WindBlue Power has a good FAQ section on PMA hook up and DC regulation
WindBlue Power - The best wind generator parts and PMA Permanent Magnet Alternators on the web
What I have learned so far:
Why you cannot use a Solar or PV Charge Controller for Wind
For the sake of ease we are going to talk about a 12 volt system for this next section.
As I am sure you have noticed Solar
and PV Charge Controllers come in 12, 24, 36, and 48-volt ranges, and you must match the range with your battery bank.
Here's why. Most Solar and PV controllers have circuits that will only work within a certain range of voltage and current/amperage.
For example: Lets say you have a 12v solar panel. It will put out between 0-18 volts DC and up to 3.5 amps (or 50 watts).
Most 12 volt Solar charge controllers are designed to handle up to 20 volts and 50 watts, or 3.5 amps of input power.
Most Solar controllers cannot comprehend voltages outside their range of input power, meaning if they get more than 20 volts of input they go nuts, crazy, wacko, screwball, etc.
A wind Generator
can (easily) have a range from 0 to more than 100 volts, and amperage of 0 to 50 amps (on average 2 to 30).
Now if your Solar controller is designed to handle 0-18 volts what do you think it would say (if it could talk) when it gets hit with 25 to 100 volts of DC power from your Wind Generator
with amperages up to 50 amps?
Here's my guess at what it would be saying.
1. What in the heck is this?
2. What am I supposed to do with this?
3. And last but not least,,, OUCH!
One other factor to look at on Solar charge controllers is most of them shunt when the battery is charged and that may not be the right solution for your generator. Others open the circuit and let your generator run wild.
You still have to get a wind generator charge controller for the correct battery voltage. And a wind generator charge controller will be designed to handle the wide range of input voltage and amperage from your generator.
An exception to the above are charge controllers such as the Morningstar TriStar 45,
Connecting the Alternator to your Batteries
The alternator can be connected to your batteries in several ways. The most common is to just connect it at the same point you connect your load. But if you are running a higher voltage battery bank such as four 12-Volt batteries connected in series to make 48 Volts you should consider hooking the alternator to just one of the 12 Volt batteries. The reason for this is that the alternator will not start charging
your battery until it is spun fast enough to produce more voltage than the voltage of the battery. So for example in a wind setup using our DC-540 model, it reaches 12-Volts at 150 RPM
, but it takes about 600 RPM
for it to reach 48-Volts. So you can see it would take a fairly windy day to get it turning fast enough to charge a 48-Volt battery bank but only a small breeze to get it to start charging
a 12-Volt battery.
We get a bunch of questions asking how do I regulate the voltage coming out of the alternator. The simple answer is you don’t. The battery acts as a regulator
and absorbs the excess voltage that the alternator puts out. The same thing happens in your cars charging system. If you were to disconnect the battery terminal on your car while it was running, the alternator voltage output would shoot up dramatically, frying most of the sensitive computer equipment
on new cars. So as long as the generator is connected to a battery you don’t have to worry about the voltage.
which are designed to be used with either wind or solar systems.