Abstract: A power conversion unit for supplying electrical power to a load from a polyphase a.c. source includes a controlled rectifier bridge connected between the source and the load. Control of the rectifiers is provided through the generation of a firing wave signal for each phase of the source which wave signals are phase displaced with respect to the phase-to-phase source voltages by a prescribed amount. Reference signals proportional to the desired output of the bridge and steering signals defining prescribed relationships between the firing wave signals are combined with the wave signals to generate signals utilized to control the conduction of the bridge rectifiers.

Abstract: A circuit for the generation or development of a gating signal for a semiconductor device which is isolated from the circuit of the device itself is comprised of a pulse generating section which feeds pulses to the primary winding of a transformer to thereby induce pulses into the transformer secondary winding. An output section is connected to the secondary winding of the transformer which provides alternately, relatively positive and negative going output signals which serve as the gating signals for the semiconductor device.