Looking at DC Generators Fundamentals you can easily relate to Hybrid Automobiles which are powered by a fuel driven engine to create DC current that charges the batteries that drive the electric motors that drive the wheels.
Diesel locomotives are, for example, an example of a hybrid drive train, as the diesel engine does not cause the wheels to spin, but instead generates electricity that turns electric motors that then cause the wheels to spin.
There are two kinds of hybrid drive trains:
* Serial hybrid: The thing which turns the wheel is an electric motor, and the gasoline engine is used purely to generate electricity.
* Parallel hybrid: Both the electric motor and gasoline engine can cause the wheels to turn.
These "new" hybrid cars are all of the parallel design pattern. Not a one, so far, is of the serial design pattern even though that would be a much simpler vehicle to design and build. A simple-and-obvious-to-construct serial hybrid vehicle would be an otherwise pure electric car, and carry a portable generator.
When the batteries run low, fire up the portable generator and make some electricity. You could recharge the battery pack from the power grid, or from the generator, your choice. This could turn a limited range electric vehicle into one that could drive long distances.
However there are several steps of converting power (e.g. mechanical to electrical, and AC to DC). Each conversion step involves some lossage, and maybe this isn't the most efficient use of fuel.
The automakers are also working with a third type of hybrid, that they call "mild hybrid". [No information available yet]
It's not electric unless you can plug it in.
That is, many people seem to think the hybrid-electric vehicles on the market now are electric. Well, honestly, are they? None of them let you plug the car in to charge the batteries, none of them drive for any significant distance on pure electric, so how can one honestly think of them as an electric vehicle?
The electricity used in the electric motor, in all of these vehicles, comes from gasoline burned in the gas or diesel engine. These are not electric vehicles, despite the presence of that electric motor.
One day there will be 100% electric vehicles but technology will have to come up with a super/cost effective deep cell battery that will absorb and retain an amazing amount of amperage.
Here is a Youtube Video on a very old DC Generator that was steam engine driven back in 1917. It's a great example on how a driven DC Generator can be used to charge the battery pack [i.e. hybrid vehicle] or supply an amperage to a load. In this video the load is obviously the light being held for the demo...
DC Generators Fundamentals