Reactive power - Reactive Generator research from GotoLuc - discussion thread

[poynt99]

poynt99, This would be only valid, if we would be discussing i^2*R losses inside the Generator or the
power losses inside a battery inner resistance, which does not apply at this
circuit over here. So a BIG NO to inverting the 2nd channel on the Scope !

We really need to see the input power into the LCR tank circuit and so we need the scond channel not to be inverted !

Regards, Stefan.

Stefan, I don't think we are discussing the same topic!

Proper phase of the measurement probes is of the utmost importance in this situation, and it certainly is relevant here.

We ARE attempting to get the input power from the grid, and in order to do that we need to set up the probes as I have shown AND invert CH2 in the scope. Please go back and study my diagrams more; it is very clear as to why this must be done this way in this case.

[poynt99]

Hi poynt,

please find the attached scope shots below. First is the standard way I've been doing it and the second one is selecting Invert in channel 2 menu.

This is my circuit powered by my variac from the grid and with a 5 Ohm 1% 50w rated load Resistor on the Neutral leg of the primary (per CSR). Channel 3 is displaying the voltage across that load. I didn't connect channel 3 probe ground so not to affect CSR. So all ground points are standard Grid side Neutral after the 0.1 Ohm CSR

Let me know what you thing

Luc

Luc.

I see the problem now, and silly of me to have missed it before.

Your MATH trace measurements, i.e. MATH max and MATH min, are not the ones you need to be using. The measurement that you need to use in order to see what the net power is, i.e. net going back to the grid, or net being consumed by the circuit, is the MEAN (average) of the trace. This is a single measurement and will tell us the net average value of the MATH trace. Now, in order to get a relatively accurate measurement of the average power, you need to display about 10 cycles. So get about 10 or more cycles on the display and use "MEAN", not "Cycle MEAN" measurement on the MATH trace.

Test again using this setting, both with CH2 not inverted and inverted. They should produce opposite numbers, for eg. +10VV, and -10VV.

[gotoluc]

Okay poynt, will give that a try after dinner.

Luc

[poynt99]

At everyone,

I've attached 2 scope shots. The only change in the circuit  between both scope shots is, the first is with the Secondary shorted and the second is with the Secondary open.

Now you can see what happens in each case and why the preferred is with the secondary shorted.

Luc

Luc,

In the second shot with the secondary open, it appears that the MOT is going into core saturation. I'm not sure why it would be doing so as the primary current is not that high, is it?

I've posted this to some guys that are smarter than me (doesn't take much), so we'll see what they say.

[gotoluc]

Luc,

In the second shot with the secondary open, it appears that the MOT is going into core saturation. I'm not sure why it would be doing so as the primary current is not that high, is it?

I've posted this to some guys that are smarter than me (doesn't take much), so we'll see what they say.

I don't know? all I see is the primary current is 327mA with Secondary Shorted and more then doubles 768mA when open.

I'll let the smarter ones figure this out

Luc