Zechang Sun

Performance and characteristic research in LiFePO4 battery for electric vehicle applications

LiFePO4 battery is tested in the research. The capacity, DCR, OCV are evaluated at different ambient temperature. The voltage hysteresis test is conducted by using the simulated current profiles from a HEV models. The result is discussed with some recommendation on the application of this battery in the electric vehicle. component

A Fuzzy Logic Based Regenerative Braking Regulation For a Fuel Cell Bus

For a fuel cell bus, it is significant to equip the regenerative break system to enhance the fuel economy. A two-input, one-output Mamdanis fuzzy inference system is introduced to the regenerative braking model. Taking the safety working conditions of the batteries, the driving dynamics and the occupant comfort into consideration, the method can not only recycle the bus braking energy adequately, but also be adjusted easily according to the practical requirement. Through vehicle tests, the method proves to be a valid solution.

Research on FlexRay communication system

FlexRay is a next-generation automotive control and communication protocol intended for safety-critical automotive applications such as Steering-by-Wire (SBW) system, where electronic connections will replace the mechanical linkages between the steer wheel and the road wheel. A Steering-by-Wire system is introduced, in which a FlexRay control and communication network is setup. According to the requirement of SBW, there are three FlexRay nodes are created. For control and communication purpose, a protocol for communication cluster is developed, the parameters such as signal characteristic, slot, communication time schedule and cycle etc. are defined in the protocol. A SBW FlexRay network simulation system is built by CANoe.FlexRay, which is a powerful simulation environment for FlexRay communication cluster. The network topology, communication messages, control parameters are configurable in the simulation system. The simulation result shows that the SBW system is an efficient communication system. The hardware and the software of the FlexRay nodes are developed respectively, all these nodes are connected as a physical FlexRay cluster. All of the communication messages running in the network are analyzed in detail. The test result indicates it is a reliable control and communication cluster for Steering-by-Wire system.

Assessment of power consumption control strategy for battery management system using hardware-in-the-loop simulation

Based on a self-designed battery management system (BMS), four different working modes with different power consumption levels are set according to driving conditions of hybrid electric vehicle. A power consumption control strategy including the communication rules between vehicle management system (VMS) and battery management system (BMS) is created to make BMS switch reasonably and reliably among different working modes so as to realize as low power consumption as possible. Especially, to validate the feasibility, reliability and necessity of the strategy, hardware in the loop (HIL) simulation is introduced. Also some abnormal events are simulated or fabricated during HIL simulation process to test the performance of the control strategy. After the HIL simulation, the power consumption and whole work consumption integral of BMS is evaluated and assessed.

Controller area network development for a Fuel Cell Vehicle

FCV (Fuel Cell Vehicle) is a new direction for the development of the clean energy vehicle. Nowadays network plays an important role in vehicles, and FCV is also no exception. Compared to the traditional vehicles, there are much more electronic components assembled in FCV. As a result, the electromagnetic environment in FCV is worse then the traditional ones. So the design of the network is crucial.

The research of powertrain for supercapacitor-based series hybrid Bus

Based on the characters of city bus, series hybrid powertrain featuring dasiaAuxiliary Power Unit (APU) + Super capacitor (SC)psila is recommended. With the proposed powertrain configuration, this paper develops a dual-power system for hybrid city bus. The constitution, working principle and relevant control strategies of the system are introduced in details. A novel dual-power structural system was synthesized with gear-box as integrative mechanical design to improve dynamic performance relating to maximum speed, acceleration, climbing etc. Examples of experimental data based on the dynamometer platform under the given urban cycle condition and actual road testing are illustrated. The results show the on-off control strategy is feasible and the adopted powertrain of this hybrid city bus can meet the design target and requirement.

Research On CAN controller conformance test system

Controller Area Network (CAN) is one of the most popular field buses applied in vehicle. For the CAN modules in one vehicle could come from different suppliers, the interoperability of them becomes a question. Though there is a common standard to guide the module design and production, different manufactures could have different interpretations. So a common conformance test is needed before the modules equipped in the vehicle to ensure their design meet the standard requirements and capability to work together. A CAN module is usually composed of three parts: the MCU, the CAN controller and the CAN transceiver. The controller is the main part to realize the CAN communication mechanism. According to ISO 9646, the protocol test should use a hierarchical structure, so a complete CAN conformance test may deal with three layers in OSI reference module. Each layer should be tested separately. In a CAN module, the controller implements the most tasks on DLL (Data Link Layer). Thus, the conformance test on DLL layer of CAN is mainly test the CAN controller. This paper especially focuses on the CAN controller conformance test, which is designed to a hierarchical and black-box test. The test method and test cases are introduced at first. Then a CAN controller conformance test system is designed. The main structure and the test procedure are also described. A single elementary test is also shown up at last to give a more intuitive feeling.

Fault diagnosis systems development for Fuel Cell Vehicle

A hydrogen-powered fuel cell vehicle is developed, in which a distributed control and communication system based on CAN (Controller Area Network) is built. For vehicle diagnostic purpose, a new on-board fault diagnosis strategy is presented. There are two efficient automotive diagnostic systems based on CAN designed and implemented in this paper: (1)CANoe is a powerful CAN development tool. A fault diagnosis environment based on CANoe is established to satisfy the needs of on-board and off-board fault diagnosis application of FCV. By setting up the communication interface between CANoe and Access, the vehicle fault codes are collected and stored. Meanwhile a database is designed for the management of fault information. (2) A hand-held fault diagnosis equipment as well as a windows analyzer interface is set up. All fault information from FCVpsilas CAN network can be gotten easily by the equipment. With the Serial Communication between the equipment and PC, the fault codes stored in the equipment can be read, analyzed and disposed by PC.

The analysis of the factors impacting energy feedback efficiency of fuel cell vehicles

In this paper our research mainly focuses on the energy feedback efficiency of the new energy vehicle through the index for complete vehicle and the relevant parameters of vehicle powertrain. All the word is based on the detailed analysis of the data of vehicles practical operation and the research object is the fuel cell vehicle from Tongji University and Shanghai Fuel Cell Vehicle Powertrain Co., Ltd. (SFCV). Through the analysis and calculation, we obtain the values of the feedback efficiency under different running conditions and the key factors impacting the energy feedback efficiency of fuel cell vehicle. By adjusting these key factors, we analyze the variation tendency of the feedback efficiency and come to some conclusion.

EMC study and testing of the vehicle management system in Clean Energy Automotive

Today, electromagnetic compatibility seems to be one of the major constraints of powertrain and especially for clean energy automotive. The major purpose of paper is to get the veracity and repeatability of the testing results, and then to study the theory of RFI/EMI to resolve the interference resource and cut the interfering path. This paper will carry on the theory analysis and design analysis and EMC study aiming at the vehicle management system, at the same time introduce five imperative EMC tests of automotive components in details and analyse the measured results.