Telega Phase Current

Support Electric drives
1

Telega publishes information about AC current in two places:

  • phase_current_amplitude in the compact topic
  • current[2] in the dq topic

How do I calculate the RMS current per phase from these measurements? Is it

  • phase current amplitude divided by \sqrt{2} because the published amplitude is per-phase,
  • something with \sqrt{3} because the published amplitude is for the 3-phase AC system,
  • a combination of the above or something else?

Thanks,
Lasse :slight_smile:

2

The per-phase RMS current is \frac{i_{\text{peak}}}{\sqrt{2}}

so the RMS is phase_current_amplitude/sqrt(2)

or equivalently \frac{\sqrt{\texttt{dq.current[0]}^2+\texttt{dq.current[1]}^2}}{\sqrt{2}}

These may be distorted if your motor’s flux is strongly non-sinusoidal.

The Clarke/Park implementation is the amplitude-preserving form so |i_dq| matches the sinusoidal phase peak.

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