Electrical Engineering / Subcategory
Power Systems
Power systems calculators and formulas for real, apparent, and reactive power in AC/DC circuits. Includes power factor, three-phase power, and load calculations for electrical systems.
18Formulas
All levels Difficulty
Updated Jul 2026
← All Electrical Engineering (151) Power Systems (18)
Fundamental
Short-Circuit Current
I_sc = V / Z_sc
Fundamental
Fault Level (MVA)
MVA_fault = kV² / Z
Fundamental
Power Factor Correction Capacitor Sizing
Q_C = P(tan θ₁ − tan θ₂)
Fundamental
Transformer kVA Rating
kVA = (V × I) / 1000
Fundamental
Star-Delta Line-Phase Relationship
Star: V_L=√3·V_ph, I_L=I_ph | Delta: V_L=V_ph, I_L=√3·I_ph
Fundamental
Power in kW (Three Phase)
P(kW) = (√3 × V_L × I_L × cos θ) / 1000
Fundamental
Power in kW (Single Phase)
P(kW) = (V × I × cos θ) / 1000
Fundamental
Base Impedance (Per-Unit System)
Z_base = V_base² / S_base
Fundamental
Line Losses
P_loss = I²·R
Fundamental
Voltage Regulation
VR = (V_NL − V_FL)/V_FL × 100%
Fundamental
Electrical Efficiency
η = (P_out / P_in) × 100%
Fundamental
Transformer Power Conservation
V₁·I₁ = V₂·I₂
Fundamental
Transformer Turns Ratio
V₁/V₂ = N₁/N₂
Fundamental
Power Triangle Relation
S² = P² + Q²
Fundamental
Complex Power
S = P + jQ
Fundamental
Three-Phase Power (Line Values)
P = √3·V_L·I_L·cos θ
Fundamental
Apparent Power (AC)
S = V · I*
Fundamental
Electrical Power (DC)
P = V · I