Why do we use PWM in SMPS?

The on and off of the switch is controlled by PWM that generated by PIC microcontroller 16F877A. The on and off of the switch is important because the duty cycles of the PWM is used to regulate the DC output voltage. So the desire output voltage can be produced by generate various duty cycle.

Why are transformers used in SMPS?

An SMPS transformer is used in a switching power supply to provide galvanic isolation. The SMPS transformer in an isolated power supply provides a clear barrier that prevents dangerous high voltages from passing to the output, providing safety from electrical shock at the output.

Why transformer can be used for dc?

It is because transformer workes on the principle of electromagnetic induction i.e. it will work only with currents that produce varying magnetic field that will cut the conductors and induce emf (as alternating current does ) , but dc produces a constant magnetic field which can not cause induction statically .

Why transformer is used in power supply?

In electric power transmission, transformers allow transmission of electric power at high voltages, which reduces the loss due to heating of the wires. This allows generating plants to be located economically at a distance from electrical consumers.

Why is PWM preferred?

PWM represents the most commonly employed voltage control method. An advantage of PWM control is that because the frequency is fixed, any switching noise that arises can be predicted, thus facilitating the filtering process.

What is a SMPS transformer?

Switch mode transformers (also known as switch mode power supply transformers and SMPS transformers) are using in a regulated power supply and function to step up or step down voltage or current, and/or provide isolation between the input and output side of a switch mode power supply.

Which is better SMPS or transformer?

Therefore, SMPS is a much smaller and lighter transformer that adjusts the voltage as required, which results in higher power conversion ratio. On the other hand, a coil/linear power supply applies the AC line voltage to a power transformer to lower or increase the voltage before being applied to the regulator circuit.

Why transformers are only used in AC circuits?

transformer work only on ac supply because A transformer needs an alternating current that will create a changing magnetic field. A changing magnetic field also induces a changing voltage in a coil. This is the basis of how a transformer works: The primary coil is connected to an AC supply.