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B DC current from an armature and converting AC to DC...

  1. Mar 7, 2016 #1
    I cannot find answers to this on the internet. Can a d/c be made using an armature? How?
    How does one convert a/c 2 d/c (or d/c to a/c)
    thirdly, why does the band a/c d/c come up as the first result on google?

    (don't answer the last question.)
     
  2. jcsd
  3. Mar 7, 2016 #2
  4. Mar 8, 2016 #3

    David Lewis

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    Gold Member

    An armature is a set of coils connected together. If AC is induced in the armature by an alternating magnetic field, that AC typically gets converted to DC via a mechanical commutator.

    To convert DC to AC, an inverter is used. An inverter may consist of a motor-generator set, or more commonly done electronically with an array of switching transistors.
     
  5. Mar 8, 2016 #4
    Well actually, you convert a/c to d/c using diodes, and an exciter circuit, for the outer field winding's, that need to be mounted in a heat sink. Think about a common car alternator. The sine wave of the electric pulses, are clipped, by the diode board, to use only the positive pulses, the negative pluses are shunted to ground, hence the heat sink, and the number of pulses per rotation, of the spinning armature, inside the outer field winding's, determines the smoothness, of the final d/c output. In reverse, a transistorized circuit board is used, also in a heat sink, to take the steady d/c current, clip it, invert half of it, at the required frequency, of say our 110- 120 cycles/ second. Thank goodness, and we should all give a minute of silence, to the first "flying wire" transistor,and the diode, least we be driving around, plagued by vacuum tube boxes the size of a bread box's in our cars.
     
  6. Mar 9, 2016 #5
    They used to have car vacuum tube radio that size, then they went to miniature vacuum tubes and the radios became a little bit smaller.

    Before the alternator automobiles had a DC generator to charge the battery and provide current for the headlights and all that jazz.
     
  7. Mar 9, 2016 #6

    I'm well aware of this, in my fairly advanced age, but we were talking about conversions of currents. Lot's of old cars use to have their electrical systems w/ the positive terminal going to ground also, but it was the advent of modern electronic components, that allowed us to use alternators, instead of the generators, and mechanical regulators, w/ their numerous problems, such as brush ware, commutator ring burn out, regulator point pitting/ burn out, regulator hold down coil burn out, and the like..
     
  8. Mar 9, 2016 #7
    That was the fun part. At least one could feel they were doing something to tune up their vehicle.
    I really miss the carburetor freezing up in winter. and the smell of starting fluid.
    Or sticking a screwdriver in the throttle, just to show your girlfriend you knew what you were doing when it wouldn't start.
    Those were the days.
    I think I am really getting off topic.
     
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