Zhuoping Yu

Vehicle starting control of wet-clutch for Continuously Variable Transmission

Starting control takes an important role in the CVT system, wet clutch control is the key of it. The simplified dynamic model and the influential factors of the clutch during starting process have been introduced in this paper, based on which two control methods: linear pressure control method and fuzzy control method are introduced, and combined with the real vehicle test, two control methods were applied on the test vehicle, and by analyzing and comparing the starting performance after the test, the conclusion is that fuzzy control is more suitable to reflect drivers intention, and it can realize smooth starting in all kinds of working conditions.

Modelica based modeling of automotive transmission

We propose an approach for modeling automotive transmission system using Modelica language. This approach includes dynamic models of clutch and synchronizer, and definition of a system structure for vehicle modeling. This approach enables building of detailed models of a complicated system more easily, and reusing models for different projects. A hybrid transmission is constructed using the approach proposed, and is integrated into the structurized vehicle model. This hybrid vehicle is validated in a virtual NEDC experiment.

Shifting Control of a Novel Active Transmission for Hybrid Vehicle without the Use of Clutch

ICE speed adjustment problem, which is encountered during gear shift process without disengaging clutch under traditional AMT, was introduced. Working principle and structure of a novel fixed axis gear active transmission were described, by which EM couples with the input (HEV-SI) and output shaft (HEV-SO) selectively by automatic switch actuator. Under the former mode, EM can work efficiently by using the gear ratios properly and help ICE to decrease its speed effectively during gear shift process without disengaging clutch. Simulation results validate feasibility of the control algorithm.

Design and experiment of Electro-Hydraulic Brake system

Combined with the analysis on the traditional brake system, the topological structure of the EHB(Electro-Hydraulic Brake) system is summarized. Based on that, one EHB system with motor-reducer mechanism as active power supply is put forward. In this system, one decoupling cylinder is designed to decouple brake pedal and active power supply. The backup mode is also considered in case of motor failure. Selection and design of power supply is completed. Feasibility of this system is validated through simulation and experiment.