Abstract: To compensate for voltage drop upon high loading of an automotive type alternator, the output of which is rectified, a main semi-conductor control switch is connected to control the output voltage of the alternator by selectively connecting, and disconnecting current flow through the field winding of the alternator. A voltage divider is used to obtain a control voltage for the main semi-conductor switch. An auxiliary sensing circuit is connected to sense waviness, or ripple content of the output voltage and, if it exceeds a pre-determined limit, controls an auxiliary semi-conductor switch which is connected to the voltage divider to modify the voltage division ratio thereof and thereby change the regulating effect of the main semi-conductor switch.

Abstract: A generator comprises an output winding connected to input terminals of a full-wave rectifier and a field winding. A resistor and diodes are also connected to the input terminals for supplying voltage to a voltage regulator. The generator, the rectifier and the voltage regulator are assembled together within a generator housing, so that a single conducting wire is sufficient for connecting the generator and a battery. The pole cores of the generator are made of low carbon steel the residual magnetism of which has been increased by a cementation process or by insertion of high carbon steel elements.

Abstract: A generator has a positive and a negative output terminals across which a battery is connected, and another output terminal for generating an output power earlier than the positive output terminal when the generator begins to generate an output power. A field energizing circuit is connected to the other output terminal and a battery voltage responsive circuit to thereby establish a field excitation when the generator begins to generate the output power at the other output terminal and when the battery voltage is below a predetermined value, whereby the field excitation can be carried out earlier and battery discharge through the field energizing circuit is prevented during the time when the engine is stopped and a key switch remains closed.