Q1. Find the Thevenin equivalent circuit when you view the system from Bus i and Bus j. Assume that at normal operating condition the voltage phasors of Bus i and Bus j are given: V-i and V-j. Also assume the system's Ybus matrix is known.
Q2. A 3Φ load draws 200 kW at a PF of 0.707 lagging from a 440-V line. In parallel is a 3-phi capacitor bank that supplies 50 kVAr. Find the resultant power factor and current (magnitude) into the parallel combination.
Q3. The system shown in Fig. is balanced 4Φ. Use per phase analysis to find I-a, I-b, I-c, and I-d. Note: We need to find a "star" equivalent for the set of voltages.
Q4. The system shown in Fig. is balanced. Assume that ZL = j10 and Zc = -j10. Find I-a, I-cap, and S3Φload.
Q5. In Fig, assume that E-a = √2 ∠45o, E-b = 1∠-90o, E-c = 1∠180o, and I-a= 1∠-10o. The load is symmetrical and Z is not given. The sources are not balanced, but we note that E-a + E-b + E-c = 0. Find S3Φload.