Graham Gunderson's Energy conference presentation Most impressive and mysterious

[minnie]

  Chet K,
         PM. me and explain what was wrong.
         I've learned a lot from MH.
               John.

[poynt99]

Considering TK's described scenario, a question to all:

With a given black box power source producing a pure sine wave, and when measured the voltage and current are precisely 90º out of phase, could there be real power delivered and measured at the load?

See attached representation of this hypothetical setup.

[poynt99]

If this is considered as the "input power" to the device, then I am happy to report that I have a handful of devices here in my lab that also count as massively OU, because the "input power" measured at the primary coil is also made up of current and voltage waveforms that are 90 degrees out of phase, hence resulting in a "zero" average input power. Yet the secondary outputs of the air-core transformers will light up bulbs, charge capacitors to high voltage, even run motors.

I didn't say the input power is to be measured at the primary coil.

Input power must always be measured at the source itself. In the case of Gunderson's H-bridge, that would be right at its output. Just as in the case of Ainslie's battery, where the measurement should have been taken right at the battery terminals, not at the other end of 30 feet of wire where the "phase" relationship becomes grossly skewed.

[TinselKoala]

I didn't say the input power is to be measured at the primary coil.

Input power must always be measured at the source itself. In the case of Gunderson's H-bridge, that would be right at its output. Just as in the case of Ainslie's battery, where the measurement should have been taken right at the battery terminals, not at the other end of 30 feet of wire where the "phase" relationship becomes grossly skewed.

Well, then, my measurements of my devices definitely qualify, because there is very little distance between the thick PCB traces that connect the mosfet Drains to the capacitors of the tank circuit and the primary coil, and I am attaching my probes quite near the board or even sometimes directly to the mosfet drains, whereas the coil itself has perhaps 6 cm (x2) of straight wire standing it off of the board. The 0.25 ohm non-inductive Ayrton-Perry-wound current-viewing resistor pair is at the board end of one of the coil legs.

However as you have poynted out, Gunderson's measurements are apparently taken nearer to the transformer rather than directly at the H-bridge output. The actual distance is unknown (at least by me).

[TinselKoala]

Considering TK's described scenario, a question to all:

With a given black box power source producing a pure sine wave, and when measured the voltage and current are precisely 90º out of phase, could there be real power delivered and measured at the load?

See attached representation of this hypothetical setup.

Even though the current and voltage are 90 degrees out of phase, the _current_ is very real and in the devices we are discussing can be pretty large, tens or even hundreds of amps. This current produces a very real, changing magnetic field, which in turn can induce a voltage in another magnetically coupled coil, even at some distance. Can this induced secondary voltage then provide real power to a load?