Hybrid Special Vehicles With All-digital Brushless Motor Control

Hybrid electric vehicle (HEV) has motor and gas engine drive. HEV is practical and exigent vehicle owing to its predominant performance, small exhaust gas and pollution. HEV could also be used for special purpose, such as for cover-up when driving by motor engine, or as field electric vehicle when driving by electrical engine. The HEV fix two drive systems in smaller space. Motor drive system is required to not only possess small volume and light weight, but also achieve performance of electromotor and generator. Especially when the HEV applies the brake, in order to energize the storage battery, it is expected that voltage brought by generator is higher than voltage of the storage battery even if speed of generator is slower. At present, this is a new question for discussion and challenge to the HEV.Brushless direct current motor drive system based on DSP in the HEV is researched by complete digital control manner in the paper. Integrating electromotor and generator, a rare earth permanent magnet brushless direct current motor (REPM BLDCM) control system based on DSP in the HEV is studied. The software control thought achieving performance of electromotor and generator is given on condition that the hardware of control circuit is not changed. It is realized that voltage brought by generator is higher than voltage of the storage battery even though speed of generator is slower. The overall project design, hardware and software design of the control system are presented particularly. The design scheme of the paper is tested and the sample has been manufactured. The satisfactory result is shown by the prototype trials.Finally, shortage in project research is analyzed and suggestion is given.