I have been hearing about permanent magnet alternators. What exactly is that? Where are they used? Can I get one for my vehicle?
Permanent Magnet Alternators are commonly use for power generation. Automotive alternators converted to permanent magnet type are used on home grown wind Generators, Hydro Power and Homemade stand-by power Generators. Common Automotive Alternators use an electromagnet powered rotor to turn the alternator on and off. Permanent Magnet Alternators have permanent magnets in place of the electromagnet wire wound rotor core.
The reason automotive uses and electromagnet rotor core is so they can use it to control the output of the alternator. The use of the voltage regulator controls the voltage sent to the electromagnet rotor core. With permanent magnet alternators you cannot control the alternator output as it doesn't have a voltage regulator or the electromagnet wire wound core to control it.
Control of permanent magnet alternators is commonly done by varying the speed of the alternator. With permanent magnet alternators the faster you spin the alternator the more electricity the alternator produces.