Impact of Harmonics and Unbalance on the Dynamics of Grid-Forming, Frequency-Droop-Controlled Inverters

Hart, Philip J.; Goldman, Joseph D.; Lasseter, R.H.; Jahns, T.M.

doi:10.1109/jestpe.2019.2949303

Cited by 31 publications

(28 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A novel control algorithm using double reduced-order generalised integrators for a four-leg shunt converter is presented in [214], while Sedhom et al [215] proposed another robust H ∞ based controller for unbalance mitigation in islanded MGs. Hoseinnia et al [216] proposed a double SRF (DSRF) control scheme without the need for load current sensors, while Hart et al [217] investigated the impact of harmonics and unbalance on the performance dynamics of gridforming converters modelled using the dynamic phasor approach. A novel control demand-side management algorithm based on voltage sensitivity is proposed in [218] as a possible solution for unbalance mitigation for an islanded MG having thermostatically controlled loads.…”

Section: Fig 4 Block Diagram Of a Typical Control Scheme For Addressmentioning

confidence: 99%

“…[216] proposed a double SRF (DSRF) control scheme without the need for load current sensors, while Hart et al . [217] investigated the impact of harmonics and unbalance on the performance dynamics of grid‐forming converters modelled using the dynamic phasor approach. A novel control demand‐side management algorithm based on voltage sensitivity is proposed in [218] as a possible solution for unbalance mitigation for an islanded MG having thermostatically controlled loads.…”

Section: Unbalance Mitigation In the Islanded Modementioning

confidence: 99%

See 1 more Smart Citation

Unbalance mitigation strategies in microgrids

Vijay

Doolla

Chandorkar

2020

IET Power Electronics

View full text Add to dashboard Cite

Unbalance or asymmetry in the distribution network is a well-known power quality issue. In the modern active distribution system, with the increasing penetration of renewables, this phenomenon becomes more pronounced. In the context of microgrids (MGs), several works have been proposed for the management and mitigation of the unbalance, for both the sharing of unbalanced load and maintaining the voltage quality in the islanded mode and for the control of distributed generators in the grid-connected mode during unbalanced conditions. This study comprehensively reviews, summarises, and classifies the various strategies of the unbalance mitigation techniques for the islanded and grid-connected modes of operation for threephase MGs and presents the possible challenges and avenues for future investigations on the topic.

show abstract

Section: Fig 4 Block Diagram Of a Typical Control Scheme For Addressmentioning

confidence: 99%

Section: Unbalance Mitigation In the Islanded Modementioning

confidence: 99%

Unbalance mitigation strategies in microgrids

Vijay

Doolla

Chandorkar

2020

IET Power Electronics

View full text Add to dashboard Cite

show abstract

“…in ( 44) - (46). If a specific harmonic content is of interest, one may include multiple dynamic phasors analogously to the study case in [47].…”

Section: A: Electrical Statesmentioning

confidence: 99%

On the Coupling of Power-Related and Inner Inverter Control Loops of Grid-Forming Converter Systems

Dokus

Mertens

2021

IEEE Access

View full text Add to dashboard Cite

In the last decade, different control concepts for the synchronisation of voltage-controlled power converters have been proposed in order to form converter-based power systems. The interoperability of these grid-forming power controls is often analysed based on reduced-order models covering only the slow controls or modes. In this article, the coupling of the outer, power-related and inner, inverter outputrelated control of multiple grid-forming power converter systems is analysed, based on a minimal working example. The elementary study cases each consist of a different grid-forming converter coupled with an external (and passive) grid. Here, the investigated stability problems are already manifested in the simplest possible setup. The analysis of these coupling effects is performed by modelling the system in impedancebased, state-space and phase portrait-based frameworks. In particular, small coupling impedances, like short transmission lines or small short circuit impedances, can be challenging for the controller stability of gridforming converters while the inner controls can even enhance this issue. The impact of this phenomenon and the participating subsystems are identified in this work. Thus, recommendations concerning modelling techniques and their legitimate assumptions are given. Laboratory experiments validate the performed analysis by indicating a close correlation between analytical models and experimental results. INDEX TERMSCoupling effects, grid-forming power converter, power-related control, stability analysis, voltage control.

show abstract

“…Examples and Applications: DPMs have been used to analyze power dynamics and faults in power systems [144], [145]. Other examples of DPMs used to successfully perform CDPS modeling and analysis are demonstrated in [20], [146], [148], [149], [151]- [153]. DPMs provide good system representation when the system dynamics can be approximated by a low-order approximation of the system that uses only a few coefficients [20].…”

Section: Dynamic Phasor Modelsmentioning

confidence: 99%

“…DPMs have been utilized to study whether grid-forming droop-controlled inverters are impacted by high harmonics or unbalance [153]. This work demonstrated that six-step switching harmonics and unbalance did not significantly impact a small systems' inverter dynamics.…”

Section: Dynamic Phasor Modelsmentioning

confidence: 99%

Review of Dynamic and Transient Modeling of Power Electronic Converters for Converter Dominated Power Systems

et al. 2021

View full text Add to dashboard Cite

In response to national and international carbon reduction goals, renewable energy resources like photovoltaics (PV) and wind, and energy storage technologies like fuel-cells are being extensively integrated in electric grids. All these energy resources require power electronic converters (PECs) to interconnect to the electric grid. These PECs have different response characteristics to dynamic stability issues compared to conventional synchronous generators. As a result, the demand for validated models to study and control these stability issues of PECs has increased drastically. This paper provides a review of the existing PEC model types and their applicable uses. The paper provides a description of the suitable model types based on the relevant dynamic stability issues. Challenges and benefits of using the appropriate PEC model type for studying each type of stability issue are also presented.

show abstract

Impact of Harmonics and Unbalance on the Dynamics of Grid-Forming, Frequency-Droop-Controlled Inverters

Cited by 31 publications

References 32 publications

Unbalance mitigation strategies in microgrids

Unbalance mitigation strategies in microgrids

On the Coupling of Power-Related and Inner Inverter Control Loops of Grid-Forming Converter Systems

Review of Dynamic and Transient Modeling of Power Electronic Converters for Converter Dominated Power Systems

Contact Info

Product

Resources

About