-voltage energy storage device needs to be charged, the target output power is determined so that the ratio of the target output power to the rated power of the voltage conversion device falls within a preset high conversion rate range. This allows for rapid battery charging. The voltage conversion device is then controlled to operate at the target output power.

[0087] If the low-voltage energy storage device does not need to be charged, the voltage conversion device is controlled to operate according to the target output power, and the ratio of the target output power to the rated power of the voltage conversion device is less than or equal to a preset first power threshold.

[0088] The electric vehicle low-voltage system control method provided in this embodiment controls the output power of the voltage conversion device to decrease when the low-voltage load rate falls within a preset low conversion rate range and the low-voltage energy storage device does not need to be charged, so that the low-voltage load is primarily powered by the low-voltage energy storage device, effectively reducing energy loss. When the low-voltage load rate does not fall within the low conversion rate range, or when the low-voltage load rate falls within a preset low-efficiency range and the low-voltage energy storage device needs to be charged, the voltage conversion device is controlled to output at a high conversion rate, ensuring the normal operation of the low-voltage load and preventing the low-voltage energy storage device from running out of power.

[0089] Figure 5 This is a flow chart of the third embodiment of the low-voltage system control method for electric vehicles provided by this application. Based on the above embodiments, this embodiment of the application describes the situation where the target output power is determined based on whether the low-voltage load rate belongs to the preset high conversion rate range when the low-voltage load rate does not belong to the preset low conversion rate range. Figure 5 As shown, the electric vehicle low-voltage system control method specifically includes the following steps:

[0090] S501: Determine whether the low voltage load rate does not belong to a preset low conversion rate range.

[0091] In this step, the ECU obtains the low-voltage load rate and determines whether the low-voltage load rate belongs to the preset low conversion rate range. If it is determined that the low-voltage load rate does not belong to the preset low conversion rate range, it means that the low-voltage load rate belongs to the preset high conversion rate range, or is greater than 100%, and further determination is required.

[0092] S502: Determine whether the low voltage load rate belongs to the preset high conversion rate range; if the low voltage load rate belongs to the preset high conversion rate range, execute S503; if the low voltage load rate does not belong to the preset high conversion rate range, execute S504.

[0093] S503: The ratio of the determined target output power to the rated power of the voltage conversion device belongs to a preset high conversion rate range.

[0094] S504: The ratio of the determined target output power to the rated power of the voltage conversion device is greater than or equal to a preset second power threshold.

[0095] In the above steps, after the ECU determines that the low-voltage load rate does not belong to the preset low conversion rate range, it determines whether the low-voltage load rate belongs to the preset high conversion rate range.

[0096] If the low-voltage load rate falls within the preset high conversion rate range, it means that the high conversion rate output of the voltage conversion device can not only meet the needs of the low-voltage load, but also reduce energy loss. Therefore, the target output power is determined so that the ratio of the target output power to the rated power of the voltage conversion device falls within the preset high conversion rate range.

[0097] If the low-voltage load rate does not fall within the preset high conversion rate range, indicating that the low-voltage load rate exceeds 100%, the low-voltage load's power demand is very high. The target output power is determined so that the ratio of the target output power to the rated power of the voltage conversion device is greater than or equal to a preset second power threshold. The voltage conversion device is controlled to output high power, while the low-voltage energy storage device also supplies power to the low-voltage load to meet the low-voltage load's demand. The preset second power threshold is greater than the preset first power threshold.

[0098] It should be noted that the preset second power threshold is set by the staff before the implementation of this solution and is used to determine the output power of the voltage conversion device. The preset second power threshold can be 90%, 95%, or even 100%. This embodiment of the application does not limit the preset second power threshold and can be set according to actual circumstances.

[0099] The electric vehicle low-voltage system control method provided in this embodiment determines a target output power when the low-voltage load rate falls within the high conversion rate range, such that the ratio of the target output power to the rated power of the voltage conversion device falls within the preset high conversion rate range, effectively ensuring normal load operation and reducing energy loss. When the low-voltage load rate exceeds 100%, the target output power is determined such that the ratio of the target output power to the rated power of the voltage conversion device is greater than or equal to a preset high-power threshold, ensuring normal operation of the low-voltage load.

[0100] Figure 6 This is a flow chart of the fourth embodiment of the low-voltage system control method for electric vehicles provided by this application. Based on the above embodiments, this embodiment of the application describes the situation where the voltage conversion device is not in a working state and the voltage conversion device is turned on when the low-voltage energy storage device needs to be charged to ensure that the low-voltage energy storage device is not depleted. Figure 6 As shown, the electric vehicle low-voltage system control method specifically includes the following steps:

[0101] S601: Determine whether the voltage conversion device is in an off state.

[0102] In this step, when the low-voltage system needs to be controlled, the ECU will determine whether the voltage conversion device is in working condition. If the voltage conversion device is in the off state, it means that the low-voltage energy storage device is not supplying power to the low-voltage load at this time, and it is necessary to prevent the low-voltage energy storage device from running out of power.

[0103] S602: Determine whether the low-voltage energy storage device needs to be charged. If the low-voltage energy storage device needs to be charged, execute S603; if the low-voltage energy storage device does not need to be charged, execute S605.

[0104] S603: Turn on the voltage conversion device, and control the ratio of the target output power to the rated power of the voltage conversion device to fall within a preset high conversion rate range.

[0105] S604: When the low-voltage energy storage device finishes charging, the voltage conversion device is turned off.

[0106] S605: End the execution of this plan.

[0107] In the above steps, after the ECU determines that the voltage converter is off, it then determines whether the low-voltage energy storage device needs to be charged. If the low-voltage energy storage device needs to be charged, the voltage converter is turned on and a target output power is determined such that the ratio of the target output power to the rated power of the voltage converter falls within a preset high conversion rate range. The voltage converter is then controlled to operate at the target output power. When the low-voltage energy storage device is fully charged, the voltage converter is turned off.

[0108] It should be noted that the method for determining the end of charging can be that the state of charge (SOC) of the low-voltage energy storage device is greater than a preset full-charge SOC threshold, or that the voltage of the low-voltage energy storage device is greater than a preset full-charge voltage. The preset full-charge SOC threshold can be 90%, 95%, or 99%. The preset full-charge voltage can be 11V, 15V, or 23V. The embodiments of this application do not limit the method for determining the end of charging, the preset full-charge SOC threshold, and the preset full-charge voltage, and they can be set according to actual circumstances.

[0109] If the low-voltage energy storage device does not need to be charged, the execution of this plan is terminated and the low-voltage energy storage device continues to supply power to the low-voltage load.

[0110] The electric vehicle low-voltage system control method provided in this embodiment prevents the low-voltage energy storage device from running out of power by turning on the voltage conversion device to power the low-voltage energy storage device when the voltage conversion device is in the off state and needs to be charged. Furthermore, the voltage conversion device operates at a high conversion rate, effectively reducing energy loss.

[0111] The following are device embodiments of the present application, which can be used to implement the method embodiments of the present application. For details not disclosed in the device embodiments of the present application, please refer to the method embodiments of the present application.

[0112] Figure 7 This is a structural diagram of an embodiment of the electric vehicle low-voltage system control device provided in this application.

[0113] like Figure 7As shown, the electric vehicle low voltage system control device 70 includes:

[0114] an acquisition module 71 for acquiring a low-voltage load rate if the voltage conversion device of the electric vehicle is in an operating state, wherein the low-voltage load rate is a ratio of the sum of the power requirements of the low-voltage energy storage device and the low-voltage load to the rated power of the voltage conversion device;

[0115] a processing module 72 for determining a target output power of the voltage conversion device according to a conversion rate interval corresponding to the low voltage load rate, wherein the conversion rate is a conversion ratio between an input power and an output power of the voltage conversion device;

[0116] The control module 73 is used to control the voltage conversion device to operate according to the target output power.

[0117] Furthermore, the processing module 72 is specifically configured to:

[0118] If the low voltage load rate belongs to a preset low conversion rate interval, the ratio of the determined target output power to the rated power of the voltage conversion device is less than or equal to a preset first power threshold;

[0119] If the low-voltage load rate does not belong to the preset low conversion rate range, the ratio of the determined target output power to the rated power of the voltage conversion device belongs to the preset high conversion rate range or is greater than the preset second power threshold, the preset second power threshold is greater than the preset first power threshold, the preset high conversion rate range is an interval greater than the preset first threshold and less than the preset second threshold, the preset low conversion rate range is an interval greater than or equal to 0% and less than or equal to the preset first threshold or an interval greater than or equal to the preset second threshold and less than or equal to 100%, and the preset second threshold is greater than the preset first threshold.

[0120] Furthermore, the processing module 72 is further configured to:

[0121] If the low voltage load rate does not belong to the preset low conversion rate range, the determined ratio of the target output power to the rated power of the voltage conversion device belongs to the preset high conversion rate range.

[0122] Furthermore, the processing module 72 is further configured to:

[0123] If the low voltage load rate belongs to the preset high conversion rate range, the determined ratio of the target output power to the rated power of the voltage conversion device belongs to the preset high conversion rate range;

[0124] If the low voltage load rate does not belong to the preset low conversion rate range and does not belong to the preset high conversion rate range, the ratio of the determined target output power to the rated power of the voltage conversion device is greater than or equal to the preset second power threshold.

[0125] Furthermore, the control module 72 is further configured to:

[0126] If the low-voltage energy storage device needs to be charged, the ratio of the target output power to the rated power of the voltage conversion device is controlled to fall within the preset high conversion rate range.

[0127] Furthermore, the control module 72 is further configured to:

[0128] If the voltage conversion device is in an off state and the low-voltage energy storage device needs to be charged, the voltage conversion device is turned on, and the ratio of the target output power to the rated power of the voltage conversion device is controlled to fall within the preset high conversion rate range;

[0129] When the charging of the low-voltage energy storage device is completed, the voltage conversion device is turned off.

[0130] The electric vehicle low-voltage system control device provided in this embodiment is used to implement the technical solution in any of the aforementioned method embodiments. Its implementation principles and technical effects are similar and will not be repeated here.

[0131] Figure 8 This is a schematic diagram of the structure of an electronic device provided by this application. Figure 8 As shown, the electronic device 80 includes:

[0132] Processor 81, memory 82, and communication interface 83;

[0133] The memory 82 is used to store executable instructions of the processor 81;

[0134] The processor 81 is configured to execute the technical solution in any of the aforementioned method embodiments by executing the executable instructions.

[0135] Optionally, the memory 82 can be independent or integrated with the processor 81.

[0136] Optionally, when the memory 82 is a device independent of the processor 81, the electronic device 80 may further include:

[0137] The bus 84 , the memory 82 and the communication interface 83 are connected to the processor 81 via the bus 84 and communicate with each other. The communication interface 83 is used to communicate with other devices.

[0138] Optionally, the communication interface 83 may be implemented using a transceiver. The communication interface is used to enable communication between the database access device and other devices (e.g., a client, a read-write library, and a read-only library). The memory may include random access memory (RAM) and may also include non-volatile memory (non-volatile memory), such as at least one disk storage device.

[0139] Bus 84 may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. Buses can be categorized as address buses, data buses, and control buses. For ease of illustration, the figure uses only one thick line, but this does not imply that there is only one bus or only one type of bus.

[0140] The above-mentioned processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, and discrete hardware components.

[0141] The electronic device is used to execute the technical solution in any of the aforementioned method embodiments, and its implementation principles and technical effects are similar and will not be repeated here.

[0142] An embodiment of the present application further provides a readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the technical solution provided by any of the aforementioned method embodiments.

[0143] An embodiment of the present application also provides a computer program product, including a computer program, which, when executed by a processor, is used to implement the technical solution provided by any of the aforementioned method embodiments.

[0144] Those skilled in the art will appreciate that all or part of the steps in the above-described method embodiments can be implemented using hardware associated with program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0145] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for controlling a low-voltage system of an electric vehicle, characterized in that: include: If the voltage conversion device of the electric vehicle is in an operating state, obtaining a low-voltage load rate, where the low-voltage load rate is a ratio of the sum of the power requirements of the low-voltage energy storage device and the low-voltage load to the rated power of the voltage conversion device; determining a target output power of the voltage conversion device according to a conversion rate interval corresponding to the low voltage load rate, wherein the conversion rate is a conversion ratio between input power and output power of the voltage conversion device; controlling the voltage conversion device to operate according to the target output power; The determining the target output power of the voltage conversion device according to the conversion rate interval corresponding to the low voltage load rate includes: If the low-voltage load rate does not belong to the preset low conversion rate range, the ratio of the determined target output power to the rated power of the voltage conversion device belongs to the preset high conversion rate range or is greater than the preset second power threshold. The preset high conversion rate range is an interval greater than the preset first threshold and less than the preset second threshold. The preset low conversion rate range is an interval greater than or equal to 0% and less than or equal to the preset first threshold or an interval greater than or equal to the preset second threshold and less than or equal to 100%. The preset second threshold is greater than the preset first threshold.

2. The method according to claim 1, characterized in that The determining the target output power of the voltage conversion device according to the conversion rate interval corresponding to the low voltage load rate further includes: If the low voltage load rate belongs to the preset low conversion rate range, the ratio of the determined target output power to the rated power of the voltage conversion device is less than or equal to the preset first power threshold, and the preset second power threshold is greater than the preset first power threshold.

3. The method according to claim 2, characterized in that If the low voltage load rate does not belong to the preset low conversion rate range, the ratio of the target output power to the rated power of the voltage conversion device is determined to belong to a preset high conversion rate range or be greater than a preset second power threshold, including: If the low voltage load rate does not belong to the preset low conversion rate range, the determined ratio of the target output power to the rated power of the voltage conversion device belongs to the preset high conversion rate range.

4. The method according to claim 2, characterized in that If the low voltage load rate does not belong to the preset low conversion rate range, the ratio of the target output power to the rated power of the voltage conversion device is determined to belong to a preset high conversion rate range or be greater than a preset second power threshold, including: If the low voltage load rate belongs to the preset high conversion rate range, the determined ratio of the target output power to the rated power of the voltage conversion device belongs to the preset high conversion rate range; If the low voltage load rate does not belong to the preset low conversion rate range and does not belong to the preset high conversion rate range, the ratio of the determined target output power to the rated power of the voltage conversion device is greater than or equal to the preset second power threshold.

5. The method according to any one of claims 2 to 4, characterized in that If the low voltage load rate belongs to the preset low conversion rate range, after the ratio of the determined target output power to the rated power of the voltage conversion device is less than or equal to a preset first power threshold, the method further includes: If the low-voltage energy storage device needs to be charged, the ratio of the target output power to the rated power of the voltage conversion device is controlled to fall within the preset high conversion rate range.

6. The method according to claim 5, characterized in that If the voltage conversion device of the electric vehicle is in an operating state, before obtaining the low-voltage load rate, the method further includes: If the voltage conversion device is in an off state and the low-voltage energy storage device needs to be charged, the voltage conversion device is turned on, and the ratio of the target output power to the rated power of the voltage conversion device is controlled to fall within the preset high conversion rate range; When the charging of the low-voltage energy storage device is completed, the voltage conversion device is turned off.

7. A low-voltage system control device for an electric vehicle, characterized in that: include: an acquisition module, configured to acquire a low-voltage load rate if the voltage conversion device of the electric vehicle is in an operating state, wherein the low-voltage load rate is a ratio of the sum of the power requirements of the low-voltage energy storage device and the low-voltage load to the rated power of the voltage conversion device; a processing module, configured to determine a target output power of the voltage conversion device according to a conversion rate interval corresponding to the low-voltage load rate, wherein the conversion rate is a conversion ratio between an input power and an output power of the voltage conversion device; a control module, configured to control the voltage conversion device to operate according to the target output power; The processing module is specifically used to determine, if the low-voltage load rate does not belong to the preset low conversion rate range, that the ratio of the determined target output power to the rated power of the voltage conversion device belongs to the preset high conversion rate range or is greater than the preset second power threshold. The preset high conversion rate range is an interval greater than the preset first threshold and less than the preset second threshold, and the preset low conversion rate range is an interval greater than or equal to 0% and less than or equal to the preset first threshold or an interval greater than or equal to the preset second threshold and less than or equal to 100%, and the preset second threshold is greater than the preset first threshold.

8. An electronic device, characterized in that: include: Processor, memory, communication interface; The memory is used to store executable instructions of the processor; The processor is configured to execute the electric vehicle low-voltage system control method according to any one of claims 1 to 6 by executing the executable instructions.

9. A readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the electric vehicle low-voltage system control method according to any one of claims 1 to 6 is implemented.

10. A computer program product, characterized in that The invention comprises a computer program, which is used to implement the electric vehicle low-voltage system control method according to any one of claims 1 to 6 when executed by a processor.

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