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BLDC generator output current

  1. Feb 24, 2016 #1
    I'm using the following BLDC motor as part of a project to generate power:


    I'm able to spin this motor to about 3000 RPMS which gives me about 5 Volts. This is to be expected given that the motor is rated at 550 KVs. I'm using a three-phase rectifier with a smoothing cap to convert this to DC power. What I don't understand is the current produced. I'm getting about 33mA which is to low for my application. Essentially I would like to spin a small PC fan with this power. I'm able to do it but at a very low speed given that there isn't enough current flowing from the generator. What I would like to understand is why there is so little current flowing at those RPMS. I would at least expect it to be 100mA or 200mA, but this is just speculation on my part. Apologies for my noobness. Any help is appreciated. Thanks.
  2. jcsd
  3. Feb 24, 2016 #2


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    Science Advisor

    PC fans are generally 12V devices. And don't forget the 0.7Volt drop across each of the diodes. Also if you are using a half wave rectifier, the generator should be Wye connected. The motor you are using is Delta connected, so a full wave bridge is indicated.
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