Help on Full wave thyristor bridge rectifier-- control by tca785

I study the datasheet of TCA785 but it confused me work with it. Because practical application of TCA785 in full bridge rectifier is not clear. plz help me:sad:

TCA785 is used in full wave thyristor controlled circuits in the aim of capturing zero crossings. you should trigger the thyristors at the zero-crossing points to get full wave. in the datasheet you can examine application circuits.

Think this way, if thyristors has 180 degree opening angle it will act like common graetz bridge.

Changing of thyristors opening angle, you will change output voltage.

When thyristors are open (when they let current flow), then always 2 thyristors - opposite one are ON (upper left and downer right and vice versa). TCA785 has 2 output impulses (positive and negative half periods), because two thyristors in par has to work, you have 4 impulse transformers, every transistor drive 2 transformers (problem is that opposite thyristors that works together has different Cathode potencial, so you have to use separate transformers).

See your visitor messages for details.

Hope this helps,

Mr.Cube


PS. R3 has to be in series with C3 (this is error on schematic).