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 dutyratios. Here, interleaving refers to the condition when a collection of periodic waveforms with identical periods are each uniformly phaseshifted across one period. The main result is a timedomain expression which provides an exact representation of the summed and interleaved triangular waveforms, where the peak amplitude and parameters of the timeperiodic component are all specified in closedform. Analysis is general and can be used to study various applications in multiconverter 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 timevarying 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/JA5D0066257
Journal ID: ISSN 15497747
 DOE Contract Number:
 AC3608GO28308
 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; dcdc 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 dutyratios. Here, interleaving refers to the condition when a collection of periodic waveforms with identical periods are each uniformly phaseshifted across one period. The main result is a timedomain expression which provides an exact representation of the summed and interleaved triangular waveforms, where the peak amplitude and parameters of the timeperiodic component are all specified in closedform. Analysis is general and can be used to study various applications in multiconverter 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 timevarying 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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