How you doing? I'm designing a three phase voltage imbalance detector
My problem is that it must work with a delta wired power line, so, no neutral available to take measurements
I have resolved that problem for a Wye configuration with neutral, but this config is giving me some
I figured out this solution, that I consider somewhat "bloated", And I can't figure if it's the correct solution for the analog frontend of such a device.
In this circuit an optocoupler is used for re-referencing the three leg voltages instead a transformer. R11, D1, C1 and D4 are there to act as V5 does (voltage source)
then C12, R12 and R1 act as a modulator and bias source for U1. The output voltage is picked from R2 and re-referenced for a phase sum (not in this schematic)
Ignore the U2 and U3 circuits, I left it there for testing purposes.
Do you know of any other solution for voltage detection without having to resort to voltage transformers or a delta-wye transformer?
What is your advice?