Question

Styles AC Bus Local Loads T: OC Bus PV Generating DC/AC Station Zline Local Power Grid Inverter T1 T2 Figure Q2 In the microgrid in figure Q2, a solar PV station and the local power grid supply a series of local loads The PV generating station is rated at 2 MW and is operating at unity power factor. The PV station internal impedance is purely resistive equal to 50% based on its own rating of 2 MVA. The inverter DC side voltage is 700 V DC, the inverter AC side voltage 415 V AC and the step-up transformer T1 is 415 V/23 kV. The power local power grid is 69kV with negligible short circuit reactance. The transmission line impedance Zline is 3+j5 ohms per phase at 23 kV. The transformer details are: Transformer T1: 3 MVA, 415 V/23 kV, 7.59% reactance, 25 MVA, 69 23 kV, 8% reactance. Transformer T2 1 MVA at 23 kV at 0.9 PF lagging Local loads are Assume a base power of 10 MVA Develop the following The per unit model for the power flow studies 1. The per unit model for short circuit studies 2 Also calculate 3. The real and reactive power flow from the grid connection, when the PV generating station is producing 2.5 MVA at unity power factor with a line voltage regulated to 415 V on the inverter AC terminals.

Answer 1

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