Power-train technologies

Figure 7.1 Candidate fuels and power-train technologies for road vehicles. (Courtesy of the University of Queensland).

Growing global concern about environmental problems caused by the intensive use of fossil fuels for road transport, as well as their limited availability, has triggered a large research and development effort for more efHcient and cleaner power train technologies in order to reduce emissions from the transport sector, which account for about 26% of the energy consumption and CO2 emissions worldwide [21]. 

AppHcation of combined heat and power systems (CHP) Condensate systems integration Boiler personnel training Technology transfer... 

The most attractive feature of the fuel cell technology is probably its superior energy efficiency as a part of a hydrogen-fuel cell-electro-motor power-train, that is, in the tank-to-wheel (TtW) part of the fuel chain. On the other hand, the energy loss in hydrogen production, that is, in the well-to-tank (WtT) part of the fuel chain, is considerable. The total well-to-wheel (WtW) efficiency is potentially superior to even advanced ICVs or hybrid solutions. 

Electric power trains are locally emission free, however the energy storage, with today s battery technology, is limited in energy density to about ISOWhkg if advanced lithium batteries are used and refueling time takes a few hours. So the range and availability of the vehicle is lower than for cars with ICE power trains. 

Fuel cell technology provides the potential for a true local zero emission power train if hydrogen is used as the fuel in combination with higher energy densities and fast refueling. The energy density is mainly limited by the energy density of... 

The solution of this example is too extensive to provide herein. It is best undertaken in Exercise 19.8. In one solution, obtained by students at the Georgia Institute of Technology, using gasoline as the fuel, the entire vehicle weighs 1,750 kg and carries 74 L of fuel. Its fuel cell operates at 3 bar, provides =111 kW, has an efficiency of 43%, current density = 473 mA/cm and area = 450,000 cm. Its overall system efficiency is 8.10 km/L, overall fuel efficiency is 35.4%, and the total cost of the power train is 24,700, far in excess of the cost of a conventional gasoline engine. Note that the cost of the fuel cell is 13,300, with a mass of 25.1 kg. ... 

Efficient Mechanical Power Train The 797 power train includes a new torque converter with lockup clutch that delivers high mechanical efficiency. The new automatic-shift transmission features seven speeds forward and one speed reverse. Electronic clutch pressure control (ECPC) technology smoothes shifts, reduces wear, and increases reliability. Large clutch discs give the transmission high torque capacity and extend transmission life. The transmission and torque converter enable the truck to maintain good speed up grades and to reach a top speed of 40 mph (64 km/h). 

An emerging application for large quantities of Li-ion cells is the electrification of power trains, where Li-ion cells seem to be a proper technology which covers a broad spectrum of e-mobility applications like hybrid electric vehicles, plug-in hybrid electric vehicles and electric vehicles. For these applications a precise state determination of the Li-ion battery and its cells is mandatory to ensure a reliable operation of the vehicle. 

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