forums energies: society, ecology and clean technologies

Hello, I am creating a new post to address a new parenthesis in voltage production via a universal motor. In search of a generator for the wind turbine that I am building, and after several essias with rewound alternator, dc motor etc .. I opt for the universal drill motor 220v / 500 watts as a generator. By driving the motor by hand, with the built-in multiplier of the drill (for now). I just managed to generate a voltage, I have between 30 and 70 volts continuous (without needing excitation) depending on my speed, but there is a phenomenon that I cannot explain to myself. By plugging in the output of the coals, a 12v lamp and generating at low speed of rotation, 12 volts, the lamp does not light up, although I have the adequate voltage. What is curious is that I have a solar charger which gives me 22 volts, and if I also plug in a bulb at the output of the charger, this one does not light up either, but it does charge a battery! how do you explain this, is this normal? insufficient power?

The bulb is dead

Yes but no , if I plug it into the battery it works fine. Does anyone have any idea what is going on?

are you sure the voltage rises to 12V when the bulb is plugged in?

Yes perfectly on, I connect a voltmeter in parallel. Sometimes I even have more than 20 volts, the bulb does not even hurt, it does not even react. However, the intensity generated cannot be weak at this point. I plugged in a DC motor instead of the bulb, it doesn't even move either. The bulb is 5 watts, it even lights up on a 12v 500ma transformer

A bulb is like a resistance, if you increase the voltage at its terminals, the current necessarily rises too, if it is a 12V bulb you cannot have 12V at its terminals and no (or little current) of running. With 12V, it must pump 0.4A if it is a 5W.

Is it an all-or-nothing drill or is there a variator in it?

That the DC motor does not turn is normal, the drill must take you out of the alternative ...

No, I am going out of continuous. The drill is indeed an all or nothing.

darwenn wrote:Yes perfectly on, I connect a voltmeter in parallel. Sometimes I even have more than 20 volts, the bulb does not even hurt, it does not even react. However, the intensity generated cannot be weak at this point. I plugged in a DC motor instead of the bulb, it doesn't even move either. The bulb is 5 watts, it even lights up on a 12v 500ma transformer

Hello Darwenn!

If your voltmeter is electronic, it distorts the reading because it takes the voltage peak and you generate voltage pulses that do not last long enough to turn on the light, an old needle voltmeter would give you the true value.

yes that must be it, the tension is false. Too bad.

The best general for this kind of app is a permanent magnet motor, associated with a DC-DC converter with search for the maximum power point.
The converter then automatically adapts the current it draws on the generator to always have the maximum power. Suddenly on a wind turbine the assembly self-adapts to the wind speed to always extract the maximum power.

Same principle for solar panels.