A high-speed motor in a drive system causes several challenges to the reliability of the mechanical parts of electric vehicles and leads to issues with noise,vibration and harshness(NVH).Thus,a two-speed powershift tr...A high-speed motor in a drive system causes several challenges to the reliability of the mechanical parts of electric vehicles and leads to issues with noise,vibration and harshness(NVH).Thus,a two-speed powershift transmission is considered an effective way to improve the dynamic,economic and comfort performance of electric vehicles.A newly designed dual-pump hydraulic control system for a two-speed powershift transmission with two wet clutches is presented,in which the mechani-cal oil pump is linearly affected by the vehicle speed and the electric oil pump is controllable.By integrating the dynamic model of the hydraulic system into one of the powertrains with a two-speed transmission,a co-simulation dynamic model is proposed.To satisfy the flow and pressure demand of the hydraulic system,a dual-pump control strategy is presented,in which the electric oil pump is controlled by the mechanical oil pump following the minimum energy consumption principle.The World Light Vehicle Test Procedure(WLTP)cycle simulation results show that the energy consumption of the proposed hydraulic system can be reduced by 58.2%compared to the previous single-pump system developed by the authors with a constant main-line pressure control strategy.On the basis,the best configuration of the two pumps can further reduce the energy consumption of the hydraulic system by 23.2%compared to that of two-oil pumps with preset displacement.展开更多
基金This work is financially supported by National Natural Science Foundation of China(Grant Number:52072018)Key Science and Technology Innovation Project of Shandong Province(Grant Number:2020CXG011004)+1 种基金2025 Science and Technology Innovation Program of Ningbo(Grant Number:2020Z026)The authors also acknowledge the support of Beijing Key Laboratory for High-efficient Power Transmission and System Control of New Energy Resource Vehicle and the support of the Fundamental Research Funds for the Central Universities。
文摘A high-speed motor in a drive system causes several challenges to the reliability of the mechanical parts of electric vehicles and leads to issues with noise,vibration and harshness(NVH).Thus,a two-speed powershift transmission is considered an effective way to improve the dynamic,economic and comfort performance of electric vehicles.A newly designed dual-pump hydraulic control system for a two-speed powershift transmission with two wet clutches is presented,in which the mechani-cal oil pump is linearly affected by the vehicle speed and the electric oil pump is controllable.By integrating the dynamic model of the hydraulic system into one of the powertrains with a two-speed transmission,a co-simulation dynamic model is proposed.To satisfy the flow and pressure demand of the hydraulic system,a dual-pump control strategy is presented,in which the electric oil pump is controlled by the mechanical oil pump following the minimum energy consumption principle.The World Light Vehicle Test Procedure(WLTP)cycle simulation results show that the energy consumption of the proposed hydraulic system can be reduced by 58.2%compared to the previous single-pump system developed by the authors with a constant main-line pressure control strategy.On the basis,the best configuration of the two pumps can further reduce the energy consumption of the hydraulic system by 23.2%compared to that of two-oil pumps with preset displacement.
