{HEAD ~ The system} 1, wherein the back EMF is induced in {TAIL ~ a sensing coil} separate from the stator coil 
{ HEAD ~ The system } 1 , wherein the back EMF is induced in { TAIL ~ a sensing coil } separate from the stator coil
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH