Method for controlling the converter valves of a load-guided parallel resonant circuit inverter of an induction furnace

摘要

A method for driving the converter valves of a load-commutated parallel-tuned-circuit invertor, which is supplied from a DC source, of an induction furnace is proposed, which method enables continuously variable adjustment or regulation of the power emitted to the induction furnace, a current flow from the DC source via the parallel tuned circuit being set by triggering in each case two diagonally opposite converter valves of the invertor. In each case two diagonally opposite converter valves (A11,A12 or B11,B12) are triggered in a time-delayed manner, so that a "short-circuit current" is temporarily produced from the positive terminal (1) of the DC source to the negative terminal (2) of the DC source, via two converter valves (A11,B12 or B11,A12) which are connected directly in series. IMAGE