AY 2022 23 Test 2 Numerical part with solutions

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ELECTRIC CONVERSION FROM GREEN SOURCES OF ENERGY Prof. Alberto Dolara ©Prof. Alberto Dolara – All rights reserverd 1 Numerical exercise 1 < 20 July 2023 > The hybrid power plant sketched in the figure on the right consists of: ► a PhotoVoltaic (PV) generator. ► a Wind Generator (WG) based on Permanent Magnet Synchronous Generator (PMSG). Each sub-generator is equipped with its own Battery Energy Storage System (BESS). The hybrid power plant is connected to the national grid (three- phase) by means of a 15/ 0.4 kV Low Voltage / Medium Voltage transformer. The national grid is assumed to be an infinite short circuit power grid, and its rated voltage is 15 kV. PV Generator ratings: ► PV rated power, P PV 5 00 kW ► PV voltage range, VPV from 300 V to 950 V ► PV power processor DC bus voltage, VDCbus,PV kept constant at 800 V Wind Turbine ratings: ► Wind turbine Maximum power, PW 5 00 kW ► Wind turbine output voltage range, VW from 200 V to 600 V (RMS, line-to-line) ► Wind turbine power processor DC bus voltage, VDCbus,WT kept constant at 1000 V BESS PV and BESS WG converters and batteries: ► Rated power, PBESS 5 00 kW ► Battery side voltage range, VBESS from 460 V to 540 V ► Open circuit voltage, VOC(SOC) V OC(SOC) = 480 + SOC · 40 V (SOC = State Of Charge; 0 ≤ SOC ≤ 1) ► Equivalent internal resistance, Rbatt 20 mΩ Preliminary Definitions and Calculations 1. Choose the type of DC/DC converter suitable for interfacing the PV generator to the PV power processor DC bus, then calculate the minimum and maximum value of the control signal. 2. Choose the type of AC/DC converter suitable for interfacing the PMSG of the wind turbine to the WT power processor DC bus; it is required that the PMSG operates at unity power factor in any operating conditions. 3. Choose the type of DC/DC…