Reactive power - Reactive Generator research from GotoLuc - discussion thread

[poynt99]

I don´t think so.
Just short out the cap and place a positive voltage on the channel 1 from the grid.
Then a positive input current will flow through the transformer coil
which is registered right in the shunt as a positive value !

So no need to invert the scope channel !

Regards, Stefan.

Yes, you are absolutely correct, IF you wanted your power to come out as a positive result instead of negative.

So let me repeat:

Power sources, when measured properly, have a NEGATIVE POLARITY, and elements that dissipate power have a POSITIVE POLARITY.

So in the case of my diagram, and if you invert channel two as noted, you will not only get the correct polarity of the resulting grid power, but the phase relationship between the voltage and current will be displayed correctly. This is actually basic electronics, but most people forget. If you don't believe me, start at the bottom of the grid generator and going clockwise, use your finger and trace around the circuit in a loop, noting in your mind the polarity of the probes. You should be saying to yourself "...negative.....positive....positive....negative". Notice the inversion? To be correct, we should have the CH2 probe inverted so that we would say to ourselves as we travel around the circuit..."negative...positive...negative...positive". The reason we DON"T connect the scope this way, is because the scope gnds must be commoned. So instead, we connect it as shown, and to be 100% correct, we should invert channel 2 in the scope. I know no one does this, but they should when testing under the circumstances we are dealing with here where phase and power polarity means everything.

[poynt99]

Hi poynt,

sorry for staying out of the discussion. I needed to do this to stay focused on my tests in hopes to better understand the circuit with my way of understanding which is non conventional I know but this is what allowed me to come up with these ideas.

So, don't take it personally. Your knowledge is and has been very helpful.

No problem Luc.

I see you have posted the below diagram for probe position, which are my probe positions. However I see you say to invert Channel 2 (current probe) is this the correct way?... and do you wish I test it this way and post the results.

Thanks for your time

Luc

Yes thanks, I would appreciate seeing this. I am not expecting your resulting net power to remain negative. In fact I expect it will go net positive, which would indicate more power going back to the grid than what is being used by the circuit. However, the phase relationship between the current and voltage might change. If it does change and you re-adjust to get your 90 degree phase shift again, the results may be different.

[poynt99]

Here are some simple diagrams I made a while ago to explain this same power polarity issue to Rosemary Ainslie, because she had (has) the same mental block about this.

[allcanadian]

@Gotoluc

What would be needed next is a special circuit that would take high current lead acid battery DC and make ACBUT the circuit needs to handle the return (reactive circulating current) back to the batteries. An off the shelf Inverter cannot do this. So if you can develop a DC to AC circuit that can do this you would be my hero.

I believe you already have it in your circuit but it just needs a little clarity. An AC signal is dictated by two changing DC half cycles and if a circuit elements instantaneous voltage is higher it's a generator function and if it's lower it is a motor function. In an AC machine the instantaneous voltage relates to the rate of change of the expanding/contracting field, ie.. a moving magnet. A standard inverter cannot work here because energy is dissipated on the DC primary side regardless of whether the load becomes a source or not.


If you want a true AC source from a periodic alternating DC source then the AC source must be a series resonant circuit which you already have to some extent with your series capacitor off the AC generator. Now if we replace the AC generator with a large inductor then we have an AC generator (kind of) with no expanding/contracting field source other than the reactive current circulating in the system. Here we should remember that all those silly magnets in our generators moving past our coils ever did was induce a voltage "higher" than the instantaneous reactive current voltage which is why we called it a "generator".


Now if we added a large inductor in place of the generator and periodically charged your series capacitor when it is at peak voltage with a higher DC voltage of the correct polarity then the alternating current oscillations in the system would be maintained. The reactive current integrity would also be maintained and the AC system would be allowed to act like a true AC system should. The most efficient way to periodically charge the series capacitor is from a discharging inductor.. ie boost converter/joule thief. A voltage source such as a capacitor/battery cannot be used to charge the series capacitor otherwise you will lose 1/2 the Energy.. ie the parallel capacitor paradox.


Note: it would be very easy to measure the true input as the input is now DC.


Good luck


AC

[gotoluc]

Thanks for your input AC

Sounds great!... could you please take my basic circuit below and add the components so we can see what it may look like.

Thanks for sharing

Luc