For the high-frequency choppers, the device that is preferred is
Right Answer is:
A chopper is a static power electronic device that converts the fixed dc input voltage to a variable dc output voltage. It is also known as the DC-DC converter.
- To realize a higher frequency of output voltage ripple, it is customary to use a rectifier with a higher pulse number.
- The use of a rectifier with a higher pulse number results in a low utility factor for thyristors and a relatively high cost.
- On the other hand, a chopper can be operated at comparatively high frequencies.
- When power transistors are employed, frequencies can be higher than 2.5 kHz.
- For low power applications, power MOSFET can be used and the frequency can be higher than 200 kHz.
- The rectifier output voltage and current have a much lower frequency, 100 Hz in the case of a single-phase rectifier and 300 Hz in the case of a three-phase fully controlled rectifier when the a.c. source frequency is 50 Hz.
Summary:- Where high power is involved, an SCR is used as the switch whereas, in medium and low power applications, a transistor is the most suitable.