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Title: Modular Cascaded H-Bridge Multilevel PV Inverter with Distributed MPPT for Grid-Connected Applications

Abstract

This paper presents a modular cascaded H-bridge multilevel photovoltaic (PV) inverter for single- or three-phase grid-connected applications. The modular cascaded multilevel topology helps to improve the efficiency and flexibility of PV systems. To realize better utilization of PV modules and maximize the solar energy extraction, a distributed maximum power point tracking (MPPT) control scheme is applied to both single-phase and three-phase multilevel inverters, which allows the independent control of each dc-link voltage. For three-phase grid-connected applications, PV mismatches may introduce unbalanced supplied power, leading to unbalanced grid current. To solve this issue, a control scheme with modulation compensation is also proposed. An experimental three-phase 7-level cascaded H-bridge inverter has been built utilizing 9 H-bridge modules (3 modules per phase). Each H-bridge module is connected to a 185 W solar panel. Simulation and experimental results are presented to verify the feasibility of the proposed approach.

Authors:
 [1];  [1];  [2];  [1];  [1];  [3]
  1. Univ. of Tennessee, Knoxville, TN (United States)
  2. Southeast Univ., Nanjing (China)
  3. Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1265683
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
IEEE Transactions on Industry Applications
Additional Journal Information:
Journal Volume: 51; Journal Issue: 2; Journal ID: ISSN 0093-9994
Publisher:
IEEE
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; Photovoltaic; Distributed MPPT; Cascaded multilevel inverter; Modular; Modulated compensation

Citation Formats

Xiao, Bailu, Hang, Lijun, Mei, Jun, Riley, Cameron, Tolbert, Leon M., and Ozpineci, Burak. Modular Cascaded H-Bridge Multilevel PV Inverter with Distributed MPPT for Grid-Connected Applications. United States: N. p., 2014. Web. doi:10.1109/TIA.2014.2354396.
Xiao, Bailu, Hang, Lijun, Mei, Jun, Riley, Cameron, Tolbert, Leon M., & Ozpineci, Burak. Modular Cascaded H-Bridge Multilevel PV Inverter with Distributed MPPT for Grid-Connected Applications. United States. doi:10.1109/TIA.2014.2354396.
Xiao, Bailu, Hang, Lijun, Mei, Jun, Riley, Cameron, Tolbert, Leon M., and Ozpineci, Burak. Thu . "Modular Cascaded H-Bridge Multilevel PV Inverter with Distributed MPPT for Grid-Connected Applications". United States. doi:10.1109/TIA.2014.2354396. https://www.osti.gov/servlets/purl/1265683.
@article{osti_1265683,
title = {Modular Cascaded H-Bridge Multilevel PV Inverter with Distributed MPPT for Grid-Connected Applications},
author = {Xiao, Bailu and Hang, Lijun and Mei, Jun and Riley, Cameron and Tolbert, Leon M. and Ozpineci, Burak},
abstractNote = {This paper presents a modular cascaded H-bridge multilevel photovoltaic (PV) inverter for single- or three-phase grid-connected applications. The modular cascaded multilevel topology helps to improve the efficiency and flexibility of PV systems. To realize better utilization of PV modules and maximize the solar energy extraction, a distributed maximum power point tracking (MPPT) control scheme is applied to both single-phase and three-phase multilevel inverters, which allows the independent control of each dc-link voltage. For three-phase grid-connected applications, PV mismatches may introduce unbalanced supplied power, leading to unbalanced grid current. To solve this issue, a control scheme with modulation compensation is also proposed. An experimental three-phase 7-level cascaded H-bridge inverter has been built utilizing 9 H-bridge modules (3 modules per phase). Each H-bridge module is connected to a 185 W solar panel. Simulation and experimental results are presented to verify the feasibility of the proposed approach.},
doi = {10.1109/TIA.2014.2354396},
journal = {IEEE Transactions on Industry Applications},
number = 2,
volume = 51,
place = {United States},
year = {Thu Sep 04 00:00:00 EDT 2014},
month = {Thu Sep 04 00:00:00 EDT 2014}
}

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Free Publicly Available Full Text
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Cited by: 89works
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  • A three-phase modular cascaded H-bridge multilevel inverter for a grid-connected photovoltaic (PV) system is presented in this paper. To maximize the solar energy extraction of each PV string, an individual maximum power point tracking (MPPT) control scheme is applied, which allows the independent control of each dc-link voltage. PV mismatches may introduce unbalanced power supplied to the three-phase system. To solve this issue, a control scheme with modulation compensation is proposed. The three-phase modular cascaded multilevel inverter prototype has been built. Each H-bridge is connected to a 185 W solar panel. Simulation and experimental results are presented to validate themore » proposed ideas.« less
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