By using the present invention, {TAIL ~ the power factor} is held constant by {HEAD ~ a closed loop feedback} 
By using the present invention , { TAIL ~ the power factor } is held constant by { HEAD ~ a closed loop feedback }
OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD