Parallel hybrid electric vehicle

Fuel cell hydrogen cars are not ready for the market but they represent another element in favor of electrification, that makes its future marketing possible as an alternative or in parallel with hybrid electric vehicles (HEVs) and battery-powered EVs. Therefore, at least three large families of products should be considered hybrid vehicles with internal combustion engines (ICEs) onboard, EVs powered by batteries recharged from outlets, and fuel cell hydrogen vehicles. 

SPC static power converter Figure 6.2. Parallel hybrid electric vehicle... 

Hybrid thermal vehicles are more expensive than traditional vehicles, because they include more than one energy source on board. However, there are some components of traditional vehicles which are not required for hybrid vehicles and can be made some savings. For instance, in the series conhguration there is no need for the gear box because the electric drive regulates the motor speed electronically, transmission is simplihed and differential is useless if the motors are directly connected to the wheels. The starter can be eliminated in both series and parallel conhguration since electric machines do not need any specihc devices to start. Many hybrid vehicles are currently on the market and this sector is growing rapidly worldwide. 

The degree of hybridization is a useful parameter characterizing parallel hybrid vehicles. The value of this parameter is defined as the total power of the electric motor divided by the sum of the total power of electric motor and IC engine, according to the following equation ... 

There is a large number of possible variations for the parallel hybrid configuration, besides that shown in Fig. 5.18, proposed by most of the major automobile companies. Some of them, for example, have a small electric machine in line with the crankshaft, where is usually located the flywheel in a IC engine vehicle. Another parallel hybrid configuration has the IC engine and the electric drive connected to different axles, as shown in Fig. 5.19, in particular in this case the IC engine drives the front wheels, the electric system the rear wheels and the road... 

As part of an interdisciplinary study we are working on emission control catalysis for an extended parallel hybrid concept [1-5]. The main elements of the experimental car developed at the Swiss Federal Institute of Technology are the combustion engine, operating in a fixed cycle mode, a flywheel as a short term energy storage device, an electrical machine and a continuous variable transmission. One of the features of this hybrid vehicle is the so called intermittent... 

In a parallel-hybrid [Figure 7.2(b)], there are dual transmission systems a mechanical one driven directly by the engine and an electrical one driven by the electric motor. A parallel-hybrid corresponds to a conventional vehicle with a smaller engine and a larger battery. To date, most automotive manufacturers... 

---