Contexte: a DIY small wind turbine pancake generator, made with 2 rotor plates of 12 rectangular magnets, and one stator of 9 coil wired. After the generator, the 3 alternative electricity phases are transformed into direct current thanks to 3 bridges rectifier (one for each phase). After the rectifier, a LM317 circuit limits the voltage, in order to load battery, or an arduino board, or any else device.
Problem: at low speed of wind, when the generator charges a battery (or load arduino board, etc ...), the load generates a break onto the rotation of the wind turbine. The power of wind is not enough to maintain the rotation speed face to the reverse force generated by the load of the devices.
Question : Every things being equal, does the break phenomenon will be less important if we put magnets with low force (but with same shape) ?
Additional informations: Currently, I have build a DIY generator for a DIY vertical axis mini-wind-turbine. This generator is made with magnets and coils. The magnets currently used are very strong. The resistivity when it charges a battery is too important when wind is very low. Then, I wander if reducing the strength of magnets, choosing magnets with same surface, same shape of surface, but less strong than those currently used, without changing anything else, will reduce the resistivity ?
Said differently: For a pancake type generator, what will the effect of a reduce of the magnetism force of magnets (keeping the same magnet surface shape x*y, but decreasing the height h, the thickness) on the reverse electro magnetic force created when this pancake type generator is run by a mini wind turbine and feeds a charge (like a battery).
To better understand the system, I give you this following little sketch. You can see the general system. The type of pancake generator I'm talking about. The effect on rotation per minute when the generator loads a battery and when it does not, for a same low wind speed. And the question about the magnets.
My question is really focused on effect of the change of magnet force, regarding the RPM when appears the reverse electromagnetic force due the load of a device, everything else equal. Will the RPM be less slowed with lower force magnets ?
Whatever the effect on voltage or intensity, the question is really only focused on effect of the change of magnet force.