Critical clearing angle ( \delta_c ) increases with higher inertia, faster fault clearing. 8. Conclusion & Summary Tables (PPT Final Module) Key formulas card:
[ I_a1 = \fracV_fZ_1 + Z_2 + Z_0 + 3Z_f ] [ I_f = 3I_a1 ] power system analysis lecture notes ppt
Generator: 10 MVA, 11 kV, ( X_d'' = 0.12 ) pu. Transformer 10 MVA, 11/132 kV, ( X_t = 0.08 ) pu. Line impedance 20 Ω (on 132 kV). Fault at 132 kV bus. Find ( I_f ) in kA. Critical clearing angle ( \delta_c ) increases with
Fault clears at angle ( \delta_c ). System stable if area ( A_1 ) (accelerating) = area ( A_2 ) (decelerating). ( V_base ) (line-to-line kV).
neglected for overhead lines.
Base quantities: ( S_base ) (3-phase MVA), ( V_base ) (line-to-line kV).