Abstract:
A fault indicating circuit for an automobile alternator battery charging system is disclosed. The charging system comprises an alternator providing a rectified battery charging signal in response to alternator field coil excitation which is controlled by a voltage regulator that senses battery voltage. The fault indicating circuit comprises a low voltage detector circuit which provides constant DC excitation for an indicator lamp in response to low alternator output voltage and a high voltage detector circuit which provides intermittent excitation for the lamp in response to an excessively high alternator output voltage, the lamp being maintained in a de-energized state in response to the normal alternator output voltage.
Abstract:
A fault indicating circuit (17) for an automobile alternator battery charging system. The charging system comprises an alternator (11) providing a rectified battery charging signal in response to alternator field coil excitation which is controlled by a voltage regulator (15) that senses battery voltage. The fault indicating circuit comprises a low voltage detector circuit (58) which provides constant DC excitation for an indicator lamp (19) in response to low alternator output voltage and a high voltage detector circuit (57) which provides intermittent excitation for the lamp in response to an excessively high alternator output voltage, the lamp (19) being maintained in a de-energized state in response to the normal alternator output voltage.
Abstract:
Detector monitoring the function of the stator and rectifying diodes in a multiphase alternator battery charging system (20). A circuit combines individual phase signals form the alternator (22) to form an artificial neutral at which a normally symmetric wave signal is present. A first comparison means detects deviations in the normally symmetric wave signal greater in value than a first threshold voltage level. A second comparison means detects deviations in the normally symmetric wave signal lesser than a second threshold voltage level. Means coupled to the first and second comparators produce an output signal whenever the normally symmetric wave signal deviates above the first threshold voltage level or below the second threshold voltage level. The detection of asymmetry in the normally symmetric wave signal indicates a fault in the stator or rectifying diodes of the alternator.
Abstract:
Detector (28) monitoring the voltage ripple in the rectified electrical output signal of an alternator (22) in a multiphase alternator battery charging system. A circuit monitors the undulating alternator output signal and produces a signal level in response. To correct the detector operation for various magnetic phenomena present in the alternator, a first circuit measures the rotational speed of the rotor and produces a proportional signal. A second circuit determines the excitation current supplied to the field coil. The measurement and determination are separately weighted and combined to form a corrected comparison threshold value. A variable threshold circuit combines the signal proportional to the rotational speed of the rotor and the determined field coil excitation current to produce a combined signal level. Comparison means compare the signal level from the monitored alternator output signal with the combined signal level and produce an output signal level indicative of the detection of a voltage ripple in excess of the combined signal level. The output signal is corrected for the effects of significant alternator performance characteristics.
Abstract:
In situ self-diagnostic automotive alternator battery charging system. Included are: a battery (74); voltage regulator (82) sensing battery voltage and generating an excitation signal; and an alternator (22) driven by a vehicle engine provide a rectified electrical signal to charge the battery in response to the excitation signal. Electronic circuit status detectors (84, 88, 90, 92, 94, 96, 98, 100), variously coupled to the battery, voltage regulator (82) and alternator (22), maintain a first logic state when a corresponding signal characteristic is within a predetermined range and a second logic state when the corresponding characteristic is outside the predetermined range. Combinatorial logic means (86, 102, 104) respond to a logic state sequence from the detectors to identify predetermined sequences of the logic states resulting in the identification of faults in the charging system. The logic means (104) also provides a warning to the operator of detection of a fault and a display of the location of the fault as occurring in one of the major components of the charging system.