Study And Realization Of Multi-power Drivetrain Control System For Hybrid Electric Vehicle

One of the major social problems is air pollution and energy shortage. As far as cities are concerned, the single largest remaining contributor to air pollution is the emission of fossil fuel burning transportation vehicles, so many countries regulate rigorous emission restrictions. California in USA has enacted legislation that requires 10% of all vehicles sold in 2003 to be "zero emission vehicle"(ZEV). In practice, ZEV means pure electric vehicle (EV). However, electric vehicles suffer from many disadvantages, such as short distance in continuously driving and high cost, which motivates the development of hybrid electric vehicle (HEV).As a key technology of hybrid electric system, multi-power controller is in charge of distributing demanded motive power to internal combustion engine and electric motor rationally, in order to get high system efficiency, less fuel consumption and low emission. According to the design goals and hybrid electric vehicle system power character, the model and simulation of hybrid electric system is studied as well as software and hardware platform design of multi-power controller, control strategy design and hardware in loop simulation (HILS) of hybrid electric vehicle system.The model and simulation of HEV makes reference to ADVISOR, which is a kind of free software developed by US Department of Energy. Most models of parts are adopted with only parameter changed, except for multi-power controller model, which is rebuilt according to the new control strategy described in the thesis. The new control strategy proves effective and advanced according to the simulation and test result.TMS320LF2407A DSP (Digital Signal Processor) chip is employed in the hardware platform of multi-power controller, which possesses advanced performance and supplies abounding I/O resource and CAN communication widely used in vehicle electric control unit (ECU), so it is fit to real time control of HEV very well. Modularized and Layered architecture is adopted in the controller software. API functions are designed for each layer, which supply convenient service for the upper layer. This kind of software architecture proved good reading, modification and transportation, and control effect is also very good.The control algorithm based on energy flow analysis and HEV state diversion formula distributes demanded motive power adaptively for minimum mean fuel consumption. In each HEV running state, the control strategy is embedded. The vehicle running state shifts smoothly and run stably. The vehicle controlled by the strategy consumes less fuel and emits less emission, and the SOC (State Of Charge) of battery is also controlled well, which proved by the results of simulation and test. Accordingly, the control strategy proved rational and credible.HEV hardware in loop simulation platform supplies a good debugging tool and a convenient test environment for the development of HEV multi-power controller. The HILS platform can help developer find problems of the software and hardware, and reduce the developing period and cost. The test result can be used to evaluate the software and hardware of HEV multi-power controller. It also rebounds to the parameter configuration of HEV power train system and the selection of control strategy.