| 摘要 |
<p>1,109,703. Power factor improvement. MOSKOVSKY ENERGETICHESKY INSTITUT. 17 Jan., 1966, No. 2031/66. Heading H2H. [Also in Division G3] In a capacitor bank used for power factor improvement and controlled by reverse parallel connected thyristors, current surges due to delayed angular firing of the thyristors are avoided by injecting into the capacitor a current pulse to produce a voltage greater than the supply voltage at that instant to extinguish the thyristor over the middle part of the cycle. Thyristor 1 is conductive from the beginning of a cycle until a voltage U2 is reached when the thyristor is extinguished by a pulse from a circuit 3. The capacitor voltage remains at this value until the thyristor 4 reconducts when the supply voltage U1 is again equal to U2 in the later part of the cycle. As the thyristors conduct when the supply voltage is approximately equal to the capacitor voltage large current surges are avoided. An automatic control circuit is described in the Specification, for producing timed pulses for two capacitor banks connected to a supply through star/star and star/zig-zag connected transformers respectively. Correction of individual phases is provided for.</p> |
