12.2 Hybrid Vehicle Configurations.............................................................. 363
12.3 Hybrid Vehicle Classification................................................................. 365
12.4 Hybrid Vehicle Operations..................................................................... 367
12.4.1 Series Hybrid Operation ........................................................... 367
12.4.2 Parallel Hybrid Operation ........................................................ 368
12.4.3 Series–Parallel Hybrid Operation............................................ 369
12.4.4 Complex Hybrid Operation...................................................... 371
12.4.5 ISG System Operation ............................................................... 373
12.4.6 ECVT System Operation ........................................................... 376
12.5 Hybrid Vehicle Benefits...........................................................................384
12.5.1 Energy Benefit ............................................................................384
12.5.2 Environmental Benefit .............................................................. 386
12.6 Hybrid Vehicle Trends ............................................................................ 388
Acknowledgments .............................................................................................. 389
References............................................................................................................. 389
12.1 Introduction.............................................................................................. 361
12
Hybrid Vehicles
K. T. Chau
CONTENTS
12.1 Introduction
Electric vehicles (EVs) used to be classified into two groups: the pure EV
that was purely fed by batteries and propelled solely by an electric motor,
and the hybrid EV (HEV) that was sourced by both batteries and liquid fuel
and powered by both the engine and electric motor. With the advent of other
energy sources (Chau, Wong, and Chan 1999), namely fuel cells, ultra capacitors, and ultrahigh-speed flywheels, this classification became ill-suited.
Sometimes, the HEV was even extended to embrace a vehicle using any two
different energy sources such as the battery-ultra capacitor hybrid. In recent
years, there is a consensus that EVs refer to vehicles with at least one of the
propulsion devices being the electric motor. When the energy source is solely
batteries and the propulsion device is only an electric motor, they are termed
the Battery EV (BEV) or sometimes loosely called the EV. When the energy
361
12.3 Hybrid Vehicle Classification................................................................. 365
12.4 Hybrid Vehicle Operations..................................................................... 367
12.4.1 Series Hybrid Operation ........................................................... 367
12.4.2 Parallel Hybrid Operation ........................................................ 368
12.4.3 Series–Parallel Hybrid Operation............................................ 369
12.4.4 Complex Hybrid Operation...................................................... 371
12.4.5 ISG System Operation ............................................................... 373
12.4.6 ECVT System Operation ........................................................... 376
12.5 Hybrid Vehicle Benefits...........................................................................384
12.5.1 Energy Benefit ............................................................................384
12.5.2 Environmental Benefit .............................................................. 386
12.6 Hybrid Vehicle Trends ............................................................................ 388
Acknowledgments .............................................................................................. 389
References............................................................................................................. 389
12.1 Introduction.............................................................................................. 361
12
Hybrid Vehicles
K. T. Chau
CONTENTS
12.1 Introduction
Electric vehicles (EVs) used to be classified into two groups: the pure EV
that was purely fed by batteries and propelled solely by an electric motor,
and the hybrid EV (HEV) that was sourced by both batteries and liquid fuel
and powered by both the engine and electric motor. With the advent of other
energy sources (Chau, Wong, and Chan 1999), namely fuel cells, ultra capacitors, and ultrahigh-speed flywheels, this classification became ill-suited.
Sometimes, the HEV was even extended to embrace a vehicle using any two
different energy sources such as the battery-ultra capacitor hybrid. In recent
years, there is a consensus that EVs refer to vehicles with at least one of the
propulsion devices being the electric motor. When the energy source is solely
batteries and the propulsion device is only an electric motor, they are termed
the Battery EV (BEV) or sometimes loosely called the EV. When the energy
361