Next Article in Journal
A Consideration on Maximum Efficiency of Resonant Circuit of Inductive Power Transfer System with Soft-Switching Operation
Previous Article in Journal
Automated Longitudinal Control Based on Nonlinear Recursive B-Spline Approximation for Battery Electric Vehicles
Open AccessArticle

Modeling and Optimal Shift Control of a Planetary Two-Speed Transmission

School of Mechanical Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China
*
Author to whom correspondence should be addressed.
World Electr. Veh. J. 2019, 10(3), 53; https://doi.org/10.3390/wevj10030053
Received: 6 August 2019 / Revised: 2 September 2019 / Accepted: 6 September 2019 / Published: 9 September 2019
To improve the efficiency of electric vehicles (EVs), a planetary two-speed transmission is proposed, which consists of a brushless direct current (BLDC) motor, a turbo-worm reducer, two multi-disc wet brakes, and a Simpson planetary gearset. Based on the devised electronic actuator for shifting, the rotation direction of the BLDC shaft determines the gear ratio of the transmission. For acquiring smooth shift, the state-space equations with control variables of transmission are derived, and a three-stage algorithm is suggested. During the brake engagement process, the optimal control strategy has been developed using linear quadratic regulator control, considering the jerk and friction work of the brake. The simulation results show that the proposed optimal control strategy could reduce the slipping friction work of the brake and improve the shifting quality of EVs. The optimal control trajectory of the BLDC motor was conducted on the electronic shifting actuator bench test. View Full-Text
Keywords: electric vehicle; gear shifting; optimization; two-speed transmission; optimal quadratic control electric vehicle; gear shifting; optimization; two-speed transmission; optimal quadratic control
Show Figures

Figure 1

MDPI and ACS Style

Zhao, X.; Tang, J. Modeling and Optimal Shift Control of a Planetary Two-Speed Transmission. World Electr. Veh. J. 2019, 10, 53.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop