A thyristor string is made of a no. of SCR connected in series and parallel. The string have volume and current of 11 KV and 4 KA. The voltage and current rating of available SCRs are 1800 V and 1000 A. For a string efficiency of 90 % let the number of SCRs in series and parallel are a and b respectively. Then the value of a and b will be_____________?
Correct answer: C. 7, 5
- A. 5, 7
- B. 4, 6
- C. 7, 5
- D. 6, 4
Explanation
The required series count is 11/(1.8 × 0.9) = 6.79, so 7 SCRs are needed in series. The parallel count is 4/(1 × 0.9) = 4.44, so 5 parallel paths are required.
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