Performance of solid state transformers under imbalanced loads in distribution systems

Yang, Tao; Meere, Ronan; O’Loughlin, Cathal; O’Donnell, Terence

doi:10.1109/apec.2016.7468235

Cited by 7 publications

(2 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…2. By application of the three-dimensional space vector modulation (3-D SVPWM), each phase can be independently regulated through the fourth leg, thus control of the three phase voltages are decoupled [29] [30].…”

Section: Sst Configurationmentioning

confidence: 99%

Neutral Current Minimization Control for Solid State Transformers Under Unbalanced Loads in Distribution Systems

Chen

Yang²,

O’Loughlin

et al. 2019

IEEE Trans. Ind. Electron.

Self Cite

View full text Add to dashboard Cite

This paper analyses the neutral current reduction performance of a three phase four leg solid state transformer (SST) under different degrees of unbalanced load. Several kinds of control strategies are presented, the neutral current elimination controls which rely on phase shifting, voltage amplitude and phase shifting & voltage amplitude combination control. A neutral current minimization control which ensures the SST output voltages complies with the EN 50160 output voltage unbalance standard is also developed. These control approaches simply build on the balanced voltage control providing voltage references which slightly unbalanced the voltage amplitude and phase angle or both. The effectiveness of the proposed strategies is validated through tests on a downscaled prototype. Simulation results for the neutral current minimization control of the SST applied to a real urban distribution network with distributed loads are presented. The results of this analysis show that overall the neutral current minimization results in an energy saving from both reduced losses in the distribution cables and reduced power consumption in the load.

show abstract

Section: Sst Configurationmentioning

confidence: 99%

Neutral Current Minimization Control for Solid State Transformers Under Unbalanced Loads in Distribution Systems

Chen

Yang²,

O’Loughlin

et al. 2019

IEEE Trans. Ind. Electron.

Self Cite

View full text Add to dashboard Cite

show abstract

“…The PET is a relatively new device that utilizes power electronic converters to transform electrical power between not only different AC voltage levels but also different frequencies and forms (e.g., AC-DC and DC-AC conversion). Among the several different proposed topologies and implementations of PET, possibly the most researched approach is the three-stage PET due to its high level of controllability and flexibility (Wang et al, 2012;Yang et al, 2016;Ferreira Costa et al, 2017). The PET facilitates new active control functionalities for AC distribution networks in terms of, for example, power flow control, voltage regulation, and limitation of neutral and fault currents, which cannot be implemented by traditional iron-copper Low-Frequency Transformers (LFT) (She et al, 2013;Chen et al, 2019).…”

Section: Introductionmentioning

confidence: 99%

Hybrid Power Electronic Transformer Model for System-Level Benefits Quantification in Energy Distribution Systems

et al. 2021

View full text Add to dashboard Cite

The Hybrid Power Electronic Transformer (HPET) has been proposed as an efficient and economical solution to some of the problems caused by Distributed Energy Resources and new types of loads in existing AC distribution systems. Despite this, the HPET has some limitations on the control it can exert due to its fractionally-rated Power Electronic Converter. Various HPET topologies with different capabilities have been proposed, being necessary to investigate the system benefits that they might provide in possible future scenarios. Adequate HPET models are needed in order to conduct such system-level studies, which are still not covered in the current literature. Consequently, this article presents a methodology to develop power flow models of HPET that facilitate the quantification of controllability requirements for voltage, active power and reactive power. A particular HPET topology composed of a three-phase three-winding Low-Frequency Transformer coupled with a Back-to-Back converter is modeled as an example. The losses in the Back-to-Back converter are represented through efficiency curves that are assigned individually to the two modules. The model performance is illustrated through various power flow simulations that independently quantify voltage regulation and reactive power compensation capabilities for different power ratings of the Power Electronic Converter. In addition, a set of daily simulations were conducted with the HPET supplying a real distribution network modeled in OpenDSS. The results show the HPET losses to be around 1.3 times higher than the conventional transformer losses over the course of the day. The proposed methodology offers enough flexibility to investigate different HPET features, such as power ratings of the Power Electronic Converter, losses, and various strategies for the controlled variables. The contribution of this work is to provide a useful tool that can not only assess and quantify some of the system-level benefits that the HPET can provide, but also allow a network-tailored design of HPETs. The presented model along with the simulation platform were made publicly available.

show abstract

Small signal averaged transfer function model and controller design of modular solid state transformers

Jeyapradha¹,

Rajini

2019

ISA Transactions

View full text Add to dashboard Cite

Performance of solid state transformers under imbalanced loads in distribution systems

Cited by 7 publications

References 19 publications

Neutral Current Minimization Control for Solid State Transformers Under Unbalanced Loads in Distribution Systems

Neutral Current Minimization Control for Solid State Transformers Under Unbalanced Loads in Distribution Systems

Hybrid Power Electronic Transformer Model for System-Level Benefits Quantification in Energy Distribution Systems

Small signal averaged transfer function model and controller design of modular solid state transformers

Contact Info

Product

Resources

About