Disclosed herein are two techniques, neutral point switching and field
voltage boost, that will increase the output of today's 12 volt
automotive electrical systems in vehicle idle conditions solely by the
addition of circuitry. Neutral point switching enables the flow of a
third harmonic current, which does not normally flow at low speeds, but
only at high speed. Boosting the field voltages can be obtained by
integrating a field voltage boost circuit and voltage regulator to
increase the field voltage, and consequently the field current, above the
level obtained from the battery. Furthermore, the transient response of
the alternator to a change in load is improved by temporarily increasing
the field voltage above the level needed to sustain the load. These two
techniques are compatible, and thus may be implemented together, or may
be implemented independently. No changes to a standard alternator are
required to accommodate the proposed additional circuitry.