Laddered multilevel inverters used in solar panel system

• Main Author: Chen, Junyan
• Other Authors: Luo Fang Lin
• Format: Final Year Project
• Language: English
• Published: 2012
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Power electronics
• Online Access: http://hdl.handle.net/10356/49554
• Institution: Nanyang Technological University

Solar energy is the primary source of renewable energy in all over the world. The photovoltaic cells can convert the solar energy directly into DC. For the large photovoltaic systems which are connected with the grid, they need inverters to convert the direct current to alternative current.In the project new kinds of multilevel inverters were introduced – laddered inverters. Laddered inverters can handle the task successfully and have several advantages over the conventional inverters. Similar to the multilevel inverters like diode-clamped inverters, the laddered inverters can output a waveform that contains various voltage levels.Seven kinds of laddered inverters and their topologies are discussed in the project. And a simple contrast is made between the laddered inverters and the multilevel inverters like diode-clamped inverters. Simulations are achieved by the software – PSIM 8.0. The output waveform can be easily observed and the harmonic contents are illustrated by using the Fast Fourier Transform (FFT). To get the least total harmonic distortion, Matlab software is used to calculate the best firing angles.