A 10 kV, 5.5 kA switch is constructed using 60 thyristors connected in series-parallel arrays. Each thyristor is rated for 1.2 kV and 1 kA, utilizing 6 parallel paths. Calculate the switch efficiency______________________?
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Answer: A. 76.3 %
Explanation
Switch efficiency calculation compares aggregate component ratings against the total system capacity requirements. Dividing total effective utilized capacity by installed component capacity yields the precise percentage. Array calculations factor in series and parallel paths to determine accurate power handling efficiency. Series-parallel thyristor arrays handle high voltage and current demands exceeding individual device limits. Switch efficiency measures how effectively semiconductor device ratings are utilized within a converter array. Overdesigned arrays lower overall efficiency while underdesigned arrays risk component breakdown failures.
High-voltage power conversion equipment requires careful semiconductor array sizing for optimal economics. Engineers balance redundancy and component utilization when designing large industrial power switches. Accurate efficiency calculations ensure reliable operation in critical power transmission infrastructure. Alternative percentage figures arise from miscalculating the required series-parallel component multiplier ratios. Incorrect assumptions about string voltage distributions yield erroneous efficiency calculations like 91.6 percent. Other mathematical combinations fail to reflect the precise device rating-to-load capacity ratio.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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