electric generator and back emf

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Hi Everyone,
I am trying to connect an AC generator (small wind mill) to a load and I run into a problem there. When I connect about 1Mohm load, the generator works fine but current output is low. When I connect 1Kohm, the generator stops (because torque is higher) but current was higher momentarily. I deduced that at lower resistance I created a high back emf to the generator which caused it to stop. Is there a way to reduce back emf at 1Kohm load? A similar thing happened with capacitor instead of resistor. Higher capacitance stops generator, and lower capacitance do not.
 

back-emf is related to the rotation speed of the generator, this is not likely to stop the generator unless the speed of rotation was too high and the motor conroller has some sort of overspeed shut-down protection. sounds like the load is too high and generator can not produce enough torque to rotate.
 

With a wind turbine, the maximum power output is when the turbine is rotating at 2/3 of the wind speed. So measure the voltage off load and adjust your load to get the output voltage to 2/3 of the previous value.
Frank
 

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