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Title: An Analytical Time–Domain Expression for the Net Ripple Produced by Parallel Interleaved Converters

Abstract

We apply modular arithmetic and Fourier series to analyze the superposition of N interleaved triangular waveforms with identical amplitudes and duty-ratios. Here, interleaving refers to the condition when a collection of periodic waveforms with identical periods are each uniformly phase-shifted across one period. The main result is a time-domain expression which provides an exact representation of the summed and interleaved triangular waveforms, where the peak amplitude and parameters of the time-periodic component are all specified in closed-form. Analysis is general and can be used to study various applications in multi-converter systems. This model is unique not only in that it reveals a simple and intuitive expression for the net ripple, but its derivation via modular arithmetic and Fourier series is distinct from prior approaches. The analytical framework is experimentally validated with a system of three parallel converters under time-varying operating conditions.

Authors:
;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
NREL Laboratory Directed Research and Development (LDRD)
OSTI Identifier:
1346338
Report Number(s):
NREL/JA-5D00-66257
Journal ID: ISSN 1549-7747
DOE Contract Number:
AC36-08GO28308
Resource Type:
Journal Article
Resource Relation:
Journal Name: IEEE Transactions on Circuits and Systems. II, Express Briefs; Journal Volume: 64; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
24 POWER TRANSMISSION AND DISTRIBUTION; interleaving; parallel converters; dc-dc converters; inverters; Fourier analysis; modular arithmetic

Citation Formats

Johnson, Brian B., and Krein, Philip T.. An Analytical Time–Domain Expression for the Net Ripple Produced by Parallel Interleaved Converters. United States: N. p., 2017. Web. doi:10.1109/TCSII.2016.2557620.
Johnson, Brian B., & Krein, Philip T.. An Analytical Time–Domain Expression for the Net Ripple Produced by Parallel Interleaved Converters. United States. doi:10.1109/TCSII.2016.2557620.
Johnson, Brian B., and Krein, Philip T.. Wed . "An Analytical Time–Domain Expression for the Net Ripple Produced by Parallel Interleaved Converters". United States. doi:10.1109/TCSII.2016.2557620.
@article{osti_1346338,
title = {An Analytical Time–Domain Expression for the Net Ripple Produced by Parallel Interleaved Converters},
author = {Johnson, Brian B. and Krein, Philip T.},
abstractNote = {We apply modular arithmetic and Fourier series to analyze the superposition of N interleaved triangular waveforms with identical amplitudes and duty-ratios. Here, interleaving refers to the condition when a collection of periodic waveforms with identical periods are each uniformly phase-shifted across one period. The main result is a time-domain expression which provides an exact representation of the summed and interleaved triangular waveforms, where the peak amplitude and parameters of the time-periodic component are all specified in closed-form. Analysis is general and can be used to study various applications in multi-converter systems. This model is unique not only in that it reveals a simple and intuitive expression for the net ripple, but its derivation via modular arithmetic and Fourier series is distinct from prior approaches. The analytical framework is experimentally validated with a system of three parallel converters under time-varying operating conditions.},
doi = {10.1109/TCSII.2016.2557620},
journal = {IEEE Transactions on Circuits and Systems. II, Express Briefs},
number = 3,
volume = 64,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2017},
month = {Wed Mar 01 00:00:00 EST 2017}
}
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