Output circuit for portable generators

Abstract

An output circuit for a portable generator having a plurality of output windings provided separately from each other, and control winding provided separately from the output windings. A plurality of thyristor bridge circuits each having thyristors are connected respectively to the output windings. A superposing circuit superposes outputs from the thyristor bridge circuits one upon another to provide a first superposed output voltage. A rectifier circuit is connected to the control winding. The rectifier circuit is disposed such that its output voltage is superposed upon the first superposed output voltage to provide a second superposed output voltage. A control circuit is responsive to the second superposed output voltage for concurrently controlling voltages applied respectively to the gates of the thyristors of the thyristor bridge circuits to thereby maintain the first superposed output voltage at a constant value. An FET is connected to the output of the superposing circuit, and is connectible in series to an external load, for controlling supply of current flowing through the FET to the external load. A current cut-off circuit detects overcurrent in the output circuit and operable, upon detection of the overcurrent, to cause the FET to be turned off to thereby cut off the supply of current to the external load.