Apparatus and method for effecting unidirectional flow of power in a. c. circuits

Claim 1

A METHOD OF PREVENTING REVERSE FLOW OF SUBSTANTIAL POWER IN A SYMMETRICAL A.C. SYSTEM, WHICH COMPRISES: PROVIDING SWITCH MEANS BETWEEN FIRST AND SECOND PREDETERMINED POINTS IN A SYMMETRICAL A.C. SYSTEM, DETERMINING THE PHASE RELATIONSHIP BETWEEN THE VOLTAGE AND CURRENT WAVES IN SAID SYSTEM WHICH IS REQUIRED TO EFFECT TRANSFER OF POWER FROM SAID FIRST POINT TO SAID SECOND POINT, CONTINUOUSLY SENSING AT LEAST ONE OF SAID VOLTAGE AND CURRENT WAVES, ADVANCING THE PHASE OF THE WAVE WHICH IS GENERATED AS THE RESULT OF SUCH SENSING STEP, EMPLOYING THE PHASEADVANCED WAVE TO MAINTAIN SAID SWITCH MEANS CLOSED WHEN SAID PHASE RELATIONSHIP IS SUCH AS TO EFFECT TRANSFER OF POWER FROM SAID FIRST POINT TO SAID SECOND POINT, AND EMPLOYING THE PHASE-ADVANCED WAVE TO MAINTAIN SAID SWITCH MEANS OPEN DURING AT LEAST THE MAJOR PORTION OF THE TIME WHEN SAID PHASE RELATIONSHIP IS SUCH AS TO EFFECT TRANSFER OF POWER FROM SAID SECOND POINT TO SAID FIRST POINT.