Abstract
Multispeed transmissions can enhance the dynamics and economic performance of electric vehicles (EVs), but the coordinated control of the drive motor and gear shift mechanism during gear shifting is still a difficult challenge because gear shifting may cause discomfort to the occupants. To improve the swiftness of gear shifting, this paper proposes a coordinated shift control method based on the dynamic tooth alignment (DTA) algorithm for nonsynchronizer automated mechanical transmissions (NSAMTs) of EVs. After the speed difference between the sleeve (SL) and target dog gear is reduced to a certain value by speed synchronization, angle synchronization is adopted to synchronize the SL quickly to the target tooth slot’s angular position predicted by the DTA. A two-speed planetary NSAMT is taken as an example to carry out comparative simulations and bench experiments. Results show that gear shifting duration and maximum jerk are reduced under the shift control with the proposed method, which proves the effectiveness of the proposed coordinated shift control method with DTA.
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Abbreviations
- AMT:
-
Automated mechanical transmission
- CLAMT:
-
Clutchless automated mechanical transmission
- DG:
-
Dog gear
- DG1:
-
Dog gear of the first gear
- DG2:
-
Dog gear of the second gear
- DM:
-
Drive motor
- DTA:
-
Dynamic tooth alignment
- EV:
-
Electric vehicle
- LM:
-
Load motor
- NSAMT:
-
Nonsynchronizer automated mechanical transmission
- PC:
-
Planet carrier
- PID:
-
Proportion integration differentiation
- PLCD:
-
Permanent linear contactless displacement
- PMSM:
-
Permanent magnet synchronous motor
- RG:
-
Ring gear
- SG:
-
Sun gear
- SL:
-
Sleeve
- A car :
-
Frontal area of vehicle, m2
- A :
-
Coefficient matrix of the state vector
- A d :
-
Discretization matrix of A
- B u :
-
Coefficient matrix of the input vector
- B ud :
-
Discretization matrix of Bu
- B w :
-
Coefficient matrix of the disturbance vector
- B wd :
-
Discretization matrix of Bw
- c c :
-
Viscous damping coefficient of the planet carrier, N·m·(rad/s)−1
- c p :
-
Viscous damping coefficient of the planet gear, N·m·(rad/s)−1
- c r :
-
Viscous damping coefficient of the ring gear, N·m·(rad/s)−1
- c s :
-
Viscous damping coefficient of the sun gear, N·m·(rad/s)−1
- c slv :
-
Viscous damping coefficient during the axial movement of the sleeve, N·(m/s)−1
- C d :
-
Aerodynamic drag coefficient
- C :
-
Damping matrix
- C ςi :
-
Feature matrix of the ith gear
- C ς1 :
-
Feature matrix of the first gear
- C ς2 :
-
Feature matrix of the second gear
- f :
-
Coefficient of rolling resistance
- f floor (·):
-
Downward rounding function
- f ceil(·):
-
Upward rounding function
- F sftmax :
-
Maximum shift force, N
- F slv :
-
Axial combined force exerted on the sleeve
- g :
-
Gravity coefficient, m/s2
- G cur :
-
Current gear
- G P :
-
Gear phase
- G tgt :
-
Target gear
- h ca :
-
Distance between the tooth tip of the sleeve and the tooth tip of the dog gear in the neutral gear, m
- h dog :
-
Tooth height of the dog gear, m
- h fd :
-
Axial distance between the tooth tip of the dog gear and the maximum-width place of its tooth, m
- H L :
-
Distance between point B and the tooth tip of SL in the neutral gear, m
- i 0 :
-
Final ratio
- i tgt :
-
Ratio of the target gear
- j :
-
Vehicle jerk, m/s3
- J ce :
-
Inertia of the planet carrier, kg·m2
- J p :
-
Inertia of planet gear, kg·m2
- J re :
-
Inertia of the ring gear, kg·m2
- J se :
-
Inertia of the sun gear, kg·m2
- J :
-
Inertia matrix
- k :
-
Discrete time
- k en :
-
Time of starting engagement
- l o :
-
Past trajectory of point A2
- l 1 :
-
Original estimated trajectory of point A2
- l 2 :
-
New estimated trajectory of point A2 after adjustment
- m car :
-
Vehicle mass, kg
- m slv :
-
Mass of the sleeve, kg
- N :
-
Number of planetary gears
- n :
-
Rotation speed, r/min
- n s :
-
Rotation speed of the sun gear, r/min
- n r :
-
Rotation speed of the ring gear, r/min
- n c :
-
Rotation speed of the planet carrier, r/min
- R w :
-
Wheel rolling radius, m
- t :
-
Continuous time, s
- t AB :
-
Time of the process from point A to point B, s
- T c :
-
External torques of the planet carrier, N·m
- T end :
-
Torque output of the drive motor at the end of the gear shifting, N·m
- T LM :
-
Torque output of the load motor, N·m
- T m :
-
Torque output of the drive motor, N·m
- T max :
-
Maximum torque of the drive motor in full speed range, N·m
- T mmax :
-
Maximum torque of the drive motor with the current speed, N·m
- T mp :
-
Average torque of the drive motor, N·m
- T mref :
-
Reference torque of the drive motor, N·m
- T r :
-
External torques of the ring gear, N·m
- T s :
-
External torques of the sun gear, N·m
- u a :
-
Vehicle velocity, km/h
- u :
-
Input vector of the system
- v :
-
Vehicle velocity, m/s
- v slv :
-
Axial moving speed of the sleeve, m/s
- w :
-
Disturbance vector of the system
- W dog :
-
Maximum tooth width of the dog gear, m
- x :
-
State vector of the system
- x slv :
-
Axial moving displacement of the sleeve, m
- x slvref :
-
Reference displacement of the sleeve, m
- x slv,A :
-
Axial moving displacement of the sleeve at point A, m
- x slv,B :
-
Axial moving displacement of the sleeve at point B, m
- y ς :
-
Output vector of the system
- Z dog :
-
Number of teeth of the dog gear
- α :
-
Road slope, rad
- β dog :
-
Tooth face chamfer angle of the dog gear, (°)
- γ dog :
-
Tooth side chamfer angle of the dog gear, (°)
- δ car :
-
Inertia coefficient of vehicle
- δx slv :
-
Change of xslv in a sampling period, m
- δω Δ :
-
Change of Δω in a sampling period, rad/s
- δθ Δ :
-
Change of Δθ in a sampling period, rad
- θDG2:
-
Rotation angle of the dog gear of the second gear, rad
- θdog:
-
Rotation angle corresponding to one tooth pitch of the target dog gear, rad
- θ r :
-
Rotation angle of the ring gear, rad
- θ s :
-
Rotation angle of the sun gear, rad
- θslv:
-
Rotation angle of the sleeve, rad
- θ Δd :
-
Dynamic-predicted target angle difference between the sleeve and the target dog gear, rad
- τ :
-
Correction factor of predicted torque
- λ :
-
Characteristic parameter of the planetary mechanism
- χ :
-
Time scaling coefficient
- ω :
-
Rotation speed, rad/s
- ω end :
-
Speed of the drive motor at the end of the gear shifting, rad/s
- ω m :
-
Speed of the drive motor, rad/s
- ω s :
-
Rotation speed of the sun gear, rad/s
- ω r :
-
Rotation speed of the ring gear, rad/s
- ω c :
-
Rotation speed of the planet carrier, rad/s
- Δn :
-
Rotation speed difference between the sleeve and the target dog gear, rpm
- Δω :
-
Rotation speed difference between the sleeve and the target dog gear, rad/s
- Δω ref :
-
Reference rotation speed difference between the sleeve and the target dog gear, rad/s
- Δθ :
-
Rotation angle difference between the sleeve and the target dog gear, rad
- Δθ ref :
-
Reference rotation angle difference between the sleeve and the target dog gear, rad
- Δθ EP :
-
Angle threshold of the engagement point, rad
- Δθ Σ :
-
Total change of the rotation angle difference, rad
References
Ahssan M R, Ektesabi M M, Gorji S A. Electric vehicle with multi-speed transmission: a review on performances and complexities. SAE International Journal of Alternative Powertrains, 2018, 7(2): 169–181
Roozegar M, Angeles J. A two-phase control algorithm for gear-shifting in a novel multi-speed transmission for electric vehicles. Mechanical Systems and Signal Processing, 2018, 104: 145–154
Tian Y, Ruan J G, Zhang N, et al. Modelling and control of a novel two-speed transmission for electric vehicles. Mechanism and Machine Theory, 2018, 127: 13–32
Fietkau P, Kistner B, Munier J. Virtual powertrain development. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 2020, 234(14): 3288–3301
Wang W C, Li J Q, Sun F C. Pseudo-spectral optimisation of smooth shift control strategy for a two-speed transmission for electric vehicles. Vehicle System Dynamics, 2020, 58(4): 604–629
Kim S J, Song C, Kim K S, et al. Analysis of the shifting behavior of a novel clutchless geared smart transmission. International Journal of Automotive Technology, 2014, 15(1): 125–134
Li L, He K, Wang X Y, et al. Sensor fault-tolerant control for gear-shifting engaging process of automated manual transmission. Mechanical Systems and Signal Processing, 2018, 99: 790–804
Yang Y, Wang J S. Synchronous control strategy for electric vehicle based on no clutch shifting. In: Proceedings of the International Conference on Electric Information and Control Engineering. Wuhan: IEEE, 2011, 778–781
Sun Z Q, Sanada K, Gao B Z, et al. Improved decoupling control for a powershift automatic mechanical transmission employing a model-based PID parameter autotuning method. Actuators, 2020, 9(3): 54
Alizadeh H V, Helwa M K, Boulet B. Constrained control of the synchromesh operating state in an electric vehicle’s clutchless automated manual transmission. In: Proceedings of the IEEE Conference on Control Applications. Nice: IEEE, 2014, 623–628
Tseng C Y, Yu C H. Advanced shifting control of synchronizer mechanisms for clutchless automatic manual transmission in an electric vehicle. Mechanism and Machine Theory, 2015, 84: 37–56
Dong X Y, Xi J Q, Chen H Y. The power system active-synchronizing control of the PHEV during the AMT shifting process. Applied Mechanics and Materials, 2011, 80–81: 1155–1159
Mo W W, Wu J L, Walker P D, et al. Shift characteristics of a bilateral Harpoon-shift synchronizer for electric vehicles equipped with clutchless AMTs. Mechanical Systems and Signal Processing, 2021, 148: 107166
Mo W W, Walker P D, Zhang N. Dynamic analysis and control for an electric vehicle with harpoon-shift synchronizer. Mechanism and Machine Theory, 2019, 133: 750–766
Liu H B, Lei Y L, Li Z J, et al. Gear-shift strategy for a clutchless automated manual transmission in battery electric vehicles. SAE International Journal of Commercial Vehicles, 2012, 5(1): 57–62
Alowayed A, Fernandes D, Jeunehomme E, et al. Design of an electric motor transmission system without friction synchronization. In: Proceedings of the International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. Anaheim: ASME, 2019, 1–10
Wang X Y, Li L, He K, et al. Dual-loop self-learning fuzzy control for AMT gear engagement: design and experiment. IEEE Transactions on Fuzzy Systems, 2018, 26(4): 1813–1822
Zhang J W, Chai B B, Lu X Y. Active oscillation control of electric vehicles with two-speed transmission considering nonlinear backlash. Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics, 2020, 234(1): 116–133
Huang W, Zhang J L, Huang J F, et al. Optimal speed regulation control of the hybrid dual clutch transmission shift process. World Electric Vehicle Journal, 2020, 11(1): 11
Zhu X Y, Zhang H, Xi J Q, et al. Optimal speed synchronization control for clutchless AMT systems in electric vehicles with preview actions. In: Proceedings of the American Control Conference. Portland: IEEE; 2014, 4611–4616
Zhu X Y, Zhang H, Fang Z D. Speed synchronization control for integrated automotive motor-transmission powertrain system with random delays. Mechanical Systems and Signal Processing, 2015, 64–65: 46–57
Chen Z Q, Zhang B J, Zhang N, et al. Optimal preview position control for shifting actuators of automated manual transmission. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 2019, 233(2): 440–452
Chen H X, Tian G Y. Modeling and analysis of engaging process of automated mechanical transmissions. Multibody System Dynamics, 2016, 37(4): 345–369
Tian F, Wang L J, Sui L Q, et al. Active synchronizing control of transmission shifting without a synchronizer for electric vehicles. Journal of Tsinghua University (Science and Technology), 2020, 60(2): 101–108
Setiawan Y D, Roozegar M, Zou T, et al. A mathematical model of multispeed transmissions in electric vehicles in the presence of gear shifting. IEEE Transactions on Vehicular Technology, 2018, 67(1): 397–408
Mousavi M S R, Pakniyat A, Helwa M K, et al. Observer-based backstepping controller design for gear shift control of a seamless clutchless two-speed transmission for electric vehicles. In: Proceedings of the 12th IEEE Vehicle Power and Propulsion Conference (VPPC). Montreal: IEEE, 2015
Chaari F, Abbes M S, Rueda F V, et al. Analysis of planetary gear transmission in non-stationary operations. Frontiers of Mechanical Engineering, 2013, 8(1): 88–94
Tian Y, Yang H T, Mo W W, et al. Optimal coordinating gearshift control of a two-speed transmission for battery electric vehicles. Mechanical Systems and Signal Processing, 2020, 136(1): 106521
Tian Y, Zhang N, Zhou S L, et al. Model and gear shifting control of a novel two-speed transmission for battery electric vehicles. Mechanism and Machine Theory, 2020, 152(2): 103902
Walker P, Zhu B, Zhang N. Powertrain dynamics and control of a two speed dual clutch transmission for electric vehicles. Mechanical Systems and Signal Processing, 2017, 85: 1–15
Roozegar M, Angeles J. Gear-shifting in a novel modular multispeed transmission for electric vehicles using linear quadratic integral control. Mechanism and Machine Theory, 2018, 128: 359–367
Fang S N, Song J, Song H J, et al. Design and control of a novel two-speed uninterrupted mechanical transmission for electric vehicles. Mechanical Systems and Signal Processing, 2016, 75: 473–493
Acknowledgements
This work was supported by the Science and Technology Planning Project of Guangdong Province, China (Grant Nos. 2015B010119002 and 2016B010132001).
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Xu, X., Luo, Y. & Hao, X. Coordinated shift control of nonsynchronizer transmission for electric vehicles based on dynamic tooth alignment. Front. Mech. Eng. 16, 887–900 (2021). https://doi.org/10.1007/s11465-021-0653-3
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DOI: https://doi.org/10.1007/s11465-021-0653-3