how can we convert AC power to DC?

Question

what is the amplifier, and how can we use transistors to convert AC to DC.

Answer 1

conversion is usually done with diode rectifiers. see link.

Answer 2

AC power is converted to DC power using a device known as a diode. There are two kinds of diodes, the most common is a solid state device that is made of the same materials as a transistor. The other type of diode is a vacuum tube type diode. Both are basically switches that turn off and on when voltage is applied that is either positive or negative. Since an AC signal varies with the frequency between positive and negative, when the signal is applied to a diode, only one half of the signal is allowed to go through the circuit. This results in a signal that varies from near zero to the peak voltage and then back to zero. Depending upon how the diode is configured, either the positive or negative half of the AC sine wave is allowed to pass.

With additional components, the waviness, or "ripple" of the sine wave is flattened out to give a more nearly constant voltage approximating the constant voltage that you get from a battery.

Here is a link that describes solid state rectifiers.

http://en.wikipedia.org/wiki/Rectifier

For large current applications and very high voltage applications, the old style vacuum tube rectifiers are still used.

Answer 3

Transistors are generally not used to convert AC to DC.
Diodes / rectifiers are used. A diode is like a one way valve - it will allow a positive going portion of the AC through and block the negative portion. The result is a pulsating positive voltage on the other side of the diode. This is called half wave rectification - if four diodes are used in what is referred to as a bridge, full wave rectification can take place. In this way, all of the AC signal is converted to a positive DC voltage. Capacitors are then placed in parallel with the output to smooth out the humps and bumps of the rectified AC voltage.

Answer 4

I think you are in a wrong way to ask your question. Amplifier can be a transistor up to a big kit that increase the amplitude of a wave. It's bias depends on what you want. And you want a DC supply for your Amplifier you can find it in other answers. It is better U find books that has simple circuits.

Answer 5

You use diodes or recitfiers to change AC to DC. They are rated in voltage and amps so you will need to know how much power you need . If you are looking for a certain DC voltage you may also need a transformer to step up or down the AC voltage before changing it to DC. Most DC power supplys use a regulator circuit and capacitors for filtering the AC hum out.

Answer 6

On board nuclear submarines we have a device called an AC/DC motor generator.

Normally power is provided by the nuclear reactor...which creates steam...which turns a turbine generator...which produces AC power.

A small part of this AC power is fed into the AC end of a motor generator...this turns the motor which is attached to a DC end which acts as a generator.

The DC current is then sent to a large battery in the sub to charge it, and keep it charged.

If the reactor fails....then the turbine generators stop producing AC power....and then power is drawn from the battery to the DC end of the motor generator...which then turns the DC end as it is now acting as a motor....and that turns the AC end which is now acting as a generator.

I'm sure you meant on a much smaller scale....but this is one way of doing it.

Answer 7

The surest way I know of converting DC to AC is by the use of inverters/power inverters.
Now as per your question, transistors are components required to build an inverter. There can be many ways by which transistor and their combination can be used to construct an inverter. Then you need a switching circuit to drive the transistors to operate as inverters. Google it or use a standard textbook to find the inverter circuit you want and then you can do the same.

https://www.electrikals.com/

Answer 8

Actually it's a little semi conductor called a ''Diode''. This nifty little invention allows electricity to flow through it in one direction changing AC current (which flows 2 ways) into DC current(which flows in one direction).

Answer 9

A full-wave bridge rectifier. Four diodes connected together in a certain configuration.

Answer 10

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