Development Of Multi-power Powertrain Control System For Series Hybrid Electric Bus Based On DSP

There are two serious problems against the continual development of automotive industry at present. One is environment pollution;the other is deficiency of petroleum resources. Hybrid electric vehicle (HEV) employing two power sources - internal combustion engine (ICE) and electric motor (EM), has been accepted world widely as one of the most promising methods to solve these two problems. Many developed country , governments and automobile manufactures have invested a lot of develop HEVs, HEV components and the key HEV technologies.The paper researches and develops one of the projects, named Multi-Energy Sources Power Assembly Control System, Which is supported by the subjects of a cross-sectional study topic with an enterprise. A power control strategy model for series hybrid electric bus has been set up based on the requisition analysis, the author completed hardware design plan, software design plan and Network design plan systemically.The series hybrid-electricity-bus powertrain control strategy divide the power assembly control to two parts, engine electricity generator control and vehicle moment power flow control, the former way is to arrange fuel engine and electricity generator work along the joint-most-efficiency-curve for setting their work condition (fuel engine oil throttle, rotation speed and generator torque) in a good lever corresponding any generate electricity demand. And the curve comes from a curve fitting by analyze the fuel engine efficiency map and motor efficiency curve. The latter is to finger out how much generate electricity power should be produced by using the city bus database, the whole power assembly can get the best efficiency in a period of future time by control power output from the engine-generator unite.Multi-Energy Sources Power Assembly Control System is based on a type of DSP, TMS320LF2407. according to controller hardware design plan, which takes full advantage of DSP's internal module and spread its' external bus. The author designed the power supply module, A/D module, D/A module, 10 module, CAN communication module and SCI communication module. Lots of anti-jamming measures have been used because of the controller design aimed at high performance and high reliability. These measures can promote DSP controllers' viability in hybrid electricity bus environment. While the software design is based on front-and-back platform, the author program the hybrid electricity bus powertrain control strategy in building block design mode. The software part emphatically introduce the joint control method for controlling the engine-generator unite and a simplyway to compute the SOC of battery. Based on the CAN fieldbus, the paper resolves the communication method of the hybrid power assembly control system. According as the CAN protocol of the American vehicle field, the paper constituted an application layer protocol for Series hybrid bus.In order to prove the viability of the whole design proposal and the control performance of the DSP controller, the author test it on the electric motor bench and in the hybrid bus. All test data show that the hybrid power assembly controller can control the hybrid electric bus effectively and the control strategy is workable.