fixed to zero. A sum of the three currents (i<sub>A</sub>, i<sub>B</sub>,
i<sub>C</sub>) has to be zero by the Kirchhoff's current law. As a consequence,
only two independent quantities/scalars are needed to describe the currents
-or Voltages which are in the fact vector in the 2D space. The polar coordinates
+or Voltages which are in the fact vector in the 2D space.The polar coordinates
system can be used but a rectangular system of alpha, beta components is equivalent
-and easier for transformations computation. This transformation of the three phase
+and easier for transformations computation.
+[[!img pxmc-pmsm-block.png size="300x" align=right alt="Basic PMSM control setup diagram from PXMC library documentation"]]
+This transformation of the three phase
system to the two orthogonal components vector is named according to its
inventor Clark transformation. The waveforms in this 2D system are sine
and cosine for steady speed state. Because realization of a controller