Research Of Capacitive Hybrid Vehicle Powertrain Control System

The research for Hybrid Electric Vehicle is a long-term technology to reduce environmental pollution and energy consumption.HEV control unit(HCU) is main control componet,for further research on HCU,taking the integrate starter generator (ISG) ultra-capacitance HCU as the research object based on the type of ultra-capacitance single axis parallel HEV, do the research and development of OSEK embedded real-time operating system platform control system based onμC/OS-Ⅱ.The functions and performance requirements of HCU were analyzed based on the ISG ultra-capacitance HEV. After analysing the composition of the electric control system,HCU system scheme and high-performance hardware system on the platform of MC9S12DP512 were confirmed.HCU energy management control strategy was analyzed and researched by the "driver intention recognition-energy management-coordinated control",and the control strategy was divided into ten different priority tasks according to the task partitioning principle in embedded operating system.Embedded real-time multitasks operating system design methods and principles are presented.The features of theμC/OS-Ⅱand OSEK/VDX OS and their differences were analyzed,then a vehicle real-time operating system which matches with ECC1 class,scheduling of tasks and alarms,scheduling of events,handling of shared resources and interrupts in the OSEK/VDX OS. According to the characteristics in hybrid electric vehicle control system,the HCU software system based onμC/OS-Ⅱwas designed by software architecture under the OSEK multi-tasks real time operating system.Then,the control functions in the ISG ultra-capacitance HEV were added to the OSEK multi-tasks real time operating system based onμC/OS-Ⅱ,the accuracy of control strategy is provided.A drum test was done on the prototype HEV, the test indicated that the developed HCU can achieve the steadily control on continuous working conditions and operation mode switching.What's more,the typical conditions such as rapidly starting,transient optimization,energy feedback and idle speed control were tested on the road, the tests show that HCU can control the vehicle following by the predetermined control strategy; The vehicle controlled by HCU can satisfy the economy, dynamic performance and driving smooth requirements of the design scheme.Some advantages of multitasks real-time operating system were reflected by comparative analysing of engine start process dragged by ISG controlled by basic real-time systems and OSEK multi-tasks real time operating system based onμC/OS-Ⅱ.