Why transformer not produce DC current?

Why transformer can not be used in dc supply?

The transformer cannot be used in the DC supply because it keeps on alternating its current, whereas the DC supply current should be constant.

Can a constant dc current induce a steady state voltage in a transformer?

No. A constant DC current of sufficient magnitude induces smoke in a transformer.

What happen when 220v dc is applied to a 220v ac single phase transformer?

The current would rise until it blows the fuse or breaker and that would produce an arc as the transformer's inductance tries to maintain the current.

Why the windings burn when transformer is operated in DC?

Transformers are not intended to be operated in DC. DC does not provide the continuously fluctuating current that a transformer requires in order to function. On DC, a transformer will act as a transient mode inductor, and settle out to a high current state, destroying itself.

Why diodes are used after center tapped transformer in dc to ac inverter?

Diodes are used after a center-tapped transformer in a DC to AC inverter to rectify the alternating current (AC) output of the transformer into pulsating direct current (DC). This rectified voltage is then smoothed using filters to produce a more stable DC waveform. The diodes act as one-way valves, allowing current to flow in only one direction, thus converting the AC voltage into a pulsating DC voltage.

Why transformer do not operate with DC?

Transformer works with varying flux. DC won't create it. Only AC produce varying flux.

What device can be used to increase current in a DC circuit?

Transformer or instrument transformer. It can increase and decrease current output.

Can a constant dc current can induce a steady state voltage in a transformer?

No, the current has to change for a voltage to be induced in the transformer.

If DC is applied to the primary of a transformer is there any current in the secondary and if there is then whether ac or DC?

first, understand that a transformer is an AC DEVICE. it wont work on dc...

Why doesn't transformer work on a DC supply?

to have transformer action there should be an alternating magnetic flux.but dc supply cannot produce alternating flux.

What will happen to the transformer if DC voltage is applied to the primary winding?

DC current will not pass through a transformer, in the sense that a DC current on the primary will not produce a DC output from the secondary. A constant DC current will not produce any output from the secondary but there may be transient effects as the DC current is connected or disconnected (in which case, it's really an AC current, isn't it?) More about this below because I don't think that's really the question. If you pass DC current through either winding of a transformer, two things will happen. First, you will heat up the transformer and, if you have enough DC current, you will burn it out. Second, you will induce a magnetic field in the core. The more current, the closer the core gets to "saturation" or the maximum field it can support. This is important if there is both DC and AC current present because the more DC field in the core, the less core capacity is available to "transform" AC current. As the core operates closer to saturation, the AC waveform will be distorted and some of the AC power will be lost to heating the transformer. For example, if the primary of a transformer is connected to an AC source, and a DC source is connected to the secondary, then the primary current drawn by the transformer will increase, possibly enough to destroy the transformer. There are special transformers, called magnetic amplifiers, which take advantage of this effect to use a DC current to modulate an AC current. There are transient effects of DC currents in a transformer winding. As the DC current magnetizes the core, energy is stored. When the DC current is disconnected, this stored energy wants to leave the core. It can do this by inducing a voltage in either of the windings. If both windings are open circuit, this voltage can be very high. So you may see a spark jump when the DC voltage is disconnected. In a large transformer, this discharge may break down the transformer insulation and damage it. Some switching power supplies take advantage of this effect in which case the transformer is wound slightly differently and called a "coupled inductor."

Can you step up or step down the DC voltage by a transformer?

You need alternating current for a transformer, for DC you would have to interrupt the power supply to make it effectively DC pulses.