CN108150642B - Six Quick-drying type DCT upshift process clutch actuation electrical fault fault tolerant control methods - Google Patents

Abstract

The present invention relates to a kind of six Quick-drying type DCT upshift process clutch actuation electrical fault fault tolerant control methods, to carry out faults-tolerant control to the possible breakdown of clutch actuation motor in torque phase and inertia phase stage, it is characterized in that, the possible breakdown operating condition of the clutch actuation motor includes: fault condition 1: upshift instruction is received when keeping off stable operation, high gear clutch actuation motor breaks down at this time；Fault condition 2: upshift process torque phase stage separation clutch actuation motor breaks down；Fault condition 3: upshift process torque phase stage engagement clutch actuation motor breaks down；Fault condition 4: upshift process inertia phase stage engagement clutch actuation motor breaks down.Compared with prior art, the present invention has many advantages, such as to be suitable for various faults situation, safe and efficient.

Description

Fault-tolerant control method for actuation motor of six-speed dry DCT (discrete cosine transformation) upshifting process clutch

Technical Field

The invention relates to the field of fault diagnosis and fault-tolerant control of an automatic gearbox, in particular to a fault-tolerant control method for an actuating motor of a clutch in a six-speed dry DCT (discrete cosine transformation) upshifting process.

Background

In the process of gear upshift, two clutches work alternately in the dry DCT, and as the gear shifting of the vehicle is frequent in the normal driving process and the probability of the failure of the clutch actuating mechanism in the gear upshift process is increased gradually along with the time, the fault-tolerant control method for the failure of the clutch actuating mechanism becomes more important. Li kang li is directed at wet DCT, a fault-tolerant control method for the fault of a clutch control valve is researched, when the control valve of the clutch 1 is in fault, a vehicle can only run in even gears, and when the control valve of the clutch 2 is in fault, the vehicle can only run in odd gears, and the fault-tolerant control method for the fault of the clutch control valve in the DCT gear lifting process is not researched. Because the DCT clutch actuating mechanism is the motor, corresponding fault-tolerant control methods are respectively formulated for the possible clutch actuating motor faults in each stage of the DCT gear-up process, and the vehicle can be ensured to continuously, safely and effectively run after the clutch actuating motor faults.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a fault-tolerant control method for a clutch actuating motor in a six-speed dry DCT (double clutch transmission) upshifting process.

The purpose of the invention can be realized by the following technical scheme:

a fault-tolerant control method for a clutch actuating motor in a six-speed dry DCT (dynamic gearbox) upshifting process is used for carrying out fault-tolerant control on possible faults of the clutch actuating motor in a torque phase stage and an inertia phase stage, and possible fault working conditions of the clutch actuating motor comprise:

fault condition 1: when a gear-up instruction is received during stable operation of the gear, the actuating motor of the high-gear clutch breaks down;

and (3) fault working condition 2: the actuation motor of the separation clutch at the torque phase stage of the gear-up process breaks down;

and (3) fault working condition: the actuation motor of the clutch is engaged to generate faults in the torque phase stage in the gear-up process;

and (4) fault working condition: and the actuation motor of the engagement clutch fails in the inertia phase stage of the gear-up process.

And when the possible fault working condition of the clutch actuating motor is the fault working condition 1, the clutch without the motor fault is adopted to finish the jump gear-up of the single clutch.

The single-clutch skip upshift specifically comprises the following steps:

the method comprises the steps of firstly separating a clutch corresponding to a low gear without motor faults, controlling a synchronizer to complete gear picking, idle stroke elimination and gear engaging after the clutch without motor faults is completely separated, controlling the clutch without motor faults to be engaged after gear engaging is completed, simultaneously adjusting the rotating speed of an engine to be synchronous with the rotating speed of a clutch driven disc of the clutch without motor faults, compressing the clutch without motor faults to the maximum displacement after the rotating speeds are synchronous, and simultaneously switching the torque of the engine to a value required by a driver to complete gear rising of the single-jump clutch.

When the possible fault working condition of the clutch actuating motor is the fault working condition 2, according to the faults of different grades of the clutch actuating motor, the aim of minimizing the impact degree of the whole vehicle is fulfilled by adopting a corresponding method to finish the control action.

The method is characterized in that the control action is completed by adopting a corresponding method according to the faults of different grades of the actuating motor of the separating clutch and with the aim of minimizing the impact degree of the whole vehicle, and comprises the following specific steps:

if the fault grade of the separating clutch actuating motor is 1, immediately stopping power supply of the motor, continuously engaging an engaging clutch without motor fault according to the corrected engaging rule, entering an inertia phase stage after the clutch without motor fault is completely disengaged, adjusting the rotating speed of the engine until the rotating speed of the engine is consistent with the rotating speed of a clutch driven disc without motor fault, keeping the transmission torque of the engaging clutch without motor fault unchanged in the process of engine speed regulation, quickly pressing the clutch without motor fault to the maximum displacement and switching the engine torque to the value required by a driver after the rotating speeds are synchronous, and entering high-gear stable operation;

if the fault grade of the separating clutch actuating motor is 2, separating the clutch with motor fault according to a separating rule determined by bang-bang control with time as the optimal performance index, continuing to engage the engaging clutch without motor fault according to a corrected engaging rule, entering an inertia phase stage after the clutch with motor fault is completely disengaged, adjusting the rotating speed of an engine until the rotating speed of the engine is consistent with the rotating speed of a clutch driven disc without motor fault, keeping the transmitting torque of the engaging clutch without motor fault unchanged in the process of engine speed regulation, quickly compressing the clutch without motor fault to the maximum displacement after the rotating speeds are synchronous, switching the engine torque to a required value of a driver, and entering high-gear stable operation;

and if the fault grade of the clutch separating actuating motor is 3, the upshift is completed according to the originally formulated control method of the torque phase stage of the upshift process.

When the possible fault working condition of the clutch actuating motor is the fault working condition 3, according to the faults of different grades of the engaging clutch actuating motor, the aim of minimizing the impact degree of the whole vehicle is fulfilled by adopting a corresponding method to finish the control action.

The method is characterized in that the control action is completed by adopting a corresponding method according to the faults of different grades of the actuating motor of the engaging clutch and with the aim of minimizing the impact degree of the whole vehicle, and comprises the following specific steps:

if the fault grade of the engagement clutch actuating motor is 1, immediately stopping power supply of the motor, re-engaging a separation clutch without motor fault according to an engagement rule in a certain proportional relation with the separation speed of the clutch with motor fault, entering an inertia phase stage after the clutch with motor fault is completely disengaged, adjusting the rotating speed of an engine until the rotating speed of the engine is consistent with the rotating speed of a clutch driven disc which is re-engaged without motor fault, keeping the transmission torque of the clutch which is re-engaged unchanged in the process of speed regulation of the engine, quickly compressing the clutch without motor fault to the maximum displacement and switching the torque of the engine to the required value of a driver after the rotating speeds are synchronous, and re-entering low-gear stable operation;

if the fault grade of the actuating motor of the engaging clutch is 2, the clutch with the motor fault is separated according to a separating rule determined by bang-bang control with time as the optimal performance index, at the moment, in order to ensure that the impact degree of the whole vehicle is minimum, the separating clutch without the motor fault is re-engaged according to an engaging rule in a certain proportional relation with the separating speed of the clutch with the motor fault, when the clutch with motor failure is completely disengaged, the inertia phase stage is entered, the engine speed is adjusted until the engine speed is consistent with the speed of the clutch driven plate which is not engaged again with motor failure, in the process of engine speed regulation, the transmission torque of the clutch which is re-engaged is kept unchanged, after the rotating speed is synchronized, the clutch which does not have motor fault is quickly compressed to the maximum displacement, the engine torque is switched to a value required by a driver, and the engine enters the low-gear stable operation again;

if the fault grade of the engaging clutch actuating motor is 3, the upshift is completed according to the originally established control method of the torque phase stage of the upshift process.

When the possible fault working condition of the clutch actuating motor is the fault working condition 4, according to the faults of different grades of the engaging clutch actuating motor, the aim of minimizing the impact degree of the whole vehicle is fulfilled by adopting a corresponding method to finish the control action.

The method is characterized in that the control action is completed by adopting a corresponding method according to the faults of different grades of the actuating motor of the engaging clutch and with the aim of minimizing the impact degree of the whole vehicle, and comprises the following specific steps:

if the fault grade of the engaging clutch actuating motor is 1, immediately stopping the power supply of the motor, adjusting the rotating speed of the engine until the rotating speed of the engine is consistent with the rotating speed of a clutch driven disc which does not have motor fault and is completely separated in the process of separating the clutch with the motor fault, after the clutch with the motor fault is completely separated and the rotating speeds of a clutch main driven disc and a clutch driven disc which do not have motor fault are consistent, re-engaging and quickly pressing the clutch which does not have motor fault and is completely separated to the maximum displacement, switching the torque of the engine to the value required by a driver, and re-entering the low-gear stable operation;

if the fault grade of an actuating motor of an engaged clutch is 2, the clutch with the motor fault is separated according to a separation rule obtained by bang-bang control with time as the optimal performance index, in the process of separating the clutch with the motor fault, the rotating speed of an engine is adjusted until the rotating speed of the clutch is consistent with the rotating speed of a clutch driven disc which does not have the motor fault and is completely separated, and after the clutch with the motor fault is completely separated and the rotating speed of a clutch main driven disc which does not have the motor fault is consistent with the rotating speed of the clutch driven disc which does not have the motor fault, the clutch which is completely separated at the moment without the motor fault is re-engaged and quickly pressed to the maximum displacement, the engine torque is switched to the value required by a driver, and the clutch enters;

and if the fault grade of the engaging clutch actuating motor is 3, finishing the gear-up by following the originally established control method of the inertia phase stage of the gear-up process.

The joint rule of the certain proportional relation is as follows:

wherein,the transfer torque change rate of the off-going clutch where no motor failure has occurred,rate of change of transmission torque of disconnect clutch for motor failure, i₁Transmission ratio of gearbox corresponding to separating clutch without motor fault₂The gear ratio of the gearbox corresponding to the separating clutch with motor failure.

Compared with the prior art, the invention has the following advantages:

the invention makes full use of the structural redundancy characteristic of the DCT with double clutches and actuating mechanisms thereof to formulate a fault-tolerant control method for the faults of the actuating motor of the clutch in the DCT upshifting process, and has the advantages that:

1. the DCT vehicle receives a gear-up instruction when the gear stably runs, but the actuating motor of the clutch at the high gear breaks down at the moment, the jumping gear-up can be realized by utilizing the fault-tolerant control method established by the invention, and the vehicle can still continuously, safely and efficiently run at a higher speed after one of the actuating motors of the clutch breaks down;

2. if the DCT vehicle breaks down in the torque phase stage of the gear-up process, the fault-tolerant control method established by the invention can be utilized to ensure that the vehicle continues to finish the gear-up operation after the clutch actuating motor breaks down, so that the vehicle can run efficiently;

3. if the DCT vehicle is in failure in the torque phase stage in the gear-up process and is engaged with the clutch actuating motor, the fault-tolerant control method formulated by the invention can be utilized to enable the vehicle to return to the low gear for running again after the clutch actuating motor is in failure, thereby effectively avoiding the problem that the engine power cannot be directly transmitted to the whole vehicle due to the failure of the clutch actuating motor to cause the vehicle to be incapable of running normally.

4. If the DCT vehicle is in failure in the inertia phase stage in the gear-up process and is connected with the clutch actuating motor, the fault-tolerant control method formulated by the invention can be utilized to ensure that the vehicle can return to the low gear again to stably run after the clutch actuating motor is in failure, and the vehicle can be ensured to continue to safely and efficiently run after the clutch actuating motor is in failure.

Drawings

Fig. 1 is a fault-tolerant control method for a DCT vehicle receiving an upshift command when the 1 st gear stably operates at 30% pedal opening, but a clutch actuator corresponding to the 2 nd gear fails, where fig. 1a is an engine and clutch torque curve, fig. 1b is an engine and clutch speed curve at a clutch disengagement stage, and fig. 1c is an engine and clutch speed curve at a clutch engagement stage.

Fig. 2 is a fault-tolerant control method for a 1-stage fault of a clutch actuator motor corresponding to a 1-gear in a torque phase stage of a DCT vehicle 1-gear upshift 2-gear process under 30% accelerator pedal opening, where fig. 2a is an engine and clutch torque curve and fig. 2b is an engine and clutch rotation speed curve.

Fig. 3 is a fault-tolerant control method for a 2-stage fault of a clutch actuator corresponding to a 1-gear stage in a torque phase stage of a DCT vehicle 1-gear up-shift 2-gear stage at 30% accelerator pedal opening, where fig. 3a is an engine and clutch torque curve and fig. 3b is an engine and clutch rotation speed curve.

Fig. 4 is a fault-tolerant control method for a stage 1 fault of a clutch actuator motor corresponding to a 2-gear in a torque phase stage of a DCT vehicle 1-gear upshift 2-gear process under 30% accelerator pedal opening, where fig. 4a is an engine and clutch torque curve and fig. 4b is an engine and clutch rotation speed curve.

Fig. 5 is a fault-tolerant control method for a 2-stage fault of a clutch actuator motor corresponding to a 2-gear in a torque phase stage of a DCT vehicle 1-gear upshift 2-gear process under 30% accelerator pedal opening, where fig. 5a is an engine and clutch torque curve and fig. 5b is an engine and clutch rotation speed curve.

Fig. 6 shows a fault-tolerant control method for a class 1 fault of a clutch actuator motor corresponding to a 2-gear shift in a phase of inertia phase during a 1-gear shift and a 2-gear shift of a DCT vehicle at 30% opening of an accelerator pedal, where fig. 6a is a torque curve of an engine and a clutch, and fig. 6b is a rotational speed curve of the engine and the clutch.

Fig. 7 is a fault-tolerant control method for a 2-stage fault of a clutch actuator motor corresponding to a 2-gear in an inertia phase stage of a DCT vehicle 1-gear upshift 2-gear process under 30% accelerator pedal opening, where fig. 7a is an engine and clutch torque curve and fig. 7b is an engine and clutch rotation speed curve.

Fig. 8 is a schematic diagram of a fault-tolerant control strategy for fault condition 1.

FIG. 9 is a schematic diagram of a fault-tolerant control strategy for fault condition 2.

FIG. 10 is a schematic diagram of a fault tolerant control strategy for fault condition 3.

FIG. 11 is a schematic diagram of a fault tolerant control strategy for fault condition 4.

Detailed Description

Embodiments of the present invention will now be described with reference to the accompanying drawings and specific examples, it being understood that the examples described are only some, and not all, of the examples of the present invention. Based on the embodiment of the invention, the fault tolerance method of the clutch actuating motor in the six-speed dry DCT downshift process belongs to the protection scope of the invention.

The method for diagnosing the fault of the clutch actuating motor in the six-speed dry DCT upshifting process is the parameter state estimation of the clutch actuating motor. The current state of the motor is judged by estimating the parameters and the state of the clutch actuating motor in real time, so that the motor is subjected to fault diagnosis. The estimated parameters and states mainly include: resistance R and back electromotive force coefficient k of turn-to-turn winding_eAnd motor bus current I. Because the number of turns of the inter-turn winding is approximately in direct proportion to the resistance value of the inter-turn winding, and the resistance value of the inter-turn winding directly influences the magnitude of the bus current, the inter-turn short circuit fault of the motor can be diagnosed by estimating the resistance value of the inter-turn winding and the magnitude of the bus current; when the temperature of the motor rises (drops), the resistance value of the inter-turn winding of the motor can be increased (reduced), and the change of the resistance value of the inter-turn winding can directly influence the magnitude of the bus current, so that the over-temperature fault of the motor can be diagnosed by estimating the resistance value of the inter-turn winding and the magnitude of the bus current. Since the magnetic field intensity of the motor permanent magnet is in positive correlation with the back electromotive force coefficient, the demagnetization fault of the motor can be diagnosed by estimating the back electromotive force coefficient of the clutch actuating motor.

The classification of the failure class of the clutch actuator motor is based on its parameters (R, k)_e) For turn-to-turn short circuit faults of the stator winding of the motorWhen R is less than or equal to 0.5R₀Time is defined as a primary fault, 0.5R₀＜R≤0.7R₀Time is defined as a secondary fault, 0.7R₀＜R≤0.95R₀Is defined as a three-level fault, where R₀Is the resistance value of the motor winding in the normal state. For the motor over-temperature fault, the motor winding insulation grade is B, the highest temperature which can be borne by the motor insulation material is 130 ℃, so that the motor over-temperature fault is defined as a primary fault when the motor temperature exceeds 130 ℃, the motor over-temperature fault is defined as a secondary fault when the motor temperature is 80-130 ℃, and the motor over-temperature fault is defined as a tertiary fault when the motor temperature is 50-80 ℃. By using the relation R ═ between the resistance of the motor winding and the motor temperature ((T + K)/(T)₀+K))R₀(K＝235，T₀The temperature is the ambient temperature and is 26 degrees), the critical temperature for dividing the fault grade can be converted into the resistance value of the critical winding, and the dividing result is that when R is more than or equal to 1.4R₀Time is defined as a primary fault, 1.4R₀＞R≥1.22R₀Time is defined as a secondary fault, 1.22R₀＞R≥1.1R₀Time is defined as a three-level fault. For a demagnetization fault of the motor, when k is_e≤0.5k₀Time is defined as the primary fault, 0.5k₀＜k_e≤0.8k₀Time is defined as a secondary fault, 0.8k₀＜k_e≤0.95k₀Time is defined as a three-level fault, where k₀The back electromotive force coefficient is the back electromotive force coefficient of the motor in the normal state.

For different fault levels, the processing mode aiming at the fault motor is as follows: when the clutch actuating motor has a primary fault, the power supply for the motor needs to be stopped immediately, and the motor stops working. When the actuating motor of the clutch has a secondary fault, considering that the working time of the fault motor needs to be shortened as much as possible and the fault aggravation is avoided, a control method taking time as an optimal performance index is adopted to decide the separation rule of the clutch with the motor fault, and when the clutch is completely separated, the fault motor stops being used. This effect has been taken into account when designing time-optimal control algorithms, since motor failure can lead to a reduction in clutch actuation motor output torque. To design a time optimal control algorithm for a torque phase stage in a DCT (discrete cosine transformation) gear-shifting process, firstly, power of the torque phase stage in the DCT gear-shifting process needs to be builtLearning a model, and simplifying the built model, wherein the simplified model is as follows:(wherein T is_c1、T_c2For transmitting torque, K, to the clutch₁、K₂Conversion factor, T, for the clutch transfer torque equivalent to the gearbox output shaft_rAs the load torque, omega_sIs the rotational speed of the output shaft of the transmission, c_sIs a damping coefficient, I, equivalent to the output shaft of the transmission_sIs equivalent to the rotational inertia of the output shaft of the transmission), and selects a state variable based on a torque phase dynamic model of a six-speed dry DCT shifting processx₂＝T_c1、x₃＝T_c2Control quantity ofThe principle of 'shock-free gear shifting' is adopted in the torque phase stage, namely:based on the above-mentioned principles and the set state variables, the state equation for the torque phase of the shift process can be derived: the performance indexes of the control algorithm are as follows:range-u of control quantity u_maxU is not more than 0 (wherein u is_maxThe characteristic of the clutch actuating motor and the influence of the fault on the clutch actuating motor are comprehensively considered, and the system co-state vector is (lambda)₁、λ₂、λ₃) The Hamilton function is H1 + lambda₁u((K₁/I_s)-(i₁K₂/i₂K₁))-(c_s/I_s)x₁λ₁+λ₂u-λ₃(i₁/i₂) u, the regular equation isH rate of change is H^*(t_f) With the boundary condition of 0λ₂(t_f) And v, based on the formula, solving a clutch separation rule corresponding to the motor with the 2-stage fault in the torque phase stage in the gear shifting process. The time optimal control algorithm for the inertia phase stage of the DCT gear-shifting process needs to be designed, and a DCT gear-shifting process inertia phase dynamic model needs to be built at first, and the built model is simplified, wherein the simplified model is as follows:(wherein T is_c1For transmitting torque, K, to the clutch₁Conversion factor, T, for the clutch transfer torque equivalent to the gearbox output shaft_rAs the load torque, omega_sIs the rotational speed of the output shaft of the transmission, c_sIs a damping coefficient, I, equivalent to the output shaft of the transmission_sRotational inertia equivalent to the output shaft of the transmission), selecting state variables based on a six-speed dry DCT shift process inertia phase kinetic modelx₂＝T_c1Control quantity ofThe state equation of the system can be deduced by using the dynamic model and the set state variables:the performance indexes of the control algorithm are as follows:range-u of control quantity u_maxU is not more than 0 (wherein u is_maxThe characteristic of the clutch actuating motor and the influence of the fault on the clutch actuating motor are comprehensively considered, and the system co-state vector is (lambda)₁、λ₂) The Hamilton function is H1 + lambda₁K₁(u/I_s)-λ₁(c_s/I_s)x₁+λ₂u, the regular equation isH rate of change is H^*(t_f) With the boundary condition of 0λ₂(t_f) And (v) solving a clutch separation rule corresponding to the motor with the 2-stage fault in the inertia phase stage in the gear shifting process based on the formula. When the three-stage fault occurs in the clutch actuating motor, no treatment is temporarily carried out. The fault-tolerant control method for the clutch actuating motor in the upshifting process of the six-speed dry type dual-clutch automatic transmission designed below is developed based on the processing mode for the fault motor.

As shown in fig. 1, when the DCT vehicle is in stable operation in 1 st gear with 30% accelerator pedal opening, the fault-tolerant control method of single-clutch skip upshift is completed by using the clutch corresponding to the odd-numbered gear when an upshift command is received but the clutch actuator corresponding to the 2 nd gear fails. The fault-tolerant control method aiming at the faults is characterized in that: the method includes the steps that a clutch which corresponds to a gear 1 and does not have motor faults is separated, a separation rule adopts an exponential-like curve, the time required for separation is 420ms, after the clutch which does not have the motor faults is completely separated, a synchronizer is controlled to complete gear disengagement, idle stroke elimination and gear engagement operation (the gear engaged is 3), after gear engagement is completed, the clutch which does not have the motor faults is controlled to be engaged, and meanwhile, the rotating speed of an engine is adjusted to be consistent with the rotating speed of a clutch driven plate which does not have the motor faults. When the rotating speeds of the main driving disc and the auxiliary driving disc of the clutch without the motor fault are synchronous, the clutch without the motor fault is quickly compressed to the maximum displacement, and meanwhile, the engine torque is switched to a value required by a driver, and the single clutch skip gear-up is completed. At 30% pedal opening, the time for a DCT vehicle to skip up-shift from 1 gear to 3 gears is 1.72 s.

Fig. 2 shows a fault-tolerant control method for 1-stage fault of the clutch actuator corresponding to 1-gear during the torque phase stage of 1-gear upshift 2-gear under 30% of accelerator pedal opening. If the clutch actuating motor corresponding to the 1 gear fails to work at the 1 level when the gear shifting process is carried out for 0.357s (in the torque phase stage of the gear shifting process), the power supply of the motor is stopped immediately, because the clutch is a normally open type clutch, after the power supply of the clutch actuating motor is stopped, the clutch corresponding to the 1 gear with the motor failure can be quickly separated, at the moment, in order to ensure that the impact degree of the whole vehicle is minimum, the clutch corresponding to the 2 gear without the motor failure is continuously engaged according to the corrected engagement rule, when the clutch corresponding to the 1 gear with the motor failure is completely disengaged for 75ms, the clutch enters the inertia phase stage, the rotating speed of the engine is adjusted until the rotating speed of the clutch driven disc corresponding to the 2 gear without the motor failure is consistent, in the speed regulating process of the engine, in order to ensure that the impact degree of the whole vehicle is minimum, the torque transmission of the clutch corresponding to the 2 gear needs to be kept unchanged, and after the rotating speed is synchronous, the clutch corresponding to the 2 gear without the The torque is switched to the driver demand and enters 2 nd stable operation, and the time elapsed from the diagnosis of the fault to the entry of 2 nd stable operation is 617 ms.

Fig. 3 shows a fault-tolerant control method for 2-stage failure of the clutch actuator corresponding to the 1-gear during the torque phase of the 1-gear upshift 2-gear process under the 30% accelerator pedal opening. If a 2-level fault occurs when a clutch actuating motor corresponding to the 1-gear goes to 0.357s in the gear shifting process (the torque phase stage in the gear shifting process), considering that the working time of the fault motor is shortened as much as possible and the fault is prevented from being aggravated, the clutch corresponding to the 1-gear with the motor fault is separated according to a separating rule determined by bang-bang control with time as the optimal performance index, at the moment, in order to ensure that the impact degree of the whole vehicle is minimum, the clutch corresponding to the 2-gear without the motor fault is continuously engaged according to a corrected engaging rule, when the clutch with the motor fault is completely disengaged for 91ms, the inertia phase stage is entered, the rotating speed of the engine is adjusted until the rotating speed of a clutch driven disc corresponding to the 2-gear without the motor fault is consistent, and in the speed regulation process of the engine, in order to ensure that the impact degree of the whole vehicle is minimum, the transmitting torque of the clutch corresponding to the 2-gear without, after the rotation speed is synchronized, a clutch corresponding to the 2 nd gear without the motor fault is quickly pressed to the maximum displacement, the engine torque is switched to a value required by a driver, the 2 nd gear stable operation is started, and the elapsed time from the fault diagnosis to the 2 nd gear stable operation is 642 ms.

At the torque phase stage of the 1-gear and 2-gear upshift process under the condition of 30% of accelerator pedal opening, the time for the clutch actuating motor corresponding to the 1-gear to ascend into the 2-gear after 2-gear fault is 25ms longer than the time for the clutch actuating motor to ascend into the 2-gear after 1-gear fault.

Fig. 4 shows the fault-tolerant control of the 1-stage fault of the clutch actuator corresponding to the 2-stage during the torque phase of the 1-stage upshift 2-stage process under the 30% accelerator pedal opening. If the clutch actuating motor corresponding to the 2-gear fails to supply power to the motor at the 1-level when the gear shifting process is carried out for 0.384s (the torque phase stage of the gear shifting process), the power supply to the motor is stopped immediately, because the clutch is a normally open type clutch, after the power supply of the clutch actuating motor is stopped, the clutch corresponding to the 2-gear with the motor failure can be quickly separated, at the moment, in order to ensure the minimum impact degree of the whole vehicle, the separated clutch corresponding to the 1-gear without the motor failure is re-engaged according to the engagement rule in a certain proportional relation with the separation speed of the clutch corresponding to the 2-gear with the motor failure, when the clutch corresponding to the 2-gear with the motor failure is completely disengaged after 104ms, the inertia phase stage is carried out, the rotating speed of the engine is adjusted until the rotating speed of the clutch driven plate corresponding to the 1-gear without the motor failure is consistent, and in the speed adjusting process of the, the transmission torque of the clutch corresponding to the 1 st gear without the motor fault is required to be kept unchanged, the clutch corresponding to the 1 st gear without the motor fault is quickly pressed to the maximum displacement after the rotating speed is synchronized, the engine torque is switched to a driver required value, the 1 st gear stable operation is re-entered, and the time from the diagnosis of the fault to the re-entry of the low-gear stable operation is 298 ms.

Fig. 5 shows the fault-tolerant control method after a 2-stage fault occurs in the clutch actuator corresponding to the 2-stage gear at the torque phase stage of the 1-stage gear-up and 2-stage gear-up process under the condition of 30% of the opening degree of the accelerator pedal. If the clutch actuating motor corresponding to the gear 2 has a 2-level fault when the gear shifting process is carried out for 0.384s (the torque phase stage of the gear shifting process), considering that the working time of the fault motor is shortened as much as possible and the fault is prevented from being aggravated, the clutch corresponding to the gear 2 with the motor fault is separated according to a separation rule determined by bang-bang control with time as the optimal performance index, at the moment, in order to ensure that the impact degree of the whole vehicle is minimum, the separation clutch corresponding to the gear 1 without the motor fault is re-engaged according to an engagement rule in a certain proportional relation with the separation speed of the clutch corresponding to the gear 2 with the motor fault, when the clutch corresponding to the gear 2 with the motor fault is completely disengaged after 125ms, the inertia phase stage is carried out, the rotating speed of the engine is adjusted until the rotating speed of the clutch disc corresponding to the gear 1 without the motor fault is consistent, and in the speed regulating process of the, and in order to ensure the minimum impact degree of the whole vehicle, the transmission torque of the clutch corresponding to the 1 st gear without the motor fault is required to be kept unchanged, the clutch corresponding to the 1 st gear without the motor fault is quickly pressed to the maximum displacement after the rotating speed is synchronized, the engine torque is switched to a required value of a driver, the 1 st gear stable operation is started again, and the time from the diagnosis of the fault to the 1 st gear stable operation is 315 ms.

At the stage of the torque phase of the 1 gear upshift and the 2 gear upshift process under the condition of 30% of the opening degree of an accelerator pedal, the time for returning to the 1 gear after the 2-gear fault of a clutch actuating motor corresponding to the 2 gear is 17ms longer than the time for returning to the 1 gear after the 1-gear fault occurs.

Fig. 6 shows a fault-tolerant control method for a 1-stage fault of a clutch actuator corresponding to a 2-gear during a 1-gear upshift and a 2-gear inertia phase stage under an accelerator opening of 30%. If the clutch actuating motor corresponding to the 2-gear fails at the 1-gear stage when the gear shifting process is carried out for 0.874s (during the inertia phase of the gear shifting process), the power supply for the motor is immediately stopped, because the clutch is a normally open type clutch, after the power supply of the clutch actuating motor is stopped, the clutch corresponding to the 2-gear stage with the motor failure is quickly separated, the clutch corresponding to the 2-gear stage with the motor failure is completely separated after 92ms, the rotating speed of the engine is adjusted until the rotating speed of a clutch driven plate corresponding to the 1-gear stage which is completely separated at the moment without the motor failure is consistent with the rotating speed of a clutch master-slave plate corresponding to the 1-gear stage without the motor failure, after the clutch corresponding to the 2-gear stage with the motor failure is completely separated and the rotating speed of the clutch master-slave plate corresponding to the 1-gear stage without the motor failure is consistent, the clutch corresponding to the 1-gear stage with the motor failure is re-engaged again and is quickly pressed to the maximum displacement, and the, the 1 st gear stable operation was re-entered, and the elapsed time from the diagnosis of the fault to the re-entry of the 1 st gear stable operation was 569 ms.

Fig. 7 shows a fault-tolerant control method for 2-stage failure of the clutch actuator corresponding to the 2-gear during the inertia phase stage of the 1-gear upshift and the 2-gear upshift under the 30% accelerator pedal opening. If the clutch actuating motor corresponding to the gear 2 fails when the gear shifting process reaches 0.874s (during the inertia phase of the gear shifting process), considering that the working time of the failed motor is shortened as much as possible and the failure is prevented from being aggravated, the clutch corresponding to the gear 2 with the motor failure is separated according to the separation rule determined by bang-bang control with time as the optimal performance index, the clutch corresponding to the gear 2 with the motor failure is completely separated after 163ms, the rotating speed of the engine is adjusted until the rotating speed of the clutch driven plate corresponding to the completely separated gear 1 without the motor failure is consistent while the clutch corresponding to the gear 2 with the motor failure is separated, and when the clutch corresponding to the gear 2 with the motor failure is completely separated and the rotating speed of the clutch driven plate corresponding to the gear 1 without the motor failure is consistent, the clutch corresponding to the completely separated gear 1 without the motor failure is re-engaged and is rapidly compacted to the maximum displacement And the engine torque is switched to the driver required value and the 1 st gear stable operation is re-entered, the elapsed time from the diagnosis of the fault to the re-entry of the 1 st gear stable operation is 597 ms.

In the inertia phase stage of the 1 gear-up and 2 gear-up process under the condition of 30% of the opening degree of an accelerator pedal, the time for returning to the 1 gear after the 2-gear fault of a clutch actuating motor corresponding to the 2 gear is 28ms longer than the time for returning to the 1 gear after the 1-gear fault occurs.

The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose of the embodiments is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All modifications made according to the spirit of the main technical scheme of the invention, such as a fault-tolerant control method of a clutch actuating motor in a six-speed dry DCT downshift process, are covered in the protection scope of the invention.

Claims (8)

1. A fault-tolerant control method for the actuating motor of clutch in six-speed dry DCT up-shift procedure is used to carry out fault-tolerant control on the possible faults of the actuating motor of clutch in the stages of torque phase and inertia phase,

the possible fault conditions of the clutch actuating motor comprise:

fault condition 1: when a gear-up instruction is received during stable operation of the gear, the actuating motor of the high-gear clutch breaks down;

and (3) fault working condition 2: the method comprises the following steps that a separation clutch actuating motor breaks down in a torque phase stage in the gear-up process, when the possible fault working condition of the clutch actuating motor is a fault working condition 2, the control action is completed by adopting a corresponding method according to the faults of the separation clutch actuating motor in different grades and aiming at the minimum impact degree of the whole vehicle, and the concrete steps of completing the control action by adopting the corresponding method according to the faults of the separation clutch actuating motor in different grades and aiming at the minimum impact degree of the whole vehicle are as follows:

if the fault grade of the separating clutch actuating motor is 1, immediately stopping power supply of the motor, continuously engaging an engaging clutch without motor fault according to the corrected engaging rule, entering an inertia phase stage after the clutch without motor fault is completely disengaged, adjusting the rotating speed of the engine until the rotating speed of the engine is consistent with the rotating speed of a clutch driven disc without motor fault, keeping the transmission torque of the engaging clutch without motor fault unchanged in the process of engine speed regulation, quickly pressing the clutch without motor fault to the maximum displacement and switching the engine torque to the value required by a driver after the rotating speeds are synchronous, and entering high-gear stable operation;

if the fault grade of the separating clutch actuating motor is 2, separating the clutch with motor fault according to a separating rule determined by bang-bang control with time as the optimal performance index, continuing to engage the engaging clutch without motor fault according to a corrected engaging rule, entering an inertia phase stage after the clutch with motor fault is completely disengaged, adjusting the rotating speed of an engine until the rotating speed of the engine is consistent with the rotating speed of a clutch driven disc without motor fault, keeping the transmitting torque of the engaging clutch without motor fault unchanged in the process of engine speed regulation, quickly compressing the clutch without motor fault to the maximum displacement after the rotating speeds are synchronous, switching the engine torque to a required value of a driver, and entering high-gear stable operation;

if the fault grade of the clutch separating actuating motor is 3, the gear-up is completed by following the originally formulated control method of the torque phase stage in the gear-up process;

and (3) fault working condition: the actuation motor of the clutch is engaged to generate faults in the torque phase stage in the gear-up process;

and (4) fault working condition: and the actuation motor of the engagement clutch fails in the inertia phase stage of the gear-up process.

2. The method for fault-tolerant control of the clutch actuator motor in the six-speed dry DCT upshifting process according to claim 1, wherein when the possible fault condition of the clutch actuator motor is fault condition 1, the single-clutch skip upshift is completed by using the clutch without motor fault.

3. The fault-tolerant control method for the actuation motor of the six-speed dry DCT during the upshift process as recited in claim 2, wherein the single clutch skip upshift specifically comprises the following steps:

the method comprises the steps of firstly separating a clutch corresponding to a low gear without motor faults, controlling a synchronizer to complete gear picking, idle stroke elimination and gear engaging after the clutch without motor faults is completely separated, controlling the clutch without motor faults to be engaged after gear engaging is completed, simultaneously adjusting the rotating speed of an engine to be synchronous with the rotating speed of a clutch driven disc of the clutch without motor faults, compressing the clutch without motor faults to the maximum displacement after the rotating speeds are synchronous, and simultaneously switching the torque of the engine to a value required by a driver to complete gear rising of the single-jump clutch.

4. The fault-tolerant control method for the clutch actuator motor in the six-speed dry DCT upshifting process according to claim 1 is characterized in that when the possible fault condition of the clutch actuator motor is fault condition 3, the control action is completed by adopting a corresponding method according to the different grades of faults of the engaged clutch actuator motor and with the aim of minimizing the impact degree of the whole vehicle.

5. The fault-tolerant control method for the actuation motor of the six-speed dry DCT during the upshift process according to the claim 4, characterized in that the specific steps of completing the control action by adopting the corresponding method with the aim of minimizing the impact degree of the whole vehicle according to the different grades of the faults of the actuation motor of the engaged clutch are as follows:

if the fault grade of the engagement clutch actuating motor is 1, immediately stopping power supply of the motor, re-engaging a separation clutch without motor fault according to an engagement rule in a certain proportional relation with the separation speed of the clutch with motor fault, entering an inertia phase stage after the clutch with motor fault is completely disengaged, adjusting the rotating speed of an engine until the rotating speed of the engine is consistent with the rotating speed of a clutch driven disc which is re-engaged without motor fault, keeping the transmission torque of the clutch which is re-engaged unchanged in the process of speed regulation of the engine, quickly compressing the clutch without motor fault to the maximum displacement and switching the torque of the engine to the required value of a driver after the rotating speeds are synchronous, and re-entering low-gear stable operation;

if the fault grade of the actuating motor of the engaging clutch is 2, the clutch with the motor fault is separated according to a separating rule determined by bang-bang control with time as the optimal performance index, at the moment, in order to ensure that the impact degree of the whole vehicle is minimum, the separating clutch without the motor fault is re-engaged according to an engaging rule in a certain proportional relation with the separating speed of the clutch with the motor fault, when the clutch with motor failure is completely disengaged, the inertia phase stage is entered, the engine speed is adjusted until the engine speed is consistent with the speed of the clutch driven plate which is not engaged again with motor failure, in the process of engine speed regulation, the transmission torque of the clutch which is re-engaged is kept unchanged, after the rotating speed is synchronized, the clutch which does not have motor fault is quickly compressed to the maximum displacement, the engine torque is switched to a value required by a driver, and the engine enters the low-gear stable operation again;

if the fault grade of the engaging clutch actuating motor is 3, the upshift is completed according to the originally established control method of the torque phase stage of the upshift process.

6. The fault-tolerant control method for the clutch actuator motor in the six-speed dry DCT upshifting process according to claim 1 is characterized in that when the possible fault condition of the clutch actuator motor is fault condition 4, the control action is completed by adopting a corresponding method according to the different grades of faults of the engaged clutch actuator motor and with the aim of minimizing the impact degree of the whole vehicle.

7. The fault-tolerant control method for the actuation motor of the six-speed dry DCT during the upshift process according to the claim 6, characterized in that the specific steps of completing the control action by adopting the corresponding method with the aim of minimizing the impact degree of the whole vehicle according to the different grades of the faults of the actuation motor of the engaged clutch are as follows:

if the fault grade of the engaging clutch actuating motor is 1, immediately stopping the power supply of the motor, adjusting the rotating speed of the engine until the rotating speed of the engine is consistent with the rotating speed of a clutch driven disc which does not have motor fault and is completely separated in the process of separating the clutch with the motor fault, after the clutch with the motor fault is completely separated and the rotating speeds of a clutch main driven disc and a clutch driven disc which do not have motor fault are consistent, re-engaging and quickly pressing the clutch which does not have motor fault and is completely separated to the maximum displacement, switching the torque of the engine to the value required by a driver, and re-entering the low-gear stable operation;

if the fault grade of an actuating motor of an engaged clutch is 2, the clutch with the motor fault is separated according to a separation rule obtained by bang-bang control with time as the optimal performance index, in the process of separating the clutch with the motor fault, the rotating speed of an engine is adjusted until the rotating speed of the clutch is consistent with the rotating speed of a clutch driven disc which does not have the motor fault and is completely separated, and after the clutch with the motor fault is completely separated and the rotating speed of a clutch main driven disc which does not have the motor fault is consistent with the rotating speed of the clutch driven disc which does not have the motor fault, the clutch which is completely separated at the moment without the motor fault is re-engaged and quickly pressed to the maximum displacement, the engine torque is switched to the value required by a driver, and the clutch enters;

and if the fault grade of the engaging clutch actuating motor is 3, finishing the gear-up by following the originally established control method of the inertia phase stage of the gear-up process.

8. The fault-tolerant control method for the actuation motor of the six-speed dry DCT during the upshift process according to the claim 5, wherein the engagement rule of the certain proportional relationship is as follows:

wherein,the transfer torque change rate of the off-going clutch where no motor failure has occurred,rate of change of transmission torque of disconnect clutch for motor failure, i₁Transmission ratio of gearbox corresponding to separating clutch without motor fault₂The gear ratio of the gearbox corresponding to the separating clutch with motor failure.