Introduction to Power Supply

Hello fellows, I hope you are doing great. In today’s tutorial, we will have a look at Introduction to Power Supply. The power supply is a device that provides the electrical loads connected with the supply. Normally it used to transform other types of energy such as solar, mechanical, etc into the electric power. The power supply is also known as a power supply unit (PSU), a power adapter.

There are different types of power supplies such as DC power supply, AC power supply, etc. In today’s post, we will have a detailed look at different types of power supplies their working, applications and some other related parameters. So let’s get started with the Introduction to Power Supply.

Introduction to Power Supply

• The power supply is an electric instrument that used to deliver electrical energy to the electrical load connected with it.
• The basic operation of a power supply is that it transforms electrical current received from the input source to such level of current, voltage and frequency that can operate load.

• Due to that power supplies also denoted as electrical energy converters.
• Power supplies are available in two forms first is a separate supply that delivers power to load and the other is built-in that is assembled with the device that has to use power.
• Examples of built-in power supplies are computers, laptops, mobiles, etc.
• There are some other functions that power supply do are to remains current used by the load at the safe level, cut off the use of the current in case of any fault, improvement in the P.F store the power for further use.
• In power supplies there are 2 main connections first is an input that received electric current from the source and second is the output that has more than one terminals and provides power to the load.
• The input current of power supply can be obtained from the grid station, battery, cells, generators, solar cells or other power supply.

Power Supply Classification

Functional

• There numerous methods to categorize power supplies such as functional specifications.
• For instance, a regulated power supply maintains the value of output voltage at the output terminals instead of variation in the current used by the load or input voltages.
• But the output voltages of unregulated power supply do not remain constant with the variation in the input voltage or current consumed by the load.
• The output voltages of variable power supplies can be controlled by using the knobs on the power supply or by varying the input control or by using these two at a time.
• There is a power supply whose output does not rely on the input is known as an isolated power supply.

Power Supply Packaging

• There are different packaging teachings of power supply and each has its own specifications.
• For instance for circuitry testing a bench power supply is used that is a stand-alone desktop unit.

• Open frame power supply has a limited mechanical packaging, occasionally containing of only a mounting base, these are usually built in the different machines.
• The Rack Mount power supply is manufactured to be installed in the rack of any electric device such you ever have seen in the racks of PLC.
• Such power supplies that are installed on the same PCB board with the load.

• According to power conversion methods power supply is categorized in the two types first one is linear and the second one is switching.
• The input power in linear converts is directly processed and its all power converter elements are working in their linear functioning portions.
• While in switching power converter input first is transformed into AC or DC before processing.

Types of Power Supply

• There are numerous types of power supply lets discuss them with the detailed.

DC Power Supply

• The power supply that delivers the constant value of DC voltage to its output is known as DC power supply.
• The input source of dc power supply can be either DC or AC such as the main power supply.

AC to DC Power Supply

• These power supplies deliver DC voltage to the load but their input is AC voltage. These power supplies also use a transformer for varying the level of voltage at input terminals.

• The output of the transformer is then converted into DC by using rectifiers. There are two types of rectifiers first one is a half-wave rectifier and the second one is full wave rectifier.
• The output of the rectifier circuit than a filter to make pure DC by using a filter circuit.

Switched-Mode Power Supply

• In this type of power supply, the AC input received from the mains is rectified into the dc voltage and remove fluctuation from it by using filter circuits.
• These dc voltages are converted into the high frequency with the switching circuitry that generates AC current that will flow through the transformer of high frequency.

• There is a very high frequency is used for switching normally ten kilohertz to one megahertz. So the transformer is used for these high-frequency voltages and filtering circuits.
• The output of the transformer is then converted into DC by using the rectifier circuits.

Linear Regulator

• The linear regulator is used to make fluctuating DC voltage into the constant DC. They also provide protection to the power supplies from overcurrent by limiting current.
• In different power usage applications, the constant value of voltage is needed to form the power supplies but in some supplies voltage changes with the variation in the impedance of the load.

AC Power Supply

• The input source of AC power supply is the main supply after getting supply from the mains transformer further step up or step down to provide the required voltage.
• In these power supplies also filtration process done getting output from the transformer.
• In some cases, the isolation transformer is used. In some ac power supplies, there is no isolation from mains to the power supply due to the transformer. Such a transformer is known as an autotransformer.
• Some AC power supplies deliver the constant value of voltage and current and their output changes according to variation in the impendence offered by the load.
• If the input of AC supply is dc source such as battery then there is a need of inverter to convert it into AC.
• There are 2 main types of AC power supply first one is a single phase and the second one is 3-phase.
• For a generation of AC power normally, synchronous generators are used at the generating station.
• The difference between the one phase and 3-phase is the constancy in delivering.
• AC is used at different levels of frequency and voltages in different countries such as 230 volts, 50-hertz frequency, 115 volts sixty-hertz frequency or in some case frequency is four hundred hertz.

AC Adapter

• AC adapter is also called plug pack, plug-in adapter, or wall wart is built in the ac main power plug.
• Its output is either AC or DC that transfers to the load through the wire some adapter provides more than one outputs that can be delivered through more than one wire.
• Universal types of AC adapters have switchable input connectors to get different AC mains voltages.
• The ac adapters are also called electricity vampires as they use power when there is no load attached to them.

Programmable Power Supply

• This power supply can be regulated from a distant position with the analog or digital interfacing.

• Thre are numerous applications of programmable power supplies such as testing of automated equipment, monitoring of crystal growth, and X-Ray generators.
• Programmable power supplies usually used in an integral microcomputer to regulate and observe the power supply process.

UPS

• The UPS stands for uninterruptible power supply there are 2 input sources that provide the power to the UPS at the same time.
• It gets power from the main source and also charges the battery connected with it.
• If some time main supply is off than within very less time UPS start power from the battery to load.
• In some applications, continuous power is required so the switching process should be high normally quasi-standard is four milliseconds but in some application is not fast.
•  UPS is normally installed in hospitals, call centers, telephones exchanges, etc for continuity of the process.

High-Voltage Power Supply

• The power supply whose output is more than hundreds and thousands of volts is called high volts power supply.

• To provide protection from the flashing, damaging of insulation, special types of output connectors are used at an output of these power supplies.
• For voltage above twenty kilovolts, federal standard connectors used while for SHV connectors uses for less voltage.
• Some types of these power supplies also used to control distant outputs due to features of analog or digital interfacing.
• These power supplies normally used in X-ray machines, electron microscope, electrostatics for focusing the beam of ions and electrons.

Bipolar Power Supply

• If we make a Cartesian plane between current and voltage than in all four quadrants bipolar supply functions. It means produces positive and negative voltage and currents for regulations.
• When its output is regulated with the less level analog signal than it called the Operational amplifier having less bandwidth with a large value of output.
• It used in magnetic devices for scientific applications.

Application of Power Supply

• The power supply is the basic part of any electronic device so it used in numerous industrial machines. So let’s discuss their different applications with the detail.

Computer

• The power supply used in computers is a switch-mode power supply that transforms AC signal coming from main into dc voltages.
• These power supplies preferred over the linear power supply due to less price, high efficiency and less weight.

Electric Vehicles

• Electrical vehicles operate on electricity. In these vehicles, different power supplies are used to provide power.

Aircraft

• In different aircraft, DC to DC or AC to DC power supplies is used for usage of power.
• The frequency of these power supplies is four hundred hertz.

Medical Instruments

• Different medical instruments such as ventilators, infusion pumps, surgical instruments operate on the power supply.

So friends that are complete post about the power supply, if you have any queries about this post ask in comments. See you in the next interesting post. Have a good day.