Three-level Z-source hybrid direct AC-AC power converter topology

Voltage source inverter (VSI) is the traditional power converter used to provide variable voltage and frequency from a fixed voltage supply for adjustable speed drive and many other applications. However, the maximum ac output voltage that can be synthesized by a VSI is limited to the available dc-l...

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Main Author: Effah, Francis Boafo
Format: Thesis (University of Nottingham only)
Language:English
Published: 2014
Subjects:
Online Access:https://eprints.nottingham.ac.uk/14007/
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author Effah, Francis Boafo
author_facet Effah, Francis Boafo
author_sort Effah, Francis Boafo
building Nottingham Research Data Repository
collection Online Access
description Voltage source inverter (VSI) is the traditional power converter used to provide variable voltage and frequency from a fixed voltage supply for adjustable speed drive and many other applications. However, the maximum ac output voltage that can be synthesized by a VSI is limited to the available dc-link voltage. With its unique structure, the Z-source inverter can utilise shoot-through states to boost the output voltage and provides an attractive single-stage dc-ac conversion that is able to buck and boost the voltage. For applications with a variable input voltage, this inverter is a very competitive topology. The same concept can equally be extended to the two-stage matrix converter, where a single Z-source network is inserted in its virtual dc-link. The topology formed is, thus, quite straightforward. Its modulation is, however, non-trivial if advantages like voltage buck-boost flexibility, minimum commutation count, ease of implementation, and sinusoidal input and output quantities are to be attained simultaneously. This thesis presents two novel space vector modulation methods for controlling a three-level Z-source neutral point clamped VSI to enable the use of a boost function. The second of the two space vector modulation methods is then adopted and applied to a three-level, two-stage matrix converter with a Z-source network inserted in its virtual dc-link to increase the voltage transfer ratio beyond the intrinsic 86.6\% limit. Simulation results are supported by experimental verification from two laboratory prototype converters.
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format Thesis (University of Nottingham only)
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language English
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spelling nottingham-140072025-02-28T11:28:22Z https://eprints.nottingham.ac.uk/14007/ Three-level Z-source hybrid direct AC-AC power converter topology Effah, Francis Boafo Voltage source inverter (VSI) is the traditional power converter used to provide variable voltage and frequency from a fixed voltage supply for adjustable speed drive and many other applications. However, the maximum ac output voltage that can be synthesized by a VSI is limited to the available dc-link voltage. With its unique structure, the Z-source inverter can utilise shoot-through states to boost the output voltage and provides an attractive single-stage dc-ac conversion that is able to buck and boost the voltage. For applications with a variable input voltage, this inverter is a very competitive topology. The same concept can equally be extended to the two-stage matrix converter, where a single Z-source network is inserted in its virtual dc-link. The topology formed is, thus, quite straightforward. Its modulation is, however, non-trivial if advantages like voltage buck-boost flexibility, minimum commutation count, ease of implementation, and sinusoidal input and output quantities are to be attained simultaneously. This thesis presents two novel space vector modulation methods for controlling a three-level Z-source neutral point clamped VSI to enable the use of a boost function. The second of the two space vector modulation methods is then adopted and applied to a three-level, two-stage matrix converter with a Z-source network inserted in its virtual dc-link to increase the voltage transfer ratio beyond the intrinsic 86.6\% limit. Simulation results are supported by experimental verification from two laboratory prototype converters. 2014-07-09 Thesis (University of Nottingham only) NonPeerReviewed application/pdf en arr https://eprints.nottingham.ac.uk/14007/1/fbeffah_thesis_final_3rd_Feb_2014.pdf Effah, Francis Boafo (2014) Three-level Z-source hybrid direct AC-AC power converter topology. PhD thesis, University of Nottingham. Z-source Space vector modulation Two-stage matrix converter Voltage source inverter
spellingShingle Z-source
Space vector modulation
Two-stage matrix converter
Voltage source inverter
Effah, Francis Boafo
Three-level Z-source hybrid direct AC-AC power converter topology
title Three-level Z-source hybrid direct AC-AC power converter topology
title_full Three-level Z-source hybrid direct AC-AC power converter topology
title_fullStr Three-level Z-source hybrid direct AC-AC power converter topology
title_full_unstemmed Three-level Z-source hybrid direct AC-AC power converter topology
title_short Three-level Z-source hybrid direct AC-AC power converter topology
title_sort three-level z-source hybrid direct ac-ac power converter topology
topic Z-source
Space vector modulation
Two-stage matrix converter
Voltage source inverter
url https://eprints.nottingham.ac.uk/14007/