Mark Hanson via EV wrote:
Hi Ron Solberg etc All small wind turbines like my Bergey XL-1 have boost converters on them to change the varying voltage to a constant float voltage for the L16 batteries you mentioned. 13.8v is maintained per 12v increment or for your 48v system you would use a 55.2v boost regulator for float and 60V to equalize monthly (with equalize button). I used a Micrel (Google data sheet) MiC2171bu on a 24v wind turbine I had that took 6-24v in and converted up to 30v out with a bypass low drop Schottky diode when overspeeding. Look at SMA Windy Boy controller or Berger.com. Have a renewable energy day,
The modern wind generators I've seen used a PM motor. Some are DC (with a commutator), but most are AC. These will generate a voltage that varies with wind speed, so a controller of some kind is always needed.
The old ones all used brushed DC wound-field generators. They worked just like the old car generators; there was an armature and commutator, and a wound field coil. The output was regulated by the field current.
As speed increases, the field current was lowered to regulate the output voltage (and current). They worked just like the "regulator" in pre-1960's cars; a little box with two or three relays that would select off/medium/high field current. The relays were carefully adjusted to pull in at the desired voltage, and "chattered" on/off as a crude switchmode regulator. The inductance of the field winding served as the flywheel to even out the variations. This is exactly the setup we use today in a series motor controller, but with transistors doing the switching.
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