Power conversion
Encyclopedia
In electrical engineering
, power conversion has a more specific meaning, namely converting electric power
from one form to another. This could be as simple as a transformer
to change the voltage
of AC
power, but also includes far more complex systems. The term can also refer to a class of electrical machinery that is used to convert one frequency of electrical power
into another frequency.
Power conversion systems often incorporate redundancy
and voltage regulation
.
One way of classifying power conversion systems is according to whether the input and output are alternating current
(AC) or direct current
(DC), thus:
There are also devices and methods to convert between power systems designed for single and three-phase operation.
The standard power frequency varies from country to country, and sometimes within a country. In North America and northern South America it is usually 60 hertz
(Hz), but in many other parts of the world, is usually 50 Hz. Aircraft often use 400 Hz power, so 50 Hz or 60 Hz to 400 Hz frequency conversion is needed for use in the ground power unit used to power the airplane while it is on the ground.
Certain specialized circuits, such as the flyback transformer
for a CRT
, can also be considered power converters.
Electrical engineering
Electrical engineering is a field of engineering that generally deals with the study and application of electricity, electronics and electromagnetism. The field first became an identifiable occupation in the late nineteenth century after commercialization of the electric telegraph and electrical...
, power conversion has a more specific meaning, namely converting electric power
Electric power
Electric power is the rate at which electric energy is transferred by an electric circuit. The SI unit of power is the watt.-Circuits:Electric power, like mechanical power, is represented by the letter P in electrical equations...
from one form to another. This could be as simple as a transformer
Transformer
A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer's coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic field...
to change the voltage
Voltage
Voltage, otherwise known as electrical potential difference or electric tension is the difference in electric potential between two points — or the difference in electric potential energy per unit charge between two points...
of AC
Alternating current
In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....
power, but also includes far more complex systems. The term can also refer to a class of electrical machinery that is used to convert one frequency of electrical power
Electric power
Electric power is the rate at which electric energy is transferred by an electric circuit. The SI unit of power is the watt.-Circuits:Electric power, like mechanical power, is represented by the letter P in electrical equations...
into another frequency.
Power conversion systems often incorporate redundancy
Redundancy (engineering)
In engineering, redundancy is the duplication of critical components or functions of a system with the intention of increasing reliability of the system, usually in the case of a backup or fail-safe....
and voltage regulation
Voltage regulation
In electrical engineering, particularly power engineering, voltage regulation is the ability of a system to provide near constant voltage over a wide range of load conditions.-Electrical power systems:...
.
One way of classifying power conversion systems is according to whether the input and output are alternating current
Alternating current
In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....
(AC) or direct current
Direct current
Direct current is the unidirectional flow of electric charge. Direct current is produced by such sources as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also flow through...
(DC), thus:
|
|
There are also devices and methods to convert between power systems designed for single and three-phase operation.
The standard power frequency varies from country to country, and sometimes within a country. In North America and northern South America it is usually 60 hertz
Hertz
The hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications....
(Hz), but in many other parts of the world, is usually 50 Hz. Aircraft often use 400 Hz power, so 50 Hz or 60 Hz to 400 Hz frequency conversion is needed for use in the ground power unit used to power the airplane while it is on the ground.
Certain specialized circuits, such as the flyback transformer
Flyback transformer
A flyback transformer , also called a line output transformer , is a special transformer, which is used for conversion of energy in electronic circuits. It was initially designed to generate high current sawtooth signals at a relatively high frequency...
for a CRT
Cathode ray tube
The cathode ray tube is a vacuum tube containing an electron gun and a fluorescent screen used to view images. It has a means to accelerate and deflect the electron beam onto the fluorescent screen to create the images. The image may represent electrical waveforms , pictures , radar targets and...
, can also be considered power converters.