Introduction:

SMPS stands for Switched-Mode Power Supply. It is an electronic power supply that uses a switching regulator to convert electrical power efficiently. It is also known as Switching Mode Power Supply. It is power supply unit (PSU) generally used in computers to convert the voltage into the computer acceptable range.

SMPS Principles :

Conversion of alternating supply into direct supply with the help of Rectifier unit.
Filtering and smoothing of direct supply which is suitable for Electronic equipment.

Function of SMPS:

Provide DC supply to BTS(Base Trans receiver Station) and Transmission equipment.
Charging the battery boot mode
Avoid Battery deep discharge through BLVDs
DC distribution through various MCBs

Why we use SMPS ?

Switched mode power supplies are more efficient than linear power supplies. Linear power supplies regulate voltage by using a simple transformer or by changing the resistance of a component (transistor, resistor etc.) dynamically which creates a voltage drop required to get the certain output voltage. This voltage drop causes wasted heat energy. A linear PSU that converts 40v to 5v will be much less efficient than one which converts 12v to 5v because of the higher voltage drop, with the same current draw of course. A transistor can be on, off or somewhere in between. In between it generates the most heat. A switched mode power supply’s transistor in only on or off. So the resistance does not generate nearly as much heat. A buck type SMPS uses a PWM signal which turns a transistor on or off at a variable duty cycle. 50% duty cycle, where the signal is high and low for an equal amount of time, will theoretically output an average voltage of half the input voltage, but this is often never the case and it depends on other factors such as load etc. it has a capacitor and inductor at the output to smooth out the current and voltage. Most wall adapters nowadays are SMPS’s.