Date of Award

2007

Degree Type

Thesis Project

Degree Name

Master of Engineering (MEng)

Department

Electrical and Computer Engineering

First Advisor

Bin Wu

Abstract

This project focuses on the topology of multilevel neutral point clamped (NPC)/H-bridge inverters and their modified modulation technique for high-power (megawatts) medium voltage (typically 6000 v) applications. A sinusodial pulse width in-phase disposition modulation is proposed for five-level NPC/H-bridge inverters. The inverter achieves good harmonic performance and low dv/dt in its output voltage waveforms in comparison to the conventional three-level NPC inverter. A seven-level NPC/H-bridge topology and its sinusodial pulse width in-phase disposition modulation are also proposed and investigated, which has better performance than the five-level inverters. Theoretical analysis and computer simulation are carried out for the proposed inverter topologies and algorithms. The output voltage waveforms and harmonic performance are verified by experiments on a five-level NPC/H-bridge inverters.