Anyone who is familiar with the design of an asynchronous motor knows very well that it will not simply work in generator mode. The whole point is the absence of a magnetic field capable of creating an electromotive force in the windings of its stator. But what happens if you modify the motor rotor with permanent magnets? In essence, the result should be a generator capable of converting mechanical energy into electrical current. Let's check.
Will need
- Neodymium magnets, in large quantities and in a variety of forms can be purchased at AliExpress.
- Two-component adhesive - epoxy resin.
- Masking tape.
Converting an asynchronous motor into an alternating current generator
We open the engine housing by unscrewing the mounting screws. Remove the cover of one of the sides.
We pull out the anchor, which is also a squirrel-cage rotor.
We inspect the stator for damage just in case there is any damage. And we decide on the alternation of permanent magnets.
Neodymium magnets are flat rather than round because they will be easier to install.
We take the approximate location of the magnets on the rotor.
Cover the anchor with masking tape and repeat the arrangement.
For clarity, we draw the poles of the magnets.
We drill blind holes according to the diameter and thickness of the magnets. We dilute the epoxy resin and glue the magnets flush into the recesses.
We paint all parts of the electric motor for aesthetic appearance and protection against corrosion.
Reinstall the rotor. We perform assembly in reverse order.
We fix the engine cover with bolts.
Generator check
We connect a drill or screwdriver to the motor shaft.
We provide rotation. As you can see, the output voltage is present.
Now we connect the load. This is a 220V and 5 W fluorescent lamp. Since the motor is three-phase, to concentrate energy at one point, we shunt the free winding with a capacitor.
The lamp shines brightly, almost as if it were plugged in.
Power, voltage, required torque - all this will depend on the model of a particular electric motor.
Conclusion
In this example, we have a generator that requires high speeds. Theoretically, of course, it can be used, say, in a windmill and remove a small voltage of about 20-30 V. It will work quite well, since there is practically no magnetic sticking in it and the wind will spin the blades without any extra effort.
