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Using SCR's as a rectifier bridge (experimental)

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joestue:
I'm not sure what the point is. they have higher forward voltage drop, and unfortunately the biggest issue with using them in a wind turbine situation is the power factor or rms input amps get really excessive as the firing angle drops out.

basically because current is conserved and there is no energy storage network, the rms amps flowing into your battery are also the rms amps flowing through the alternator.

where as a buck converter with a modest input filter (you have to have one, or the switches blow up) the output amps can be far higher than the rms input amps.

you can use a big LC filter on the input of an SCR controlled rectifier, but because the wind turbines are relatively low frequency, the energy storage requirements are very high and you need a big expensive inductor.


simply using 6 mosfets as an AC bidirectional switch to short out all 3 phases together prior to the rectifier (driven from just one gate drive transformer).. can be used to make a boost converter using the inductance of the alternator. then make the alternator bigger and sized to reach full load without the help of any voltage boost just before furling..

you then rely on the boost function to get power out of the turbine in lower winds. you don't even really need to use high quality diodes for the rectifier, if the frequency is low, like say below 10 khz.. although it might be better to buy fast diodes.

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