Frequency doubler for three=phase current - has only six thyristors and one three=phase transformer

摘要

The frequency doubler has a transformer with three limbs each with two windings. Six thyristors (11 etc.) are connected in pairs: one pair to each phase; the thyristors in a pair being connected to opposite ends of primary winding (15 etc.) associated with that phase. The other ends of the two thyristors in each pair are connected directly to a phase line (1-3). Each secondary winding has a tapping which is connected to a shared rail. The three secondary windings (15 etc.) of the transformer are connected to output terminals. Only six thyristors are needed to perform the frequency doubling, and this reduces the cost.