Optimized Phase Disposition (PD) Modulation of a Modular Multilevel Converter

McGrath, Brendan; Teixeira, C. A.; Holmes, D.G.

doi:10.1109/tia.2017.2697953

Cited by 75 publications

(34 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The line to line output voltage having a lowest harmonic distortion is generated using PD-PWM and it also maintains equal switching frequency among the switching devices [117]. The optimal PD-PWM technique with interleaving angle greatly improves the harmonic spectrum of voltage [118] and the SM capacitor voltages are also balanced naturally [119]. However, one of the limitations of using PD-PWM is that it produces a large ripple in SM capacitor voltage which in turn causes an increase in the amplitude of the circulating current when compared with the phase shifted carrier PWM technique [120].…”

Section: Pwm Techniquesmentioning

confidence: 99%

Modular multilevel converters technology: a comprehensive study on its topologies, modelling, control and applications

Raju

Sreedevi

Mandi

et al. 2019

IET Power Electronics

View full text Add to dashboard Cite

A modular multilevel converter (MMC) is one of the perfect topologies for high power and medium-/high-voltage energy conversion systems. The MMC has attractive features such as modularity, voltage and current scalability, transformerless operation, fault blocking capability, reduced filter size, a reduced ripple of the output current, high efficiency, and low expense on redundancy. These features attracted industries over the past few years, notable research has been carried out on MMC topologies, their operation, and control. This study presents a review of MMC topologies and their mathematical models. Furthermore, their control schemes (classical as well as model predictive controls) and modulation techniques are discussed. Finally, MMC applications and their future challenges are highlighted.

show abstract

Section: Pwm Techniquesmentioning

confidence: 99%

Modular multilevel converters technology: a comprehensive study on its topologies, modelling, control and applications

Raju

Sreedevi

Mandi

et al. 2019

IET Power Electronics

View full text Add to dashboard Cite

show abstract

“…In this analysis, a Phase Shifted Carrier Pulse Width Modulation (PSCPWM) strategy is adopted. According to [27,28] Substituting (12) into (11) and solving (11) for Lg,t gives the value of the grid-side inductance, which is expressed in per unit value as…”

Section: A Lcl Parameters Estimationmentioning

confidence: 99%

Comparative Optimization Design of a Modular Multilevel Converter Tapping Cells and a 2L-VSC for Hybrid LV ac/dc Microgrids

Lachichi

Junyent-Ferré

Green

2019

IEEE Trans. on Ind. Applicat.

View full text Add to dashboard Cite

The paper presents the performance of the modular multilevel converter tapping cells associated with an ac filter in term of efficiency and power density in a hybrid LV ac/dc microgrid application and compares it to the performance of the conventional topology used in LV application, i.e., the Two-Level voltage source converter (2L VSC). A bi-objective optimization based on the Genetic Algorithm is hence developed, providing details on designing the components of the LCL filter, the MMC and the 2L VSC. The MMC reaches an efficiency of 99.4% when the main dcgrid is left floating. However, due to its modularity and scalability, offering multiport connections option, the MMC tapping cells has the disadvantage of low power density. Exploring the filtering capability of the equivalent arm inductance of the MMC seen from the ac grid side, optimization design results show that higher switching frequencies allow a significant volume reduction of the inductive components of the MMC/LCL filter while higher switching frequencies have little impact on the switching losses of the MMC. This has the benefit of reducing the overall footprint of the converter and encouraging the use of the MMC in LV application. Index Terms-Hybrid ac/dc microgrid, interlink converter, MMC, GA based optimization, tapping cells, two-level VSC.

show abstract

“…An appropriate control strategy is therefore crucial for an MMC because of the impact on output harmonics, filter size, switching frequency, power losses, etc. Similar to other power converter topologies, pulse-width modulation (PWM) with different configurations that include phase-and level-shifted carriers is the most common realization for MMCs [10]- [13]. The PWM control schemes offer low total harmonic distortion (THD), but these methods share some common drawbacks such as high switching frequency and complicated placement of a large number of SMs.…”

Section: Introductionmentioning

confidence: 99%

Nearest-Level Control Method With Improved Output Quality for Modular Multilevel Converters

Nguyen

Kwak

2020

IEEE Access

View full text Add to dashboard Cite

Nearest-level control (NLC) is a popular technique used in modular multilevel converters (MMCs) with a large number of submodules (SMs) owing to the NLC's flexibility and ease of implementation. However, in medium-voltage applications, MMCs contain a relatively low number of SMs, and the drawbacks of the NLC methods emerge, wherein the poor quality of output voltages and currents result in high total harmonic distortion, large ripples in SM capacitor voltages, and unsuppressed circulating currents. Several NLC methods have been proposed to handle these problems, but they do not satisfy all the control objectives simultaneously. This paper proposed a modified NLC capable of enhancing the output quality of MMCs with low number of SMs without deteriorating the control objectives. Unlike previously reported NLC methods, instead of directly calculating the numbers of SMs from the upper and lower arm voltage references, the difference and total number of SMs are obtained from the output voltage reference and circulating current control, respectively. Hence, the numbers of SMs in the upper and lower arms are acquired by simply solving a system of first-order two-variable equations. The simulated and experimental results for a single-phase MMC system were used to verify the appropriateness and effectiveness of the proposed modified NLC method.

show abstract

Optimized Phase Disposition (PD) Modulation of a Modular Multilevel Converter

Cited by 75 publications

References 27 publications

Modular multilevel converters technology: a comprehensive study on its topologies, modelling, control and applications

Modular multilevel converters technology: a comprehensive study on its topologies, modelling, control and applications

Comparative Optimization Design of a Modular Multilevel Converter Tapping Cells and a 2L-VSC for Hybrid LV ac/dc Microgrids

Nearest-Level Control Method With Improved Output Quality for Modular Multilevel Converters

Contact Info

Product

Resources

About