CN114802195A

CN114802195A - Vehicle gear shifting method and device

Info

Publication number: CN114802195A
Application number: CN202210577212.0A
Authority: CN
Inventors: 杨云波; 韩令海; 张学锋; 赵鹏遥; 钟云锋; 郑通; 陈国栋; 赵永强; 刘元治; 宁甲奎
Original assignee: FAW Group Corp
Current assignee: FAW Group Corp
Priority date: 2022-05-25
Filing date: 2022-05-25
Publication date: 2022-07-29
Also published as: WO2023226638A1

Abstract

The invention discloses a gear shifting method and device for a vehicle. Wherein, the method comprises the following steps: selecting a target starting strategy under the condition that the current vehicle enters a starting mode in gear shifting; starting a current vehicle by adopting a target starting strategy, and acquiring the high-voltage motor state, the actual operation gear and the target gear of the current vehicle; determining a target gear shifting type based on the current high-voltage motor state of the vehicle, the actual operation gear and the target gear; and controlling the current vehicle to realize the starting of the engine in the gear shifting process by adopting a target gear shifting type. The invention solves the technical problems of low smoothness and poor safety of vehicle running caused by incapability of coordinating control of gear shifting and engine starting during vehicle gear shifting in the related technology.

Description

Vehicle gear shifting method and device

Technical Field

The invention relates to the technical field of automobile control, in particular to a gear shifting method and device for a vehicle.

Background

Hybrid vehicles have been the focus of research of various automobile manufacturers due to their low energy consumption, especially in recent years. And the hybrid vehicle has pure electric driving ability, and in the pure electric driving process, when the high-voltage battery ability is not enough or the torque required by the driver is increased, the engine needs to be started, but because the transient change of the engine in the starting process is large, the impact phenomenon of the vehicle in the driving process can be caused by poor control. For a hybrid vehicle with multiple gears, the gear shifting process of the transmission is also a working condition that the smoothness of the vehicle is easy to cause problems. And the engine is started simultaneously in the gear shifting process, and the influence factors of the engine and the engine are superposed to meet the smoothness of the whole vehicle, so that great challenge is existed in the coordination control of the engine and the engine.

In the related technology, the content of coordinated control of gear shifting and engine starting is avoided by some methods, the two are carried out at the same time, the gear shifting process or the engine starting process is determined by judging the state of a gear shifting clutch, if gear shifting is started first, gear shifting is finished first, then the engine is started, and if the engine starting (namely, a generator is started) is started first, the engine starting is finished first, and then the gear shifting is carried out. In another embodiment, the clutch state is maintained, so that the separation and combination frequency of the clutch is reduced, and the problem of poor service life and comfort of the clutch is solved; however, these methods have the disadvantages that if the gear is shifted after the start is completed, the gear shifting is delayed, the engine speed is high during the gear shifting, and overspeed may occur seriously, which affects the smoothness/comfort/safety of the vehicle; if the engine is started after gear shifting is finished, the starting time is late, the engine cannot provide power in time, and the power performance and smoothness of the whole vehicle are affected.

In view of the above problems, no effective solution has been proposed.

Disclosure of Invention

The embodiment of the invention provides a gear shifting method and device for a vehicle, and at least solves the technical problems that in the prior art, when the vehicle is shifted, gear shifting and engine starting cannot be coordinately controlled, so that the running smoothness of the vehicle is low and the safety is poor.

According to an aspect of an embodiment of the present invention, there is provided a shifting method of a vehicle, including: selecting a target starting strategy under the condition that the current vehicle enters a starting mode in gear shifting; starting the current vehicle by adopting the target starting strategy, and acquiring the high-voltage motor state, the actual operation gear and the target gear of the current vehicle; determining a target gear shifting type based on the high-voltage motor state, the actual operation gear and the target gear of the current vehicle; and controlling the current vehicle to realize the starting of the engine in the gear shifting process by adopting the target gear shifting type.

Optionally, before the current vehicle enters the shift start mode, the method further includes: acquiring the engine starting and stopping conditions of the current vehicle; judging whether to start the engine or not based on the engine starting and stopping conditions; judging whether the actual operation gear of the transmission is consistent with the target gear or not under the condition that the engine is determined to be started according to the engine starting and stopping conditions; and determining to enter the start-in-shift mode in the case that the actual operation gear and the target gear of the transmission are inconsistent.

Optionally, the step of starting the current vehicle by using the target start-up strategy includes: the method comprises the following steps that a low-voltage starter is adopted to drag an engine to rotate, when the rotating speed of the engine meets an oil injection ignition condition, the engine starts oil injection ignition, the rotating speed of the engine is controlled to be rushed to an idling rotating speed, and an idling running state is kept; controlling the engine to regulate the speed to a target rotating speed, and simultaneously controlling the separation clutch to start oil filling; and after the rotating speed of the engine reaches the target rotating speed, controlling the separating clutch to start to be combined so as to synchronize the rotating speed of the engine and the rotating speed of the high-voltage motor.

Optionally, the step of determining a target shift type based on the current high voltage motor state of the vehicle, the actual operating gear and the target gear comprises: determining that the target gear shifting type is a power upshift starting machine under the condition that the high-voltage motor state indicates that the torque of the high-voltage motor is greater than a first torque threshold value and the target gear is greater than the actual operating gear; determining that the target gear shifting type is a power downshift starting type under the condition that the high-voltage motor state indicates that the torque of the high-voltage motor is larger than a first torque threshold value and the target gear is smaller than the actual running gear; determining that the target gear shifting type is a sliding upshift starting machine under the condition that the high-voltage motor state indicates that the torque of the high-voltage motor is smaller than a first torque threshold value and the target gear is larger than the actual running gear; and determining that the target gear shifting type is a coasting and downshift starting machine under the condition that the high-voltage motor state indicates that the torque of the high-voltage motor is smaller than a first torque threshold value and the target gear is smaller than the actual running gear.

Optionally, in a case that the target shift type is a power upshift start or a coasting downshift start, the step of controlling the current vehicle to start the engine during the shift process by using the target shift type includes: controlling a shifting clutch under the target gear to fill oil; a shift clutch that controls torque transmission of the transmission to be switched from the shift clutch of the actual operating gear to the target gear; controlling the rotating speed of the motor, or controlling the rotating speed of a combination of the motor and the engine, and changing from the rotating speed of the transmission input shaft corresponding to the actual operating gear to the rotating speed of the transmission input shaft corresponding to the target gear; determining that the current vehicle completes power upshift gear shifting operation or coasting downshift gear shifting operation under the condition that the rotating speed of the transmission input shaft corresponding to the target gear is reached; and controlling the engine to smoothly start in the process of finishing the power upshift gear shifting operation or the sliding downshift gear shifting operation of the current vehicle.

Optionally, the step of controlling the engine to start smoothly during the power upshift operation of the current vehicle includes: under the condition of receiving an engine starting request, starting to control a low-pressure starter to start an engine to finish the first-stage engine starting, wherein in the process of controlling the low-pressure starter to start the engine, the rotating speed of the motor is controlled to reach the target rotating speed by the closed-loop feedback torque of the motor; controlling the low-pressure starter, and completing the combination of the separating clutch from the engine starting of the first stage to the third stage; controlling a low-pressure starter, and completing power source torque switching from a third-stage separation clutch combination to a fourth stage, wherein after the third-stage separation clutch combination is completed, acquiring the rotation speed of the transmission input shaft corresponding to the actual operation gear plus a second rotation speed deviation, acquiring the rotation speed of the transmission input shaft corresponding to the target gear plus the second rotation speed deviation, and acquiring the rotation speed of the transmission input shaft corresponding to the actual operation gear and the rotation speed of the transmission input shaft corresponding to the target gear according to a preset transition curve plus the second rotation speed deviation; and controlling the current vehicle to be completed by switching the torque of the power source in the fourth stage until the target rotating speed of the motor is recovered to a normal state so as to smoothly start the engine, wherein the rotating speed of the input shaft of the transmission corresponding to the target gear is controlled to be added with the first rotating speed deviation in the process of recovering to the normal state.

Optionally, the step of controlling the low-pressure starter to complete the disengagement clutch engagement from the first stage of engine cranking to the third stage comprises: after the low-pressure starter is controlled to finish the starting of the engine in the first stage, the low-pressure starter is controlled to start the engine to enter the engine synchronization stage in the second stage, and the target rotating speed of the engine is equal to the sum of the rotating speed of the motor and the preset rotating speed deviation; and controlling the target rotating speed of the engine to reach the target rotating speed of the motor in the rotating speed control process when the low-pressure starter starts the engine and enters a separating clutch combination stage of a third stage, and connecting the engine serving as a power input source to a power transmission system.

Optionally, the step of controlling the low-pressure starter to complete the power source torque transition from the third phase of the disconnect clutch to the fourth phase comprises: controlling the engine torque to increase at a maximum rate to the driving request torque after controlling the low-pressure starter to start the engine in a third stage of engaging the disconnect clutch; and determining a closed-loop feedback torque based on the driving request torque and the target rotating speed of the motor in the rotating speed control process of the gear shifting clutch, and controlling the rotating speed of the motor to reach the target rotating speed of the motor in the rotating speed control process of the gear shifting clutch by combining the closed-loop feedback torque.

Optionally, in a case that the target shift type is a power downshift starting machine or a coast upshift starting machine, the step of controlling the current vehicle to start the engine during the shift process by using the target shift type includes: controlling the rotating speed of a motor or the rotating speed of a combination of the motor and an engine, changing the rotating speed of an input shaft of a transmission corresponding to an actual operating gear to the rotating speed of the input shaft of the transmission corresponding to a target gear, and controlling the oil charge of a shifting clutch of the target gear; and controlling the torque transmission of the transmission to be switched from the gear shifting clutch of the actual running gear to the target gear clutch, so that the current vehicle finishes the power downshift gear shifting operation or the sliding upshift gear shifting operation, and further controlling the engine to smoothly start.

According to another aspect of the embodiments of the present invention, there is also provided a shifting apparatus of a vehicle, including: the selection unit is used for selecting a target starting strategy under the condition that the current vehicle enters a starting mode in gear shifting; the processing unit is used for starting the current vehicle by adopting the target starting strategy and acquiring the high-voltage motor state, the actual running gear and the target gear of the current vehicle; the first determination unit is used for determining a target gear shifting type based on the high-voltage motor state, the actual operation gear and the target gear of the current vehicle; and the control unit is used for controlling the current vehicle to realize the engine starting in the gear shifting process by adopting the target gear shifting type.

Optionally, the vehicle shifting device further comprises an obtaining unit, configured to obtain an engine start-stop condition of the current vehicle before the current vehicle enters a shift start mode; the first judgment unit is used for judging whether the engine needs to be started or not based on the engine starting and stopping conditions; the second judgment unit is used for judging whether the actual operation gear of the transmission is consistent with the target gear or not under the condition that the engine is determined to be started according to the engine starting and stopping conditions; and the second determination unit is used for determining to enter the starting mode in the gear shifting under the condition that the actual operation gear and the target gear of the transmission are inconsistent.

Optionally, the processing unit comprises: the first processing subunit is used for dragging the engine to rotate by adopting the low-pressure starter, starting oil injection ignition of the engine when the rotating speed of the engine meets an oil injection ignition condition, controlling the rotating speed of the engine to rush to an idle rotating speed and keeping an idle running state; the first control subunit is used for controlling the speed of the engine to be regulated to a target rotating speed and controlling the separation clutch to start oil charging; and the second control subunit is used for controlling the separation clutch to start to be combined after the rotating speed of the engine reaches the target rotating speed so as to synchronize the rotating speed of the engine and the rotating speed of the high-voltage motor.

Optionally, the first determination unit includes: the first determining subunit is used for determining that the target gear shifting type is a power upshift starting machine under the condition that the state of the high-voltage motor indicates that the torque of the high-voltage motor is greater than a first torque threshold value and the target gear is greater than the actual operating gear; the second determining subunit is used for determining that the target gear shifting type is a power downshift starting machine under the condition that the state of the high-voltage motor indicates that the torque of the high-voltage motor is greater than a first torque threshold value and the target gear is smaller than the actual operating gear; the third determining subunit is used for determining that the target gear shifting type is a sliding upshift starting machine under the condition that the state of the high-voltage motor indicates that the torque of the high-voltage motor is smaller than a first torque threshold value and the target gear is larger than the actual operating gear; and the fourth determining subunit is configured to determine that the target shift type is a coast downshift starting type when the state of the high-voltage motor indicates that the torque of the high-voltage motor is smaller than the first torque threshold and the target gear is smaller than the actual operating gear.

Optionally, the control unit further comprises: the third control subunit is used for controlling the oil filling of the shifting clutch under the target gear under the condition that the target gear shifting type is a power upshift starting machine or a coasting downshift starting machine; a fourth control subunit that controls torque transmission of the transmission to be switched from the shift clutch of the actual operating gear to the shift clutch of the target gear; the fifth control subunit is used for controlling the rotating speed of the motor, or controlling the rotating speed of the motor and engine assembly to change from the rotating speed of the transmission input shaft corresponding to the actual operating gear to the rotating speed of the transmission input shaft corresponding to the target gear; a fifth determining subunit, configured to determine that the current vehicle completes a power upshift shift operation or a coast downshift shift operation when a rotation speed of a transmission input shaft corresponding to the target gear is reached; and the sixth control subunit is used for controlling the engine to smoothly start in the process that the current vehicle completes the power upshift gear shifting operation or the coasting downshift gear shifting operation.

Optionally, the sixth control subunit further includes: the first control module is used for controlling the low-pressure starter to start the engine under the condition of receiving an engine starting request, and finishing the first-stage engine starting, wherein in the process of controlling the low-pressure starter to start the engine, the rotating speed of the motor is controlled to reach the target rotating speed by the closed-loop feedback torque of the motor; the second control module is used for controlling the low-pressure starter, and the clutch is combined from the completion of the engine start in the first stage to the separation in the third stage; the third control module is used for controlling the low-voltage starter, and completing power source torque switching from a third-stage separation clutch combination to a fourth stage, wherein after the third-stage separation clutch combination is completed, a second rotating speed deviation is added to a rotating speed of the transmission input shaft corresponding to an actual operating gear, a second rotating speed deviation is added to a rotating speed of the transmission input shaft corresponding to a target gear, and a second rotating speed deviation is added to the rotating speed of the transmission input shaft corresponding to the actual operating gear and the rotating speed of the transmission input shaft corresponding to the target gear according to a preset transition curve; and the fourth control module is used for controlling the current vehicle to be switched from the power source torque in the fourth stage to the target rotating speed of the motor to be recovered to the normal state so as to enable the engine to be started smoothly, wherein in the process of recovering to the normal state, the rotating speed of the transmission input shaft corresponding to the target gear is controlled to be added with the first rotating speed deviation.

Optionally, the second control module comprises: the first processing submodule is used for controlling the low-pressure starter to start the engine to enter a second-stage engine synchronization stage after the low-pressure starter is controlled to finish the engine starting in the first stage, and the target rotating speed of the engine is equal to the sum of the rotating speed of the motor and the preset rotating speed deviation; and the second processing submodule is used for controlling the target rotating speed of the engine to reach the target rotating speed of the motor in the rotating speed control process when the low-pressure starter starts the engine and enters a separating clutch combination stage of a third stage, and the engine is used as a power input source and is connected to the power transmission system.

Optionally, the third control module comprises: a first control submodule for controlling engine torque to increase at a maximum rate to a driving request torque after controlling the low-pressure starter to start the engine at a third stage of engagement of the disconnect clutch; and the determining submodule is used for determining a closed-loop feedback torque based on the driving request torque and the motor target rotating speed in the rotating speed control process of the gear shifting clutch, and controlling the rotating speed of the motor to reach the motor target rotating speed in the rotating speed control process of the gear shifting clutch by combining the closed-loop feedback torque.

Optionally, the control unit further comprises: the seventh control subunit is used for controlling the rotating speed of the motor or the rotating speed of a combination of the motor and the engine under the condition that the target gear shifting type is the power downshift starting machine or the coast upshift starting machine, changing the rotating speed of the transmission input shaft corresponding to the actual operating gear to the rotating speed of the transmission input shaft corresponding to the target gear, and controlling the oil charging of the gear shifting clutch of the target gear; and the eighth control subunit is used for controlling the torque transmission of the transmission to be switched from the gear shifting clutch of the actual running gear to the target gear clutch, so that the current vehicle finishes the power downshift gear shifting operation or the sliding upshift gear shifting operation, and further the engine is controlled to be smoothly started.

According to the method, under the condition that a current vehicle enters a start-up mode in gear shifting, a target start-up strategy is selected, then the current vehicle is started by adopting the target start-up strategy, the high-voltage motor state, the actual operation gear and the target gear of the current vehicle are obtained, then a target gear shifting type is determined based on the high-voltage motor state, the actual operation gear and the target gear of the current vehicle, and finally the target gear shifting type is adopted to control the current vehicle to realize engine starting in the gear shifting process. In the method, a start strategy is selected firstly, then the gear shifting type is determined according to the state of the vehicle and the target gear requirement, and the engine is controlled to start according to the gear shifting type, so that the purpose of coordinated gear shifting and engine starting coordinated control is achieved, the technical effects of improving the smoothness, comfort and safety of the vehicle in the gear shifting process of the vehicle are achieved, and the technical problems of low smoothness and poor safety of vehicle driving caused by the fact that the gear shifting and the engine starting cannot be coordinated and controlled in the gear shifting process of the vehicle in the related technology are solved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:

FIG. 1 is a flow chart of an alternative vehicle shifting method according to an embodiment of the present invention;

FIG. 2 is a flow chart of an alternative method of start-up control in shifting according to an embodiment of the present invention;

FIG. 3 is a block diagram of an alternative hybrid vehicle shifting system in the P2 configuration according to an embodiment of the present invention;

FIG. 4 is a flow chart of an alternative low pressure starter pull-up mode start-up procedure in accordance with an embodiment of the present invention;

FIG. 5 is a flowchart of an alternative power upshift process according to an embodiment of the present invention;

FIG. 6 is a flowchart of an alternative low-pressure starter engine starting control process according to an embodiment of the present invention;

FIG. 7 is a graphical illustration of speed and torque changes during an alternative power upshift startup control according to an embodiment of the present invention;

FIG. 8 is a schematic illustration of an alternative power downshift and coast upshift shift procedure in accordance with an embodiment of the present invention;

FIG. 9 is a schematic illustration of an alternative coast downshift shift procedure in accordance with an embodiment of the present invention;

FIG. 10 is a schematic illustration of an alternative vehicle shifting apparatus according to an embodiment of the present invention.

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, shall fall within the protection scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The invention can be applied to various automatic driving systems/software/products, in particular to an electric vehicle or a hybrid vehicle which mainly comprises a new energy vehicle, for example, a hybrid vehicle with a P2 configuration, can realize a method for starting an engine in the gear shifting process of the hybrid vehicle, enables the engine to be started and gear shifted to be coordinately controlled, provides power for the engine according to the gear shifting requirement in time, and ensures the smoothness/comfort/safety of the hybrid vehicle.

The new energy vehicle comprises an electric drive system, a power supply system, an auxiliary system and the like, wherein the electric drive system comprises an electronic controller, a power converter, a motor, a mechanical transmission device and wheels; the power supply system comprises a power supply, an energy management system and a charger; the auxiliary system comprises an auxiliary power source, a power steering system, a navigation system, an air conditioner, a lighting and defrosting device, a wiper, a radio and the like.

The invention provides a method for controlling the starting of an engine in the gear shifting process of a vehicle, which is characterized in that when an engine starting request occurs in the gear shifting process, a proper starting mode is selected firstly, and then different control strategies are formulated according to different gear shifting types by taking the rotating speed of the engine, the rotating speed of a motor and the rotating speed of an input shaft of a transmission as control targets, so that the coordinated control of the starting of the engine in the gear shifting process is realized. The method is beneficial to improving the smoothness of the whole vehicle when the engine is started in the gear shifting process, further improving the dynamic comfort and the safety performance of the whole vehicle, improving the satisfaction degree of customers on the whole vehicle product, and being beneficial to improving the market competitiveness of the product.

The present invention will be described in detail with reference to examples.

Example one

In accordance with an embodiment of the present invention, there is provided an embodiment of a method of shifting gears in a vehicle, it being noted that the steps illustrated in the flowchart of the drawings may be performed in a computer system such as a set of computer executable instructions and that, although a logical order is illustrated in the flowchart, in some cases, the steps illustrated or described may be performed in an order different than presented herein.

FIG. 1 is a flow chart of an alternative vehicle shifting method according to an embodiment of the present invention, as shown in FIG. 1, including the steps of:

step S101, selecting a target starting strategy under the condition that the current vehicle enters a starting mode in gear shifting;

step S102, starting a current vehicle by adopting a target starting strategy, and acquiring the high-voltage motor state, the actual operation gear and the target gear of the current vehicle;

step S103, determining a target gear shifting type based on the high-voltage motor state, the actual operation gear and the target gear of the current vehicle;

and step S104, controlling the current vehicle to realize the engine starting in the gear shifting process by adopting the target gear shifting type.

Through the steps, under the condition that the current vehicle enters a start-up mode in gear shifting, a target start-up strategy is selected, then the current vehicle is started by adopting the target start-up strategy, the high-voltage motor state, the actual operation gear and the target gear of the current vehicle are obtained, then a target gear shifting type is determined based on the high-voltage motor state, the actual operation gear and the target gear of the current vehicle, and finally the target gear shifting type is adopted to control the current vehicle to realize the starting of the engine in the gear shifting process. In this embodiment, a start strategy is selected first, then a gear shifting type is determined according to a state of a vehicle and a target gear requirement, and an engine is controlled to start according to the gear shifting type, so that the purpose of coordinated gear shifting and engine start coordinated control is achieved, and therefore, the technical effects of improving smoothness, comfort and safety of the vehicle in the gear shifting process of the vehicle are achieved, and the technical problems of low smoothness and poor safety of vehicle driving caused by the fact that gear shifting and engine start cannot be coordinated control during gear shifting of the vehicle in the related art are solved.

The following describes embodiments of the present invention in detail with reference to the above-described respective implementation steps.

As an optional implementation manner of this embodiment, before the current vehicle enters the shift start mode, the method further includes: acquiring the engine start-stop condition of the current vehicle; judging whether to start the engine or not based on the engine starting and stopping conditions; judging whether the actual running gear of the transmission is consistent with the target gear or not under the condition that the engine is determined to be started under the engine starting and stopping conditions; in the case where the actual operating gear of the transmission and the target gear do not coincide, it is determined to enter a start-in-shift mode.

When a vehicle enters a gear-shifting start mode, because the engine needs to be started when the capacity of a high-voltage battery is insufficient or the torque required by a driver is increased in the running process of the vehicle, namely when a target gear selected by driving is different from an actual gear, or when the vehicle is a pure electric vehicle or a hybrid electric vehicle, and the capacity of the battery is insufficient, the engine can be started, the starting and stopping conditions of the engine of the current vehicle can be obtained, and when the starting and stopping conditions of the engine determine that the engine needs to be started, whether the actual running gear and the target gear of the transmission are consistent or not can be judged; in the case where the actual operating gear of the transmission and the target gear do not coincide, it is determined to enter a start-in-shift mode.

And step S101, selecting a target starting strategy under the condition that the current vehicle enters a starting mode in gear shifting.

Taking the P2 configuration hybrid vehicle (referring to a hybrid vehicle with an electric machine placed after the clutch and before the transmission) as an example, the start-up strategy may include two start modes, one with a low-pressure starter and one with a high-pressure electric machine. For starting the engine in the gear shifting process, in order to avoid worsening of the smoothness of the whole vehicle in the gear shifting process caused by the rapid change of torque and rotating speed in the engine dragging and ignition processes, the engine can be started by adopting a low-pressure starter, and because the separation clutch is in a separation state in the engine dragging and ignition processes, transient impact in the engine starting process can not be transmitted to a wheel end, so that the smoothness of the vehicle is ensured.

And S102, starting the current vehicle by adopting a target starting strategy, and acquiring the high-voltage motor state, the actual operation gear and the target gear of the current vehicle.

Optionally, the step of starting the current vehicle by using the target startup strategy includes: the low-pressure starter is adopted to drag the engine to rotate, when the rotating speed of the engine meets the oil injection ignition condition, the engine starts oil injection ignition, the rotating speed of the engine is controlled to be rushed up to the idling rotating speed, and the idling running state is kept; controlling the engine to regulate the speed to a target rotating speed, and simultaneously controlling the separation clutch to start oil filling; and after the rotating speed of the engine reaches the target rotating speed, controlling the separating clutch to start to be combined so as to synchronize the rotating speed of the engine and the rotating speed of the high-voltage motor.

In the process of starting the engine by the low-pressure starter, the control process can be divided into the following four processes:

a) the starting process of the engine comprises the following steps: the low-pressure starter drives the engine to rotate, when the rotating speed of the engine meets the oil injection ignition condition, the engine starts oil injection ignition, the rotating speed is increased to the idling rotating speed, and the idling running state is kept;

b) and (3) rotating speed synchronization process: the engine automatically adjusts the speed to the target speed set based on the high-voltage motor speed, and the separation clutch starts to charge oil to prepare for the clutch combination process in the next stage.

c) The process of separating the clutch is as follows: after the rotating speed of the engine reaches the target rotating speed, the separating clutch is combined at a certain speed, and finally the synchronization of the rotating speed of the engine and the rotating speed of the high-voltage motor is realized.

d) The power source torque switching process: a process of switching the output of power from the motor torque to the engine torque.

And step S103, determining a target gear shifting type based on the current high-voltage motor state, the actual operation gear and the target gear of the vehicle.

Optionally, the step of determining the target shift type based on the current high-voltage motor state of the vehicle, the actual operating gear and the target gear includes: determining that the target gear shifting type is a power upshift starting machine under the condition that the high-voltage motor state indicates that the torque of the high-voltage motor is greater than a first torque threshold value and the target gear is greater than an actual operating gear; determining the target gear shifting type as a power downshift starting machine under the condition that the high-voltage motor state indicates that the torque of the high-voltage motor is larger than a first torque threshold value and the target gear is smaller than an actual operating gear; determining that the target gear shifting type is a sliding upshift starting machine under the condition that the high-voltage motor state indicates that the torque of the high-voltage motor is smaller than a first torque threshold value and the target gear is larger than an actual running gear; and under the condition that the high-voltage motor state indicates that the torque of the high-voltage motor is smaller than a first torque threshold value and the target gear is smaller than the actual running gear, determining that the target gear shifting type is the coasting downshift starting machine.

The starting control in which type of gear shifting is performed can be judged according to the state, the actual gear and the target gear of the high-voltage motor, and specifically, when the torque of the high-voltage motor is greater than a first torque threshold value and the target gear is greater than the actual gear, power is selected to be used for starting control in an up-shifting mode; when the torque of the high-voltage motor is larger than a first torque threshold value and the target gear is smaller than an actual gear, selecting power downshift starting control; when the torque of the high-voltage motor is smaller than a first torque threshold value and the target gear is larger than an actual gear, selecting sliding gear-up starting control; and selecting the sliding downshift starting control when the torque of the high-voltage motor is smaller than the first torque threshold and the target gear is smaller than the actual gear.

Optionally, in a case where the target shift type is a power upshift start or a coast downshift start, the step of controlling the current vehicle to start the engine during the shift using the target shift type includes: controlling oil filling of the shifting clutch under the target gear; a shift clutch that controls torque transmission of the transmission to be switched from the shift clutch of the actual operating gear to the target gear; controlling the rotating speed of the motor, or controlling the rotating speed of a motor and engine combination, and changing from the rotating speed of the transmission input shaft corresponding to the actual operating gear to the rotating speed of the transmission input shaft corresponding to the target gear; determining that the current vehicle completes power upshift gear shifting operation or coasting downshift gear shifting operation under the condition that the rotating speed of the transmission input shaft corresponding to the target gear is reached; and controlling the engine to smoothly start in the process of finishing the power upshift gear shifting operation or the sliding downshift gear shifting operation of the current vehicle.

In the process of power gear-up and gear-shifting, the process can be divided into three steps, a), the gear-shifting clutch is filled with oil: filling oil to the gear shifting clutch of the target gear to prepare for clutch torque switching of the next stage; b) shifting clutch torque switching: the torque transmission of the transmission is switched from the gear shifting clutch of the actual gear to the target gear clutch, so that the speed ratio is switched; c) and (3) power source rotating speed regulation: the rotation speed of the motor (the separation clutch is in a separation state) or the rotation speed of the motor and engine combination (the separation clutch is in a combination state) is changed from the rotation speed of the transmission input shaft corresponding to the actual gear to the rotation speed of the transmission input shaft corresponding to the target gear. When the rotating speed of the input shaft of the transmission corresponding to the target gear is reached, the fact that the current vehicle completes power upshift gear shifting operation is determined, and the engine can be controlled to smoothly start in the process that the current vehicle completes the power upshift gear shifting operation, namely the engine start control process in the process of power upshift gear shifting is carried out.

In the process of sliding, downshifting and shifting, the process of sliding, downshifting and shifting is also divided into three steps, a) the shifting clutch is filled with oil: filling oil to the gear shifting clutch of the target gear to prepare for clutch torque switching of the next stage; b) shifting clutch torque switching: the torque transmission of the transmission is switched from the gear shifting clutch of the actual gear to the target gear clutch, so that the speed ratio is switched; c) and (3) power source rotating speed regulation: the rotation speed of the motor (the separation clutch is in a separation state) or the rotation speed of the motor and engine combination (the separation clutch is in a combination state) is changed from the rotation speed of the transmission input shaft corresponding to the actual gear to the rotation speed of the transmission input shaft corresponding to the target gear. When the speed of the input shaft of the transmission corresponding to the target gear is reached, the fact that the current vehicle completes the sliding downshift operation is determined, and the engine can be controlled to smoothly start in the process that the current vehicle completes the sliding downshift gear shifting operation, namely the engine start control process in the process of performing the sliding downshift gear shifting operation.

The recovery process functions as follows: and after the starting process is finished, the sliding friction rotating speed of the shifting clutch is recovered to the first rotating speed deviation from the second rotating speed deviation, and normal driving and shifting control are carried out.

The engine starting control process in the sliding downshift gear shifting process is the same as that in the sliding upshift gear shifting process, and the control content of each process is also the same.

The following describes in detail the steps of controlling the engine to start smoothly during the power upshift operation of the vehicle.

An alternative step of controlling a smooth engine start during a current vehicle power upshift operation, comprising: under the condition of receiving an engine starting request, starting to control a low-pressure starter to start an engine to finish the first-stage engine starting, wherein in the process of controlling the low-pressure starter to start the engine, the rotating speed of the motor is controlled to reach the target rotating speed by the closed-loop feedback torque of the motor; controlling the low-pressure starter, and completing the combination of the separating clutch from the engine starting of the first stage to the third stage; controlling a low-pressure starter, and completing power source torque switching from a third-stage separation clutch combination to a fourth stage, wherein after the third-stage separation clutch combination is completed, acquiring the rotation speed of the transmission input shaft corresponding to the actual operation gear plus a second rotation speed deviation, acquiring the rotation speed of the transmission input shaft corresponding to the target gear plus the second rotation speed deviation, and acquiring the rotation speed of the transmission input shaft corresponding to the actual operation gear and the rotation speed of the transmission input shaft corresponding to the target gear according to a preset transition curve plus the second rotation speed deviation; and controlling the current vehicle to be completed by switching the torque of the power source in the fourth stage until the target rotating speed of the motor is recovered to a normal state so as to smoothly start the engine, wherein the rotating speed of the input shaft of the transmission corresponding to the target gear is controlled to be added with the first rotating speed deviation in the process of recovering to the normal state.

The engine smoothly starts in the power upshift and gear shift process: the method can be used for starting four stages of a starting process of a low-pressure starter, namely a first-stage engine starting process, a second-stage rotating speed synchronization process, a third-stage separating clutch combination process and a fourth-stage power source torque switching process.

Specifically, the four control processes of starting the engine by the low-voltage starter selected according to the starting mode can be realized by specifically controlling the shift clutch, the rotating speed of the high-voltage motor and the rotating speed of the engine, fig. 6 is a flow chart of an optional control process of starting the engine by the low-voltage starter according to the embodiment of the invention, as shown in fig. 6, the control process of power upshift and shift starting can be specifically divided into four control stages, and the four control stages can be a pre-control process, a motor rotating speed control process, a rotating speed control process of the shift clutch and a recovery process. FIG. 7 is a schematic diagram of the rotational speed and torque changes during an alternative power upshift startup control process according to an embodiment of the present invention, and the steps of controlling smooth engine startup during a current vehicle power upshift shift operation are described with reference to the rotational speed and torque changes during the power upshift startup control process of FIG. 7 for the four control phases of FIG. 6 and the four phases of the startup process of the low-pressure starter:

a) the pre-control process comprises the following steps: the engine starting is completed from the first stage of receiving the engine starting request to the starting of the engine by the low-pressure starter, and the actions of each part are as follows: an engine: the low-pressure starter drags the engine to rotate, when the rotating speed of the engine meets the oil injection ignition condition, the engine starts oil injection ignition, and after the rotating speed is up-rushed to the idling rotating speed, the idling running state is kept; a motor: outputting torque according to the driving request torque; a shifting clutch: the motor torque is used as a feedforward torque and a closed loop feedback torque of a difference value between the motor rotating speed and the target rotating speed of the motor in the pre-control process, and the rotating speed of the motor is controlled to reach the target rotating speed of the motor in the pre-control process, wherein the target rotating speed of the motor in the pre-control process can specifically refer to the rotating speed of an input shaft of a transmission corresponding to an actual gear plus a first rotating speed deviation. The pre-control process has the following functions: the engine is started by the low-pressure starter, and because the separation clutch is in a separation state, the influence factors of the starting process of the engine cannot be transmitted to the 9-wheel end, so that the shifting clutch also keeps the control of the original shifting process.

b) The process of controlling the rotating speed of the motor: from the first stage of starting the engine by the low-pressure starter to the third stage of combining the separating clutch, the actions of each part are as follows: an engine: the engine carries out autonomous speed regulation control to enable the rotating speed of the engine to reach the target rotating speed of the engine in the rotating speed control process of the motor; a motor: controlling the motor rotating speed to reach the motor target rotating speed in the motor control rotating speed process by taking the driving request torque as a feedforward torque and a closed loop feedback torque of a difference value between the motor rotating speed and the motor target rotating speed in the motor control rotating speed process; a shifting clutch: open loop control is input as clutch engagement torque based on the driving request torque.

c) The process of controlling the rotating speed of the gear shifting clutch is as follows: from the completion of the combination of the separating clutch at the third stage of starting the engine by the low-pressure starter to the completion of the torque switching of the power source at the fourth stage, the actions of all the components are as follows: an engine: the engine torque increases to the driving request torque at the maximum rate achievable; a motor: the motor torque is equal to the driving request torque minus the engine torque; a shifting clutch: the motor speed is controlled to reach the motor target speed in the speed control process of the gear shifting clutch by taking the driving request torque as a feed-forward torque and a closed loop feedback torque of a difference value of the motor speed and the motor target speed in the speed control process of the gear shifting clutch.

d) And (3) recovery process: and recovering the target rotating speed of the motor to a normal state from the completion of the torque switching of the fourth section of the power source to the completion of the target rotating speed of the motor, wherein the target rotating speed of the motor in the recovery process is the sum of the rotating speed of the input shaft of the target transmission and the first rotating speed deviation in the speed regulation stage corresponding to the target gear.

Optionally, the step of controlling the low-pressure starter to complete the engagement of the disconnect clutch from the first stage of engine cranking to the third stage comprises: after the low-pressure starter is controlled to finish the starting of the engine in the first stage, the low-pressure starter is controlled to start the engine to enter the engine synchronization stage in the second stage, and the target rotating speed of the engine is equal to the sum of the rotating speed of the motor and the preset rotating speed deviation; and controlling the target rotating speed of the engine to reach the target rotating speed of the motor in the rotating speed control process when the low-pressure starter starts the engine and enters a separating clutch combination stage of a third stage, and connecting the engine serving as a power input source to a power transmission system.

The target rotating speed of the engine in the rotating speed control process of the motor specifically refers to the rotating speed synchronization stage of the engine in the second stage of starting the engine by the low-voltage starter, and the target rotating speed of the engine is equal to the rotating speed of the motor plus a third rotating speed deviation in the rotating speed control process of the motor; in the clutch separating and combining stage of the third stage of starting the engine by the low-voltage starter, the target rotating speed of the engine is equal to the target rotating speed of the motor in the rotating speed controlling process of the motor.

Optionally, the step of controlling the low-pressure starter to complete the power source torque shift from the third stage of the disconnect clutch to the fourth stage includes: controlling the engine torque to increase to the driving request torque at a maximum rate after the off-clutch engagement of the third stage completes the off-clutch engagement of the third stage; determining a closed-loop feedback torque based on the driving request torque and the motor target rotating speed in the rotating speed control process of the gear shifting clutch, and controlling the rotating speed of the motor to reach the motor target rotating speed in the rotating speed control process of the gear shifting clutch by combining the closed-loop feedback torque, wherein the calculating step of the motor target rotating speed in the rotating speed control process of the gear shifting clutch comprises the following steps of: acquiring the rotation speed of the transmission input shaft corresponding to the actual operation gear plus a second rotation speed deviation; acquiring the rotation speed of the input shaft of the transmission corresponding to the target gear plus a second rotation speed deviation; and acquiring the rotating speed of the transmission input shaft corresponding to the actual operating gear and the rotating speed of the transmission input shaft corresponding to the target gear, and adding a second rotating speed deviation according to a preset transition curve.

The above process is explained with reference to the components of the driving vehicle, from the completion of the clutch disengagement at the third stage of starting the engine by the low-pressure starter to the completion of the torque switching of the power source at the fourth stage, the actions of the components are as follows: an engine: the engine torque increases to the driving request torque at the maximum rate achievable; a motor: the motor torque is equal to the driving request torque minus the engine torque; a shifting clutch: the motor rotating speed is controlled to reach the motor target rotating speed in the rotating speed control process of the gear shifting clutch by taking the driving request torque as the feedforward torque and the closed loop feedback torque of the difference value of the motor rotating speed and the motor target rotating speed in the rotating speed control process of the gear shifting clutch, namely the motor rotating speed is controlled to reach the motor target rotating speed in the motor control rotating speed process by taking the driving request torque as the feedforward torque and the closed loop feedback torque of the difference value of the motor rotating speed and the motor target rotating speed in the motor control rotating speed process.

The target rotating speed of the motor in the rotating speed control process of the gear shifting clutch can be specifically defined as that before the rotating speed regulating process of the power source in the third stage of power upshift is started, the rotating speed of the transmission input shaft corresponding to the actual gear is added with a second rotating speed deviation; after the power source rotating speed regulating process in the third power gear-up stage is finished, the rotating speed of the transmission input shaft corresponding to the target gear is added with a second rotating speed deviation; in the process of regulating the rotating speed of the power source in the third stage of power upshift; and adding a second rotating speed deviation to the rotating speed of the transmission input shaft corresponding to the actual gear and the rotating speed of the transmission input shaft corresponding to the target gear according to a preset transition curve.

The function of the gear shifting clutch in the process of controlling the rotating speed is as follows: after the clutch is engaged, the torque of the power source is switched. Because the torque response characteristics of the engine and the motor are different, the condition of unsmooth output torque may exist in the power source torque switching process, and the smoothness of the vehicle can be ensured by still keeping the large speed difference of the input shafts of the power source and the transmission rotating speed and the mode that the torque of the gear shifting clutch adopts the driving required torque as the feedforward torque. And the rotational inertia of the power source is determined again because the separating clutch is combined, and the rotating speed of the motor can be controlled to reach the target rotating speed through the shifting clutch so as to prepare for the shifting process to be recovered to the normal state.

Optionally, in the case that the target shift type is a power downshift start or a coast upshift start, the step of controlling the current vehicle to start the engine during the shift process by using the target shift type includes: controlling the rotating speed of a motor or the rotating speed of a combination of the motor and an engine, changing the rotating speed of an input shaft of a transmission corresponding to an actual operating gear to the rotating speed of the input shaft of the transmission corresponding to a target gear, and controlling the oil charge of a shifting clutch of the target gear; and controlling the torque transmission of the transmission to be switched from the gear shifting clutch of the actual running gear to the target gear clutch, so that the current vehicle finishes the power downshift gear shifting operation or the sliding upshift gear shifting operation, and further controlling the engine to smoothly start.

In the power downshift gear shifting process, the method is divided into two steps: a) and (3) power source rotating speed regulation: the rotating speed of the motor (the separation clutch is in a separation state) or the rotating speed of the motor and engine assembly (the separation clutch is in a combination state) is changed from the rotating speed of the transmission input shaft corresponding to the actual gear to the rotating speed of the transmission input shaft corresponding to the target gear; meanwhile, the gear shifting clutch of the target gear is filled with oil to prepare for the torque switching of the clutch at the next stage; b) shifting clutch torque switching: the torque transmission of the transmission is switched from the gear shifting clutch of the actual gear to the target gear clutch, so that the speed ratio is switched. The engine starting control process in the power downshift gear shifting process is the same as the engine starting process in the power upshift gear shifting process, and the control content of each process is also the same.

In the process of sliding gear-up and gear-shifting, the process of sliding gear-up and gear-shifting is divided into two steps, a) power source rotating speed regulation: the rotating speed of the motor (the separation clutch is in a separation state) or the rotating speed of the motor and engine assembly (the separation clutch is in a combination state) is changed from the rotating speed of the transmission input shaft corresponding to the actual gear to the rotating speed of the transmission input shaft corresponding to the target gear; meanwhile, the gear shifting clutch of the target gear is filled with oil to prepare for the torque switching of the clutch at the next stage; b)

shifting clutch torque switching: the torque transmission of the transmission is switched from the gear shifting clutch of the actual gear to the target gear clutch, so that the speed ratio is switched.

And starting the engine in the process of sliding up-shifting and shifting gears. The engine starting control process in the coasting upshift and gear shifting process is the same as that in the power upshift and gear shifting process, but the calculation of the target rotating speed in the control content is different, and the difference details are as follows: a) the difference of the pre-control process is as follows: in the engine starting control process in the sliding gear-up and gear-shifting process, the target rotating speed of a motor in the process is pre-controlled, specifically, the target rotating speed is obtained by subtracting a first rotating speed deviation from the rotating speed of an input shaft of a transmission corresponding to an actual gear. b) The difference of the motor speed control process is as follows: in the engine starting control process in the sliding gear-up and gear-shifting process, the target rotating speed of the motor is controlled by the motor in the rotating speed control process, specifically, the target rotating speed is obtained by subtracting a second rotating speed deviation from the rotating speed of the transmission input shaft corresponding to the actual gear.

The target rotating speed of the engine in the rotating speed control process of the motor specifically refers to the engine synchronization stage of the second stage when the low-voltage starter starts the engine, and the target rotating speed of the engine is equal to the rotating speed of the motor minus the third rotating speed deviation in the rotating speed control process of the motor. In the clutch separating and combining stage of the third stage of starting the engine by the low-voltage starter, the target rotating speed of the engine is equal to the target rotating speed of the motor in the motor pre-control process in the rotating speed control process of the motor;

the motor control rotating speed process has the following functions: the engine speed synchronization and clutch combination process is to connect the engine as the power input source into the power transmission system, in order to avoid the influence on the wheel end of the vehicle, the torque transmission direction is ensured by the target speed control mode that the engine speed < the motor speed < the transmission input shaft speed, and the torque of the gear shifting clutch is ensured to be stable only by the open loop control mode that the driving request torque is used as the input, thereby ensuring the smoothness of the vehicle.

According to the control method for starting the engine in the vehicle gear shifting process, the engine starting request occurs in the gear shifting process, firstly, a proper starting mode is selected, secondly, the engine rotating speed, the motor rotating speed and the transmission input shaft rotating speed are taken as control targets, different control strategies are formulated according to different gear shifting types, and coordinated control of engine starting in the gear shifting process is achieved. The smoothness of the whole vehicle when the engine is started in the gear shifting process is improved, and the dynamic comfort of the whole vehicle is further improved.

The invention is described below in connection with an alternative embodiment.

Example two

In the embodiment of the present invention, an alternative vehicle gear shifting method is described with reference to a schematic hybrid vehicle architecture, which can perform start control during gear shifting, that is, start control of an engine during gear shifting, fig. 2 is a flowchart of an alternative gear shifting start control method according to the embodiment of the present invention, and as shown in fig. 2, the gear shifting start control process is as follows:

(1) and (3) judging the starting working condition in gear shifting: whether a start control mode in gear shifting is started can be judged according to the actual gear, the target gear and the start request;

(2) selecting a starting mode: selecting a specific starting mode after entering a starting control mode in gear shifting;

(3) after the start-up mode is determined, determining a gear shifting type: and judging which type of gear shifting is to be performed in a starting control process according to the state, the actual gear and the target gear of the high-voltage motor, wherein the gear shifting type can be power upshifting gear shifting, power downshifting gear shifting, sliding upshifting gear shifting and sliding downshifting gear shifting.

(4) According to the gear shifting type, entering a start control process corresponding to the gear shifting type: the starting control mode can be power upshift starting control, power downshift starting control, sliding upshift starting control and sliding downshift starting control, wherein,

controlling power gear-up starting: the engine starting control process can be the engine starting control process in the power upshift and gear shifting process;

controlling power gear reduction and starting: the engine starting control process can be used in the power downshift gear shifting process;

and (3) sliding gear-up starting control: the engine starting control process can be the engine starting control process in the sliding gear-up and gear-shifting process;

controlling sliding, gear-down and starting: the engine starting control process in the coasting downshift gear shifting process can be adopted.

The embodiment provides an engine starting control method in a vehicle shifting process, which can be used for a hybrid vehicle in a P2 configuration, and can also be used for other types of hybrid vehicles or electric vehicles, and hybrid vehicles in other configurations, and fig. 3 is a structural diagram of an alternative hybrid vehicle shifting system in a P2 configuration according to an embodiment of the invention, as shown in fig. 3:

first, the numerals in the drawings and structural meanings corresponding to the numerals will be explained:

in the figure: 1-a low-voltage starter; 2-an engine; 3-disengaging the clutch; 4-a high voltage motor; 5-a shifting clutch; 6-transmission input shaft; 7-a transmission; 8-a transmission output shaft; 9-vehicle wheels.

The shifting clutch is a clutch mechanism between the transmission and the power input source, and does not mean a specific clutch. For example: for a DCT Transmission (Dual-clutch Transmission), the shifting clutches represent both odd-and even-numbered clutches; for an AT Transmission (Automatic Transmission), a shifting clutch represents a combination of a clutch and a brake of a planetary gear mechanism for realizing different speed ratios, a torque converter and a lockup clutch thereof; for an AMT (Automated Manual Transmission), the shifting clutch represents a single clutch in the Transmission; in a CVT Transmission (Continuously Variable Transmission), a shift clutch represents a hydraulic torque converter and a lockup clutch thereof.

The transmission input shaft is a transmission input shaft calculated by the transmission according to the rotating speed of an output shaft and a gear speed ratio, and does not represent a specific real shaft. For example: the rotating speed of the target gear input shaft of the transmission is equal to the rotating speed of the output shaft of the transmission multiplied by the speed ratio of the target gear; the actual transmission gear input shaft speed is equal to the transmission output shaft speed multiplied by the actual gear ratio.

The P2 configuration hybrid power has two main starting modes: one is started by a low-voltage starter, and the other is started by a high-voltage motor. For starting the engine in the gear shifting process, in order to avoid worsening of the smoothness of the whole vehicle in the gear shifting process caused by the rapid change of torque and rotating speed in the dragging and igniting processes of the engine, the engine is started by adopting a low-pressure starter, and because a separation clutch is in a separation state in the dragging and igniting processes of the engine, transient impact in the starting process of the engine cannot be transmitted to a wheel end, so that the smoothness of the vehicle is ensured.

The following is a detailed description of each step of the start-up control process in shifting.

1. And judging the starting working condition in gear shifting.

And in the process of starting the engine in the gear shifting, judging whether to enter a starting control mode in the gear shifting according to the actual gear, the target gear and the starting request, specifically, judging whether the actual gear and the target gear of the transmission are consistent when the whole vehicle control unit judges and determines to start the engine according to the starting and stopping conditions of the engine, and if not, entering the starting control mode in the gear shifting.

2. And selecting a starting mode.

In the starting mode selection, a specific starting mode is selected, and specifically, the starting mode can be a starting mode in which a low-pressure starter is selected to start the engine. Fig. 4 is a flowchart of an alternative starting procedure of a low-pressure starter starting mode according to an embodiment of the present invention, in which the control procedure of the starting procedure of the low-pressure starter starting engine is divided into the following four procedures, as shown in fig. 4:

1) the starting process of the engine comprises the following steps: the low-pressure starter drives the engine to rotate, when the rotating speed of the engine meets the oil injection ignition condition, the engine starts oil injection ignition, the rotating speed is increased to the idling rotating speed, and the idling running state is kept;

2) and (3) rotating speed synchronization process: the engine automatically adjusts the speed to the target speed set based on the high-voltage motor speed, and the separation clutch starts to charge oil to prepare for the clutch combination process in the next stage.

3) The process of separating the clutch is as follows: after the rotating speed of the engine reaches the target rotating speed, the separating clutch is combined at a certain speed, and finally the synchronization of the rotating speed of the engine and the rotating speed of the high-voltage motor is realized.

4) The power source torque switching process: a process of switching the output of power from the motor torque to the engine torque.

3. And determining the type of gear shifting.

In the gear shifting type determination, judging which type of gear shifting is to be started for controlling according to the state of the high-voltage motor, the actual gear and the target gear, specifically, selecting power to upshift and start when the torque of the high-voltage motor is greater than a first torque threshold and the target gear is greater than the actual gear; when the torque of the high-voltage motor is larger than a first torque threshold value and the target gear is smaller than an actual gear, selecting power downshift starting control; when the torque of the high-voltage motor is smaller than a first torque threshold value and the target gear is larger than an actual gear, selecting sliding gear-up starting control; and selecting the sliding downshift starting control when the torque of the high-voltage motor is smaller than the first torque threshold and the target gear is smaller than the actual gear.

4. And starting the control process of the entered gear shifting type according to the determined gear shifting type in the gear shifting type determination.

The shift-in-shift start control for each shift type is described in detail below.

4.1 power gear-up starting control.

1) And (5) a power upshift gear shifting process. Fig. 5 is a flow chart of an alternative power upshift process according to an embodiment of the present invention, as shown in fig. 5, the power upshift process, divided into three steps,

a) oil filling of the gear shifting clutch: filling oil to the gear shifting clutch of the target gear to prepare for clutch torque switching of the next stage;

b) shifting clutch torque switching: the torque transmission of the transmission is switched from the gear shifting clutch of the actual gear to the target gear clutch, so that the speed ratio is switched;

c) and (3) power source rotating speed regulation: the rotation speed of the motor (the separation clutch is in a separation state) or the rotation speed of the motor and engine combination (the separation clutch is in a combination state) is changed from the rotation speed of the transmission input shaft corresponding to the actual gear to the rotation speed of the transmission input shaft corresponding to the target gear.

2) The engine starting control process in the power upshift and gear shifting process is as follows: specifically, the power smooth output of the whole vehicle is realized by specifically controlling the gear shifting clutch, the rotating speed of the high-voltage motor and the rotating speed of the engine according to the four control processes of starting the engine by the low-voltage starter selected in the starting mode, fig. 6 is a flow chart of the control process of starting the engine by the optional low-voltage starter according to the embodiment of the invention, and as shown in fig. 6, the control process can be specifically divided into four control stages, wherein the four control stages can be a pre-control process, a motor rotating speed control process, a gear shifting clutch rotating speed control process and a recovery process. FIG. 7 is a schematic representation of the speed and torque changes during an alternative power upshift startup control according to an embodiment of the present invention, as shown in FIG. 7, including four stages for the shift launch control (represented at the top of FIG. 7): a pre-control process, a motor rotating speed control process, a shifting clutch rotating speed control process and a recovery process; the starting process comprises the following steps: starting an engine, synchronizing rotating speed, combining a separating clutch and switching power source torque; on the left side of fig. 7, the states of change with respect to two references of rotational speed (e.g., the first rotational speed difference, the second rotational speed difference, and the third rotational speed difference at different stages illustrated in fig. 7, the high-voltage motor rotational speed, and the engine rotational speed), torque, and the shift clutch are illustrated; the lowermost side of fig. 7 illustrates the gear shifting process, including: oil charging of the gear shifting clutch, torque exchange of the gear shifting clutch and power source rotating speed adjustment; on the right-most side of fig. 7, shift references for various stages are shown, including: actual gear transmission input shaft speed, target gear transmission input shaft speed, disconnect clutch torque, engine torque, high-voltage motor torque, target gear shift clutch torque, and actual gear shift clutch torque.

The four control phases in fig. 6 are described below in connection with the speed and torque changes during the power upshift startup control of fig. 7:

a) the pre-control process comprises the following steps:

the engine starting is completed from the first stage of receiving the engine starting request to the starting of the engine by the low-pressure starter, and the actions of each part are as follows:

an engine: the low-pressure starter drags the engine to rotate, when the rotating speed of the engine meets the oil injection ignition condition, the engine starts oil injection ignition, and after the rotating speed is increased to be higher than the idling rotating speed, the idling running state is kept;

a motor: outputting torque according to the driving request torque;

a shifting clutch: the motor torque is used as a feedforward torque and a closed loop feedback torque of a difference value between the motor rotating speed and the target rotating speed of the motor in the pre-control process, and the rotating speed of the motor is controlled to reach the target rotating speed of the motor in the pre-control process, wherein the target rotating speed of the motor in the pre-control process can specifically refer to the rotating speed of an input shaft of a transmission corresponding to an actual gear plus a first rotating speed deviation.

The pre-control process has the following functions: the engine is started through the low-pressure starter, and because the separation clutch is in a separation state, influence factors of the starting process of the engine cannot be transmitted to the wheel end, and therefore the shifting clutch still keeps control of the original shifting process.

b) And controlling the rotating speed of the motor.

From the first stage of starting the engine by the low-pressure starter to the third stage of combining the separating clutch, the actions of each part are as follows:

an engine: the engine carries out autonomous speed regulation control to enable the rotating speed of the engine to reach the target rotating speed of the engine in the rotating speed control process of the motor;

a motor: controlling the motor rotating speed to reach the motor target rotating speed in the motor control rotating speed process by taking the driving request torque as a feedforward torque and a closed loop feedback torque of a difference value between the motor rotating speed and the motor target rotating speed in the motor control rotating speed process;

a shifting clutch: inputting open-loop control as clutch combination torque according to the driving request torque;

and in the process of controlling the rotating speed of the motor, the target rotating speed of the motor specifically refers to the rotating speed of the transmission input shaft corresponding to the actual gear plus a second rotating speed deviation, and the numerical value of the second rotating speed deviation is greater than the first rotating speed deviation.

The target rotating speed of the engine in the rotating speed control process of the motor is specifically in the second stage of engine synchronization stage (corresponding to rotating speed synchronization in fig. 7) when the low-voltage starter starts the engine, and the target rotating speed of the engine in the rotating speed control process of the motor is equal to the rotating speed of the motor plus a third rotating speed deviation; in the clutch separating and combining stage of the third stage of starting the engine by the low-voltage starter, the target rotating speed of the engine is equal to the target rotating speed of the motor in the rotating speed controlling process of the motor.

The motor control rotating speed process has the following functions: the engine speed synchronization and clutch combination process is to connect the engine as the power input source into the power transmission system, in order to avoid the influence on the wheel end of the vehicle, the torque transmission direction is ensured by the target speed control mode of the engine speed, the motor speed and the transmission input shaft speed, and the torque of the gear shifting clutch is ensured to be stable only by the open loop control mode of taking the driving request torque as the input, thereby ensuring the smoothness of the vehicle.

c) The process of controlling the rotating speed of the gear shifting clutch is as follows:

from the completion of the combination of the separating clutch at the third stage of starting the engine by the low-pressure starter to the completion of the torque switching of the power source at the fourth stage, the actions of all the components are as follows:

an engine: the engine torque increases to the driving request torque at the maximum rate achievable;

a motor: the motor torque is equal to the driving request torque minus the engine torque;

a shifting clutch: the motor speed is controlled to reach the motor target speed in the speed control process of the gear shifting clutch by taking the driving request torque as a feed-forward torque and a closed loop feedback torque of a difference value of the motor speed and the motor target speed in the speed control process of the gear shifting clutch. The method comprises the following steps that a gear shifting clutch controls the target rotating speed of a motor in the rotating speed process, and specifically, before the rotating speed regulating process of a power source in the third stage of power upshift begins, the rotating speed of an input shaft of a transmission corresponding to an actual gear is added with a second rotating speed deviation; after the power source rotating speed regulating process is finished in the third stage of power upshift, the rotating speed of the transmission input shaft corresponding to the target gear is added with a second rotating speed deviation; in the process of regulating the rotating speed of the power source in the third stage of power upshift; and adding a second rotating speed deviation to the rotating speed of the transmission input shaft corresponding to the actual gear and the rotating speed of the transmission input shaft corresponding to the target gear according to a preset transition curve.

d) And (3) recovery process: and (3) from the completion of the torque switching of the fourth section of power source to the restoration of the target rotating speed of the motor to the normal state, the actions of all the parts are as follows:

an engine: the engine torque requests output torque according to a hybrid strategy;

a motor: the motor torque requests to output torque according to a hybrid strategy;

a shifting clutch: the method comprises the steps of controlling the rotating speed of a motor to reach a target rotating speed of the motor in a recovery process by using a driving request torque as a feedforward torque and a closed-loop feedback torque of a difference value of the target rotating speed of the motor in the recovery process, wherein the target rotating speed of the motor in the recovery process is specifically the rotating speed of an input shaft of a target transmission plus a first rotating speed deviation in a speed regulation stage corresponding to a target gear.

And 4.2, controlling the power downshift starting machine.

1) And (5) a power downshift gear shifting process. FIG. 8 is a schematic diagram of an alternative power downshift and coast upshift process according to an embodiment of the present invention, as shown in FIG. 8, the power downshift process being divided into two steps:

a) and (3) power source rotating speed regulation: the rotating speed of the motor (the separation clutch is in a separation state) or the rotating speed of the motor and engine combination body (the separation clutch is in a combination state) is changed from the rotating speed of the transmission input shaft corresponding to the actual gear to the rotating speed of the transmission input shaft corresponding to the target gear; meanwhile, the gear shifting clutch of the target gear is filled with oil to prepare for the torque switching of the clutch at the next stage;

b) shifting clutch torque switching: the torque transmission of the transmission is switched from the gear shifting clutch of the actual gear to the target gear clutch, so that the speed ratio is switched.

2) The engine start control process in the power downshift gear shifting process is the same as the engine start process in the power upshift gear shifting process, and the control content of each process is also the same, which is not described herein again.

4.3, controlling the sliding up-shift starting.

1) And (5) a sliding upshift gear shifting process.

FIG. 8 is a schematic diagram of an alternative power downshift and coast upshift process in which the coast upshift is initiated in two steps, as shown in FIG. 8, according to an embodiment of the present invention:

a) and (3) power source rotating speed regulation: the rotating speed of the motor (the separation clutch is in a separation state) or the rotating speed of the motor and engine assembly (the separation clutch is in a combination state) is changed from the rotating speed of the transmission input shaft corresponding to the actual gear to the rotating speed of the transmission input shaft corresponding to the target gear; meanwhile, the gear shifting clutch of the target gear is filled with oil to prepare for the torque switching of the clutch at the next stage;

2) And starting the engine in the process of sliding up-shifting and shifting gears.

The engine starting control process in the coasting upshift and gear shifting process is the same as that in the power upshift and gear shifting process, but the calculation of the target rotating speed in the control content is different, and the difference details are as follows:

a) the difference of the pre-control process is as follows:

in the engine starting control process in the sliding gear-up and gear-shifting process, the target rotating speed of a motor in the process is pre-controlled, specifically, the target rotating speed is obtained by subtracting a first rotating speed deviation from the rotating speed of an input shaft of a transmission corresponding to an actual gear.

b) The difference of the motor speed control process is as follows:

in the engine starting control process in the sliding gear-up and gear-shifting process, the target rotating speed of the motor is controlled by the motor in the rotating speed control process, specifically, the target rotating speed is obtained by subtracting a second rotating speed deviation from the rotating speed of the transmission input shaft corresponding to the actual gear.

c) The difference of the speed control process of the gear shifting clutch is as follows:

in the engine starting control process in the sliding gear-up and gear-shifting process, the gear-shifting clutch controls the target rotating speed of the motor in the rotating speed process, and specifically, before the rotating speed regulating process of the power source in the third stage of power gear-up, the rotating speed of the transmission input shaft corresponding to the actual gear is subtracted by the second rotating speed deviation; after the power source rotating speed regulating process in the third power gear-up stage is finished, subtracting a second rotating speed deviation from the rotating speed of the transmission input shaft corresponding to the target gear; during the speed regulation process of the rotating speed of the power source in the third stage of power upshift; and subtracting the second rotating speed deviation from the rotating speed of the transmission input shaft corresponding to the actual gear and the rotating speed of the transmission input shaft corresponding to the target gear according to a preset transition curve.

d) The difference in the recovery process is:

and in the engine starting control process in the sliding gear-up and gear-shifting process, restoring the process motor target rotating speed, specifically, subtracting the first rotating speed deviation from the rotating speed of the transmission input shaft corresponding to the target gear.

4.3, controlling the sliding gear-down starting machine.

1) And (5) a sliding downshift gear shifting process. Fig. 9 is a schematic diagram of an alternative coast downshift procedure according to an embodiment of the invention, in which the coast downshift start-up control, the coast downshift procedure is divided into three steps, as shown in fig. 9:

The engine start control process in the sliding downshift gear shifting process is the same as the engine start control process in the sliding upshift gear shifting process, and the control content of each process is also the same, which is not described herein again.

The embodiment provides a method for controlling the starting of an engine in the process of vehicle gear shifting. When an engine starting request occurs in the gear shifting process, firstly, a proper starting mode is selected, secondly, the engine speed, the motor speed and the transmission input shaft speed are taken as control targets, different control strategies are formulated according to different gear shifting types, and coordinated control of engine starting in the gear shifting process is realized. The smoothness of the whole vehicle when the engine is started in the gear shifting process is improved, and the dynamic comfort of the whole vehicle is further improved.

The invention is described below in connection with an alternative embodiment.

EXAMPLE III

The present embodiment provides an alternative vehicle shifting apparatus, which includes various implementation units corresponding to the implementation steps in the above embodiments.

The vehicle shifting device according to the embodiment of the present invention may be used to execute the vehicle shifting method according to the embodiment of the present invention, and the vehicle shifting device according to the embodiment of the present invention is described below.

Fig. 10 is a schematic diagram of an alternative vehicle shifting apparatus according to an embodiment of the present invention, as shown in fig. 10, including: a selection unit 111, a processing unit 112, a first determination unit 113, a control unit 114, wherein,

the selecting unit 111 is used for selecting a target starting strategy under the condition that the current vehicle enters a starting mode in gear shifting;

the processing unit 112 is configured to start the current vehicle by using a target start strategy, and acquire a high-voltage motor state, an actual operating gear, and a target gear of the current vehicle;

a first determination unit 113 for determining a target shift type based on a current high voltage motor state of the vehicle, an actual operating gear, and a target gear;

and a control unit 114 for controlling the current vehicle to realize the engine start during the gear shifting process by adopting the target gear shifting type.

According to the gear shifting device of the vehicle, a target starting strategy is selected through the selection unit 111 under the condition that the current vehicle enters a starting mode in gear shifting, then the current vehicle is started through the processing unit 112 by adopting the target starting strategy, the high-voltage motor state, the actual operating gear and the target gear of the current vehicle are obtained, then a target gear shifting type is determined through the first determination unit 113 based on the high-voltage motor state, the actual operating gear and the target gear of the current vehicle, and finally the target gear shifting type is adopted through the control unit 114 to control the current vehicle to realize engine starting in the gear shifting process. In the embodiment, the starting strategy is selected firstly, then the gear shifting type is determined according to the state of the vehicle and the target gear requirement, and the engine is controlled to start according to the gear shifting type, so that the purpose of coordinated gear shifting and engine starting coordinated control is achieved, the technical effects of improving the smoothness, comfort and safety of the vehicle in the gear shifting process of the vehicle are achieved, and the technical problems of low smoothness and poor safety of vehicle driving caused by the fact that the gear shifting and the engine starting cannot be coordinated and controlled in the gear shifting process of the vehicle in the related technology are solved.

Optionally, the vehicle shifting device further includes an obtaining unit, configured to obtain an engine start-stop condition of the current vehicle before the current vehicle enters the shift start mode; the first judgment unit is used for judging whether the engine is started or not based on the engine starting and stopping conditions; the second judgment unit is used for judging whether the actual operation gear of the transmission is consistent with the target gear or not under the condition that the engine is determined to be started under the engine starting and stopping conditions; and the second determination unit is used for determining to enter the starting mode in gear shifting under the condition that the actual operation gear and the target gear of the transmission are inconsistent.

Optionally, the processing unit includes: the first processing subunit is used for dragging the engine to rotate by adopting the low-pressure starter, starting oil injection ignition of the engine when the rotating speed of the engine meets an oil injection ignition condition, controlling the rotating speed of the engine to rush to an idle rotating speed and keeping an idle running state; the first control subunit is used for controlling the speed of the engine to be regulated to a target rotating speed and controlling the separation clutch to start oil charging; and the second control subunit is used for controlling the separation clutch to start to be combined after the rotating speed of the engine reaches the target rotating speed so as to synchronize the rotating speed of the engine and the rotating speed of the high-voltage motor.

Optionally, the first determining unit includes: the first determining subunit is used for determining that the target gear shifting type is a power upshift starting machine under the condition that the state of the high-voltage motor indicates that the torque of the high-voltage motor is greater than a first torque threshold value and the target gear is greater than an actual operating gear; the second determining subunit is used for determining that the target gear shifting type is a power downshift starting machine under the condition that the state of the high-voltage motor indicates that the torque of the high-voltage motor is greater than the first torque threshold and the target gear is smaller than the actual operating gear; the third determining subunit is used for determining that the target gear shifting type is a sliding upshift starting machine under the condition that the high-voltage motor state indicates that the torque of the high-voltage motor is smaller than the first torque threshold value and the target gear is larger than the actual operating gear; and the fourth determining subunit is used for determining that the target gear shifting type is the coasting downshift starting machine under the condition that the state of the high-voltage motor indicates that the torque of the high-voltage motor is smaller than the first torque threshold and the target gear is smaller than the actual operating gear.

Optionally, the control unit further includes: the third control subunit is used for controlling the oil filling of the shifting clutch under the target gear under the condition that the target gear shifting type is the power upshift starting machine or the coasting downshift starting machine; a fourth control subunit that controls torque transmission of the transmission to be switched from the shift clutch of the actual operating gear to the shift clutch of the target gear; the fifth control subunit is used for controlling the rotating speed of the motor, or controlling the rotating speed of the motor and engine combination to change from the rotating speed of the transmission input shaft corresponding to the actual operating gear to the rotating speed of the transmission input shaft corresponding to the target gear; the fifth determining subunit is used for determining that the current vehicle completes power upshift gear shifting operation or coasting downshift gear shifting operation when the rotating speed of the transmission input shaft corresponding to the target gear is reached; and the sixth control subunit is used for controlling the engine to smoothly start in the process that the current vehicle completes the power upshift gear shifting operation or the sliding downshift gear shifting operation.

Optionally, the second control module includes: the first processing submodule is used for controlling the low-pressure starter to start the engine to enter a second-stage engine synchronization stage after controlling the low-pressure starter to finish starting the engine in a first stage, and the target rotating speed of the engine is equal to the sum of the rotating speed of the motor and a preset rotating speed deviation; and the second processing submodule is used for controlling the target rotating speed of the engine to reach the target rotating speed of the motor in the rotating speed control process when the low-voltage starter starts the engine and enters a separating clutch combination stage of a third stage, and the engine is used as a power input source and is connected to the power transmission system.

Optionally, the third control module includes: a first control submodule for controlling the engine torque to increase to the driving request torque at a maximum rate after the clutch-off engagement of the third stage is completed; and the determining submodule is used for determining the closed-loop feedback torque based on the driving request torque and the motor target rotating speed in the rotating speed control process of the gear shifting clutch, and controlling the rotating speed of the motor to reach the motor target rotating speed in the rotating speed control process of the gear shifting clutch by combining the closed-loop feedback torque.

Optionally, the control unit further includes: the seventh control subunit is used for controlling the rotating speed of the motor or the rotating speed of a combination of the motor and the engine under the condition that the target gear shifting type is power downshift starting or coast upshift starting, changing the rotating speed of the transmission input shaft corresponding to the actual operating gear to the rotating speed of the transmission input shaft corresponding to the target gear, and controlling the oil charging of the gear shifting clutch of the target gear; and the eighth control subunit is used for controlling the torque transmission of the transmission to be switched from the gear shifting clutch of the actual running gear to the target gear clutch, so that the current vehicle finishes the power downshift gear shifting operation or the sliding upshift gear shifting operation, and further the engine is controlled to be smoothly started.

The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments.

In the above embodiments of the present invention, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments.

In the embodiments provided in the present application, it should be understood that the disclosed technology can be implemented in other ways. The above-described apparatus embodiments are merely illustrative, and for example, a division of a unit may be a logical division, and in actual implementation, there may be another division, for example, multiple units or components may be combined or may be integrated into another system, or some features may be omitted, or may not be executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, units or modules, and may be in an electrical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a removable hard disk, a magnetic disk, or an optical disk, and various media capable of storing program codes.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that it is obvious to those skilled in the art that various modifications and improvements can be made without departing from the principle of the present invention, and these modifications and improvements should also be considered as the protection scope of the present invention.

Claims

1. A shifting method of a vehicle, characterized by comprising:

selecting a target starting strategy under the condition that the current vehicle enters a starting mode in gear shifting;

starting the current vehicle by adopting the target starting strategy, and acquiring the high-voltage motor state, the actual operation gear and the target gear of the current vehicle;

determining a target gear shifting type based on the high-voltage motor state, the actual operation gear and the target gear of the current vehicle;

and controlling the current vehicle to realize the starting of the engine in the gear shifting process by adopting the target gear shifting type.

2. The gear shifting method of claim 1, further comprising, before the current vehicle enters a gear shift start mode:

acquiring the engine starting and stopping conditions of the current vehicle;

judging whether to start the engine or not based on the engine starting and stopping conditions;

judging whether the actual operation gear of the transmission is consistent with the target gear or not under the condition that the engine is determined to be started under the engine starting and stopping conditions;

and determining to enter the start-in-shift mode in the case that the actual operation gear and the target gear of the transmission are inconsistent.

3. The gear shifting method of claim 1, wherein the step of activating the current vehicle using the target start-up strategy comprises:

the low-pressure starter is adopted to drag the engine to rotate, when the rotating speed of the engine meets the oil injection ignition condition, the engine starts oil injection ignition, the rotating speed of the engine is controlled to be rushed up to the idling rotating speed, and the idling running state is kept;

controlling the engine to regulate the speed to a target rotating speed, and simultaneously controlling the separation clutch to start oil filling;

and after the rotating speed of the engine reaches the target rotating speed, controlling a separating clutch to start to be combined so as to synchronize the rotating speed of the engine and the rotating speed of the high-voltage motor.

4. The gear shifting method of claim 1, wherein the step of determining a target gear shift type based on the current vehicle high voltage machine state, actual operating gear, and target gear comprises:

determining that the target gear shifting type is a power upshift starting machine under the condition that the high-voltage motor state indicates that the torque of the high-voltage motor is greater than a first torque threshold value and the target gear is greater than the actual operating gear;

determining that the target gear shifting type is a power downshift starting machine under the condition that the high-voltage motor state indicates that the torque of the high-voltage motor is larger than a first torque threshold value and the target gear is smaller than the actual operating gear;

determining that the target gear shifting type is a sliding upshift starting machine under the condition that the high-voltage motor state indicates that the torque of the high-voltage motor is smaller than a first torque threshold value and the target gear is larger than the actual running gear;

and determining that the target gear shifting type is a coasting and downshift starting machine under the condition that the high-voltage motor state indicates that the torque of the high-voltage motor is smaller than a first torque threshold value and the target gear is smaller than the actual running gear.

5. The method of shifting of claim 4, wherein the step of controlling the current vehicle to effect an engine start during a shift using the target shift type if the target shift type is a power upshift initiate or a coast downshift initiate includes:

controlling a shifting clutch under the target gear to fill oil;

controlling torque transmission of the transmission to shift from the shift clutch of the actual operating gear to the shift clutch of the target gear;

controlling the rotating speed of the motor, or controlling the rotating speed of a combination of the motor and the engine, and changing from the rotating speed of the transmission input shaft corresponding to the actual operating gear to the rotating speed of the transmission input shaft corresponding to the target gear;

determining that the current vehicle completes power upshift gear shifting operation or coasting downshift gear shifting operation under the condition that the rotating speed of the transmission input shaft corresponding to the target gear is reached;

and controlling the engine to smoothly start in the process of finishing the power upshift gear shifting operation or the sliding downshift gear shifting operation of the current vehicle.

6. The method of shifting of claim 5, wherein the step of controlling the engine to start smoothly during the current vehicle power upshift shift operation comprises:

under the condition of receiving an engine starting request, controlling a low-pressure starter to start the engine to finish the first-stage engine starting, wherein in the process of controlling the low-pressure starter to start the engine, the rotating speed of the motor is controlled to reach a target rotating speed by using the closed-loop feedback torque of the motor;

controlling the low-pressure starter, and completing the combination of the separating clutch from the engine starting of the first stage to the third stage;

controlling a low-pressure starter, and completing power source torque switching from a third-stage separation clutch combination to a fourth stage, wherein after the third-stage separation clutch combination is completed, acquiring the rotation speed of a transmission input shaft corresponding to an actual operation gear plus a second rotation speed deviation, acquiring the rotation speed of the transmission input shaft corresponding to a target gear plus the second rotation speed deviation, and acquiring the rotation speed of the transmission input shaft corresponding to the actual operation gear and the rotation speed of the transmission input shaft corresponding to the target gear according to a preset transition curve plus the second rotation speed deviation;

and controlling the current vehicle to be completed by switching the torque of the power source in the fourth stage until the target rotating speed of the motor is recovered to a normal state so as to enable the engine to be started smoothly, wherein in the process of recovering to the normal state, the rotating speed of the transmission input shaft corresponding to the target gear is controlled to be added with the first rotating speed deviation.

7. The method of shifting of claim 6, wherein the step of controlling the low-pressure starter to complete the off-clutch engagement from the first phase of engine cranking to the third phase comprises:

after the low-pressure starter is controlled to finish the starting of the engine in the first stage, the low-pressure starter is controlled to start the engine to enter the engine synchronization stage in the second stage, and the target rotating speed of the engine is equal to the sum of the rotating speed of the motor and the preset rotating speed deviation;

and controlling the target rotating speed of the engine to reach the target rotating speed of the motor in the rotating speed control process when the low-pressure starter starts the engine and enters a separating clutch combination stage of a third stage, and connecting the engine serving as a power input source into a power transmission system.

8. The method of shifting of claim 6, wherein the step of controlling the low-pressure starter to effect the power source torque transition from the third phase of disengagement of the clutch to the fourth phase comprises:

controlling the engine torque to increase at a maximum rate to the driving request torque after controlling the low-pressure starter to start the engine in a third stage of engaging the disconnect clutch;

and determining a closed-loop feedback torque based on the driving request torque and the target rotating speed of the motor in the rotating speed control process of the gear shifting clutch, and controlling the rotating speed of the motor to reach the target rotating speed of the motor in the rotating speed control process of the gear shifting clutch by combining the closed-loop feedback torque.

9. The method of shifting of claim 4, wherein the step of controlling the current vehicle to effect engine start during a shift using the target shift type if the target shift type is a power downshift initiate or a coast upshift initiate, comprises:

controlling the rotating speed of a motor or the rotating speed of a combination of the motor and the engine, changing from the rotating speed of an input shaft of a transmission corresponding to an actual operating gear to the rotating speed of the input shaft of the transmission corresponding to the target gear, and controlling the oil charge of a shifting clutch of the target gear;

and controlling the torque transmission of the transmission to be switched from the gear shifting clutch of the actual running gear to the target gear clutch, so that the current vehicle finishes the power downshift gear shifting operation or the sliding upshift gear shifting operation, and further controlling the engine to smoothly start.

10. A shifting apparatus for a vehicle, characterized by comprising:

the selection unit is used for selecting a target starting strategy under the condition that the current vehicle enters a starting mode in gear shifting;

the processing unit is used for starting the current vehicle by adopting the target starting strategy and acquiring the high-voltage motor state, the actual running gear and the target gear of the current vehicle;

the first determination unit is used for determining a target gear shifting type based on the high-voltage motor state, the actual operation gear and the target gear of the current vehicle;

and the control unit is used for controlling the current vehicle to realize the engine starting in the gear shifting process by adopting the target gear shifting type.