WELDING MACHINE CIRCUIT EMPLOYING SCR PHASE CONTROL USING A VARIABLE REACTOR TO PREVENT SUDDEN RISING OF SHORT-CIRCUIT CURRENT IN THE EVENT OF LOAD SHORT-CIRCUIT

摘要

PURPOSE: A welding machine circuit employing SCR phase control using a variable reactor is provided to improve the response property and reduce the generation of spatter.;CONSTITUTION: A welding machine circuit employing SCR phase control comprises interphase reactors(L1,320), a plurality of SCR rectifiers(310), and a variable reactor(330). The interphase reactors include L-shaped iron cores wound with coils which are symmetrically connected to form a loop type iron core, wherein one side of each core is connected to the neutral point of a three-phase double circuit while the other forms a first output terminal. One-side ends of the SCR rectifiers are connected the respective phase circuits of the three-phase double circuit while the other-side ends are connected each other to form a second output terminal. The variable reactor is connected to the first or the second output terminal in order to prevent the excessive rise of electric current in case of load short-circuit.;COPYRIGHT KIPO 2010