Abstract
Hybrid Electric Vehicle (HEV) coordinates two kinds of power systems: internal combustion engine (ICE) and electric motor. It has both ICE vehicles characteristics of long range and convenient fuel supply and the Electric Vehicle (EV)s characteristics of high efficiency and low exhaust emission. Therefore it has become the popular R&D project in current automobile field.
The configuration of HEV is developing very quickly, especially that of PHEV (Parallel Hybrid Electric Vehicle) and SPHEV(Series and Parallel Hybrid Electric Vehicle). The configurations of different kinds of basic PHEV (Driving Powers of ICE and Electric Motor is Coupled behind Clutch), ISA (Integrated Starter and Alternator) HEV, two types of SPHEV (TOYATO Prius and GM Precept Hybrid) are analyzed and compared systematically based on energy flow of powertrain.
The control strategy of HEV powertrain system is the logical criterion of system working state changing for optimizing the system performance based on the characteristics of system components. The emphasis is the control strategy coordinating the ICE and electric motor.
The effects of different control strategies (different Baseline and Adaptive control strategies) and driving cycles (FTP, ECE+EUDC, HWFET, US06) to the energy economy and exhaust emission performance of a conceptual PHEV are analyzed by simulation.
ISA configuration is adopted in several representative HEVs (Honda Insight, DaimlerChrysler Dodge ESX 3, FORD P2000 Prodigy Hybrid). The configuration and control strategy of ISA are not the same as that of basic HEV.
The above differences are compared and analyzed.
Based on simulation and analyzing it can be found that control strategy and driving cycles greatly affect the vehicle performance with a given vehicle configuration and system module. The result is mainly caused by the instinctive characteristics of the ICE. Different working points of ICE have different efficiency and emission performance. The working points based on different control strategy and different cycles are different. The differences between basic HEV and ISA HEV are resulted from the difference of hybridization and control strategy.