Analysis and measurement of harmonics in power system and power electronic circuits

• Main Author: Tun, Tun.
• Other Authors: Zhang Daming
• Format: Final Year Project
• Language: English
• Published: 2011
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/42766
• Institution: Nanyang Technological University

A new method of analysis is proposed to graphically predict the spectrum envelope of electromagnetic interference (EMI) emitted by power electronics equipment. Relationships between the time-domain (waveforms) and the frequency-domain (spectrum) of some typical EMI signals observed in power converters are pointed out. Special attention is paid to the analysis of the transient functions of EMI signals. It is shown they behave as filtering or “smoothing” functions in the high-frequency part of the spectrum. The Total Harmonic Distortion (THD) can be used to express the quality of a non-sinusoidal wave. It is also an important variable to describe waveform distortion. The harmonic frequency from the multilevel inverter will be focused and discussed. Five-level, Nine-level and eleven-level Cascaded Voltage Source Multilevel Inverter will be built and analyzed on the output voltage waveform. In the mean time, the total harmonic distortion of that output voltage waveform will be monitored using Fast Fourier Transform (FFT). All the experiments and measurements will be used with the Power Simulation software called PSIM.