A high-voltage direct current (HVDC) electric power transmission system uses direct current (DC) for electric power transmission, in contrast with the more common alternating current (AC) transmission systems.
A power inverter, inverter, or invertor is a power electronic device or circuitry that changes direct current (DC) to alternating current (AC). The resulting AC frequency obtained depends on the particular device employed. Inverters do the opposite of rectifiers which were originally large electromechanical devices converting AC to DC.
Power electronics is the application of electronics to the control and conversion of electric power.
A motor–generator is a device for converting electrical power to another form. Motor–generator sets are used to convert frequency, voltage, or phase of power. They may also be used to isolate electrical loads from the electrical power supply line. Large motor–generators were widely used to convert industrial amounts of power while smaller motor–generators were used to convert battery power to higher DC voltages.
A rotary converter is a type of electrical machine which acts as a mechanical rectifier, inverter or frequency converter.
Danfoss is a Danish multinational company, based in Denmark, with more than 41,928 employees globally. Danfoss was founded in 1933 by engineer Mads Clausen.
A variable-frequency drive is a type of AC motor drive that controls speed and torque by varying the frequency of the input electricity. Depending on its topology, it controls the associated voltage or current variation.
A frequency changer or frequency converter is an electronic or electromechanical device that converts alternating current (AC) of one frequency to alternating current of another frequency. The device may also change the voltage, but if it does, that is incidental to its principal purpose, since voltage conversion of alternating current is much easier to achieve than frequency conversion.
This is an alphabetical list of articles pertaining specifically to electrical and electronics engineering. For a thematic list, please see List of electrical engineering topics. For a broad overview of engineering, see List of engineering topics. For biographies, see List of engineers.
Doubly fed electric machines, also slip-ring generators, are electric motors or electric generators, where both the field magnet windings and armature windings are separately connected to equipment outside the machine.
According to data from the US Energy Information Administration, renewable energy accounted for 8.4% of total primary energy production and 21% of total utility-scale electricity generation in the United States in 2022.
A variable-speed drive (VSD) air compressor is an air compressor that takes advantage of variable-speed drive technology. This type of compressor uses a special drive to control the speed (RPM) of the unit, which in turn saves energy compared to a fixed speed equivalent. This is done to improve the efficiency of the compressor as varying the displacement or compression ratio of a compressor generally introduces significant inefficiency, or is impractical to implement.
The Central Intelligence Agency (CIA) has repeatedly intervened in the internal affairs of Iran, from the Mosaddegh coup of 1953 to the present day. The CIA is said to have collaborated with the last Shah, Mohammad Reza Pahlavi. Its personnel may have been involved in the Iran-Contra affair of the 1980s. More recently in 2007-8 CIA operatives were claimed to be supporting the Sunni terrorist group Jundallah against Iran, but these claims were refuted by a later investigation.
Semikron is a German-based independent manufacturer of power semiconductor components. The company was founded in 1951 by Dr. Friedrich Josef Martin in Nuremberg. In 2019, the company had a staff of more than 3,000 people in 24 subsidiaries (world-wide) with production sites in Germany, Brazil, China, France, India, Italy, Slovakia, and the USA.
A solid-state AC-to-AC converter converts an AC waveform to another AC waveform, where the output voltage and frequency can be set arbitrarily.
There is a large array of stakeholders that provide services through electricity generation, transmission, distribution and marketing for industrial, commercial, public and residential customers in the United States. It also includes many public institutions that regulate the sector. In 1996, there were 3,195 electric utilities in the United States, of which fewer than 1,000 were engaged in power generation. This leaves a large number of mostly smaller utilities engaged only in power distribution. There were also 65 power marketers. Of all utilities, 2,020 were publicly owned, 932 were rural electric cooperatives, and 243 were investor-owned utilities. The electricity transmission network is controlled by Independent System Operators or Regional Transmission Organizations, which are not-for-profit organizations that are obliged to provide indiscriminate access to various suppliers to promote competition.
Stuxnet is a malicious computer worm first uncovered in 2010 and thought to have been in development since at least 2005. Stuxnet targets supervisory control and data acquisition (SCADA) systems and is believed to be responsible for causing substantial damage to the nuclear program of Iran. Although neither country has openly admitted responsibility, multiple independent news organizations recognize Stuxnet to be a cyberweapon built jointly by the United States and Israel in a collaborative effort known as Operation Olympic Games. The program, started during the Bush administration, was rapidly expanded within the first months of Barack Obama's presidency.
The electricity sector in Switzerland relies mainly on hydroelectricity, since the Alps cover almost two-thirds of the country's land mass, providing many large mountain lakes and artificial reservoirs suited for hydro power. In addition, the water masses drained from the Swiss Alps are intensively used by run-of-the-river hydroelectricity (ROR). With 9,052 kWh per person in 2008, the country's electricity consumption is relatively high and was 22% above the European Union's average.
The DC distribution system has been proposed, as a replacement for the present AC power distribution system for ships with electric propulsion.
This glossary of electrical and electronics engineering is a list of definitions of terms and concepts related specifically to electrical engineering and electronics engineering. For terms related to engineering in general, see Glossary of engineering.
€403.0 million (2013) [1]