Each microwave oven has a drive for rotating dishes. This is necessary so that micro waves evenly affect the prepared food from all sides. If you have an old and unnecessary microwave, then this drive can be removed from it and it will look something like this:
If this is not available, it can always be bought on Ali Express but at a ridiculous price of 1-2 bucks.
This is essentially a synchronous electric motor with a gearbox inside the housing. By the way, it is precisely because of this gearbox that the output shaft of the motor is offset from the center.
A feature of this engine is that its rotor is built on permanent magnets, and therefore the motor can not only convert electrical energy into mechanical energy, but also vice versa.
The output voltage will naturally depend on the speed of its shaft, but because of the internal gearbox it is small. The output power that can be obtained using such a generator is of the order of 3-5 watts.
We test the electric motor from the microwave as a generator
Let's check it out. Connect the motor to the tester to measure voltage.
We will rotate the shaft with an ordinary awl to create a convenient lever. There is a hole in the shaft for this.
Even with a slight rotation, the motor produces about 150 to 250 volts. And if you increase the speed a little more, then the readings reach 550 V!
Now try to load our generator. First, take a 220 V and 3 W LED lamp.
As you can see, it shines very well.
Next, take a fluorescent lamp and connect it directly without any start-up circuits.
Burning! Electronics for ignition is not needed, as there is plenty of voltage.
Next, connect the incandescent lamp to 220 V.
Alas, she did not catch fire. The generator power is clearly not enough. It is understandable.
We connect the charger from the mobile phone.
We connect the mobile phone to charging, rotate manually.
The charge is on, the cell is infected!
There is a lot of use for this generator. Tourists, hunters, fishermen will definitely appreciate the idea and most likely will take it into service. The advantage of such a current source is that it is always ready to work, not afraid of dampness, cold, which all lithium-ion power banks are so afraid of.