MODELLING FOR MULTIPORT CONVERTER - BASED HYBRID POWER SUPPLY USING RENEWABLE ENERGY SOURCE APPLICATIONS

Abstract

This research work deals with the design and modeling of a multiport converter-based hybridpower supply using solar PV for a small village. The village’s maximum power demand is 50kW,consisting of loads in twenty (20) households. The first converter in the proposed multiport systemis a high-frequency isolated DC-DC converter fed with an HVDC link yielding an output voltageof 240VDC. The isolated DC-DC converter uses a medium frequency transformer with primaryand secondary side converters in an input-series output-parallel (ISOP) configuration. Also, theoutput of the first converter is connected to a solar PV and battery system through a buck-boostconverter. The second converter in the system is a solar PV-fed three-phase modular inverterdesigned to have an output AC line voltage of 0.415 kV. A solar PV module with an open circuitvoltage of 85V and a maximum power rating of 415W is used to feed the inverter. Differentscenarios such as changes in load and changes in solar irradiance are used for critically evaluatingthe performances of the system under question. The output voltage THD, current distortions,changes in the converter output voltage, current magnitude, and converter efficiency are used asperformance evaluations of the system under consideration. Simulink/ PLECS (Piecewise LinearElectrical Circuit Simulation) combo simulation platform is used to model and simulate the systemin question. Simulation results showed that the proposed multiport converter system can be a viablealternative toa low-frequency distribution transformer.

Keywords: Multiport converter, MMC, DC-DC converter, Hybrid power Supply, Solar PV.