Gear shift schedule design for multi-speed pure electric vehicles

Zhu, Bo; Zhang, Nong; Walker, Paul; Zhou, Xingxing; Zhan, Wenzhang; Wei, Yueyuan; Ke, Nanji

doi:10.1177/0954407014521395

Cited by 56 publications

(19 citation statements)

References 4 publications

(6 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…These include (1) geometric and (2) progressive [3]. From these methods it will be possible to determine some available options for the selection of the intermediate ratio of the three speed transmission.…”

Section: Selection Of Intermediate Gear Ratiomentioning

confidence: 99%

“…The gear shift schedule is based on a previous paper [3] that utilizes the mapped efficiency of the electric machine (and transmission if available) to maximize the driving efficiency of the powertrain depending on the selected gear ratio.…”

Section: Selection Of Intermediate Gear Ratiomentioning

confidence: 99%

“…Previous research has investigated the modeling of EV platforms for studying the vehicle performance [1], this has been extended into optimal selection of gear ratios [2] and shift schedule [3], and demonstrate the dependency of the designed vehicle on driving cycle during analysis. This paper builds on this research by expanding the study into evaluation of three speed EVs and the application of these transmissions to alternative vehicle classes.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Comparison of Powertrain System Configurations for Electric Passenger Vehicles

Walker

Roser

Zhang

et al. 2015

SAE Technical Paper Series

Self Cite

View full text Add to dashboard Cite

Electric vehicles (EV) are considered a practical alternative to conventional and hybrid electric passenger vehicles, with higher overall powertrain efficiencies by omitting the internal combustion engine. As a consequence of lower energy density in the battery energy storage as compared to fossil fuels powered vehicles, EVs have limited driving range, leading to a range phobia and limited consumer acceptance. Particularly for larger luxury EVs, electric motors with a single reduction gear typically do not achieve the diverse range of function needs that are present in multi-speed conventional vehicles, most notably acceleration performance and top speed requirements. Subsequently, multi-speed EV powertrains have been suggested for these applications. Through the utilization of multiple gear ratios a more diverse range of functional needs can be realized without increasing the practical size of the electric motor. The major limitation of multi-speed EV powertrains is that the increased transmission complexity introduces additional losses to the vehicle. Through a number of simulations this paper studies the integration of multispeed transmission with EV platforms. Particularly, it investigates the performance improvements of both B and E class vehicle platforms realized through utilization of two and three speed transmissions. Also the potential application of hybrid energy storage systems (i.e. batteries combined with supercapacitors) is studied. Results demonstrate that there can be significant benefits attained for both small and large passenger vehicles through the application of multi-speed transmissions. However, optimization of these ratios must be considered in the analysis.

show abstract

Section: Selection Of Intermediate Gear Ratiomentioning

confidence: 99%

Section: Selection Of Intermediate Gear Ratiomentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Comparison of Powertrain System Configurations for Electric Passenger Vehicles

Walker

Roser

Zhang

et al. 2015

SAE Technical Paper Series

Self Cite

View full text Add to dashboard Cite

show abstract

“…One major flaw in the studied literature is that the gear ratios of the compared layouts have not been optimized for minimum energy consumption [6,12,[15][16][17][18][19][20][21][22]. Thus the results are inconclusive.…”

Section: Introductionmentioning

confidence: 99%

Optimization of multiple transmission layouts for minimal energy consumption of a battery electric vehicle

2018

View full text Add to dashboard Cite

Abstract.Battery electric vehicles (BEVs) are a promising solution for reducing the impacts of passenger vehicles on the environment. However, their driving range is restricted due to the limitations of battery technologies. This range can be extended by adoption of multiple-speed transmissions. Most of the comparisons in the related studies are based on non-optimal designs or limited to modal driving cycles. Furthermore, the impact of power-split continuously variable transmission (PS-CVT) layout with type III power flow on the power consumption of BEVs has never been examined. In this paper, single, two and three-speed transmissions along with PS-CVTs with type I and III power flows are optimized for a case study BEV. Furthermore, the effect of push belt and fulltoroidal CVTs in construction of PS-CVT are compared. The results demonstrate that a PS-CVT with type I power flow equipped with the full-toroidal CVT has the best performance. However, it reduces the energy consumption by 0.36% compared to the optimal two-speed layout. In addition, its ratio range is more limited which can negatively impact the dynamic performance. Finally, simulation of the optimal designs along a different cycle proves that the obtained results are consistent, regardless of the driving cycle.

show abstract

“…Moreover, as the efficiency of an electric drivetrain is a function of torque and speed, a two-speed transmission system increases the flexibility in the selection of the operating region, thus bringing potential energy efficiency benefits [8][9][10][11].…”

Section: Introductionmentioning

confidence: 99%

Energy Consumption of a Battery Electric Vehicle with Infinitely Variable Transmission

et al. 2014

View full text Add to dashboard Cite

Battery electric vehicles (BEVs) represent a possible sustainable solution for personal urban transportation. Presently, the most limiting characteristic of BEVs is their short range, mainly because of battery technology limitations. A proper design and control of the drivetrain, aimed at reducing the power losses and thus increasing BEV range, can contribute to make the electrification of urban transportation a convenient choice. This paper presents a simulation-based comparison of the energy efficiency performance of six drivetrain architectures for BEVs. Although many different drivetrain and transmission architectures have been proposed for BEVs, no literature was found regarding BEVs equipped with infinitely variable transmissions (IVTs). The analyzed drivetrain configurations are: single-(1G) and two-speed (2G) gear drives, half toroidal (HT) and full toroidal (FT) continuously variable transmissions (CVTs), and infinitely variable transmissions (IVTs) with two different types of internal power flow (IVT-I and IVT-II). An off-line procedure for determining the most efficient control action for each drivetrain configuration is proposed, which allows selecting the optimal speed ratio for each operating condition. The energy consumption of the BEVs is simulated along the UDC (Urban Driving Cycle) and Japanese 10-15 driving cycle, with a backward facing approach. In order to achieve the OPEN ACCESSEnergies 2014, 7 8318 lowest energy consumption, a trade-off between high transmission efficiency and flexibility in terms of allowed speed ratios is required.

show abstract

Gear shift schedule design for multi-speed pure electric vehicles

Cited by 56 publications

References 4 publications

Comparison of Powertrain System Configurations for Electric Passenger Vehicles

Comparison of Powertrain System Configurations for Electric Passenger Vehicles

Optimization of multiple transmission layouts for minimal energy consumption of a battery electric vehicle

Energy Consumption of a Battery Electric Vehicle with Infinitely Variable Transmission

Contact Info

Product

Resources

About