I got around to building a power supply which would allow me to track the AC waveform. I have several uses for this wave. First i plan to use it to control the power factor to the spot welder. The concept here is to count every half wave. I can easily reconstruct a complete wave or a number of waves. This is interfaced with the host microcontroller via two diodes wired for full wave rectifcation. (not to be confused with full wave bridge). The DC side already has a full wave bridge. The reference point being ground, and the output of my full wave rectifier gives me a pulse for every 180 degrees of power.
In theory i should be able to fetch the zero power condition, ie. 0,180,360. but the reality of my electronics thus so far is 20 degrees on either side of the wave. I need to work on the resistor divider section. I may end up using a summing amp so that i can offset the wave by 1.5v and limit the amplitude to a safe 5v.
As can be seen in the photo my code is doing what it is suppose to. However the hardware is not scaling the wave correctly. I have a small phase shift that is offsetting the zero cross detection. The high current transformer is very reactive when near saturation and it would not take kindly to an abrupt disruption in current flow. I don't want to see exactly what happens if i try to use it as is.
Before i attempt a test run i need to correct the phase shifting and offest the voltage in order to properly align the IRQ with the power wave.
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