For a DC-DC Boost Converter, consider the following:
1. It can produce an output voltage lower than the input if the duty cycle is less than 0.5.
2. The switch is subjected to the full output voltage when it is OFF.
3. The output capacitor reduces voltage ripple.
Which of the statements given above is/are correct?
Answer & step-by-step solution
An ideal boost converter in continuous conduction has an output voltage greater than or equal to input for 0≤D<1. The output capacitor supplies load current between energy-transfer intervals and reduces output ripple. Key relation: V_o=V_in/(1−D); ΔI_L≈V_in D/(Lf_s).
Exam focus: For an ideal boost, D=1−Vin/Vo. Common trap: A normal boost converter cannot produce Vo<Vin merely because D<0.5.
Statement-wise Verification
- Statement 1 - Incorrect.
It can produce an output voltage lower than the input if the duty cycle is less than 0.5.
An ideal boost converter has Vo=Vin/(1−D), so Vo cannot be below Vin for 0≤D<1 - Statement 2 - Correct.
The switch is subjected to the full output voltage when it is OFF.
When the switch is off, it must block approximately the output voltage. - Statement 3 - Correct.
The output capacitor reduces voltage ripple.
The output capacitor supplies load current between energy-transfer intervals and reduces output ripple.
Core Concept
An ideal boost converter in continuous conduction has an output voltage greater than or equal to input for 0≤D<1. When the switch is off, it must block approximately the output voltage. The output capacitor supplies load current between energy-transfer intervals and reduces output ripple.
Formula / Key Relationship
V_o=V_in/(1−D); ΔI_L≈V_in D/(Lf_s).
Why the Other Options Are Wrong
Option A is incorrect because it omits correct statement(s) 3. Option B is incorrect because it includes incorrect statement(s) 1 and omits correct statement(s) 3. Option D is incorrect because it includes incorrect statement(s) 1.
Exam Shortcut / Approach
For an ideal boost, D=1−Vin/Vo.
Common Mistake
A normal boost converter cannot produce Vo<Vin merely because D<0.5.
Quick Revision
Boost Conversion Ratio and Switch Stress is linked with Boost Converter, DC-DC Converters and Power Electronics. For an ideal boost, D=1−Vin/Vo.
DC-DC बूस्ट कन्वर्टर के लिए निम्नलिखित पर विचार कीजिए:
1. यदि ड्यूटी साइकिल 0.5 से कम हो तो यह इनपुट से कम आउटपुट वोल्टेज दे सकता है।
2. OFF होने पर स्विच पर पूरा आउटपुट वोल्टेज आता है।
3. आउटपुट संधारित्र वोल्टेज रिपल कम करता है।
ऊपर दिए गए कथनों में से कौन-सा/से सही है/हैं?
उत्तर और चरणबद्ध हल
C — केवल 2 और 3। आदर्श बूस्ट में Vo = Vin/(1 − D) ≥ Vin, इसलिए D < 0.5 पर भी Vo, Vin से कम नहीं होता। OFF अवस्था में स्विच पर Vo आता है और आउटपुट संधारित्र रिपल घटाता है।
विस्तृत हल (मूल भाषा में)
Statement-wise Verification
- Statement 1 - Incorrect.
It can produce an output voltage lower than the input if the duty cycle is less than 0.5.
An ideal boost converter has Vo=Vin/(1−D), so Vo cannot be below Vin for 0≤D<1 - Statement 2 - Correct.
The switch is subjected to the full output voltage when it is OFF.
When the switch is off, it must block approximately the output voltage. - Statement 3 - Correct.
The output capacitor reduces voltage ripple.
The output capacitor supplies load current between energy-transfer intervals and reduces output ripple.
Core Concept
An ideal boost converter in continuous conduction has an output voltage greater than or equal to input for 0≤D<1. When the switch is off, it must block approximately the output voltage. The output capacitor supplies load current between energy-transfer intervals and reduces output ripple.
Formula / Key Relationship
V_o=V_in/(1−D); ΔI_L≈V_in D/(Lf_s).
Why the Other Options Are Wrong
Option A is incorrect because it omits correct statement(s) 3. Option B is incorrect because it includes incorrect statement(s) 1 and omits correct statement(s) 3. Option D is incorrect because it includes incorrect statement(s) 1.
Exam Shortcut / Approach
For an ideal boost, D=1−Vin/Vo.
Common Mistake
A normal boost converter cannot produce Vo<Vin merely because D<0.5.
Quick Revision
Boost Conversion Ratio and Switch Stress is linked with Boost Converter, DC-DC Converters and Power Electronics. For an ideal boost, D=1−Vin/Vo.
DC-DC બૂસ્ટ કન્વર્ટર માટે નીચેનું ધ્યાનમાં લો:
1. જો ડ્યૂટી સાઇકલ 0.5 થી ઓછી હોય તો તે ઇનપુટ કરતાં ઓછો આઉટપુટ વોલ્ટેજ આપી શકે છે.
2. OFF હોય ત્યારે સ્વિચ પર સંપૂર્ણ આઉટપુટ વોલ્ટેજ આવે છે.
3. આઉટપુટ સંધારક વોલ્ટેજ રિપલ ઘટાડે છે.
ઉપર આપેલાં વિધાનોમાંથી કયું/કયાં સાચું/સાચાં છે?
જવાબ અને પગલાવાર ઉકેલ
C — ફક્ત 2 અને 3. આદર્શ બૂસ્ટમાં Vo = Vin/(1 − D) ≥ Vin, તેથી D < 0.5 પર પણ Vo, Vin કરતાં ઓછો થતો નથી. OFF સ્થિતિમાં સ્વિચ પર Vo આવે છે અને આઉટપુટ સંધારક રિપલ ઘટાડે છે.
વિગતવાર ઉકેલ (મૂળ ભાષામાં)
Statement-wise Verification
- Statement 1 - Incorrect.
It can produce an output voltage lower than the input if the duty cycle is less than 0.5.
An ideal boost converter has Vo=Vin/(1−D), so Vo cannot be below Vin for 0≤D<1 - Statement 2 - Correct.
The switch is subjected to the full output voltage when it is OFF.
When the switch is off, it must block approximately the output voltage. - Statement 3 - Correct.
The output capacitor reduces voltage ripple.
The output capacitor supplies load current between energy-transfer intervals and reduces output ripple.
Core Concept
An ideal boost converter in continuous conduction has an output voltage greater than or equal to input for 0≤D<1. When the switch is off, it must block approximately the output voltage. The output capacitor supplies load current between energy-transfer intervals and reduces output ripple.
Formula / Key Relationship
V_o=V_in/(1−D); ΔI_L≈V_in D/(Lf_s).
Why the Other Options Are Wrong
Option A is incorrect because it omits correct statement(s) 3. Option B is incorrect because it includes incorrect statement(s) 1 and omits correct statement(s) 3. Option D is incorrect because it includes incorrect statement(s) 1.
Exam Shortcut / Approach
For an ideal boost, D=1−Vin/Vo.
Common Mistake
A normal boost converter cannot produce Vo<Vin merely because D<0.5.
Quick Revision
Boost Conversion Ratio and Switch Stress is linked with Boost Converter, DC-DC Converters and Power Electronics. For an ideal boost, D=1−Vin/Vo.
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