Method for controlling rectifier circuit in rolling mill, involves interrupting ignition pulse sequence for beginning of commutation periods in mains phases for duration of pulse rest period during regenerative operation of circuit

摘要

The method involves controlling thyristors (18a-18c, 19a-19c) of a non-regenerative electric rectifier (7) by ignition pulse sequences (S1, S2) during a commutation periods within a phase voltage half wave of mains phases (L1-L3). The thyristors are connected to the mains phases. The ignition pulse sequence and/or one of the ignition pulse sequences is interrupted or delayed for beginning of the commutation periods in the mains phases for duration of a pulse rest period during a regenerative operation of a rectifier circuit (1). An independent claim is also included for a rectifier circuit for switching between a multi-phase alternating current mains and a direct current circuit with a thyristor control unit.