Performance Analysis of 3kW Residential Grid-Connected Photovoltaic System with Microinverter Topology using System Advisor Model

Abstract

Abstract: Grid connected rooftop PV systems are the most common form of solar energy utilization that helps home owners to reduce carbon footprint and save money in utility bills. This project focuses on the design and modelling of a 3KW residential PV system connected to a 240V single phase grid. The purpose of this study was to conduct an independent experiment on a photovoltaic system with microinverters, to determine their performance characteristics in shaded and unshaded conditions. The systems have fixed tilt angle and fixed azimuth angle. In order to analyse the performance of the systems, the Energy Yield, Performance Ratio, Capacity factor and Annual Energy have been used. This allowed to obtain reliable metrics even with different Irradiance values and different Peak Powers. In the conventional central inverters, several strings of PV modules are combined in order to achieve the power required from the inverter to operate. Strings are connected in parallel and then these strings are led to the inverter after running several meters of DC cables. These cables are often very thick and as a result are very expensive while at the same time, they add losses to the overall system. On the other hand, AC cables are much less expensive and they have fewer losses. A residential system was designed in SAM using specific weather data. The simulation results supported the fact that micro inverters perform well in both shaded and non-shaded conditions. A significant advantage of Micro Inverters is the avoidance of shading losses and mismatch among different PV technologies which consists a great challenge on PV installations. The String Inverter system produced an annual energy of 4763 kWh in the first year with no shading and 4286 kWh in the first year with shading losses. Keywords: Inverters, Photovoltaic cells, Photovoltaic systems, Solar energy, Solar panels.