Dragon5126
New member
A typical Battery charger puts out a half wave unfiltered pulse, the voltage regulator in or on an Alternator works as a "chopper" filter,
The voltage regulator in an alternator is on and off. Nothing to do with the type of voltage it puts out. The rectifier or diodes three is what converts it from ac to dc. By filtering out the lower ac wave. The voltage reg just turns on and off depending on the supply requirements of the system.
No the regulators no longer simply turn on and off, and havent in decades. That function stopped with the demise of the mechanical regulator, The current form of regulator functions by acting as a Voltage Chopper ( a digital form of voltage regulation). Since there is a full wave rectifier in the alternator the output is more than twice that of the excitation voltage, ( the battery output on the field coil), which then is reduced by the action of the regulator. The regulator literally cuts off the peaks of the voltage by shutting the excitation voltage off at specific set points, forcing a pure dc output. In the old mechanical regulators this function was done on the output or on the stator voltage. The current technology allows the onboard computer to monitor the output voltage and adjust the field voltage which is applied at a much lower current level therefore putting less heat dissipation requirements on the regulator. This also cuts the peaks off the output of the alternator since they literally never form, Also very few alternators actually use a diode trio, most have gone to a true bridge rectifier, which again takes advantage of a doubled output level, purer output, the need for smaller coils for the same or greater output with lower heat dissipation, and greater lifespan and efficency. Of course the manufacturers took it a little too far on the downsizing of the parts, to lower the life spans so they can still sell replacement parts.
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