Short-circuit current limiter for coupled power systems

Claim 1

AN ARRANGEMENT FOR LIMITING OVERLOAD CURRENT IN A LINE BETWEEN TWO ALTERNATING CURRENT NETS WHICH NORMALLY OPERATIVE AT A GIVEN FREQUENCY, SAID ARRANGEMENT COMPRISING A SERIES-CIRCUIT OF INDUCTIVE REACTANCE MEANS AND CAPACITATIVE REACTANCE MEANS WHICH, DURING NORMAL OPERATION, HAVE APPROXIMATELY THE SAME VALUE THEREBY TO OFFER SUBSTANTIALLY NO IMPEDANCE TO A CURRENT THROUGH SAID LINE, SAID INDUCTIVE REACTANCE MEANS COMPRISING A COIL AND A SATURATABLE IRON CORE WHICH, WHEN THE CURRENT THROUGH SAID LINE GOES ABOVE A PREDETERMINED VALUE, IS SATURATED THEREBY TO BECOME A MEANS FOR RENDERING THE RESONANT FREQUENCY OF SAID SERIES-CIRCUIT SUBSTANTIALLY DIFFERENT FROM SAID GIVEN FREQUENCY AND HENCE FOR DETUNING SAID SERIES-CIRCUIT, WHEREBY THE RESULTING TOTAL IMPEDANCE IS SUBSTANTIALLY INCURRED, THEREBY EFFECTIVELY TO LIMIT THE CURRENT THROUGH SAID LINE.