IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 _______________________________________________________________________________________ Volume: 04 Issue: 04 | April-2015, Available @ http://www.ijret.org 706 LCLR FILTER DESIGN AND MODELLING FOR HARMONIC MITIGATION IN INTERCONNECTED MICRO GRID SYSTEM D. S. Sargar 1 , C. L. Bhattar 2 1 P.G. Scholar, Department of Electrical Engineering, Rajarambapu Institute of Technology, Maharashtra, India 2 Assistant Professor, Department of Electrical Engineering, Rajarambapu Institute of Technology, Maharashtra, India Abstract Today many people are attracted towards distribution generation (DG) because of low energy cost power supply, local generation, highly reliable system, supply with good power quality. Increasing attention and investment in renewable energy that is DG energy sources give rise to rapid development of high penetration renewable energy sources like solar energy, wind energy, hydro energy. Out of this most important and best is the solar energy. There are multiple ways to interface PV arrays with the power grid, but in there is problem of power quality. Today’s important concern of the power system is the power quality in case of renewable energy sources. The power quality improvement in the interconnected micro grid systems and grid interconnection with Distribution Generation (DGs) is the challenging task and to overcome the power quality problem passive filters are the best and cost effective solution. In this paper the LCLR filter is implemented between inverter and grid. The complete system consists of photovoltaic cell (PV), DC-DC boost converter, DC-AC inverter, LCLR filter and the grid. This paper also consists of complete MATLAB simulation of PV cell, DC-DC boost converter and inverter with LCLR filter. Key Words: Renewable energy, PV module, DC-DC boost converter, DGs, LCLR filter, power quality, micro grid (MG) and THD --------------------------------------------------------------------***---------------------------------------------------------------------- 1. INTRODUCTION Nowadays the cost of fuel increased due to increasing demand of fuel and use of it, but the fuels are exhaustible in nature so in the future they will be completely vanished in one day. Other reasons are the tremendous increase in population and global warming. The best solution for to reduce the fuel cost and reduce unlimited use of fuel and to save the fuel for future is the use of renewable energy sources for the generation of electrical energy. Some best renewable energy sources for generation of electricity are: (1) Wind energy (2) solar energy (3) Tidal energy (4) Hydro energy [1]. The distribution generation (DGs) means the use of renewable energy sources for generation of electricity and electricity generation is local and own generation. In these the solar energy and wind energy sources are the very popular energy sources because of its availability and suitability. That is in the distribution system electrical energy is generated using wind mill, solar panel with DC- DC converter and DC-AC converter i.e. inverter with its suitable controlling system [1]. The main objectives of use renewable energy sources are: i) provide low cost energy with local generation ii) Reduce the cost of conventional energy sources. iii) Provide good quality power supply. The power quality is obtained using the various power quality improvement devices and equipment’s like DSTATCOM (distribution static compensation), DVR (dynamic voltage restorer), filters (active and passive), and zigzag transformers, etc. For the grid interconnection of renewable energy sources with power grid or micro grid is done using inductor in past cases [2] and in recently LCL (Inductor (L)- Capacitor (C)- Inductor (L)) filters are used [2]-[5]. The higher order harmonic attenuation of LCL filter allows the use of lower order switching frequencies to find the harmonic limitations and these harmonic constraints are defined by IEEE standards. IEEE 1233 standard is for power quality definitions [6]. IEEE 519 standard is for harmonic control in electrical power system [7]. The higher-order LCLR filter has been used in place of the traditional single L i.e. only one inductor in series with line for getting the ripple free the output currents at output of the inverter which is formed by using IGBTs or MOSFETs as power electronic devices. The LCLR filter achieves the higher harmonic reduction along with simple design, the overall weight and size of the LCLR filter is reduced due to appropriate design and modelling. In addition LCLR filter does not produce very high voltage drop across it. LCLR filters have been used in between inverters connected with renewable energy sources with pulse width modulation techniques (PWM) for inverters. In this paper detailed description about LCLR filter modeling, designing procedure is given. The objective of this paper is to carry out the detailed study about modeling and designing of LCLR filter for inverter with renewable energy sources as solar (PV panel). The MATLAB simulation of PV model with boost converter and full bridge inverter with LCLR filter is done with MATLAB Simulink software. The proposed block diagram is shown in fig-1.