Design and Implementation of One kilowatt Capacity Single Phase Grid Tie Photovoltaic Inverter Saurav Das School of Engineering & Computer Science Independent University Bangladesh Dhaka, Bangladesh E-mail:saurav.iubian@gmail.com Khosru M Salim School of Engineering & Computer Science Independent University Bangladesh Dhaka, Bangladesh E-mail:khosrumdsalim@yahoo.com Abstract—This Paper is aimed to present the design and implementation of a one kilowatt capacity single phase grid tie photovoltaic inverter. The proposed design and simulation process of this system is in PSIM simulation environment. The reason for choosing the software PSIM is that it provides the solar module facilities. For single phase grid tie inverter design some special types of consideration, like reference voltage creation to synchronise the inverter’s output with grid, PWM (Pulse Width Modulation) signal creation by comparing the reference and triangular wave, is designed and simulated precisely. According to the PWM pulses, the solar module provided DC voltage is switched by using single phase bridge inverter circuit. After filtering and matching the inverter’s AC output wave’s amplitude and frequency with grid, this AC power is given to the grid by using isolation transformer. All of these fundamental criteria of an inverter are met in this inverter design. After analysing the simulated output a hardware prototype is also implemented. In hardware prototype, according to the reference signal, PIC18F4431 microcontroller is used for generating the PWM pulses. These PWM pulses act as the switching controlling pulses for IGBT (Insulated Gate Bipolar Transistor). Keywords: Grid Tie, Photovoltaic, Inverter, PWM, MPPT. I. INTRODUCTION Now we are living in a modern age where almost everything is run by Electrical Energy. For greater industrialization and population growth the Energy demand rate is now increasing day by day. In International Energy Outlook 2009 by the U.S Energy Information Administration, predicted that the rate of generation of global electricity will be increased to 23.2 trillion kWh in 2015, and for the next five years it will increase to 31.8 trillion kWh. The conventional electricity generation by burning fossil fuels like coal, gas, oil is unable to meet up this rapidly increasing electricity demand. The reason is that these fossil fuels are treated as natural resources whose amount is very much limited and is decreasing day by day. On the other side burning the fossil fuel emits toxic gas like carbon dioxide which is harmful for our health and environment. The economically and environmentally suitable solution to fulfil the energy demand is the Renewable Energy [1].Among all forms of Renewable Energy such as solar energy, wind energy, biomass energy, tidal energy, energy from the rice husk, the popularity of solar energy is increasing. To fulfil the Energy demand and to ensure proper utilization of Energy, the photovoltaic inverter is a good solution. The word “Photovoltaic” means converting light energy to electrical energy. For getting electrical energy from the solar energy, the PV (Photovoltaic) module is used. The energy produced in this way is DC power. But to convert the DC power to AC power, Inverters are used. There are two types of inverters. One is stand-alone and the other type is grid-connected. Stand-alone inverter is mainly used in rural areas or in those areas where the electricity is not available. Large capacity batteries are used for storing the energy produced by the solar panel. On the other hand the grid connected inverter is installed in that type of areas where the grid is available and is able to accept the energy from the photovoltaic system [2].Grid connected inverter converts the DC power into that type of AC power whose voltage’s magnitude, phase and frequency is exactly same as the grid’s provided AC power. In this gird tie photovoltaic system the cost of PV module plays an important part .According to the survey report presented by the IEA-PVPS, in 2011 the average price per watt of PV module was 1.38 USD. In 2012 the average price per watt of PV module was reduced to 1.16 USD, which indicates the reduction cost is about 15.9%. In some countries, at the end of the year 2012 the average price per watt of PV module went below 0.6 USD [3]. Due to the decreasing price of PV modules, availability of sun shine, no cost for fuel, low maintenance cost, reliability, providing noise and pollution free environment in 2010 above 78% of world market was for that type of applications which are related with Grid Connected Photovoltaic Inverter system [4]. II. OVERVIEW OF THE SYSTEM The system overview of the Grid tie photovoltaic inverter is shown in Fig.1. Fig 1: Block diagram of the Grid Tie Inverter system Saurav Das and Khosru M. Salim. "Design and implementation of one kilowatt capacity single phase grid tie photovoltaic inverter." In Electrical Engineering and Information & Communication Technology (ICEEICT), 2014 International Conference on, pp. 1-5. IEEE, 2014. DOI: 10.1109/ICEEICT.2014.6919081