A Current Reinjection Scheme That Adds Self-Commutation and Pulse Multiplication to the Thyristor Converter

An old concept proposed to double the pulse number of a line commutated converter and designated "dc-ripple reinjection," is made more effective by the use of self-commutating reinjection switches, such as GTO or IGCT. It is shown that the self-commutating reinjection switches can be controlled to force the thyristor valve currents to commutate independently from their respective line voltages. EMTDC-PSCAD simulation is used to verify that this effect adds reactive power controllability, as well as pulse multiplication, to the conventional thyristor converter