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