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A Cycloconverter is a device which converts ac power at one frequency into ac power at different frequency without an intermediate dc link. A Cycloconverter is also called a cycle converter or frequency changer. In Cycloconverter, the output frequency and voltage can be changed independently and continuously with the help of control circuits.



In which frequency obtained at the output is less than the supply frequency.


In this output, frequency is more than supply frequency.

Application of cycloconverter

A cycloconverter is used to control the speed of the induction motor or synchronous motor. It is basically used to provide a variable frequency power from a fixed an input power or a fixed frequency. ower from a Variable frequency power. Other applications of a cycloconverter include:
  1. Induction heating

  2. Connecting two grid, operating at different frequencies.

  3. Used in variable speed constant frequency system (V SCF system), where constant frequency output is obtained from variable speed alternator. 

  4. Static VAR compensator (SVC).

  5. Ruggedness and compactness of cycloconverter make it suitable for power supply in aircraft.

  6. Used in Gearless ball and cement mill drives.

The cycloconverter can convert power from a single-phase supply or a. three-phase supply, producing either a single-phase or three-phase power.

Cycloconverters are classified

  1. Single-phase cycloconverter 

  2. Three-phase cycloconverter 

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