Question
Download Solution PDFIn a chopper circuit, the thyristor is switched OFF at regular intervals by adopting
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFThe correct answer is: 2) Forced commutation
Explanation:
In a chopper circuit, the thyristor (SCR) is used to control the output voltage by rapidly switching ON and OFF. However, unlike transistors or MOSFETs, thyristors cannot turn OFF on their own once triggered; they must be commutated (i.e., brought back to the OFF state).
-
In DC circuits like choppers, there is no natural zero crossing of current (as in AC circuits) to help turn OFF the thyristor.
-
Therefore, natural commutation (which relies on the current going to zero naturally) cannot be used.
-
Instead, a forced commutation technique is used, where an auxiliary circuit forces the current through the thyristor to zero, turning it OFF.
Last updated on Jun 24, 2025
-> ISRO Scientist Engineering apply online 2025 link has been activated (ISRO:ICRB:03(CEPO):2025).
-> A total of 39 vacancies are announced for the ISRO recruitment in Civil, RAC and other disciplines
-> ISRO Scientist Engineering recruitment 2025 notification has been released for 320 vacancies. The last date to fill ISRO application form is June 16 (Advt No. ISRO:ICRB:02(EMC):2025).
-> ISRO Scientist Engineer recruitment 2025 for 31 vacancies has been released.
->ISRO Scientist recruitment 2025 notification has been released.
->The last date to apply for ISRO scientist recruitment 2025 is May 30 ( Advt.No. ISRO:ICRB:01:(EMC):2025).
->Candidates with BE/BTech degree in the respective discipline can only apply for ISRO Scientist recruitment 2025.
-> Candidates can refer ISRO Scientist previous year paper to prepare for the exam.