Search

A MPC5554-based hybrid control unit (HCU) is developed for a series-parallel hybrid electric bus ( SPHEB) in this paper. Firstly considering the operation features and powertrain configuration of SPHEB with minimizing fuel consumption as objective, a real-time optimal energy management strategy (EMS) based on iterative dynamic programming global optimization algorithm and Elman dynamic neural network is proposed. Then according to the vehicle requirements and EMS, the hardware system of HCU is designed with MPC5554 as CPU. Finally HCU hardware-in-the-loop simulation test is conducted with ETAS PT-LABCAR as platform. The results demonstrate that the developed HCU operates stable and reliable and can effectively realize real-time control for the SPHEB, significantly improving the fuel economy of the vehicle. [ABSTRACT FROM AUTHOR]

In view of the problem of power batteries being frequently charged and discharged at large power in hybrid electric vehicle, the battery/ultra-capacitor hybrid energy storage system (B/UC HESS ) is adopted, which takes advantage of the high power characteristics of ultra-capacitor to improve the performance of storage system. In this paper, two schemes of B/UC HESS are studied: direct battery/ultra-capacitor parallel connection and active battery/ultra-capacitor parallel connection, in which the latter uses DC-DC convertor with zero current transition soft switching as interface to connect battery and ultra-capacitor. The dynamic model for the DC-DC convertor and the models for battery and ultra-capacitor are set up with Matlab simulink and a simulation is conducted with AVL Cruise. The results indicate that the direct parallel scheme doesn't take full use of the capability of ultra-capacitor, while with the active parallel scheme the peak current of battery lowers in pure electric driving and regenerative braking conditions, the variation range of battery end voltage reduces, with an energy efficiency 14. 92 % higher than that of sole battery energy storage system. In addition, its dynamic response performance also improves due to the use of fuzzy PID control algorithm. [ABSTRACT FROM AUTHOR]