Question

Problem 6 (20 points) Generate the per-unit admittance matrix for the following power system. All impedances are in per unit quantities and do not include any load or source impedances. Bus 1 Bus 2 om 2192TO ZA = 1+j2 Za = 2+j3 Ze = 1+j0.5 Bus 3 Problem 7(10 points) An individual facility is to receive 480V three-wire delta service. The feeder voltage is 12,000V. If the existing estimated load is 900 kW and you need to plan for 20% growth, what pad mounted, three-phase transformer would you supply? (Use the transformer specifications located in Slide Set 5 [Handout Set 5 revA.pdf] from the COURSE DOCUMENTS area of the Blackboard site and assume a load power factor of 0.9 lagging for planning purposes.) Include the winding information as well as the apparent power rating.

Answer 1

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Here, first by applying nodal analysis at all buses, equations are formed. Then by representing these equations in matrix, Admittance matrix is formed.