In {TAIL ~ the synchronous motor}, {HEAD ~ the control means} may repeatedly control the switch so as to transfer from the synchronous operation to the start operation and transfer to the synchronous operation again when power swing occurs 
In
In { TAIL ~ the synchronous motor } , { HEAD ~ the control means } may repeatedly control the switch so as to transfer from the synchronous operation to the start operation and transfer to the synchronous operation again when power swing occurs
REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH