A control method and device for a dual-clutch transmission

Abstract

This invention provides a control method and apparatus for a dual-clutch transmission. During vehicle coasting, it detects in real-time whether there is a need for braking downshifting. If a braking downshifting need is detected, it determines whether the need is for multiple gear downshifts. If it is, it collects current operating condition information and, based on this information and the target gear, controls the torque of the target clutch in the dual-clutch transmission to maintain the target torque until the vehicle downshifts from the current gear to the target gear. If the need is for a single gear downshift, it uses a coasting-without-throttle downshifting method to downshift from the current gear to the target gear. Based on this invention, it not only solves the problems of jerking caused by untimely downshifting and frequent clutch interaction when braking hard during coasting, but also addresses the issue of weak throttle response after braking during coasting.

Description

Technical Field

[0001] This invention relates to the field of engine technology, and more specifically, to a control method and apparatus for a dual-clutch transmission. Background Technology

[0002] A DCT (Dual Clutch Transmission) is an automatic transmission based on a manual transmission (MT) that uses a TCU (Transmission Control Unit) and valve body to replace the manual shift lever. To ensure uninterrupted power transmission, it employs two clutches to control power delivery. During vehicle operation, we often encounter unexpected situations requiring emergency braking to avoid danger. For example, when a driver rapidly applies the brakes during smooth driving, how to ensure a smooth and seamless vehicle response during this process, and how to guarantee a rapid and responsive acceleration after braking, are the key research focuses of this technology.

[0003] When the driver applies the brakes hard at a relatively fast rate during smooth driving, the dual-clutch automatic transmission will downshift to obtain greater braking force. When the brakes are applied hard, the vehicle speed drops rapidly. If sequential downshifting is used at this time, it will result in untimely downshifting, which may lead to problems such as low speed and high gear, and stalling. On the other hand, the frequent and rapid action of the dual-clutch transmission can easily cause performance problems such as jerking. Summary of the Invention

[0004] In view of this, the present invention provides a control method and device for a dual-clutch transmission to solve problems such as delayed downshifting during coasting braking when the brake is pressed hard or the accelerator is pressed after braking, resulting in stalling at low speeds in high gears, frequent clutch interaction, jerking noise, and weak accelerator power.

[0005] The first aspect of this invention discloses a control method for a dual-clutch transmission, the method comprising:

[0006] During vehicle coasting, the system continuously monitors whether the vehicle requires braking and downshifting.

[0007] If a braking downshifting requirement is detected in the vehicle, it is determined whether the braking downshifting requirement is a multi-gear downshifting requirement, wherein the braking downshifting requirement carries a target gear.

[0008] If the braking downshift requirement is a multi-gear downshift requirement, the current operating condition information is collected, and based on the current operating condition information and the target gear, the torque of the target clutch in the dual-clutch transmission of the vehicle is controlled to remain at the target torque until the vehicle downshifts from the current gear to the target gear. Here, the target torque is the torque corresponding to the gear indicated by the braking downshift requirement, and the target clutch is the clutch in the dual-clutch transmission of the vehicle corresponding to the current gear of the vehicle.

[0009] If the braking downshift requirement is a single-gear downshift requirement, the vehicle is downshifted from the current gear to the target gear by coasting downshifting without throttle.

[0010] Optionally, after the vehicle downshifts from the current gear to the target gear, the method further includes:

[0011] When the downshifting demand of the vehicle is detected to change from a braking downshifting demand to a braking release downshifting demand, a single-clutch control and EMS coordination request method is used to control the vehicle to downshift from the target gear to the gear indicated by the braking release downshifting demand.

[0012] Optionally, the method further includes:

[0013] During the downshifting process, if the current vehicle speed is detected to be greater than a preset speed threshold and the driver presses the accelerator pedal, torque is transmitted through the current offgoing clutch in the dual-clutch transmission of the vehicle to control the vehicle to downshift from the current gear to the target gear.

[0014] Optionally, the method further includes:

[0015] During the downshifting process, if the current vehicle speed is detected to be lower than a preset speed threshold, and the driver presses the accelerator pedal, the engine speed is increased to a preset speed, and then the current gear of the vehicle is switched to the gear corresponding to the preset speed.

[0016] Optionally, the method further includes:

[0017] Once the vehicle has completed a gear shift, the clutch in the vehicle's dual-clutch transmission corresponding to the current gear position controls the vehicle's stable driving.

[0018] A second aspect of the present invention discloses a control device for a dual-clutch transmission, the device comprising:

[0019] The real-time detection unit is used to detect in real time whether the vehicle needs to brake and downshift during the vehicle's coasting process;

[0020] The determination unit is used to determine whether the braking downshifting demand is a multi-gear downshifting demand if the vehicle is detected to have a braking downshifting demand, wherein the braking downshifting demand carries a target gear.

[0021] The first downshift unit is used to collect current operating condition information if the braking downshift requirement is a multi-gear downshift requirement, and control the torque of the target clutch in the dual-clutch transmission of the vehicle to be maintained at the target torque according to the current operating condition information and the target gear, until the vehicle downshifts from the current gear to the target gear. The target torque is the torque corresponding to the gear indicated by the braking downshift requirement, and the target clutch is the clutch in the dual-clutch transmission of the vehicle corresponding to the current gear of the vehicle.

[0022] The second downshift unit is used to downshift the vehicle from the current gear to the target gear by coasting downshifting without throttle if the braking downshifting requirement is a single-gear braking downshifting requirement.

[0023] Optionally, the device includes:

[0024] The third downshift unit is used to control the vehicle to downshift from the target gear to the gear indicated by the brake release downshift requirement when the downshift requirement of the vehicle is detected to change from a brake release downshift requirement. This is achieved by using a single-clutch control and requesting EMS coordination.

[0025] Optionally, the device includes:

[0026] The transmission unit is used to transmit torque through the current offgoing clutch in the dual-clutch transmission of the vehicle during the downshifting process if the current vehicle speed is detected to be greater than a preset vehicle speed threshold and the driver presses the accelerator pedal, so as to control the vehicle to downshift from the current gear to the target gear.

[0027] Optionally, the device includes:

[0028] The gear shifting unit is used to, during the downshifting process of the vehicle, if it detects that the current vehicle speed is less than a preset vehicle speed threshold and the driver presses the accelerator pedal, increase the engine speed to a preset speed and then shift the current gear of the vehicle to the gear corresponding to the preset speed.

[0029] Optionally, the device includes:

[0030] The control unit is used to control the vehicle to drive stably by means of the clutch in the dual-clutch transmission corresponding to the current gear of the vehicle when the vehicle has completed a gear shift.

[0031] This invention provides a control method and apparatus for a dual-clutch transmission. During vehicle coasting, the method detects in real time whether there is a braking downshift requirement. When a braking downshift requirement is detected, it determines whether the detected braking downshift requirement is a multi-gear downshift requirement. If it is determined that the detected braking downshift requirement is a multi-gear downshift requirement, the method collects current operating condition information. Based on the collected current operating condition information and the target gear indicated by the braking downshift requirement, the method controls the torque of the target clutch in the dual-clutch transmission corresponding to the vehicle's current gear to maintain the target torque until the vehicle's current gear is downshifted to the target gear. If it is determined that the braking downshift requirement is not a multi-gear downshift requirement, but a single-gear downshift requirement, the method uses coasting downshifting without throttle to downshift the vehicle's current gear to the gear indicated by the braking downshift requirement. The technical solution provided by this invention addresses the issue of rapid downshifting when a vehicle needs to downshift during braking. It controls the torque of the target clutch in the dual-clutch transmission corresponding to the vehicle's current gear to maintain the target torque based on current operating conditions and the target gear required for downshifting. This process continues until the vehicle's current gear is downshifted to the target gear, achieving rapid downshifting. This solves problems such as delayed downshifting during coasting braking, leading to stalling at low speeds in high gears, frequent clutch engagement, jerking noise, and weak accelerator power. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0033] Figure 1 A flowchart illustrating a control method for a dual-clutch transmission provided in an embodiment of the present invention;

[0034] Figure 2 A flowchart illustrating another control method for a dual-clutch transmission provided in an embodiment of the present invention;

[0035] Figure 3 A flowchart illustrating another control method for a dual-clutch transmission provided in an embodiment of the present invention;

[0036] Figure 4 A flowchart illustrating another control method for a dual-clutch transmission provided in an embodiment of the present invention;

[0037] Figure 5 This is a schematic diagram of the structure of a control device for a dual-clutch transmission provided in an embodiment of the present invention. Detailed Implementation

[0038] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0039] The term "comprising" and its variations as used herein are open-ended inclusions, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Definitions of other terms will be given in the description below.

[0040] It should be noted that the concepts of "first" and "second" mentioned in this invention are only used to distinguish different devices, modules or units, and are not used to limit the order of functions performed by these devices, modules or units or their interdependencies.

[0041] It should be noted that the terms "a" and "a plurality of" used in this invention disclosure are illustrative rather than restrictive. Those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0042] See Figure 1 The diagram illustrates a flow chart of a control method for a dual-clutch transmission provided by an embodiment of the present invention. The control method specifically includes the following steps:

[0043] S101: During vehicle coasting, detect in real time whether the vehicle needs to brake and downshift; if the vehicle needs to brake and downshift, execute step S102.

[0044] During the execution of step S101, while the vehicle is coasting, it is possible to detect in real time whether the vehicle has a need for braking downshifting. If a need for braking downshifting is detected, step S102 is executed; if no need for braking downshifting is detected, the vehicle is monitored until a need for braking downshifting is detected, at which point step S102 is executed.

[0045] S102: Determine whether the braking downshift demand is a multi-gear downshift demand; if the braking downshift demand is a multi-gear downshift demand, proceed to step S103; if the braking downshift demand is a single-gear downshift demand, proceed to step S104.

[0046] Among them, the braking downshift requirement includes the target gear.

[0047] During the specific execution of step S102, if a braking downshifting requirement is detected, it is further determined whether the detected braking downshifting requirement is a multi-gear downshifting requirement. If the detected braking downshifting requirement is a multi-gear downshifting requirement, step S103 is executed; if the detected braking downshifting requirement is not a multi-gear downshifting requirement, it can be determined that the braking downshifting requirement is a single-gear downshifting requirement, and step S104 is executed.

[0048] It should be noted that a single-gear downshift requirement refers to a downshift requirement indicating that the vehicle needs to downshift to a gear one gear lower than its current gear; a multi-gear downshift requirement refers to a downshift requirement indicating that the vehicle needs to downshift to a gear two or more gears lower than its current gear.

[0049] For example, if the vehicle is currently in 7th gear, and the target gear for the detected braking downshift demand is 4th gear, it can be determined that the detected braking downshift demand is a multi-gear downshift demand; if the target gear for the detected braking downshift demand is 6th gear, it can be determined that the detected braking downshift demand is a single-gear downshift demand.

[0050] S103: Collects current operating condition information and, based on the current operating condition information and the target gear, controls the torque of the target clutch in the vehicle's dual-clutch transmission to maintain the target torque until the vehicle's current gear drops to the target gear.

[0051] During the specific execution of step S103, if it is determined that the detected braking downshifting demand is a braking downshifting demand, the current operating condition information of the vehicle can be collected; wherein, the current operating condition information of the vehicle includes at least the current gear of the vehicle.

[0052] Based on the collected current operating condition information and target gear, the torque of the target clutch in the vehicle's dual-clutch transmission is maintained at the target torque until the vehicle's current gear shifts down to the target gear. Here, the target torque is the torque corresponding to the gear indicated by the braking downshift demand, and the target clutch is the clutch in the vehicle's dual-clutch transmission corresponding to the vehicle's current gear.

[0053] It should be noted that if the vehicle is currently in 7th gear, the target clutch is the odd clutch in the vehicle's dual-clutch transmission; if the vehicle is currently in 6th gear, the target clutch is the even clutch in the vehicle's dual-clutch transmission.

[0054] It should be noted that when the vehicle's current gear is downshifted to the target gear, the shift fork corresponding to the target gear is engaged. At this time, the torque of the clutch in the vehicle's dual-clutch transmission corresponding to the target gear will also remain at the target torque. In other words, when the vehicle's current gear is downshifted to the target gear, the torque of both the odd and even clutches in the vehicle's dual-clutch transmission will remain at the target torque.

[0055] For example, if the target gear for braking downshifting is 4th gear, and the vehicle's current gear is 7th gear, then the braking downshifting requirement can be determined to be a multi-gear downshifting requirement. The vehicle's current operating condition information is then collected. Based on the collected current operating condition information and the target gear, the torque of the odd clutch in the vehicle's dual-clutch transmission corresponding to the vehicle's current gear (7th gear) is maintained at the target torque until the vehicle's current gear drops to the target gear. When the vehicle's current gear drops to the target gear, the shift fork corresponding to the target gear (4th gear) will switch from unengaged to engaged. At this time, the torque of the even clutch in the vehicle's dual-clutch transmission will also maintain the target torque. That is, when the vehicle's current gear drops to the target gear, both the odd and even clutches in the vehicle's dual-clutch transmission will maintain the target torque.

[0056] Furthermore, in this embodiment, when the vehicle is downshifted from the current gear to the target gear, if the brake is applied, the vehicle speed will continue to decrease. When the vehicle speed drops to 0, the shift fork state corresponding to the 1st gear is switched to engaged, and the clutch in the dual-clutch controller of the vehicle is kept near the KissPoint.

[0057] S104: Use coasting downshifting without throttle to downshift the vehicle's current gear to the gear indicated by the braking downshift requirement.

[0058] In the specific execution of step S104, if it is determined that the detected braking downshifting demand is a single-gear braking downshifting demand, the current gear of the vehicle is downshifted to the gear indicated by the braking downshifting demand by using a coasting downshifting method without throttle.

[0059] This invention provides a control method for a dual-clutch transmission. During vehicle coasting, the method detects in real time whether there is a braking downshift requirement. When a braking downshift requirement is detected, it determines whether the detected braking downshift requirement is a multi-gear downshift requirement. If the detected braking downshift requirement is determined to be a multi-gear downshift requirement, current operating condition information is collected. Based on the collected current operating condition information and the target gear indicated by the braking downshift requirement, the torque of the target clutch in the dual-clutch transmission corresponding to the vehicle's current gear is maintained at the target torque until the vehicle's current gear is downshifted to the target gear. If the braking downshift requirement is determined to be a single-gear downshift requirement rather than a multi-gear downshift requirement, a coasting downshift without throttle is used to downshift the vehicle's current gear to the gear indicated by the braking downshift requirement. The technical solution provided by this invention addresses the issue of rapid downshifting when a vehicle needs to downshift during braking. It controls the torque of the target clutch in the dual-clutch transmission corresponding to the vehicle's current gear to maintain the target torque based on current operating conditions and the target gear required for downshifting. This process continues until the vehicle's current gear is downshifted to the target gear, achieving rapid downshifting. This solves problems such as delayed downshifting during coasting braking, leading to stalling at low speeds in high gears, frequent clutch engagement, jerking noise, and weak accelerator power.

[0060] See Figure 2 The diagram illustrates a flowchart of another control method for a dual-clutch transmission provided by an embodiment of the present invention. This control method specifically includes the following steps:

[0061] S201: During vehicle coasting, detect in real time whether the vehicle needs to brake and downshift; if the vehicle needs to brake and downshift, execute step S202.

[0062] S202: Determine whether the braking downshift demand is a multi-gear downshift demand; if the braking downshift demand is a multi-gear downshift demand, proceed to step S203; if the braking downshift demand is a single-gear downshift demand, proceed to step S204.

[0063] Among them, the braking downshift requirement includes the target gear.

[0064] S203: Collects current operating condition information and, based on the current operating condition information and the target gear, controls the torque of the target clutch in the vehicle's dual-clutch transmission to maintain the target torque until the vehicle's current gear drops to the target gear.

[0065] The target torque is the torque corresponding to the gear indicated by the braking downshift requirement, and the target clutch is the clutch corresponding to the current gear in the vehicle's dual-clutch transmission.

[0066] S204: Use coasting downshifting without throttle to downshift the vehicle's current gear to the gear indicated by the braking downshift requirement.

[0067] In the specific execution of steps S201 to S204, the specific execution process and implementation principle of steps S201 to S204 are the same as those disclosed in the above embodiments of the present invention. Figure 1 The specific execution process and implementation principle of steps S101 to S104 are the same, and can be found in the above-described embodiments of the present invention. Figure 1 The relevant parts are not elaborated here.

[0068] S205: When the downshifting demand of the vehicle is detected to change from braking downshifting demand to releasing braking downshifting demand, the vehicle is controlled to downshift from the target gear to the gear indicated by the releasing braking downshifting demand by using a single clutch control and requesting EMS coordination.

[0069] In the specific execution of step S205, after the vehicle downshifts from the current gear to the target gear indicated by the braking downshift demand, when it is detected that the downshift demand of the vehicle has changed from braking demand to braking release downshift demand, a single-clutch control and EMS coordination method is used to control the vehicle to downshift from the target gear to the gear indicated by the braking release downshift demand.

[0070] Specifically, the engine sends the speed corresponding to the gear indicated by the brake release downshift requirement to the engine control system (EMS). Using the clutch in the vehicle's dual-clutch transmission corresponding to the target gear and the speed corresponding to the gear indicated by the brake release downshift requirement, the vehicle is controlled to downshift from the current gear to the gear indicated by the brake release downshift requirement.

[0071] S206: When a gear shift is detected, the vehicle is controlled to drive stably by using the clutch in the dual-clutch transmission that corresponds to the current gear.

[0072] During the specific execution of step S206, after the vehicle has completed the gear shift detection, that is, after the vehicle has shifted from the current gear to the target gear, or from the target gear to the gear indicated by the brake release downshift requirement, the vehicle is controlled to drive stably through the clutch in the vehicle's dual-clutch transmission that corresponds to the current gear of the vehicle (target gear, or gear indicated by the brake release downshift requirement).

[0073] In this embodiment of the application, when the downshifting demand of the vehicle is detected to change from braking to releasing the brake and downshifting, the vehicle can be controlled to downshift from the target gear to the gear indicated by the release brake downshifting demand by using a single clutch control and requesting EMS coordination.

[0074] See Figure 3The diagram illustrates a flowchart of another control method for a dual-clutch transmission provided by an embodiment of the present invention. This control method specifically includes the following steps:

[0075] S301: During vehicle coasting, detect in real time whether the vehicle needs to brake and downshift; if the vehicle needs to brake and downshift, execute step S302.

[0076] S302: Determine whether the braking downshift demand is a multi-gear downshift demand; if the braking downshift demand is a multi-gear downshift demand, proceed to step S303; if the braking downshift demand is a single-gear downshift demand, proceed to step S304.

[0077] Among them, the braking downshift requirement includes the target gear.

[0078] S303: Collects current operating condition information and, based on the current operating condition information and the target gear, controls the torque of the target clutch in the vehicle's dual-clutch transmission to maintain the target torque until the vehicle's current gear drops to the target gear.

[0079] The target torque is the torque corresponding to the gear indicated by the braking downshift requirement, and the target clutch is the clutch corresponding to the current gear in the vehicle's dual-clutch transmission.

[0080] S304: Uses coasting downshifting without throttle to downshift the vehicle's current gear to the gear indicated by the braking downshift requirement.

[0081] In the specific execution of steps S301 to S304, the specific execution process and implementation principle of steps S301 to S304 are the same as those disclosed in the above embodiments of the present invention. Figure 1 The specific execution process and implementation principle of steps S101 to S104 are the same, and can be found in the above-described embodiments of the present invention. Figure 1 The relevant parts are not elaborated here.

[0082] S305: During vehicle downshifting, if the current vehicle speed is detected to be greater than the preset vehicle speed threshold, and the driver presses the accelerator pedal, torque is transmitted through the current offgoing clutch in the vehicle's dual-clutch transmission.

[0083] During the execution of step S305, the vehicle speed is monitored in real time during downshifting. If the current vehicle speed is detected to be greater than the preset speed threshold and the driver presses the accelerator pedal, the downshifting control is directly initiated by pressing the accelerator pedal. This means that the torque is transmitted through the current offgoing clutch in the vehicle's dual-clutch transmission to complete the downshifting process.

[0084] S306: When a gear shift is detected, the vehicle is controlled to drive stably through the clutch in the dual-clutch transmission that corresponds to the current gear.

[0085] During the specific execution of step S306, after the vehicle has completed the gear shift detection, that is, after the vehicle has shifted from the current gear to the target gear, or from the target gear to the gear indicated by the brake release downshift requirement, the vehicle is controlled to drive stably through the clutch in the vehicle's dual-clutch transmission that corresponds to the current gear of the vehicle (target gear, or gear indicated by the brake release downshift requirement).

[0086] In this embodiment, during the downshifting process, the vehicle speed is detected in real time. If the current vehicle speed is detected to be greater than a preset speed threshold and the driver presses the accelerator pedal, the torque is transmitted through the current offgoing clutch in the dual-clutch transmission of the vehicle, which can ensure the power response when pressing the accelerator. This solves the problem in the prior art where, when the driver presses the accelerator pedal again after the two clutches are disengaged, pre-engagement and pre-charge are required to respond to the engine torque, resulting in slow power response when pressing the accelerator.

[0087] See Figure 4 The diagram illustrates a flowchart of another control method for a dual-clutch transmission provided by an embodiment of the present invention. This control method specifically includes the following steps:

[0088] S401: During vehicle coasting, detect in real time whether the vehicle needs to brake and downshift; if the vehicle needs to brake and downshift, execute step S402.

[0089] S402: Determine whether the braking downshift demand is a multi-gear downshift demand; if the braking downshift demand is a multi-gear downshift demand, proceed to step S403; if the braking downshift demand is a single-gear downshift demand, proceed to step S404.

[0090] Among them, the braking downshift requirement includes the target gear.

[0091] S403: Collects current operating condition information and, based on the current operating condition information and the target gear, controls the torque of the target clutch in the vehicle's dual-clutch transmission to maintain the target torque until the vehicle's current gear drops to the target gear.

[0092] The target torque is the torque corresponding to the gear indicated by the braking downshift requirement, and the target clutch is the clutch corresponding to the current gear in the vehicle's dual-clutch transmission.

[0093] S404: Uses coasting downshifting without throttle to downshift the vehicle's current gear to the gear indicated by the braking downshift requirement.

[0094] In the specific execution of steps S401 to S404, the specific execution process and implementation principle of steps S401 to S404 are the same as those disclosed in the above embodiments of the present invention. Figure 1 The specific execution process and implementation principle of steps S101 to S104 are the same, and can be found in the above-described embodiments of the present invention. Figure 1 The relevant parts are not elaborated here.

[0095] S405: During downshifting, if the current vehicle speed is detected to be lower than the preset speed threshold, and the driver presses the accelerator pedal, the engine speed is increased to the preset speed, and the vehicle's current gear is switched to the gear corresponding to the preset speed.

[0096] During the execution of step S405, the vehicle speed is monitored in real time during downshifting. If the current vehicle speed is detected to be less than the preset speed threshold and the driver presses the accelerator pedal, the vehicle directly enters the start-up control slip control. That is, after the engine speed is increased to the preset speed, the dual-clutch transmission is switched to the gear corresponding to the preset speed, so that the vehicle can start.

[0097] S406: When a gear shift is detected, the vehicle is controlled to drive stably through the clutch in the dual-clutch transmission that corresponds to the current gear.

[0098] During the specific execution of step S406, after the vehicle has completed the gear shift, the dual-clutch transmission is switched to the gear corresponding to the preset speed. The clutch in the dual-clutch transmission that corresponds to the current gear (the gear corresponding to the preset speed) controls the vehicle to drive stably.

[0099] In this embodiment of the application, after the vehicle starts, stable driving of the vehicle can be achieved by maintaining the clutch corresponding to the gear.

[0100] Based on the control method for a dual-clutch transmission disclosed in the embodiments of the present invention, the embodiments of the present invention also disclose a corresponding control device for a dual-clutch transmission, such as... Figure 5 As shown, the control device of the dual-clutch transmission includes:

[0101] The real-time detection unit 51 is used to detect in real time whether the vehicle needs to brake and downshift during the vehicle coasting process;

[0102] The judgment unit 52 is used to determine whether the braking downshifting demand is a braking downshifting demand if a braking downshifting demand is detected in the vehicle, wherein the braking downshifting demand carries a target gear.

[0103] The first downshift unit 53 is used to collect current operating condition information if the braking downshift requirement is a braking downshift requirement, and control the torque of the target clutch in the vehicle's dual-clutch transmission to maintain the target torque according to the current operating condition information and the target gear, until the vehicle downshifts from the current gear to the target gear. The target torque is the torque corresponding to the gear indicated by the braking downshift requirement, and the target clutch is the clutch in the vehicle's dual-clutch transmission corresponding to the current gear of the vehicle.

[0104] The second downshift unit 54 is used to downshift the vehicle from the current gear to the target gear by coasting downshifting without throttle if the braking downshifting requirement is a single-gear braking requirement.

[0105] The specific principles and execution processes of each unit in the control device of the dual-clutch transmission disclosed in the above embodiments of the present invention are the same as those of the control method of the dual-clutch transmission disclosed in the above embodiments of the present invention. Please refer to the corresponding parts of the control method of the dual-clutch transmission disclosed in the above embodiments of the present invention, and they will not be repeated here.

[0106] This invention provides a control device for a dual-clutch transmission. During vehicle coasting, the device detects in real time whether there is a braking downshift requirement. When a braking downshift requirement is detected, it determines whether the detected braking downshift requirement is a multi-gear downshift requirement. If the detected braking downshift requirement is determined to be a multi-gear downshift requirement, the device collects current operating condition information. Based on the collected current operating condition information and the target gear indicated by the braking downshift requirement, the device controls the torque of the target clutch in the dual-clutch transmission corresponding to the vehicle's current gear to maintain the target torque until the vehicle's current gear is downshifted to the target gear. If the braking downshift requirement is determined to be a single-gear downshift requirement rather than a multi-gear downshift requirement, the device uses a coasting downshift without throttle to downshift the vehicle's current gear to the gear indicated by the braking downshift requirement. The technical solution provided by this invention addresses the issue of rapid downshifting when a vehicle needs to downshift during braking. It controls the torque of the target clutch in the dual-clutch transmission corresponding to the vehicle's current gear to maintain the target torque based on current operating conditions and the target gear required for downshifting. This process continues until the vehicle's current gear is downshifted to the target gear, achieving rapid downshifting. This solves problems such as delayed downshifting during coasting braking, leading to stalling at low speeds in high gears, frequent clutch engagement, jerking noise, and weak accelerator power.

[0107] Furthermore, the control device for the dual-clutch transmission provided by the present invention further includes:

[0108] The third downshifting unit is used to control the vehicle to downshift from the target gear to the gear indicated by the brake release downshifting requirement when the downshifting requirement of the vehicle is detected to change from a brake release downshifting requirement. This is achieved by using single-clutch control and requesting EMS coordination.

[0109] Furthermore, the control device for the dual-clutch transmission provided by the present invention further includes:

[0110] The transmission unit is used to transmit torque through the current offgoing clutch in the vehicle's dual-clutch transmission when the current vehicle speed is detected to be greater than a preset vehicle speed threshold and the driver presses the accelerator pedal during the downshifting process, so as to control the vehicle to downshift from the current gear to the target gear.

[0111] Furthermore, the control device for the dual-clutch transmission provided by the present invention further includes:

[0112] The gear shifting unit is used to shift the vehicle's current gear to the gear corresponding to the preset speed when the vehicle is downshifting and the current speed is detected to be less than a preset speed threshold, and the driver presses the accelerator pedal.

[0113] Furthermore, the control device for the dual-clutch transmission provided by the present invention further includes:

[0114] The control unit is used to control the vehicle to drive stably by using the clutch in the dual-clutch transmission that corresponds to the current gear when the vehicle has completed a gear shift.

[0115] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and relevant parts can be referred to the descriptions in the method embodiments. The systems and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0116] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0117] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0118] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A control method for a dual-clutch transmission, characterized in that, The method includes: During vehicle coasting, the system continuously monitors whether the vehicle requires braking and downshifting. If a braking downshifting requirement is detected in the vehicle, it is determined whether the braking downshifting requirement is a multi-gear downshifting requirement, wherein the braking downshifting requirement carries a target gear. If the braking downshift requirement is a multi-gear downshift requirement, the current operating condition information is collected, and based on the current operating condition information and the target gear, the torque of the target clutch in the dual-clutch transmission of the vehicle is controlled to remain at the target torque until the vehicle downshifts from the current gear to the target gear. Here, the target torque is the torque corresponding to the gear indicated by the braking downshift requirement, and the target clutch is the clutch in the dual-clutch transmission of the vehicle corresponding to the current gear of the vehicle. If the braking downshift requirement is a single-gear downshift requirement, the vehicle is downshifted from the current gear to the target gear by coasting downshifting without throttle. During the downshifting process, if the current vehicle speed is detected to be greater than a preset vehicle speed threshold and the driver presses the accelerator pedal, torque is transmitted through the current offgoing clutch in the dual-clutch transmission of the vehicle to control the vehicle to downshift from the current gear to the target gear. During the downshifting process, if the current vehicle speed is detected to be lower than a preset speed threshold, and the driver presses the accelerator pedal, the engine speed is increased to a preset speed, and then the current gear of the vehicle is switched to the gear corresponding to the preset speed.

2. The method according to claim 1, characterized in that, After the vehicle downshifts from the current gear to the target gear, the method further includes: When the downshifting demand of the vehicle is detected to change from a braking downshifting demand to a braking release downshifting demand, a single-clutch control and EMS coordination request method is used to control the vehicle to downshift from the target gear to the gear indicated by the braking release downshifting demand.

3. The method according to claim 1, characterized in that, The method further includes: Once the vehicle has completed a gear shift, the clutch in the vehicle's dual-clutch transmission corresponding to the current gear position controls the vehicle's stable driving.

4. A control device for a dual-clutch transmission, characterized in that, The device includes: The real-time detection unit is used to detect in real time whether the vehicle needs to brake and downshift during the vehicle's coasting process; The determination unit is used to determine whether the braking downshifting demand is a multi-gear downshifting demand if the vehicle is detected to have a braking downshifting demand, wherein the braking downshifting demand carries a target gear. The first downshift unit is used to collect current operating condition information if the braking downshift requirement is a multi-gear downshift requirement, and control the torque of the target clutch in the dual-clutch transmission of the vehicle to be maintained at the target torque according to the current operating condition information and the target gear, until the vehicle downshifts from the current gear to the target gear. The target torque is the torque corresponding to the gear indicated by the braking downshift requirement, and the target clutch is the clutch in the dual-clutch transmission of the vehicle corresponding to the current gear of the vehicle. The second downshift unit is used to downshift the vehicle from the current gear to the target gear by coasting downshifting without throttle if the braking downshifting requirement is a single-gear braking downshifting requirement. The transmission unit is used to transmit torque through the current offgoing clutch in the dual-clutch transmission of the vehicle when the current vehicle speed is detected to be greater than a preset vehicle speed threshold and the driver presses the accelerator pedal during the downshifting process of the vehicle, so as to control the vehicle to downshift from the current gear to the target gear. The gear shifting unit is used to, during the downshifting process of the vehicle, if it detects that the current vehicle speed is less than a preset vehicle speed threshold and the driver presses the accelerator pedal, increase the engine speed to a preset speed and then shift the current gear of the vehicle to the gear corresponding to the preset speed.

5. The apparatus according to claim 4, characterized in that, The device includes: The third downshift unit is used to control the vehicle to downshift from the target gear to the gear indicated by the brake release downshift requirement when the downshift requirement of the vehicle is detected to change from a brake release downshift requirement. This is achieved by using a single-clutch control and requesting EMS coordination.

6. The apparatus according to claim 4, characterized in that, The device includes: The control unit is used to control the vehicle to drive stably by means of the clutch in the dual-clutch transmission corresponding to the current gear of the vehicle when the vehicle has completed a gear shift.

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