International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395 -0056 Volume: 03 Issue: 04 | Apr-2016 www.irjet.net p-ISSN: 2395-0072 © 2016, IRJET ISO 9001:2008 Certified Journal Page 437 Design and Analysis of Modular Multilevel Inverter for PV-FED Applications Neelesh Pandey, D.Karthikeyan B.Tech, M.Tech, SRM University Chennai-603203 Tamil Nadu B.E,M.E,SRM University Chennai-63203 Tamil ---------------------------------------------------------------------***--------------------------------------------------------------------- Abstract - In this project, the solar fed cascaded multilevel inverter which is used to reduce the number of semiconductor Switches. The 'binary','trinary' and modified multilevel connection' is based on topologies which are suitable for varying input sources from solar photovoltaic’s ȋPVȌ.)n the binary mode, ͸Ns +ͷ − ͷ output voltage levels are obtained by Ns which is the number of the individual inverters. This is achieved by digital logic functions that include counters, flip- flops and logic gates. In trinary mode, 3Ns levels are achieved by corresponding look-up table. The modified multilevel connection intends design in both control and as well as power circuits to provide corresponding output voltage levels by appropriate switching and sequences. Hence, A 15-level inverter, the conventional method requires to 28 switches and in binary mode to 12 switches are needed. In the trinary mode with the same 12 switches 27 levels can be obtained where in modified multilevel connection only have 7 switches are employed to achieve the 15 levels. Now adding one more photovoltaic’s panel and one more switches in modified multilevel connection are employed to achieve 31 levels with the help of binary mode. The advantage of these three designs which is in the reduction of the total harmonic distortion by increasing the levels offer sinusoidal output wave forms, lower EMI, and low switching losses and also reduced THD value. Here Simulations are carried out into the MATLAB/Simulink and comparisons were made. So the experimental results have been implemented by using the PIC Microcontroller in 15 levels only because if here going to implement on 31 levels the wave for become sinusoidal wave form. Key Words: Photovoltic, Modified Multilevel Connection 1. INTRODUCTION Multilevel inverter provides a suitable solution for medium and the high power systems to synthesize an output voltage which can allows a reduction of the harmonic content in the voltage and current wave forms. Renewable energy power which supplied into the utility grid has been paid much attention due to the increase in fossil fuel prices, environmental pollution and the energy demand boom. Among various renewable energy resources such as solar, wind, tidal, geothermal, biomass etc., In the solar photovoltaic system is more attractive and the promising green resource. The solar photovoltaic modules directly can converts the light energy into the electrical energy, but the energy obtained from the photovoltaic module which acts like low voltage DC source and has relatively low conversion efficiency. In order to improve the efficiency and the convert low voltage DC source into usable AC source, the power electronics converters are used to transform the DC into AC. In the simulation results presented in this paper which verifies the operation of proposed in modified multilevel connection topology. 2. PROBLEM STATEMENT To obtain the 15-level inverter, the conventional method requires 28 switches and in the binary mode 12 switches are needed. In the trinary mode with the same 12 switches, 27 levels can be obtained whereas in the modified multilevel connection only 7 switches are employed to achieve the 15 levels. The advantage of these three designs are in the reduction of total number of harmonic distortion by increasing the levels. Fig -1: Existing circuit diagram In this approach, the modification is made in both of the control circuit and the predominately in power circuit to obtain the 15 levels with only seven switches. The addition of diode and the capacitor (1nF) is use to normalize the output within the given interval. Let the photovoltaic array inputs be V1–V3. During the level 1, V1 alone is given as input to the inverter and V2, V3 in OFF condition. Similarly the 15 level is achieved by the controlling the ON/OFF status of the input voltages in the hardware.herw have some of disadvantages