3.49 Consider the single-line diagram of a power system shown in Figure 3.40 with equip-

ment ratings given below:

FIGURE 3.40

One-line diagram for

Problem 3.49

Generator G₁:

Generator G₂:

3-phase. A-Y transformer T₁:

3-phase Y-A transformer T₂:

Load:

G₁

Choose a base of 100 MVA for the system and 132-kV base in the transmission-line

circuit. Let the load be modeled as a parallel combination of resistance and induc-

tance. Neglect transformer phase shifts.

Draw a per-phase equivalent circuit of the system showing all impedances in per unit.

T₁

или

50 MVA, 13.2 kV, x = 0.15 pu

20 MVA, 13.8 kV, x = 0.15 pu

80-MVA, 13.2-A/165 Y kV-X=-0-1-pur-

40 MVA, 165 Y/13.8 A kV, X = 0.1 pu

40 MVA, 0.8 PF lagging, operating at 150 kV

(50+/200)92

(25+j100)| (25+j100)

Load

T₂

t}}

mm

G₂