Variable AC Voltage Power Supply
Before solid state AC voltage regulation was available or cost effective, motor generator sets were used to provide a variable AC voltage. The DC voltage to the generators armature would be varied manually or electronically to control the output voltage. When used in this fashion, the MG set is equivalent to an isolated variable transformer.
Read more about this topic: Motor-generator
Famous quotes containing the words variable, power and/or supply:
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Whose rutty bank, the which his river hems,
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—Edmund Spenser (1552?–1599)
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—Henry David Thoreau (1817–1862)