| 摘要 |
A load-commutated inverter for operating a synchronous motor having two sets of 3-phase windings. The difference of phase angles between the two sets of the 3-phase windings is 30 degrees. The load-commutated inverter is provided with two sets of inverters and a control circuit. Each of the inverters, is formed of thyristors. The inverters are coupled respectively to the 3-phase windings of the motor. The commutation of each of the thyristors is controlled in accordance with a given advanced control angle. The control circuit is coupled to the inverters and is responsive to a commutation overlapping angle of currents (e.g., IU1, IV1 in FIG. 4A) supplied from the inverters to the 3-phase windings of the motor. The control circuit adjusts the given advanced control angle so as to retain a relation: u+ gamma *</=30 degrees wherein u denotes the commutation overlapping angle and gamma * corresponds to the reverse-biasing time applied to each of the thyristors. |
