Power generation control method and system for low-temperature cold start engine of extended-range hybrid vehicle

Abstract

The invention discloses a power generation control method and system for a low-temperature cold start engine of an extended-range hybrid vehicle. The power generation control method comprises the steps of judging the low battery capacity at the low temperature and starting the engine at the low temperature. Whether the engine needs to be started or not is quickly judged by judging the battery core temperature and the battery discharging power, compared with a traditional method that after the SOC electric quantity is low, the engine starting speed is higher, safety and reliability are achieved, then the engine is controlled to be quickly started to the target rotating speed in a torque mode, the whole vehicle noise is reduced, and the engine enters a series power generation mode. According to the whole control method, the reliability, safety and comfort of the low-temperature cold start engine power generation control method of the whole hybrid extended-range automobile are improved.

Description

TECHNICAL FIELD

[0001] The embodiment of the application relates to the technical field of extended-range hybrid vehicles, and particularly relates to a power generation control method and system for a low-temperature cold-start engine of an extended-range hybrid vehicle. BACKGROUND

[0002] In the current situation of global energy supply tension and increasingly prominent ecological environment problems, the exploration and popularization of extended-range hybrid vehicles have become the only way to promote the progress of the times. With the increasing complexity of vehicle system architecture, the core position of vehicle control is increasingly prominent. It is like the heart and brain of new energy vehicles and is one of the key bottlenecks of technological innovation and development. Under this background, the strategy design of the extended-range hybrid vehicle starting engine power generation is not only necessary to build a solid vehicle control cornerstone, but also a key link to improve the overall reliability of the vehicle. The current low-temperature cold-start engine power generation control method cannot meet the user's low-temperature cold-start requirements. SUMMARY

[0003] Therefore, the embodiment of the application provides a power generation control method and system for a low-temperature cold-start engine of an extended-range hybrid vehicle, which can quickly judge the battery power at low temperature, control the engine start to drive the engine to generate power and reduce the damage possibility of high-voltage components, thereby improving the reliability and safety of the vehicle high-voltage system.

[0004] In order to achieve the above-mentioned purpose, the embodiment of the application provides the following technical scheme: According to the first aspect of the embodiment of the application, the embodiment of the application provides a power generation control method for a low-temperature cold-start engine of an extended-range hybrid vehicle. The method is executed by a power system controller HCU, and the method comprises the following steps: The power system controller is woken up and self-checking is completed. The discharge power and the cell temperature of the battery are obtained, and it is judged whether the battery power is in an excessively low state according to the discharge power and the cell temperature of the battery. If the battery power is excessively low, the high voltage on the vehicle is requested, and the low-temperature cold-start engine starts to generate power after the vehicle enters the high-voltage state.

[0005] Further, the power system controller is woken up and self-checking is completed, specifically comprising the following steps: The power system controller is woken up and self-checking is started. If the self-checking fails, the controller is restarted.

[0006] Further, the power system controller is woken up and self-checking is completed, specifically comprising the following steps: The power system controller waking up comprises hard-wire waking up and CAN line waking up.

[0007] Further, the discharge power of the battery and the cell temperature are acquired, and whether the battery power is in an excessively low state is determined according to the discharge power of the battery and the cell temperature, and specifically includes: The threshold values of the cell temperature and the battery discharge power are set, whether the cell temperature is lower than the set threshold value is checked, and whether the battery discharge power is lower than the set threshold value is checked, and if both conditions are met, the process of low-temperature cold starting the engine is triggered.

[0008] Further, the discharge power of the battery and the cell temperature are acquired, and whether the battery power is in an excessively low state is determined according to the discharge power of the battery and the cell temperature, and specifically includes: The temperature of each cell of the battery is monitored in real time through the BMS system, and the real-time discharge power data of the battery is acquired through the BMS.

[0009] Further, if the battery power is excessively low, the high voltage of the whole vehicle is requested, and after the whole vehicle is controlled to enter the high voltage state, the low-temperature cold starting engine starts to generate electricity, and specifically includes: The BMS high voltage is requested to be powered on, if the high voltage requirement is met, the BMS controls the relay to be closed, and after the HCU receives the successful feedback of the relay closure of the BMS, the whole vehicle is controlled to enter the high voltage state.

[0010] Further, if the battery power is excessively low, the high voltage of the whole vehicle is requested, and after the whole vehicle is controlled to enter the high voltage state, the low-temperature cold starting engine starts to generate electricity, and specifically includes: After the BMS high voltage of the whole vehicle is requested, the BMS is pre-charged, after the pre-charging is successful, the main positive relay is closed, otherwise a high voltage power-on timeout fault is reported.

[0011] Further, if the battery power is excessively low, the high voltage of the whole vehicle is requested, and after the whole vehicle is controlled to enter the high voltage state, the low-temperature cold starting engine starts to generate electricity, and specifically includes: After the whole vehicle is controlled to enter the high voltage state, the engine is requested to start, the engine enters the torque control mode, quickly drives the engine to the target speed, and then enters the speed mode, the engine is in the process of stopping mode, enters the starting mode, and then enters the running mode, and the engine outputs positive torque to enter the series power generation mode.

[0012] Further, the method further includes: The BMS is used to monitor the battery state to prevent overcharging or overdischarging, and the HCU continuously monitors the safety parameters in the whole process to ensure the stable operation of the system.

[0013] According to the second aspect of the embodiment of the application, the embodiment of the application provides a power generation control system for low-temperature cold starting an engine of a range-extended hybrid vehicle, and the system includes: The wake-up module is used for the power system controller to wake up and complete self-checking. The battery power judgment module at low temperature is used for acquiring the discharge power and the cell temperature of the battery, and judging whether the battery power is in an excessively low state according to the discharge power and the cell temperature of the battery. The engine starting module at low temperature is used for requesting high voltage on the whole vehicle if the battery power is excessively low, and starting the engine to generate electricity after the whole vehicle enters the high voltage state.

[0014] Compared with the prior art, the power generation control method and system for the engine of the extended-range hybrid vehicle at low temperature provided by the application include the battery power judgment module at low temperature and the engine starting module at low temperature, which can quickly judge whether the engine needs to be started according to the cell temperature and the battery discharge power, and the speed of starting the engine is faster than that of the conventional method of starting the engine after judging that the SOC power is low, and the safety and reliability are higher, then the engine is started to the target speed in the torque mode to reduce the noise of the whole vehicle, and the engine enters the series power generation mode. The whole control method improves the reliability, safety and comfort of the power generation control method for the engine of the extended-range hybrid vehicle at low temperature. BRIEF DESCRIPTION OF DRAWINGS

[0015] The drawings constituting a part of the specification of the application are used to provide further understanding of the application, the illustrative embodiments of the application and the description thereof are used to explain the application, and do not constitute improper limitation on the application. In the drawings: Figure 1 The flowchart of the power generation control method for the engine of the extended-range hybrid vehicle at low temperature provided by the embodiment of the application is shown in the figure. Figure 2 The specific implementation flowchart of the power generation control method for the engine of the extended-range hybrid vehicle at low temperature provided by the embodiment of the application is shown in the figure. Figure 3 The structure schematic diagram of the power generation control system for the engine of the extended-range hybrid vehicle at low temperature provided by the embodiment of the application is shown in the figure. DETAILED DESCRIPTION

[0016] The application will be described in detail below with reference to the drawings and in combination with the embodiments. It should be noted that the embodiments in the application and the features in the embodiments can be combined with each other without conflict.

[0017] The following detailed description is exemplary description, which aims to provide further detailed description of the application. Unless otherwise specified, all technical terms used in the application have the same meaning as that understood by the general technical personnel in the field to which the application belongs. The terms used in the application are only used to describe the specific embodiments, and are not intended to limit the exemplary embodiments according to the application.

[0018] The first embodiment of the present invention provides a method for controlling engine power generation during cold-starts in a range-extended hybrid vehicle. This method quickly determines low battery charge at low temperatures, controls engine start-up to drive engine power generation, and reduces the risk of damage to high-voltage components, thereby improving the reliability and safety of the vehicle's high-voltage system. The method primarily includes processes for determining low battery charge at low temperatures and starting the engine at low temperatures.

[0019] Determining the battery charge at low temperatures involves the following steps: The power system controller is woken up. The HCU determines whether the battery power is too low by the battery discharge power and cell temperature. If the battery power is too low, the HCU requests the BMS to power on the high voltage. If the high voltage requirement is met, the BMS control relay is closed. The HCU receives feedback from the BMS that the relay is closed successfully; then the HCU controls the entire vehicle to enter the high voltage state.

[0020] The low temperature engine start procedure includes the following steps: After the HCU controls the entire vehicle to enter a high-voltage state, it requests the engine to start. The engine enters the torque control mode, quickly drives the engine to the target speed, and then enters the speed mode. During this process, the engine enters the start mode from the stop mode, and then enters the run mode, outputting positive torque to start generating electricity.

[0021] The following combination Figure 1 A first embodiment of the present invention provides a method for controlling power generation of an engine of an extended-range hybrid vehicle during a cold start.

[0022] like Figure 1 As shown, in step S100 , the power system controller wakes up and completes self-test.

[0023] The above steps specifically include: S110: The powertrain controller wakes up and starts self-testing. If the self-test fails, the controller is restarted. Controller wakeup includes hardwire wakeup and CAN line wakeup.

[0024] like Figure 2 As shown, in step S200, the discharge power and cell temperature of the battery are obtained, and it is determined whether the battery power is in a too low state according to the discharge power and cell temperature of the battery.

[0025] The above steps specifically include: S210: Monitor the temperature of each battery cell in real time through the BMS system, and obtain real-time discharge power data of the battery through the BMS.

[0026] S220, setting thresholds for the cell temperature and the battery discharge power, checking whether the cell temperature is lower than the set thresholds and checking whether the battery discharge power is lower than the set thresholds. If both conditions are met, triggering the low-temperature cold start process for the engine.

[0027] After the controller wakes up, it is determined whether to start the engine to generate electricity at low temperature according to the battery cell temperature and the battery discharge power, and if the conditions are met, the high voltage of the whole vehicle is requested.

[0028] As shown in Figure 1 , if the battery power is too low in step S300, the high voltage of the whole vehicle is requested, and after the whole vehicle enters the high voltage state, the engine starts to generate electricity at low temperature.

[0029] The above steps specifically include: S310, request BMS high voltage power-on, if the high voltage requirement is met, the BMS controls the relay to close, and the HCU controls the whole vehicle to enter the high voltage state after receiving the successful feedback of the relay closing of the BMS.

[0030] In this embodiment, after requesting the BMS to turn on the high voltage of the whole vehicle, the BMS pre-charges, closes the main positive relay after pre-charging is successful, or reports a high voltage power-on timeout fault.

[0031] S320, after controlling the whole vehicle to enter the high voltage state, the engine is started, the engine enters the torque control mode, quickly drives the engine to the target speed, and then enters the speed mode, the engine enters the start mode from the stop mode, and then enters the running mode, the engine outputs positive torque to enter the series generation mode. The whole starting process fully considers the whole vehicle NVH, and controls the whole vehicle starting noise within a reasonable range.

[0032] In this embodiment, the method further includes: S400, the battery state is monitored by the BMS to prevent overcharging or overdischarging; the HCU continuously monitors the safety parameters in the whole process to ensure stable operation of the system.

[0033] The whole process is summarized as follows: the power system controller wakes up and starts self-checking, and if the self-checking fails, the controller is restarted. The controller wake-up includes hard-wire wake-up and CAN line wake-up. After the controller wakes up, it is determined whether to start the engine to generate electricity at low temperature according to the battery cell temperature and the battery discharge power, and if the conditions are met, the high voltage of the whole vehicle is requested, the BMS pre-charges, the main positive relay is closed after pre-charging is successful, or a high voltage power-on timeout fault is reported. After the whole vehicle enters the high voltage state, the engine starts and enters the torque mode, drives the engine to start, and the engine drives the speed to the target speed and then enters the speed mode, and the engine outputs positive torque to enter the series generation mode.

[0034] Corresponding to the above-mentioned embodiment, the present embodiment also discloses a kind of power generation control method of engine cold start at low temperature of range-extended hybrid vehicle, as shown in Figure 3 , it specifically includes: a wake-up module configured to wake up the power system controller and complete a self-check; a low-temperature battery power determination module configured to obtain a discharge power of the battery and a temperature of a battery cell, and determine whether the battery power is in an excessively low state according to the discharge power of the battery and the temperature of the battery cell; a low-temperature engine starting module configured to request high voltage on the vehicle if the battery power is excessively low, and start the engine to generate power after the vehicle enters a high-voltage state.

[0035] It should be noted that the detailed description of the power generation control system for the low-temperature cold start engine of the range-extending hybrid vehicle provided by the embodiment of the present application can refer to the related description of the power generation control method for the low-temperature cold start engine of the range-extending hybrid vehicle provided by the embodiment of the present application, which will not be repeated here.

[0036] From the common general knowledge, the present application can be realized by other embodiments without departing from the spirit or essential characteristics of the present application. Therefore, the above-mentioned disclosed embodiments are only examples, and are not the only ones. All changes within the scope of the present application or within the scope equivalent to the present application are included in the present application.

[0037] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0038] The present application is described with reference to flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams can be realized by computer program instructions. These computer program instructions can be provided to a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to produce a machine, so that the instructions executed by the computer or other programmable data processing devices produce a device that implements the functions specified in the flowcharts and / or block diagrams. Figure 1 a device that implements the functions specified in one or more flows and / or blocks. Figure 1 a device that implements the functions specified in one or more flows and / or blocks.

[0039] These computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture including instructions which implement the flow Figure 1 The functions of a flow or multiple flows and / or a block or multiple blocks in conjunction with the disclosed methods. Figure 1

[0040] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flow Figure 1 The functions of a flow or multiple flows and / or a block or multiple blocks in conjunction with the disclosed methods. Figure 1 The functions of a flow or multiple flows and / or a block or multiple blocks in conjunction with the disclosed methods.

[0041] Finally, it should be noted that the above-mentioned embodiments are merely used to illustrate the technical solutions of the present application, rather than limiting the same. Although the present application has been described in detail with reference to the above-mentioned embodiments, those skilled in the art should understand that the specific embodiments of the present application can be modified or replaced equivalently, and any modification or replacement without departing from the spirit and scope of the present application should be covered within the protection scope of the claims of the present application.​

Claims

1. A method for controlling power generation of a low-temperature cold-start engine of a range-extended hybrid vehicle, characterized in that: Executed by a powertrain controller HCU, the method includes: The powertrain controller wakes up and completes self-test; Obtain the battery's discharge power and cell temperature, and determine whether the battery power is too low based on the battery's discharge power and cell temperature; If the battery power is too low, the vehicle is requested to be on high voltage, and after the vehicle is controlled to enter the high voltage state, the engine is cold-started at low temperature to start generating electricity.

2. The method for controlling power generation of a low-temperature cold-start engine of a range-extended hybrid vehicle according to claim 1, characterized in that: The powertrain controller wakes up and completes a self-test, including: The powertrain controller wakes up and starts a self-test. If the self-test fails, the controller is restarted.

3. The method for controlling power generation of a low-temperature cold-start engine of a range-extended hybrid vehicle according to claim 2, characterized in that: The powertrain controller wakes up and completes a self-test, including: Powertrain controller wakeup includes hardwire wakeup and CAN line wakeup.

4. The method for controlling power generation of a low-temperature cold-start engine of a range-extended hybrid vehicle according to claim 1, characterized in that: Obtain the battery's discharge power and cell temperature, and determine whether the battery power is too low based on the battery's discharge power and cell temperature. This includes: Set the thresholds for the battery cell temperature and battery discharge power, check whether the battery cell temperature is lower than the set thresholds and check whether the battery discharge power is lower than the set thresholds. If both conditions are met, the low-temperature cold start engine process is triggered.

5. The method for controlling power generation of a low-temperature cold-start engine of a range-extended hybrid vehicle according to claim 4, characterized in that: Obtain the battery's discharge power and cell temperature, and determine whether the battery power is too low based on the battery's discharge power and cell temperature. This includes: The temperature of each battery cell is monitored in real time through the BMS system, and the real-time discharge power data of the battery is obtained through the BMS.

6. The method for controlling power generation of a low-temperature cold-start engine of a range-extended hybrid vehicle according to claim 1, characterized in that: If the battery power is too low, the vehicle will be requested to switch to high voltage. After the vehicle is controlled to enter the high voltage state, the engine will be started at low temperature to generate electricity. Specifically, the following steps are performed: Request BMS to power on high voltage. If the high voltage requirement is met, the BMS control relay is closed. After receiving the feedback of successful relay closure from BMS, the HCU controls the entire vehicle to enter the high voltage state.

7. The method for controlling power generation of a low-temperature cold-start engine of a range-extended hybrid vehicle according to claim 6, characterized in that: If the battery power is too low, the vehicle will be requested to switch to high voltage. After the vehicle is controlled to enter the high voltage state, the engine will be started at low temperature to generate electricity. Specifically, the following steps are performed: After requesting the BMS to supply high voltage to the vehicle, the BMS performs pre-charging. After the pre-charging is successful, the main positive relay is closed. Otherwise, a high voltage power-on timeout fault is reported.

8. The method for controlling power generation of a low-temperature cold-start engine of a range-extended hybrid vehicle according to claim 1, characterized in that: If the battery level is too low, the vehicle will be requested to switch to high voltage. After the vehicle is controlled to enter the high voltage state, the engine will be started at low temperature to generate electricity. Specifically, the following are included: After the entire vehicle is controlled to enter a high-voltage state, the engine is requested to start, the engine enters the torque control mode, quickly drives the engine to the target speed, and then enters the speed mode. During this process, the engine enters the start mode from the stop mode, and then enters the running mode. The engine outputs positive torque and enters the series power generation mode.

9. The method for controlling power generation of a low-temperature cold-start engine of a range-extended hybrid vehicle according to claim 1, characterized in that: The method further comprises: The BMS monitors the battery status to prevent overcharging or over-discharging; the HCU continuously monitors safety parameters throughout the process to ensure stable operation of the system.

10. A power generation control system for a low-temperature cold start engine of a range-extended hybrid vehicle, characterized in that: The system comprises: Wake-up module, used to wake up the power system controller and complete self-test; The low-temperature battery capacity judgment module is used to obtain the battery's discharge power and battery cell temperature, and determine whether the battery capacity is too low based on the battery's discharge power and battery cell temperature; The low-temperature engine starting module is used to request high voltage for the entire vehicle if the battery power is too low, and to start the engine at low temperature to generate electricity after controlling the entire vehicle to enter the high-voltage state.

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