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Q85HardInverters

एक सिंगल-फेज़ फुल-ब्रिज VSI 48 V बैटरी से पोषित है और 10 Ω प्रतिरोधी लोड को शक्ति देता है। स्क्वेयर वेव स्विचिंग का उपयोग करते हुए सत्यापित कीजिए
1. मूल आउटपुट वोल्टेज का RMS मान 43.2 V है।
2. मूल घटक द्वारा दी गई शक्ति 186.6 W है।
3. लोड को दी गई कुल शक्ति 230.4 W है।
कौन-से कथन सही हैं?

उत्तर और चरणबद्ध हल
सही उत्तर: D. 1, 2 और 3
संक्षिप्त व्याख्या

D — 1, 2 और 3। स्क्वेयर-वेव का कुल RMS = 48 V, कुल शक्ति = 48²/10 = 230.4 W। मूल RMS = 4Vdc/(π√2) ≈ 43.2 V और मूल शक्ति ≈ 43.2²/10 = 186.6 W।

विस्तृत हल (मूल भाषा में)

Statement-wise Verification

  • Statement 1 - Correct.
    RMS value of fundamental output voltage is 43.2 V.
    Fundamental RMS=4Vdc/(π√2)≈43.2 V and fundamental power≈43.2²/10=186.6 W.
  • Statement 2 - Correct.
    Power delivered by the fundamental component is 186.6 W.
    Fundamental RMS=4Vdc/(π√2)≈43.2 V and fundamental power≈43.2²/10=186.6 W.
  • Statement 3 - Correct.
    Total power delivered to the load is 230.4 W.
    Full-bridge square-wave total RMS voltage is 48 V, so total load power=48²/10=230.4 W.

Core Concept

Three-phase voltage-source inverters can be operated with 120° or 180° conduction sequences. In 120° conduction, each switch is on for 120° and only two devices conduct at a time, leaving one phase disconnected for intervals. In 180° conduction, three devices conduct at a time and the fundamental output is higher; the floating star neutral can shift relative to the DC midpoint.

Formula / Key Relationship

Conduction duration: 120°→two switches at a time; 180°→three switches at a time.

Step-by-Step Check

Full-bridge square-wave total RMS voltage is 48 V, so total load power=48²/10=230.4 W. Fundamental RMS=4Vdc/(π√2)≈43.2 V and fundamental power≈43.2²/10=186.6 W.

Why the Other Options Are Wrong

Option A is incorrect because it omits correct statement(s) 3. Option B is incorrect because it omits correct statement(s) 1. Option C is incorrect because it omits correct statement(s) 2.

Exam Shortcut / Approach

Track pole voltage and load-neutral voltage separately.

Common Mistake

Balanced load does not force the floating neutral to the DC midpoint at every switching state.

Quick Revision

Square-Wave Fundamental and Load Power is linked with Single-Phase Full-Bridge VSI, Inverters and Power Electronics. Track pole voltage and load-neutral voltage separately.

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