Interleaved Operation of Two Neutral-Point-Clamped Inverters With Reduced Circulating Current
- 31 January 2018
- journal article
- research article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Transactions on Power Electronics
- Vol. 33 (12), 10122-10134
- https://doi.org/10.1109/tpel.2018.2800402
Abstract
Parallel inverters are commonly adopted in high-power applications, for instance wind energy systems, smart transformers, and power conditioners. Meanwhile, interleaved pulse width modulation is usually considered as an optimal approach to reduce the current ripple and harmonics of the parallel inverters. However, in the case of a common dc link, the problem of circulating current emerges and leads to performance degradation. This paper aims at investigating the influence of different modulation techniques on the circulating current of two neutral-point-clamped (NPC) inverters under interleaved operation. Two modulation techniques, phase disposition (PD) and alternative phase opposite disposition (APOD), have been studied and compared in terms of current ripple, spectrum quality, and circulating current. Though the PD modulation was regarded as the optimum solution in most of the single-NPC cases, it offers worse performance in the two parallel NPC applications due to higher circulating current. Simulation and experimental validations are provided and show that the APOD leads to much lower circulating current and similar current ripple as well as spectrum quality compared to the PD.Keywords
Funding Information
- H2020 European Research Council
- European Unions Seventh Framework (FP/2007-2013)
- ERC (616344—HEART)
- Federal Ministry for Economic Affairs and Energy (0325797A)
This publication has 15 references indexed in Scilit:
- A Novel STATCOM Based on Diode-Clamped Modular Multilevel ConvertersIEEE Transactions on Power Electronics, 2016
- The Smart Transformer: Impact on the Electric Grid and Technology ChallengesIEEE Industrial Electronics Magazine, 2016
- A Three-Level Space Vector Modulation Scheme for Paralleled Converters to Reduce Circulating Current and Common-Mode VoltageIEEE Transactions on Power Electronics, 2016
- Modified Discontinuous PWM for Size Reduction of the Circulating Current Filter in Parallel Interleaved ConvertersIEEE Transactions on Power Electronics, 2014
- PD Modulation Scheme for Three-Phase Parallel Multilevel InvertersIEEE Transactions on Industrial Electronics, 2011
- Overview of Multi-MW Wind Turbines and Wind ParksIEEE Transactions on Industrial Electronics, 2011
- Optimized space vector switching sequences for multilevel invertersIEEE Transactions on Power Electronics, 2003
- Sine-triangle versus space-vector modulation for three-level PWM voltage-source invertersIEEE Transactions on Industry Applications, 2002
- Application of parallel connected NPC-PWM inverters with multilevel modulation for AC motor driveIEEE Transactions on Power Electronics, 2000
- Interleaved PWM with discontinuous space-vector modulationIEEE Transactions on Power Electronics, 1999