There is a little known effect in electric motors know as "cogging". If you're selecting a motor for your wind generator you need to know what cogging is and how it will affect which wind generator motor you should buy.

wind generator motor "cogging" isn't an effect that only affects wind generators. In fact every single electric motor can suffer from it. It's especially important in wind generators because it can affect your wind generators performance. Let's take a look at what cogging actually is.

Cogging is the interaction between the permanent magnets in the motor and the stator slots. When they line up the motor 'sticks' and it's harder to move it from that position. How do you tell if your motor has cogging? It's quite simple actually. All you need to do is turn your motor by hand for a couple revolutions. If the motor 'sticks' in certain places your motor is suffering from cogging. On the other hand, if your motor turns freely with barely any effort your motor is well suited for a wind generator. Why does this matter anyways?

Let's say your wind generator blades start turning at 8MPH (with no motor). If we add a motor that has no cogging and spins very easily your wind generator will still start up at 8MPH; however, if we add a motor that cogs your wind generators start-up speed may rise up to 10MPH (it depends on the motor and how much cogging it has). This happens because the wind generator is trying to turn, but the motor is getting stuck when the magnets and stator coils line up.

If you live in an area where you don't experience consistent high wind this can really affect how much energy your wind generator produces. I do need to mention that if you don't have low winds or don't care about the low end of energy production it doesn't really matter if your motor cogs or not. Once it's spinning the power lost is minimal (but still some because the motor still cogs, but the turning of the blades is enough to overcome the sticking).

What's the Solution?

Well, when you're looking for a motor I highly recommend the Ametek or Windblue motors. The Ametek motors have no cogging and the low wind speed Windblue motor has no cogging either. Whatever you do don't buy vacuum cleaner motors. Although people advertise them as 'wind generator motors' they aren't. They have heavy cogging and don't produce hardly any power.

By keeping this in mind when buying a wind generator motor you can greatly increase the range in which your wind generator can produce power. If you have any more questions about cogging just leave a comment and I'll answer them for you.