Development And Application Of Electronic Vehicle Controller Unit For A Hybrid Electric City Bus

Energy shortage, oil crisis and environmental pollution become more and more intense, bring great impact on people's lives, and are directly related to national economic and social sustainable development. Therefore, many countries in the world are actively developing new energy technologies. Electric vehicle acts as a kind of new energy vehicles of low oil consumption, low pollution and low noise, and is considered as an important way to solve the energy crisis and environmental degradation. Hybrid electric vehicle takes the advantages of both pure electric vehicle and combustion engine vehicle, effectively improves the fuel economy and emissions, and also meets power requirements and driving range requirements, and is considered as one of the effective ways to energy conservation and emissions reduction.In chapter 2, according to the driving cycle characteristics of the city bus in our country, hybrid electric city bus based on series-type structure is developed.Parameters of key components of powertrain system are matched to meet the targets of power requirements and fuel economy. The whole Vehicle control system network structure and operating principle are studied, communication mechanisms and interactive interfaces between CAN bus nodes based on CAN bus (Controller Area Network) are analyzed. The vehicle running logic state and work steps of control system are studied.In chapter 3, Electronic Vehicle Controller Unit (core control unit) is developed on the basis of HFF6120GSHEV series hybrid electric city bus. Hardware functional requirements and performance requirements of Electronic Vehicle Controller Unit are analyzed in detail to meet the design targets. According to design requirements, design and implementation of a modular circuit is completed, EMC design and design of reliability are completed to meet the requirements of projects and series.In chapter 4, on the basis of Electronic Vehicle Controller Unit hardware circuit, overall design of software is completed to meet the functional requirements. Multiple lower layer drivers are designed with modular design method according to the system resources of Freescale's MPC5534. the applications of Electronic Vehicle Controller Unit is designed to meet the functional requirements, is programmed using the developing software of Codewarrior, and applied to HFF6120GSHEV series hybrid electric city bus. In chapter 5, according to powertrain system solutions of the HFF6120GSHEV series hybrid electric city bus, vehicle simulation software - AVL's cruise is used to simulate its powertrain indicators to verify the feasibility of powertrain systems. At the same time, The cruise software is also used to simulate hybrid electric city bus control strategies of energy distribution and energy recovery, and fuel economy and power influence caused by energy distribution strategy and energy recovery strategy are analyzed to optimize both control strategies. The HFF6120GSHEV series hybrid electric city bus fuel economy Indicator is estimated.In chapter 6, Laboratory tests, experimental tests and road test based on HFF6120GSHEV series hybrid electric city bus are conducted. The results show that the performances of power and fuel economy of HFF6120GSHEV meet the design targets. Many different kinds of tests, such as functional, performance, and long-term stability and reliability, on Electronic Vehicle Controller Unit are conducted. These results also show that the design of Electronic Vehicle Controller Unit is successful.HFF6120GSHEV hybrid electric city bus has good power performance, fuel economy and emissions characteristics, which is proved by experimental tests. At present, Electronic Vehicle Controller Unit is applied to HFF6120GSHEV series hybrid electric city bus and had the failure-free operation over 15,000 Km and achieved fairly good results. Moreover, Electronic Vehicle Controller Unit is versatile and has a wide range of applications.