advertisement

ECE 4300/5300 ELECTRIC POWER SYSTEMS SPRING 2016 HW #5 DUE: 03/28/2016 NOTE**: There are answers to some of the problems at the end of the book. To get full credit, you must show how you got your answers or you will receive ZERO score. 1. Power System Analysis by Saadat: Problem #6.1 pp. 286. 2. Consider the six-bus system of Fig. P2.1 with line impedances and admittances shown in Table P2.1. (a) Convert the network impedances to admittances. (b) Determine the bus admittance matrix (Ybus). (c) Modify the Ybus if a line with reactance j0.01 p.u. is added between buses 1 and 5. 6 3. 3 2 1 Table P2.1 Line Bus to bus 1–2 1–6 2–4 2-3 3–4 4-5 5-6 5 Fig. P2.1 4 Series Reactance p.u. j0.04 j0.06 j0.03 j0.02 j0.08 j0.06 j0.05 The Fig. P3.1 shows the one-line diagram of a simple four-bus power system. Take ground as a reference. (a) Find the bus incidence matrix A for the four-bus power system. (b) Find the primitive admittance matrix for the system. It is given that all the lines are characterized by a series impedance of 0.1 + j0.7 Ω/km and a shunt admittance of j0.35 x 10-5 S/km. Lines are rated at 220 kV. (c) Find the admittance matrix for the system in per unit. Use the base values 220 kV and 100 MVA. Express all impedances and admittances in per unit. 1 100 km 2 150 km 110 km 100 km 120 km 4 Fig. P3.1 3