Alternator with lockout mode

摘要

A lockout circuit which limits the field voltage in an alternator while the vehicle starter is activated. The lockout circuit may be configured to limit the field voltage while the charging circuit voltage is below a threshold value. A timer circuit may advantageously be employed with the lockout circuit. A temperature compensating function may also be employed to change the threshold value in response to temperature changes. The disclosed circuit is particularly advantageous when employed in cold weather conditions. A method of starting the engine of a vehicle is also disclosed.

主权项

1. An alternator for a vehicle having an engine and a charging system with a battery; the alternator comprising:
a stator having at least one stator winding; a field coil rotatable relative to the stator winding and adapted to be rotated by mechanical energy from the engine; a voltage regulator configured to regulate an output voltage of the alternator by controlling a field current through the field coil, the regulator having a strobe mode and a normal duty mode wherein, in the strobe mode, the regulator introduces a pulsed current into the field coil and, in the normal duty mode, introduces an electrical current into the field coil at a controllably varied voltage to thereby control the output voltage of the alternator and wherein, during starting of the engine, the regulator is initially in the strobe mode and is released into the normal duty mode based upon properties of the electrical current generated in the stator winding; and a lockout circuit configured to maintain the field coil in the strobe mode until a voltage of the charging system exceeds a threshold value wherein the threshold value varies as a function of a temperature value.