Which one of the following frequency converter is
most preferred method for speed control of medium
power rating, three-phase, squirrel cage induction
motor:
(1) Current source inverter
(2) Voltage source inverter
(3) Parallel inverter
(4) Cycloconverter
Answers
workhorse of industry; ... Synchronous Speed – Full Load Rated Speed.
CYCLOCONVERTER
(4) CYCLOCONVERTER is the most preferred method for spped control of medium power rating, three- phase, squirrel cage induction motor.
GETTING TO KNOW MORE ABOUT CYCLOCONVERTER:
* By synthesising the output waveform from segments of the AC supply without an intermediary DC connection, a cycloconverter (CCV) or cycloinverter transforms a constant amplitude, constant frequency AC waveform to another AC waveform of a lower frequency.
* CCVs are classified as either circulating current or blocking mode, with the blocking mode type accounting for the majority of commercial high-power devices.
* While phase-controlled SCR switching devices may be utilised over the whole spectrum of CCVs, TRIAC-based CCVs are essentially reserved for resistive load applications due to their low cost and low power. The output voltage of converters can vary in amplitude and frequency.
* A three-phase CCV's output to input frequency ratio must be less than one-third for circulating current mode CCVs and one-half for blocking mode CCVs.