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A frequency changer or frequency converter is an electronic 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. // Electronics is the study of electron mechanics. ...
City lights viewed in a motion blurred exposure. ...
City lights viewed in a motion blurred exposure. ...
FreQuency is a music video game developed by Harmonix and published by SCEI. It was released in November 2001. ...
City lights viewed in a motion blurred exposure. ...
International safety symbol Caution, risk of electric shock (ISO 3864), colloquially known as high voltage symbol. ...
Traditionally, these devices were built out of electromechanical components such as motor-generator sets or rotary converters. But with the advent of solid state electronics, it has become possible to build completely electronic frequency changers. These devices usually consist of a rectifier stage (producing direct current) which is then inverted to produce ac of the desired frequency. The inverter may use thyristors or IGBTs. If voltage conversion is desired, a transformer will usually be included in either the ac input or output circuitry and this transformer may also provide galvanic isolation between the input and output ac circuits. A battery may also be added to the dc circuitry to improve the converter's ride-through of brief outages in the input power. Radio station motor-generator, converting from low to the high voltage power supply. ...
Rotary Converter refers to a class of electrical machinery that was used to convert one form of electrical power into another form. ...
In electronics, solid state circuits are those that do not contain vacuum tubes. ...
AC, half-wave and full wave rectified signals A rectifier is an electrical device, comprising one or more semiconductive devices (such as diodes) or vacuum tubes arranged for converting alternating current to direct current. ...
Direct current (DC or continuous current) is the continuous flow of electricity through a conductor such as a wire from high to low potential. ...
An inverter is a circuit for converting direct current (DC) to alternating current (AC). ...
Circuit symbol for a thyristor The thyristor is a solid-state semiconductor device with four layers of alternating N and P-type material. ...
The Insulated Gate Bipolar Transistor combines the simple gate drive characteristics of the MOSFET with the high current and low saturation voltage capability of bipolar transistors by combining an isolated gate FET for the control input, and a bipolar power transistor as a switch, in a single device. ...
For other uses, see transformers. ...
For other uses, see battery (disambiguation). ...
Frequency changers vary in power-handling capability from a few watts to megawatts. In physics, power (symbol: P) is the rate at which work is performed. ...
The watt (symbol: W) is the SI derived unit of power, equal to one joule per second. ...
Applications
Aside from the obvious application of converting bulk amounts of power from one distribution standard to another, frequency changers are also used to control the speed and the torque of the AC motors. In this application, the most typical frequency converter topology is the three-phase two-level voltage source inverter. The phase voltages are controlled using the power semiconductor switches and pulse width modulation (PWM). Semiconductor switching devices and anti-parallel connected freewheeling diodes form a bridge, which can connect each motor phase to the positive or negative dc-link potential. The PWM changes the connections of the phases between the positive and the negative dc-link potentials so that the fundamental wave voltage has the desired frequency and amplitude. The motor reacts primarily to the fundamental voltage and filters out the effects of the harmonic voltages. The utility frequency is the frequency at which alternating current is transmitted from a power plant to the end user. ...
Rotating magnetic field as a sum of magnetic vectors from 3 phase coils An electric motor converts electrical energy into mechanical energy. ...
Pulse-width modulation of a signal or power source involves the modulation of its duty cycle to either convey information over a communications channel or control the amount of power sent to a load. ...
Pulse-width modulation of a signal or power source involves the modulation of its duty cycle to either convey information over a communications channel or control the amount of power sent to a load. ...
A semiconductor is a solid whose electrical conductivity can be controlled over a wide range, either permanently or dynamically. ...
Types of diodes closeup, showing germanium crystal In electronics, a diode is a component that restricts the direction of movement of charge carriers. ...
Another application is in the aerospace and airline industries. Often airplanes use 400 Hz power so 50 Hz or 60 Hz to 400 Hz frequency converter is needed for use in the ground power unit used to power the airplane while it is on the ground.
Frequency changers are typically used to control the speed of pumps and fans. In many applications significant energy savings are achieved. The most demanding application areas are found on the industrial processing lines, where the control accuracy requirements can be very very high.
Alternate uses Frequency converter may also refer to a much-lower-powered circuit that converts radio frequency signals at one frequency to another frequency. The circuit usually consists of a local oscillator and frequency mixer. The same result was achieved historically by the pentagrid converter. It has been suggested that this article or section be merged with Radio waves. ...
In information theory, a signal is the sequence of states of a communications channel that encodes a message. ...
FreQuency is a music video game developed by Harmonix and published by SCEI. It was released in November 2001. ...
FreQuency is a music video game developed by Harmonix and published by SCEI. It was released in November 2001. ...
The superheterodyne receiver (or to give it its full name, the supersonic heterodyne receiver – usually these days shortened to superhet) was invented by Edwin Armstrong in 1918. ...
In telecommunication, a mixer is a nonlinear circuit or device that accepts as its input two different frequencies and presents at its output (a) a signal equal in frequency to the sum of the frequencies of the input signals, (b) a signal equal in frequency to the difference between the...
NOTE: This article is currently being extensively rewritten and expanded off line. ...
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