Control circuit for transistor pushpull static inverter - has clock to stabilise switching frequency and load current feedback transformer

摘要

The control circuit, for a transistor pushpull static inverter, reduces losses by improving commutation and maintains frequency constant. A clock is used to stabilise the transistors' switching frequency. A control transformer (U) is used to feed back the load current to the control circuit and has an extra primary winding (III) coupled via a resistor (R3) in series with the power output transformer's (Tr) primary. This extra primary is coupled to the output of the clock (S) and is periodically short-circuited. The control transformer is coupled via a further winding (IV) to a saturating choke (Dr2).