APPAREILLAGE DE COMMANDE ELECTRIQUE

摘要

Electrical control apparatus including a transformer having a winding connectable in a power circuit which includes a source of alternating potential and a load circuit. The transformer winding includes at least two tap connections which are selectively connected into the power circuit with solid-state switching devices. The solid-state switching devices are gated at a firing angle responsive to an error signal. Tap-to-tap short circuits are obviated, regardless of the type of connected load, by firing control which senses the direction of instantaneous power flow, and the direction of instantaneous current flow in the power circuit.