Page 70 – Complete Power Electronics Formula Sheet
For GATE / PSU / Interviews – Final Revision
🔹 1️⃣ Controlled Rectifiers
Single Phase Full Converter: Vo = (2Vm/π) cosα
Half Controlled Converter: Vo = (Vm/π)(1 + cosα)
Inversion mode: α > 90°
🔹 2️⃣ DC-DC Converters (CCM)
Buck: Vo = D Vin
Boost: Vo = Vin / (1 − D)
Buck-Boost: Vo = − D Vin / (1 − D)
SEPIC: Vo/Vin = D / (1 − D)
Ćuk: Vo/Vin = − D / (1 − D)
🔹 3️⃣ DCM Gain (Buck-Boost)
Vo/Vin = − (D² R) / (2Lfs)
🔹 4️⃣ Ripple Equations
Inductor Ripple: ΔIL = Vin D / (L fs)
Output Voltage Ripple (Buck): ΔVo = ΔIL / (8Cfs)
🔹 5️⃣ Critical Inductance
Lcritical = R(1 − D)² / (2fs)
🔹 6️⃣ Inverters
Square Wave Fundamental RMS: V1(rms) = (4Vdc) / (Ï€√2)
THD decreases as switching frequency increases
🔹 7️⃣ LC Filter & Control
Natural Frequency: ω₀ = 1 / √(LC)
Quality Factor: Q = R √(C/L)
ESR Zero: ωz = 1 / (RESR × C)
🔹 8️⃣ Device Formulas
MOSFET Conduction Loss: P = I²Rds(on)
Inductor Energy: E = ½ L I²
Capacitor Energy: E = ½ C V²
🔹 9️⃣ Efficiency
η = Pout / Pin
For boost: Pin = Vin × Iin Pout = Vo × Io
Final Exam Checklist
✔ Always check CCM/DCM ✔ Remember polarity of Buck-Boost ✔ Inversion when α > 90° ✔ Natural frequency from LC ✔ Switching frequency reduces ripple ✔ MOSFET → high frequency ✔ IGBT → high voltage
Complete Power Electronics Final Revision – Shaktimatha Learning
.png)
No comments:
Post a Comment