On Wed, May 29, 2013 at 9:47 AM, Berke Durak <berke.du...@gmail.com> wrote:
> > In fact I said the 3-phase input to the box was particularly unnecessary > *because* only single-phase was used for the box. > > There are legitimate reasons to prefer 3-phase input. If the output > of the control box is a pulse width-modulated DC signal, then you need > a high-power DC source. > There might be requirements on the control waveform. > > Using three phases you can get DC with decent ripple using only a > handful of diodes. The power never goes to zero, whereas it would go > to zero 100 times a second if you were using a full-wave rectifier > with single-phase input. If the peak power required by the e-CAT is > around 1 kW, then you would need caps supplying up to 1 kW. We're > talking ~100 µF caps rated at 350V supplying 3.5A. Such large caps > are difficult to find and it makes more sense to go with multiple caps > in parallel to supply that current. These caps would dissipate a > couple watts each. Temperature very quickly shortens the lifetime of > aluminum electrolytic caps. Hence, if you use them you reduce the > reliability of your device, which could be a problem for the e-Cat. > And the above assumes the peak power is 1 kW. > > So I don't think you can say that 3-phase input is particularly > unnecessary, unless you know things about the e-Cat we don't know. > > I don't buy it. The reactor is a sealed faraday cage, so it's not going to care about ripple or dc vs ac. It's just a thermal interface. But in any case, in the dummy run, they measured the power to the ecat so that suggests it's an ordinary ac signal. Anyway, a box powered by ordinary mains can produce any signal shape they want. They wouldn't go to 3-phase just to skimp on diodes and capacitors. The 3-phase looks more like obfuscation to me.
