Electrically driven gearbox shift control method and control device

Abstract

The application discloses a kind of electric drive gearbox shift control method and control device, its method includes: in response to obtaining shift signal, whether electric drive gearbox enters power shift mode is judged;In response to entering power shift mode, the oil pressure of current gear corresponding clutch is reduced, the pre-charging of target gear corresponding clutch is carried out, and the output torque of drive motor is reduced;In response to target gear corresponding clutch pre-charging completion, then current gear corresponding clutch oil pressure is continuously reduced, and target gear corresponding clutch oil pressure is continuously improved;In response to current gear corresponding clutch oil pressure drop to 0, then target gear corresponding clutch oil pressure is continuously improved, and the output torque of drive motor is continuously reduced;In response to target gear corresponding clutch front and rear speed difference less than set value, then target gear corresponding clutch oil pressure is improved to maximum value, and the output torque of drive motor is improved to target value;The application can improve the smoothness and safety of shift, shorten the time of shift.

Description

Technical Field

[0001] This invention relates to the field of engineering machinery technology, and in particular to an electric drive gearbox shifting control method and control device. Background Technology

[0002] With the increasing demand for energy conservation and emission reduction in the construction machinery market, an electric fully automatic transmission has been developed to address this need. The electric fully automatic transmission uses a wet clutch for power transmission, enabling uninterrupted control of the machine's power. The disengagement and engagement of the wet clutch, as well as its coordinated control with the drive motor, are particularly crucial during gear shifting.

[0003] In the field of automatic transmissions, AMT transmissions currently use a sliding sleeve method to achieve speed synchronization, which can reduce shift time and the risk of burning of the synchronization device. However, sliding sleeve shifting inevitably brings shift shock problems, and the risk of unsuccessful shifting on the first attempt is also relatively high. Using a wet clutch for control, if speed synchronization control is employed, will cause torque fluctuations during shifting, leading to shift shock. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide an electric drive gearbox shift control method and control device to solve the technical problem that the existing gearboxes are not smooth enough during the shifting process and are prone to safety hazards such as shift shock.

[0005] To achieve the above objectives, the present invention is implemented using the following technical solution:

[0006] In a first aspect, the present invention provides a method for shifting control of an electric drive transmission, comprising:

[0007] In response to receiving a shift signal, the accelerator pedal opening and drive motor output torque are obtained; based on the shift signal, accelerator pedal opening and drive motor output torque, it is determined whether the electric drive transmission has entered power shift mode;

[0008] In response to entering power shift mode, the drive motor output torque adjustment coefficient during the clutch slippage stage in power shift mode is obtained; the oil pressure of the clutch corresponding to the current gear is reduced to the first oil pressure setting value, the clutch corresponding to the target gear is pre-charged to the second oil pressure setting value, and the drive motor output torque is reduced to the torque setting value.

[0009] In response to the completion of pre-charging of the clutch corresponding to the target gear, the oil pressure of the clutch corresponding to the current gear is continuously reduced by the first slope value, and the oil pressure of the clutch corresponding to the target gear is continuously increased by the second slope value, so as to keep the output torque of the drive motor at the torque set value.

[0010] In response to the clutch oil pressure corresponding to the current gear dropping to 0, the clutch oil pressure corresponding to the current gear is kept at 0, the clutch oil pressure corresponding to the target gear is continuously increased with the third slope value, and the drive motor output torque is continuously reduced with the fourth slope value.

[0011] In response to the target gear corresponding to the clutch speed difference being less than the first speed difference setting value, the clutch oil pressure corresponding to the current gear is kept at 0. During the first time period, the clutch oil pressure corresponding to the target gear is increased to the maximum value. During the second time period, the drive motor output torque is increased to the torque value corresponding to the accelerator pedal opening, and the gear shift is completed.

[0012] Optionally, determining whether the electric drive transmission has entered power shift mode based on the shift signal, accelerator pedal opening, and drive motor output torque includes:

[0013] If the shift signal is an upshift signal, and the accelerator pedal opening is greater than the upshift opening threshold or the drive motor output torque is greater than the upshift torque threshold, then the power upshift mode is entered.

[0014] If the shift signal is a downshift signal, and the accelerator pedal opening is less than the downshift opening threshold or the drive motor output torque is less than the downshift torque threshold, then the power downshift mode is entered.

[0015] Optional,

[0016] The first oil pressure setting value is obtained by calibrating to keep the speed difference between the front and rear clutches corresponding to the current gear close to 0;

[0017] The second oil pressure setting value is obtained by filling the oil supply passage of the clutch corresponding to the target gear and maintaining it at the KissPoint point of the clutch corresponding to the target gear.

[0018] The torque setting value is obtained by calibration while keeping the overall vehicle power performance unchanged.

[0019] Optional,

[0020] The first slope value and the second slope value are obtained by calibration while keeping the change in the output torque of the drive motor close to 0.

[0021] Optional,

[0022] The third slope value is obtained by keeping the change in the output torque of the drive motor close to 0 and achieving synchronous sliding friction of the clutch corresponding to the target gear under calibration;

[0023] The fourth slope value is obtained by multiplying the reference slope of the change in the output torque of the drive motor by the adjustment coefficient of the output torque of the drive motor during the clutch slippage stage.

[0024] Optionally, the step of obtaining the drive motor output torque adjustment coefficient during the clutch slippage stage in power shift mode includes:

[0025] If the shifting slip time t in power shift mode m ∈[0, t min ],but:

[0026] β MCU (N)=β MCU (N-1)×β min

[0027] If the shifting slip time t in power shift mode m ∈[t min , t Th1 ],but:

[0028]

[0029] If the shifting slip time t in power shift mode m ∈[t Th1 , t Th2 ],but:

[0030] β MCU (N)=β MCU (N-1)×β hold

[0031] If the shifting slip time t in power shift mode m ∈[t Th2 , t max ],but:

[0032]

[0033] If the shifting slip time t in power shift mode m ∈[t max If [+∞], then:

[0034] β MCU (N)=β MCU (N-1)×β Max

[0035] In the formula, β MCU (N), β MCU (N-1) represents the adjustment coefficients for the current and previous gear shifts, β min β max t represents the correction factors corresponding to the minimum and maximum slip times. min t max For the minimum and maximum slip times, [t] Th1 , t Th2 To determine the reasonable range of slippage time, β hold For [t] Th1， t Th2 The correction factor within ]

[0036] Optionally, during the execution of the control method, the following is always maintained:

[0037] V 驱 ≤V 变 *K 目

[0038] In the formula, V 驱 V 变 K is the output speed of the drive motor and gearbox. 目 The gear ratio for the target gear.

[0039] In a second aspect, the present invention provides an electric drive gearbox shift control device, the control device comprising:

[0040] The first response module is used to respond to the acquisition of the shift signal, acquire the accelerator pedal opening and the output torque of the drive motor; and determine whether the electric drive transmission has entered the power shift mode based on the shift signal, the accelerator pedal opening and the output torque of the drive motor.

[0041] The second response module is used to respond to entering the power shift mode, obtain the drive motor output torque adjustment coefficient during the clutch slippage stage in the power shift mode; reduce the clutch oil pressure corresponding to the current gear to the first oil pressure setting value; precharge the clutch corresponding to the target gear to the second oil pressure setting value; and reduce the drive motor output torque to the torque setting value.

[0042] The third response module is used to respond to the completion of pre-charging of the clutch corresponding to the target gear, by continuously reducing the clutch oil pressure of the current gear with a first slope value and continuously increasing the clutch oil pressure of the target gear with a second slope value, so as to keep the output torque of the drive motor at the torque set value.

[0043] The fourth response module is used to respond to the current gear corresponding to the clutch oil pressure dropping to 0, then keep the current gear corresponding to the clutch oil pressure at 0, continuously increase the target gear corresponding to the clutch oil pressure with the third slope value, and continuously reduce the drive motor output torque with the fourth slope value.

[0044] The fifth response module is used to respond when the speed difference between the front and rear clutches corresponding to the target gear is less than the first speed difference setting value. In this case, the oil pressure of the clutch corresponding to the current gear is kept at 0. During the first time period, the oil pressure of the clutch corresponding to the target gear is increased to the maximum value. During the second time period, the output torque of the drive motor is increased to the torque value corresponding to the accelerator pedal opening, and the gear shift is completed.

[0045] Thirdly, the present invention provides an electronic device, including a processor and a storage medium;

[0046] The storage medium is used to store instructions;

[0047] The processor is used to perform the steps of the above method according to the instructions.

[0048] Fourthly, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-described method.

[0049] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0050] This invention provides an electric drive transmission shift control method and control device, which: 1. Appropriately reduce the clutch input torque during the clutch torque exchange phase, thereby reducing the clutch torque exchange time and overall shift time while ensuring the acceleration performance of the vehicle; 2. Continuously and dynamically reduce the clutch input torque during the clutch slippage phase, which can quickly achieve speed synchronization, reasonably control the clutch slippage time, reduce power loss, and improve the smoothness of the shift process; 3. Limit the maximum allowable output speed of the drive motor in real time throughout the entire shift process of the transmission, preventing the drive motor from running away and improving the safety and controllability of the shift process of the control system. Attached Figure Description

[0051] Figure 1 This is a flowchart illustrating the electric drive gearbox shift control method provided in an embodiment of the present invention;

[0052] Figure 2 This is a schematic diagram illustrating the correction of the drive motor output torque adjustment coefficient provided in an embodiment of the present invention;

[0053] Figure 3 This is a connection diagram of the electric drive gearbox shift control system provided in an embodiment of the present invention;

[0054] Figure 4 This is a schematic diagram showing the connection between the power shift transmission and the electric drive transmission shift control system provided in an embodiment of the present invention;

[0055] Figure 5 This is a flowchart illustrating the control process of the electric drive gearbox shifting control system provided in an embodiment of the present invention.

[0056] Figure 6 This is a timing diagram of the allowable output speed of the drive motor, the output torque of the drive motor, and the torque exchange control of the clutch provided in the embodiment of the present invention. Detailed Implementation

[0057] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0058] Example 1:

[0059] like Figure 1 As shown, this embodiment of the invention provides a shift control method for an electric drive transmission, comprising the following steps:

[0060] Step S1: In response to receiving the shift signal, obtain the accelerator pedal opening and the drive motor output torque; determine whether the electric drive transmission has entered the power shift mode based on the shift signal, accelerator pedal opening and drive motor output torque;

[0061] In this embodiment, the logic for determining whether to enter the power shift mode is as follows:

[0062] If the shift signal is an upshift signal, and the accelerator pedal opening is greater than the upshift opening threshold or the drive motor output torque is greater than the upshift torque threshold, then the power upshift mode is entered.

[0063] If the shift signal is a downshift signal, and the accelerator pedal opening is less than the downshift opening threshold or the drive motor output torque is less than the downshift torque threshold, then the power downshift mode is entered.

[0064] Step S2: In response to entering the power shift mode, obtain the drive motor output torque adjustment coefficient during the clutch slippage stage in the power shift mode; reduce the clutch oil pressure corresponding to the current gear to the first oil pressure setting value, precharge the clutch corresponding to the target gear to the second oil pressure setting value, and reduce the drive motor output torque to the torque setting value.

[0065] like Figure 2 As shown, in this embodiment, obtaining the drive motor output torque adjustment coefficient during the clutch slippage stage in power shift mode includes:

[0066] If the shifting slip time t in power shift mode m ∈[0, t min ],but:

[0067] β MCU (N)=β MCU (N-1)×β min

[0068] If the shifting slip time t in power shift mode m ∈[t min , t Th1 ],but:

[0069]

[0070] If the shifting slip time t in power shift mode m ∈[t Th1 , t Th2 ],but:

[0071] β MCU (N)=βMCU (N-1)×β hold

[0072] If the shifting slip time t in power shift mode m ∈[t Th2 , t max ],but:

[0073]

[0074] If the shifting slip time t in power shift mode m ∈[t max If [+∞], then:

[0075] β MCU (N)=β MCU (N-1)×β Max

[0076] In the formula, β MCU (N), β MCU (N-1) represents the adjustment coefficients for the current and previous gear shifts, β min β max t represents the correction factors corresponding to the minimum and maximum slip times. min t max For the minimum and maximum slip times, [t] Th1 , t Th2 To determine the reasonable range of slippage time, β hold For [t] Th1 , t Th2 The correction factor within ]

[0077] In this embodiment, obtaining the first oil pressure setting value, the second oil pressure setting value, and the torque setting value includes:

[0078] The first oil pressure setting value is obtained by calibrating to keep the speed difference between the front and rear clutches corresponding to the current gear close to 0.

[0079] The second oil pressure setting value is obtained by filling the oil supply passage of the clutch corresponding to the target gear and maintaining it at the KissPoint (the half-engagement point of a wet dual-clutch automatic transmission, which is the critical pressure point at which the clutch can just transmit torque) of the clutch corresponding to the target gear.

[0080] The torque setting value is obtained by calibration while keeping the overall vehicle power performance unchanged.

[0081] Step S3: In response to the completion of pre-charging of the clutch corresponding to the target gear, the oil pressure of the clutch corresponding to the current gear is continuously reduced by the first slope value, and the oil pressure of the clutch corresponding to the target gear is continuously increased by the second slope value, so as to keep the output torque of the drive motor at the torque set value.

[0082] In this embodiment, the first slope value and the second slope value are obtained by calibration while keeping the change in the output torque of the drive motor close to 0.

[0083] Step S4: In response to the clutch oil pressure corresponding to the current gear dropping to 0, the clutch oil pressure corresponding to the current gear is kept at 0, the clutch oil pressure corresponding to the target gear is continuously increased with the third slope value, and the drive motor output torque is continuously reduced with the fourth slope value.

[0084] In this embodiment, obtaining the third slope value and the fourth slope value includes:

[0085] The third slope value is obtained by keeping the change in the output torque of the drive motor close to 0 and achieving the sliding friction synchronization of the clutch corresponding to the target gear under calibration;

[0086] The fourth slope value is obtained by multiplying the reference slope of the change in the output torque of the drive motor by the adjustment coefficient of the output torque of the drive motor during the clutch slippage stage.

[0087] Step S5: In response to the target gear's clutch speed difference being less than the first speed difference setting value, the clutch oil pressure corresponding to the current gear is kept at 0. During the first time period, the clutch oil pressure corresponding to the target gear is increased to its maximum value. During the second time period, the drive motor output torque is increased to the torque value corresponding to the accelerator pedal opening, completing the gear shift. The first and second time periods should be as short as possible to ensure stable operation.

[0088] To prevent the drive motor from running away, the control method maintains the following during execution:

[0089] V 驱 ≤V 变 *K 目

[0090] In the formula, V 驱 V 变 K is the output speed of the drive motor and gearbox. 目 The gear ratio for the target gear.

[0091] Example 2:

[0092] like Figure 3 As shown, this embodiment provides an electric drive transmission shift control system. The electric drive transmission shift control system consists of a transmission control unit (TCU), a drive motor control unit (MCU), an electric oil pump control unit (EOP), a vehicle control unit (VCU), a power battery, an accelerator pedal, a shift lever, and a speed sensor. The MCU and EOP are connected to the power battery via high-voltage wiring harnesses. The shift lever and speed sensor are connected to the TCU, and the accelerator pedal is connected to the VCU. Information exchange between the TCU, MCU, EOP, and VCU is completed via a CAN bus.

[0093] The transmission control unit (TCU) receives information from the gear shift lever to determine whether the transmission is in a shifting state; it also receives information from input and output speed sensors to calculate the speed difference before and after clutch engagement during shifting, determine whether slippage is complete, and record the slippage time t. m The TCU collects the actual output torque and output speed of the drive motor via the bus to determine whether the torque threshold T is triggered. Th The system collects real-time speed data of the electric oil pump to determine if it exceeds the pump's output capacity, and collects the transmission input speed to determine the actual engagement state during gear shifts. The vehicle control unit (VCU) receives the accelerator pedal signal to determine if the accelerator pedal threshold θ has been reached. Th Used to determine the shifting conditions of the transmission.

[0094] like Figure 4 As shown in the diagram, this embodiment provides a connection schematic of a three-clutch power shift transmission and an electric drive transmission shift control system. The TCU directly controls the wet clutch inside the power shift transmission via a wiring harness, and achieves the exchange of shift torque by providing different current curves. The drive motor is directly connected to the power shift transmission. The TCU sends torque requirements to the MCU via the CAN bus according to needs. The MCU changes the corresponding drive current, thereby changing the input torque of the power shift transmission. The transmission provides a pressurized oil source through the EOP to provide pressure to the wet clutch and lubricate the power shift transmission bearings and other components. The transmission output shaft is directly connected to the vehicle's drive shaft or drive axle to drive the wheels and tires.

[0095] The three-clutch power shift transmission uses three clutches (C1, C2, C3) to create three forward gears (F1, F2, F3) and three reverse gears (R1, R2, R3). It has no directional clutch and achieves forward or reverse movement by changing the rotation direction of the drive motor. The shift logic table is shown in Table 1.

[0096] Table 1: Transmission Shift Logic Table

[0097] C1 C2 C3 F1 √ F2 √ F3 √ R1 √ R2 √ R3 √

[0098] Taking the forward movement F1 (C1) to the forward movement F2 (C2) as an example: Based on the control method proposed in Example 1, the control process is as follows: Figure 5 As shown, it includes:

[0099] Step 1: First, the TCU acquires the shift lever signal. If it detects an F1 to F2 shift, it collects information on the accelerator pedal and the output torque of the drive motor at that moment. If the accelerator pedal opening θ at that moment... Ped >θ Th Or the output torque T of the drive motor MCU >T ThThe test can determine whether the electric drive transmission has entered power upshift mode, and based on the output torque T of the drive motor at this time... MCU Different torque ranges are set according to the magnitude of the torque; based on the set torque range, the output torque of the drive motor is adjusted by reading the value of this range and combining it with the clutch slippage stage adjustment coefficient β. MCU This is used as the calculation coefficient for setting the torque of the drive motor during this gear shift.

[0100] The gear shift is categorized based on the output torque of the drive motor at the moment of gear change, for example,

[0200] , [200600], [6001000], [10001500], [15002000], [2000 Maximum output torque of drive motor], with an adjustment coefficient β. MCU The default value is 1. This value will be recalculated based on the slippage time monitored during gear shifting within the specified range. For example, when shifting from F1 to F2, if the drive motor output torque is between [200-600], the adjustment coefficient β will be adjusted during the first gear shift. MCU =1, the shifting process will calculate the slippage time of this shift. If the slippage time is too long, this adjustment coefficient β will be adjusted. MCU The adjustment factor β will be adjusted based on the corresponding relationship > 1; if the slippage time is too long, this adjustment factor β will be adjusted accordingly. MCU The adjustment coefficient β will be adjusted based on the correspondence relationship <1. MCU This will be recorded in the controller's memory and used again during the next torque range [200600] transition from F1 to F2 of the drive motor. The adjusted coefficient β will be used in this newer version. MCU And during this gear shift, the adjustment factor β is recalculated. MCU Continue adjusting until the gliding time is within a reasonable range.

[0101] Step 2: Reduce and maintain the C1 clutch oil pressure. At this time, the C1 oil pressure setting value should be such that there is no speed difference between the front and rear of the C1 clutch. Precharge the C2 clutch oil pressure. At this time, the C2 oil pressure setting value should be such that the C2 clutch oil supply passage is filled and maintained at the pressure value of the C2 clutch Kisspoint.

[0102] The set values ​​of C1 and C2 oil pressure can be calibrated by pressure sensors during bench testing. The C1 set value should be reduced to half of the original oil pressure value, and there should be no speed difference between the front and rear of the C1 clutch. The C2 set value is the pressure required to fill the oil supply passage of the C2 clutch. This pressure can be set to 80% of the maximum pressure of the C2 clutch, and whether the oil supply passage is filled is controlled by the filling time.

[0103] By appropriately reducing the output torque of the drive motor and controlling the input speed of the gearbox, the torque of the clutch can be prepared, which can appropriately reduce the time of subsequent clutch torque exchange, thereby reducing the overall shift time. At this time, the output torque of the drive motor is related to the overall vehicle speed and the engaged clutch, so that the overall vehicle power performance can be maintained. During the entire first stage of control, the maximum allowable output speed of the drive motor in this stage is calculated based on the current output speed of the drive motor, the overall vehicle speed, and the current shifting conditions. This speed value is used to limit the output speed of the drive motor to prevent the drive motor from running away.

[0104] The drive motor output torque is reduced to 85% of its original torque to maintain the overall vehicle power performance. This setting can be calibrated using a real vehicle, with different reduction values ​​set for different torque ranges. The torque range settings are as described above. Maximum permissible speed: Taking F1 to F2 as an example, the maximum permissible output speed of the drive motor = gearbox output speed × F2 gear ratio.

[0105] Step 3: Monitor the pre-charge time of clutch C2 in real time. If the set time has not been reached, continue with the operation in Step 2. If the set time has been reached, proceed to the next step.

[0106] The pre-charge time is the time it takes for the transmission oil in the C2 clutch to fill the oil passage. This time is obtained through bench calibration, and it is advisable that no pressure drop occurs in the Kisspoint section.

[0107] Step 4: After proceeding to the next step, continuously decrease the C1 clutch oil pressure at a certain slope and continuously increase the C2 clutch oil pressure at a certain slope. The slope setting in this stage should be adjusted to avoid output torque jitter. Maintain the drive motor output torque setting from the first stage of control to maintain the vehicle's power performance. Throughout the second stage of control, it is also necessary to calculate the maximum allowable output speed of the drive motor in this stage based on the current output speed of the drive motor, the overall vehicle speed, and the current shifting conditions. Use this speed value to limit the drive motor output speed to prevent the drive motor from running away.

[0108] The hydraulic pressure change slopes of clutches C1 and C2 were obtained through simulation testing. The basic value of the hydraulic pressure change slope of clutch C1 is 20 bar / s, and the basic value of the hydraulic pressure change slope of clutch C2 is 8 bar / s. These can be corrected through calibration by actual vehicle testing.

[0109] Step 5: Monitor and evaluate the C1 clutch oil pressure in real time. If the oil pressure does not drop to 0, continue with the operation in Step 4. If the oil pressure is 0, proceed to the next step.

[0110] The oil pressure decreases slowly. The feedback current of the C1 clutch solenoid valve is used to determine whether the given oil pressure is 0. That is, if the feedback current is 0, then the given oil pressure is 0.

[0111] Step 6: Keep the C1 clutch oil pressure at 0 and continuously increase the C2 clutch oil pressure at a certain slope. The slope setting at this stage should be such that the slip friction synchronization of the C2 clutch is achieved without causing output speed jitter. The slope of the C2 clutch oil pressure change is obtained through simulation test. The basic value of the C2 clutch oil pressure change slope is 8 bar / s, which can be corrected through actual vehicle test calibration.

[0112] During this phase, the output torque of the drive motor is continuously reduced, and the slope of the output torque change is:

[0113] k MCU =k ref ×β MCU (2-1)

[0114] Where: k MCU The slope of the change in output torque of the drive motor during this gear shift; k ref β serves as the reference slope for the change in output torque of the drive motor. MCU When entering the shifting condition, the controller reads the internal adjustment coefficient of the drive motor output torque change in combination with the clutch slippage stage.

[0115] The adjustment coefficient for the output torque of the drive motor is related to the slippage time of the C2 clutch during each gear shift:

[0116] If the slippage time t during this gear shift is m ∈[t Th1 , t Th2 That is, if the slippage time is within a reasonable slippage time, then the adjustment factor used for the next gear shift is:

[0117] Slippage time calculation: 1. Taking power upshift (F1 to F2) as an example, record from the moment the gear enters the inertia phase (clutch pressure of C1 drops to 0) until the speed difference between the front and rear of clutch C2 is monitored to be <30rpm. Record the time during this phase. 2. Taking power downshift (F2 to F1) as an example, record from the moment the gear enters the torque phase (clutch pressure slope of C2 increases) until the speed difference between the front and rear of clutch C1 is monitored to be <30rpm. Record the time during this phase.

[0118] β MCU (N)=β MCU (N-1)×β hold (2-2)

[0119] Where, β hold This is a correction factor for a reasonable friction time; a reasonable friction time is recommended to be 450-550 ms. Th1 This represents the lower limit of a reasonable friction time; t Th2 This represents the upper limit of a reasonable gliding time;

[0120] N represents the Nth gear shift under the same operating conditions, β MCU (N) is the adjustment factor for the next gear shift, β MCU (N-1) is the adjustment coefficient for this gear shift.

[0121] The correction factor and slip time are set the same for each shift condition and do not change with the shift condition. For each shift condition, the reasonable slip time is fixed, and the corresponding correction based on the slip time is also the same and fixed.

[0122] If the rubbing time t m ∈[t Th2 , t max Therefore, based on the linear relationship, the adjustment coefficient for the output torque change during the next gear shift is:

[0123]

[0124] Where, β max To set the correction factor corresponding to the maximum slip time, t max The maximum set friction time;

[0125] If the rubbing time t m ∈[t min , t Th1 Therefore, based on the linear relationship, the adjustment coefficient for the output torque change during the next gear shift is:

[0126]

[0127] Where, β min To set the correction factor corresponding to the minimum slip time, t min The minimum gliding time is set.

[0128] If the rubbing time t m >t max The adjustment factor used for the next gear shift is:

[0129] β MCU (N)=β MCU (N-1)×β max (2-5)

[0130] If the rubbing time t m <t min The adjustment factor used for the next gear shift is:

[0131] β MCU (N)=β MCU (N-1)×β min (2-6)

[0132] By monitoring and recording the slippage time of the C2 clutch, the adjustment coefficient for the change in output torque of the drive motor during the next gear shift is continuously adjusted. This allows the C2 clutch to synchronize quickly while ensuring controllable shift time. Each adjustment coefficient for the drive motor torque change is stored in a fixed memory space within the controller for easy retrieval during the next gear shift.

[0133] In addition, during the entire Phase III control process, it is also necessary to calculate the maximum allowable output speed of the drive motor in this phase based on the output speed of the drive motor, the overall vehicle speed, and the current shifting conditions, and use this speed value to limit the output speed of the drive motor to prevent the drive motor from running away.

[0134] Step 7: Monitor the speed difference between the front and rear of clutch C2 in real time using the input and output speed sensors of the transmission. If the speed difference of clutch C2 is n C2 ≥n C2，Th Then continue with step 6. If the speed difference n of clutch C2 is... C2 <n C2,Th Then proceed to the next step;

[0135] Step 8: After step 7, keep the C1 clutch oil pressure at 0 and quickly increase the C2 clutch oil pressure to its maximum value, so that the C2 clutch is in a pressed state; at this time, the torque exchange of the wet clutch is completed. In order to ensure the power performance of the whole vehicle, quickly increase the output torque of the drive motor to the torque value corresponding to the throttle opening; after completing this operation, disengage the limit on the maximum speed allowed to be output by the drive motor during gear shifting, and adjust the motor output speed according to the actual working conditions.

[0136] The maximum clutch oil pressure of C2 is the inherent value of this transmission, and also the system pressure of the transmission. By continuously increasing the solenoid valve current value, the opening of the solenoid valve is increased, and the clutch oil pressure is increased.

[0137] In this embodiment, the timing diagram for the control of the drive motor's allowed output speed, drive motor output torque, and clutch (C1, C2) torque exchange is as follows: Figure 6 As shown.

[0138] Example 3:

[0139] This invention provides an electric drive gearbox shift control device, the control device comprising:

[0140] The first response module is used to respond to the acquisition of the shift signal, acquire the accelerator pedal opening and the output torque of the drive motor; and determine whether the electric drive transmission has entered the power shift mode based on the shift signal, the accelerator pedal opening and the output torque of the drive motor.

[0141] The second response module is used to respond to entering the power shift mode, obtain the drive motor output torque adjustment coefficient during the clutch slippage stage in the power shift mode; reduce the clutch oil pressure corresponding to the current gear to the first oil pressure setting value; precharge the clutch corresponding to the target gear to the second oil pressure setting value; and reduce the drive motor output torque to the torque setting value.

[0142] The third response module is used to respond to the completion of pre-charging of the clutch corresponding to the target gear, by continuously reducing the clutch oil pressure of the current gear with a first slope value and continuously increasing the clutch oil pressure of the target gear with a second slope value, so as to keep the output torque of the drive motor at the torque set value.

[0143] The fourth response module is used to respond to the current gear corresponding to the clutch oil pressure dropping to 0, then keep the current gear corresponding to the clutch oil pressure at 0, continuously increase the target gear corresponding to the clutch oil pressure with the third slope value, and continuously reduce the drive motor output torque with the fourth slope value.

[0144] The fifth response module is used to respond when the speed difference between the front and rear clutches corresponding to the target gear is less than the first speed difference setting value. In this case, the oil pressure of the clutch corresponding to the current gear is kept at 0. During the first time period, the oil pressure of the clutch corresponding to the target gear is increased to the maximum value. During the second time period, the output torque of the drive motor is increased to the torque value corresponding to the accelerator pedal opening, and the gear shift is completed.

[0145] Example 4:

[0146] Based on Embodiment 1, this embodiment of the invention provides an electronic device, including a processor and a storage medium;

[0147] Storage media are used to store instructions;

[0148] The processor is used to perform the steps of the above method according to instructions.

[0149] Example 5:

[0150] Based on Embodiment 1, this embodiment of the invention provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the above-described method.

[0151] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0152] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0153] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0154] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0155] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles 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 shift control method for an electric drive transmission, characterized in that, include: In response to receiving a shift signal, the accelerator pedal opening and drive motor output torque are obtained; based on the shift signal, accelerator pedal opening and drive motor output torque, it is determined whether the electric drive transmission has entered power shift mode; In response to entering power shift mode, the drive motor output torque adjustment coefficient during the clutch slippage stage in power shift mode is obtained; the oil pressure of the clutch corresponding to the current gear is reduced to the first oil pressure setting value, the clutch corresponding to the target gear is pre-charged to the second oil pressure setting value, and the drive motor output torque is reduced to the torque setting value. In response to the completion of pre-charging of the clutch corresponding to the target gear, the oil pressure of the clutch corresponding to the current gear is continuously reduced by the first slope value, and the oil pressure of the clutch corresponding to the target gear is continuously increased by the second slope value, so as to keep the output torque of the drive motor at the torque set value. In response to the clutch oil pressure corresponding to the current gear dropping to 0, the clutch oil pressure corresponding to the current gear is kept at 0, the clutch oil pressure corresponding to the target gear is continuously increased with the third slope value, and the drive motor output torque is continuously reduced with the fourth slope value. In response to the target gear corresponding to the clutch speed difference being less than the first speed difference setting value, the clutch oil pressure corresponding to the current gear is kept at 0. During the first time period, the clutch oil pressure corresponding to the target gear is increased to the maximum value. During the second time period, the drive motor output torque is increased to the torque value corresponding to the accelerator pedal opening, and the gear shift is completed. Among them, the adjustment coefficient for the output torque of the drive motor during the clutch slippage stage in power shift mode includes: If the shifting slip time in power shift mode ,but: If the shifting slip time in power shift mode ,but: If the shifting slip time in power shift mode ,but: If the shifting slip time in power shift mode ,but: If the shifting slip time in power shift mode ,but: In the formula, This is the adjustment factor for this gear shift and the last gear shift. These are the correction factors corresponding to the minimum and maximum slip times. For minimum and maximum friction times, To ensure a reasonable range of gliding time, for Correction factor within.

2. The electric drive gearbox shift control method according to claim 1, characterized in that, The step of determining whether the electric drive transmission has entered power shift mode based on the shift signal, accelerator pedal opening, and drive motor output torque includes: If the shift signal is an upshift signal, and the accelerator pedal opening is greater than the upshift opening threshold or the drive motor output torque is greater than the upshift torque threshold, then the power upshift mode is entered. If the shift signal is a downshift signal, and the accelerator pedal opening is less than the downshift opening threshold or the drive motor output torque is less than the downshift torque threshold, then the power downshift mode is entered.

3. The electric drive gearbox shift control method according to claim 1, characterized in that, The first oil pressure setting value is obtained by calibrating to keep the speed difference between the front and rear clutches corresponding to the current gear close to 0; The second oil pressure setting value is obtained by filling the oil supply passage of the clutch corresponding to the target gear and maintaining it at the KissPoint point of the clutch corresponding to the target gear. The torque setting value is obtained by calibration while keeping the overall vehicle power performance unchanged.

4. The electric drive gearbox shift control method according to claim 1, characterized in that, The first slope value and the second slope value are obtained by calibration while keeping the change in the output torque of the drive motor close to 0.

5. The electric drive gearbox shift control method according to claim 1, characterized in that, The third slope value is obtained by keeping the change in the output torque of the drive motor close to 0 and achieving synchronous sliding friction of the clutch corresponding to the target gear under calibration; The fourth slope value is obtained by multiplying the reference slope of the change in the output torque of the drive motor by the adjustment coefficient of the output torque of the drive motor during the clutch slippage stage.

6. The electric drive gearbox shift control method according to claim 1, characterized in that, During the execution of the control method, the following is always maintained: In the formula, The output speed of the drive motor and gearbox, The gear ratio for the target gear.

7. A shift control device for an electric drive gearbox, characterized in that, The control device includes: The first response module is used to respond to the acquisition of the shift signal, acquire the accelerator pedal opening and the output torque of the drive motor; and determine whether the electric drive transmission has entered the power shift mode based on the shift signal, the accelerator pedal opening and the output torque of the drive motor. The second response module is used to respond to entering the power shift mode by acquiring the drive motor output torque adjustment coefficient during the clutch slippage stage in the power shift mode; reducing the clutch oil pressure corresponding to the current gear to a first oil pressure setting value; pre-charging the clutch corresponding to the target gear to a second oil pressure setting value; and reducing the drive motor output torque to a torque setting value. Acquiring the drive motor output torque adjustment coefficient during the clutch slippage stage in the power shift mode includes: If the shifting slip time in power shift mode ,but: If the shifting slip time in power shift mode ,but: If the shifting slip time in power shift mode ,but: If the shifting slip time in power shift mode ,but: If the shifting slip time in power shift mode ,but: In the formula, This is the adjustment factor for this gear shift and the last gear shift. These are the correction factors corresponding to the minimum and maximum slip times. For minimum and maximum friction times, To ensure a reasonable range of gliding time, for Correction factor within; The third response module is used to respond to the completion of pre-charging of the clutch corresponding to the target gear, by continuously reducing the clutch oil pressure of the current gear with a first slope value and continuously increasing the clutch oil pressure of the target gear with a second slope value, so as to keep the output torque of the drive motor at the torque set value. The fourth response module is used to respond to the current gear corresponding to the clutch oil pressure dropping to 0, then keep the current gear corresponding to the clutch oil pressure at 0, continuously increase the target gear corresponding to the clutch oil pressure with the third slope value, and continuously reduce the drive motor output torque with the fourth slope value. The fifth response module is used to respond when the speed difference between the front and rear clutches corresponding to the target gear is less than the first speed difference setting value. In this case, the oil pressure of the clutch corresponding to the current gear is kept at 0. During the first time period, the oil pressure of the clutch corresponding to the target gear is increased to the maximum value. During the second time period, the output torque of the drive motor is increased to the torque value corresponding to the accelerator pedal opening, and the gear shift is completed.

8. An electronic device, characterized in that, Including processor and storage media; The storage medium is used to store instructions; The processor is configured to operate according to the instructions to perform the steps of the method according to any one of claims 1-6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the program implements the steps of the method according to any one of claims 1-6.

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