Power electronics is the technology associated with the efficient conversion, control and conditioning of electric power by static means from its available input form into the desired electrical output form.
Power electronic converters can be found wherever there is a need to modify the electrical energy form (i.e. modify its voltage, current or frequency.) With “classical” electronics, electrical currents and voltage are used to carry information, whereas with power electronics, they carry power. Some examples of uses for power electronic systems are DC/DC converters used in many mobile devices, such as cell phones or PDAs, and AC/DC converters in computers and televisions. Large scale power electronics are used to control hundreds of megawatt of power flow across our nation.
Electric power systems are comprised of components that produce electrical energy and transmit this energy to consumers. A modern electric power system has mainly six main components: 1) power plants which generate electric power, 2) transformers which raise or lower the voltages as needed, 3) transmission lines to carry power, 4) substations at which the voltage is stepped down for carrying power over the distribution lines, 5) distribution lines, and 6) distribution transformers which lower the voltage to the level needed for the consumer equipment. The production and transmission of electricity is relatively efficient and inexpensive, although unlike other forms of energy, electricity is not easily stored, and thus, must be produced based on the demand.