Generator versus Alternator

[Donald B.]

Just a general question - what are the "practical" (in layman's terms) differences between a generator versus an alternator? Does one charge faster than another? Why did the car manufacturers change from the generator to the alternator.

Thanks

[John O.]

Re: Generator versus Alternator

Hi Don

If i'm not mistaken. The alternator charges at a lower R.P.M. and it takes more R.P.M. for the generator to charge. I would guess thats why the auto makers switched.

Bye..John

[Jack H.]

Re: Generator versus Alternator

The alternator outputs raw AC making it intrinsically simple (fewer moving parts & wear items inside) compared to a generator that delivers DC voltage. With an alternator (basically an AC electric motor driven backwards), its natural AC output is converted to DC using a diode bridge.

Chrysler was the first to offer alternators (1960) and Ford/GM followed (circa 1963) once they saw Chrysler's patent laid claim to a prefered embodiment (4-diode, full wave rectifier bridge). Instead of paying patent royalties to the 'competition' the other two of the big three 'complicated' their designs to incorporate a 6-diode, three phase, topology making it non-infringing.

Sadly, this put a HUGE burden on the fledgling semiconductor industry to tool production facilities to supply the US auto market demand for silicon diodes. But, once the bullet was biten the volume HELPED the semi's rapidly reduce costs and the rest is history.

Learning curve pricing is well-known and practiced in the semiconductor business. If the autos had been able to hold the design of the car constant and continually produce the SAME thing instead of changing it over and over AND they could embrace a typical semiconductor learning curve, we should all be driving cars with a typical top speed of 4000 mph that cost $6 to purchase!!!