To create a MATLAB Simulation Model for my project, ( Hybrid PV system using Multilevel Inverter )

This dissertation report presents an efficient photovoltaic (PV) generation integrated with multilevel inverter to ensure regulated power at user end. Perturb and observe (PO) algorithm based maximum power point tracking (MPPT) has been utilized to track maximum power for PV applications. However in PV based power generation, control problems arise due to large variation of irradiance round the clock. This problem can be overcome by hybrid PV generation system, i.e., application of secondary power source as battery and fuel cell integrated with PV generation unit.

In this dissertation report performance analysis of standalone hybrid PV, fuel cell and storage battery generation system has been done. The modeling of PV array has been done considering the temperature and sun's irradiance. A MPPT technique has been implemented to track peak power to maximize the generated energy. For this PO algorithm has been used due to its simplicity and robustness. The DC/DC converter, as an integral part of MPPT system, has also been designed. Boost converters using proportional controller (PI) have been designed for PV generation to boost voltage up to 400V. Further this PV system is integrated with fuel cell and battery storage to form a hybrid generation system. The DC output of standalone hybrid PV-SOFC-Battery generation system is inverted by a single-phase multilevel converter. This output of developed standalone hybrid PV-SOFC-Battery generation system is used to supply the single-phase load.

The results have been verified with MATLAB/Simulink for different load applications. The simulation results for PVA, SOFC, MPPT, buck converter, boost converter and single -phase inverter has also been verified

Description Rating

Short circuit current ( SC I ) 5 Amp

Open circuit voltage ( OC V ) 45.33 Volt

Current at MPP ( m I ) 4.91 Amp

Voltage at MPP ( m V ) 80.61 Volt

Maximum Power ( m P ) 395.79 Watt

Design Parameters of SOFC

The above table shows the different parameters of SOFC used in the dissertation work. These ratings have been used in the final modeling.

Absolute temperature 1273 K

Initial current 100 A

Faraday’s constant 96.487e6 C/kmol K

Universal gas constant 8314 j/kmol K

Number of cell in series 450

Maximum fuel utilization 0.9

Minimum fuel utilization 0.8

Optimal fuel utilization 0.85

Value of molar constant for hydrogen 8.43e-4 Kmol/s

Value of molar constant for water 2.81e-4 Kmol/s

Value of molar constant for oxygen 2.52e-3 Kmol/s

Response time for hydrogen flow 26.1 S

Response time for water flow 78.3 S

Response time for oxygen flow 2.91 S

Ohmic losses per cell 3.281e-004 Ohm

Electrical Response time .8 S

Fuel processer response time 5 S