Control and diagnostics of multiple electrical generating machines using an external voltage regulator

摘要

An electrical system for an automotive vehicle has a plurality of electrical generating machines having field windings energized by pulse width modulated drive signals generated by an external electronic voltage regulator. The pulse width modulated drive signals have a duty cycle determined by the electronic voltage regulator. A controller selects one of electrical generating machines to evaluate for failure and evaluates that electrical generating machine for failure by causing the PWM drive signal for the field windings of that electrical generating machine to be disabled. The controller then determines that this electrical generating machine has failed if the duty cycle for the PWM drive signals has then not been increased by the electronic voltage regulator by a pre-determined amount. The electrical generating machines are either generators or alternators. In an aspect, the PWM drive signals for the plurality of electrical generating machines are out of phase with each other.

主权项

1. An electrical system for an automotive vehicle, comprising:
a plurality of electrical generating machines with each electrical generating machine including field windings energized by pulse width modulated drive signals generated by an external electronic voltage regulator, the pulse width modulated drive signals having a duty cycle determined by the electronic voltage regulator, the electronic voltage regulator varying the duty cycle of the pulse width modulated drive signals to control output voltages of the electrical generating machines; a controller, the controller selecting one of electrical generating machines to evaluate for failure and evaluating that electrical generating machine for failure by causing the PWM drive signal for the field windings of that electrical generating machine to be disabled and then determining that this electrical generating machine has failed if the duty cycle for the PWM drive signals has then not been increased by the electronic voltage regulator by a pre-determined amount after the PWM drive signal for the field windings of that electrical generating machine has been disabled.