Voltage values considered in the context of the invention are {HEAD ~ absolute voltage values} of {TAIL ~ voltage phasors} representing a three phase system 
of
Voltage values considered in the context of the invention are { HEAD ~ absolute voltage values } of { TAIL ~ voltage phasors } representing a three phase system
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH