Baum-Perrine diagram under nonsinusoidal and unbalanced conditions

After recalling the classical three-phase Baum-Perrine construction, effective under sinusoidal and balanced system, the approach is extended, by Park transform, to the general three-phase case. Its use, based on three-phase vector concept, allows deducing, in the time domain, the voltage and current drops and let alone the power flow. In this case the compensation method deducible by the graphic way assumes peculiar importance. The use of this method puts in evidence how, when harmonic and instantaneous sequence components are present, the voltages control entail the imaginary power q_p(t) flow control. This conclusion confirms again the meaning of the q_p(t), as generalization, in terms of unbalancing and distortions, of the classical reactive power Q under sinusoidal condition.