TV-part II

second video on transverter, specifically covering 3PH transformers, and explaining the magnetics involved.

Category:

Science & Technology

Tags:

• TV
• partII

[dancombine]

@robbiehobbie47: This is a good point you raise. The primary flux F1 is in phase with the primary current I1. This flux induces en emf in the secondary (E2), where E2 lags F1 by 90°. Due to the LC resonance, the load appears resistive, so I2 is in phase with E2. I2 creates secondary flux F2 in phase with I2. So F2 lags F1 by 90° and F2>>F1. Let me know if this is correct. In anycase, the measurements I have is that the input power drops at secondary resonance.

[dancombine]

@minde4000: The formula you describe is only applicable to sinewaves, which is not applicable to the non-linear resonant waves of the TV. You can have a calculation error of more than 30%. In my first video I calculated the VAR more accurately, by making 72 samples per cycle and using the time-avereged integral of i(t)*v(t-90°). But in my 2nd video, I didn't make those complex calculations, and estimated the VAR. I intentionally UNDERestimated. If the reality is higher, the better.

[dancombine]

@minde4000: The formula you describe is only applicable to sinewaves, which is not applicable to the non-linear resonant waves of the TV. You can have a calculation error of more than 30%. In my first video I calculated the VAR more accurately, by making 72 samples per cycle and using the time-avereged integral of i(t)*v(t-90°). But in my 2nd video, I didn't make those complex calculations, and estimated the VAR. I intentionally UNDERestimated. If the reality is higher, the better.

[selfonlypath]

@robbiehobbie47: yeah the whole story is much more complex because we're dealing with polyphase nonlinear periodic signals injected into a nonlinear permeability core. Even the 180° out phase might not be correct, check my last video where i'm transverting the 3rd harmonic & pulsing at 1st harmonic.

It would be very useful if your software could simulate anomalous reactive power amplification but again, see my last video which drives crazy any EM expert.

Merry Xmas

[robbiehobbie47]

@dancombine : In case of a pure resistant secondary load, the counter flux will be 180 out of phase with F1.

But, there will be large phase shifts within the cycle. So, the whole story is much more complex.

I will start simulating this in Ansys Maxwell 3D so I can have more accurate response to your theory.

In case you're interested, drop me a PM via youtube and we can work out offline some more detailed theory.

[robbiehobbie47]

Dan, are you sure the direction of the flux in the phase C part of the transformer (indicated by the red arrows) has the right direction? In my view this is counter flux, so the direction should be oposite, which changes the whole principle.

[minde4000]

@dancombine

250VA ferroresonant transformert: 100W input (48VDC@2amps) and 1366 VA (RMS) curculating in secondary. Ratio 1:13. BUT when I do math on your proposed blank cap firing extraction process I still get underunity. This traffo requires 24uF cap for secondary. If I split this cap into 3 caps - cap 1 is 10uF, cap 2 and 3 7uF each. If a caps 2 and 3 in my case could get charged to 400VDC @ 7uF = 560mJ. Now 560mJ x 120 discharges/second = 67W (joules)/second. 100W input > 67W output.

[JMin2020]

Thank you Dan. I appreciate your work on the transverter and you willingness to share your accomplishments.

[minde4000]

Dan,

One more thing. On you first video when caliculating circulating VARS in secondary you take I rms x V rms x sin φ = VAR. However in this latest video you did the same thing BUT then you divided VAR/2 as your final secondary VAR value. Why is that the case?