Environmental Engineering Reference
In-Depth Information
Chapter 3
Hybrid power plant specifications
The vehicle power plant is designed to deliver sufficient propulsion power to the
driven wheels to meet performance targets that are consistent with vehicle brand
image. The previous chapters described how conventional engines and electric
drive systems are matched to meet performance and economy targets. In this
chapter, we continue to evaluate the matching criteria between combustion engines
and ac drives for targeted road load conditions. The reader is no doubt aware of the
various powertrain configurations available in the market place, including small
in-line 3- and 4-cylinder engines with ISA type ac drives matched to the driveline
with 5-, 6- and now 7-speed manual or automatic transmissions or even with con-
tinuously variable transmission engines such as V6 and V8 with inherently higher
torque are typically matched to the driveline with 3- and 4-speed transmissions. At
the high end, V10, V12 and even V16 engines with their available torque ranging
from 350 to nearly 1,400 Nm explain why such drivelines can pull 'tall' gear ratios.
Some examples of this are as follows: the Daimler Chrysler V10 Viper engine is an
aluminium block 8.3 L, overhead valve (OHV), 10-cylinder power plant rated
373 kW (500 PS) and 712 Nm torque. The Jaguar XJ-S V12 is a 5.3 L, 12-cylinder
power plant rated 208 kW (284 PS) with 415 Nm torque at 2,800 rpm. General
Motors Corp. (GM) in January 2003 introduced its Cadillac Sixteen with a V16
aluminium block engine. The 13.6 L, OHV, V16 delivers 746 kW (1,000 PS) and
1,356 Nm of torque at just 2,000 rpm. The XV16 Cadillac engine has a mass of
315 kg and is designed to operate with cylinder deactivation. Cylinder deactivation
means the V16 engine can run on eight or as few as four cylinders delivering an
impressive 20 mpg fuel economy in the 2,270 kg GM flagship vehicle.
In 2009 Chevy introduced the 2010 Camaro SS designed for auto enthusiasts
and performance aficionados (Figure 3.1). It uses the Zeta platform having im-
proved torsional stiffness to house the LS3 6.2 L V8 engine rated 426 hp (318 kW)
and Tremec TR6060 6-speed automatic transmission (Table 3.1).
In the following sections the various trade-offs between power plant torque and
power rating are illustrated in regard to transmission selection and vehicle per-
formance. To further illustrate the process, suppose the power plants described
above are placed into passenger vehicles of size and weight recommended by the
manufacturers. Table 3.2 shows the specifics of the vehicle propulsion system.
Furthermore, because of lack of transmission data, the driveline gearing in low gear
