Modern energy resources, such as photovoltaics, batteries, wind, and electric vehicles are interfaced to the grid through power electronics. These interfaces are fundamentally distinct from conventional synchronous generators in that they do not contain moving parts and their dynamics are shaped with digital controls. As generation shifts from large rotating machines to collections of electronic interfaces dispersed across the grid, system dynamics will accelerate under reduced inertia and system structures will become increasingly decentralized. Our group is reimagining the way grids are built and stands at the forefront of grid-forming inverter technologies that enable scalable and resilient power systems. UT Austin is also a co-lead of the UNIFI Consortium.

low inertia

Selected Publications

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53 entries « 1 of 2 »

2025

53.

Chatterjee, Debjyoti; Yang, Bowen; Johnson, Brian; Seo, Gab-Su

Interaction Energy-Based Transient Stability Framework for Multi-Grid-Forming Inverter Systems Proceedings Article

In: Energy Conversion Congress and Exposition, 2025.

Links | BibTeX | Tags: inverters, modeling, systems

52.

Chatterjee, Debjyoti; Baeckeland, Nathan; Johnson, Brian; Seo, Gab-Su; Dhople, Sairaj

Demystifying Grid-forming Inverter Large-signal Stability Assessment with Equivalent-circuit Models Proceedings Article

In: Workshop on Control and Modeling of Power Electronics, 2025.

Links | BibTeX | Tags: inverter control, modeling, systems

51.

Chatterjee, Debjyoti; Johnson, Brian; Seo, Gab-Su

Is equal area criterion applicable for transient stability assessment of grid-forming inverters? Proceedings Article

In: Power and Energy Society General Meeting, 2025.

Links | BibTeX | Tags: inverter control, modeling

50.

Chatterjee, Debjyoti; Seo, Gab-Su; Johnson, Brian

Stability analysis of multi-inverter systems with heterogeneous grid-forming dynamics Proceedings Article

In: Power and Energy Society General Meeting, 2025.

Links | BibTeX | Tags: inverter control, inverters, modeling, systems

49.

Chatterjee, Debjyoti; Triemstra, Jakob; Macías, Cuauhtémoc; Cai, Weiqian; Tatkare, Kamakshi; Mallik, Rahul; Johnson, Brian

UNIFI's Grid-Forming (GFM) Inverter Reference Design: A Tutorial on Modeling, Control, and Experimental Implementation of GFM Inverters Technical Manual

National Renewable Energy Lab.(NREL), Golden, CO (United States) 2025.

Links | BibTeX | Tags: converter design, inverter control, modeling, power electronics control

48.

Chandran, Pranav; Mallik, Rahul; Kim, InYong; Brekken, Ted; Johnson, Brian

Design and analysis of an integral MPPT control law for wave energy conversion systems Proceedings Article

In: Workshop on Control and Modeling of Power Electronics, 2025.

Links | BibTeX | Tags: electromechanics, inverter control, modeling, systems

47.

Liu, Shaohui; Cai, Weiqian; Zhu, Hao; Johnson, Brian

A unified approach for learning the dynamics of power system generators and inverter-based resources Proceedings Article

In: Hawaii International Conference on System Sciences, 2025.

Links | BibTeX | Tags: modeling, neural network, systems

2024

46.

Baeckeland, Nathan; Ankner, Thomas; Dhople, Sairaj; Johnson, Brian; Seo, Gab-Su

Equivalent-circuit models of grid-forming IBRs for electromagnetic-transient simulations Proceedings Article

In: Power and Energy Society General Meeting, 2024.

Links | BibTeX | Tags: inverters, modeling

2023

45.

Cai, Weiqian; Lu, Minghui; Johnson, Brian

Inverter-based emulation of single-phase air conditioner loads Proceedings Article

In: Energy Conversion Congress and Exposition, 2023.

Links | BibTeX | Tags: electromechanics, inverter control, inverters, modeling

44.

Lu, Minghui; Cai, Weiqian; Dhople, Sairaj; Johnson, Brian

Large-signal stability of phase-balanced equilibria in single-phase grid-forming inverter systems Journal Article

In: IEEE Transactions on Power Electronics, 2023.

Links | BibTeX | Tags: inverters, modeling, systems

43.

Pal, Diptak; Panigrahi, Bijaya Ketan; Johnson, Brian; Venkatramanan, D; Dhople, Sairaj

Large-signal stability analysis of three-phase grid-following inverters Journal Article

In: IEEE Transactions on Energy Conversion, 2023.

Links | BibTeX | Tags: inverters, modeling

42.

Ramasubramanian, Deepak; Farantatos, Evangelos; Ajala, Olaoluwapo; Dhople, Sairaj; Johnson, Brian

A universal grid-forming inverter model and simulation-based characterization across timescales Proceedings Article

In: Hawaii International Conference on System Sciences, 2023.

Links | BibTeX | Tags: inverters, modeling, systems

2022

41.

Johnson, Brian; Roberts, T. G.; Ajala, Olaolu; Dominguez-Garcia, Alejandro; Dhople, Sairaj; Ramasubramanian, Deepak; Tuohy, Aidan; Divan, Deepak; Kroposki, Benjamin

A generic primary-control model for grid-forming inverters: Towards interoperable operation and control Proceedings Article

In: Hawaii International Conference on System Sciences, pp. 3398-3407, 2022.

Links | BibTeX | Tags: inverter control, inverters, modeling

2021

40.

Ajala, Olaoluwapo; Lu, Minghui; Dhople, Sairaj; Johnson, Brian; Domínguez-García, Alejandro

Model reduction for inverters with current limiting and dispatchable virtual oscillator control Journal Article

In: IEEE Transactions on Energy Conversion, pp. 1-1, 2021.

Links | BibTeX | Tags: inverters, modeling

39.

Jafarpour, Saber; Purba, Victor; Johnson, Brian; Dhople, Sairaj; Bullo, Francesco

Singular perturbation and small-signal stability for inverter networks Journal Article

In: IEEE Transactions on Control of Network Systems, pp. 1-1, 2021.

Links | BibTeX | Tags: modeling, systems

38.

Lu, Minghui; Purba, Victor; Dhople, Sairaj; Johnson, Brian

Unified equivalent-circuit models for voltage-source inverters that capture averaged dynamics and power-flow solutions in distribution networks Proceedings Article

In: Hawaii International Conference on System Sciences, pp. 1–10, 2021.

Links | BibTeX | Tags: inverters, modeling

37.

Venkatramanan, D; Vamanan, Nimesh; Johnson, Brian; Dhople, Sairaj

Quantitative analysis of third-harmonic neutral-point current, its impacts, and mitigation in three-level NPC inverters Proceedings Article

In: Energy Conversion Congress and Exposition, pp. 3563–3570, IEEE 2021.

Links | BibTeX | Tags: inverters, modeling

36.

Venkatramanan, D; Johnson, Brian; Dhople, Sairaj

Averaged dynamic model of three-level NPC grid-following inverter for examining neutral-point instability Proceedings Article

In: Workshop on Control and Modeling of Power Electronics, pp. 1–7, IEEE 2021.

Links | BibTeX | Tags: inverters, modeling

35.

Billmeyer, Ryan; Lu, Minghui; Johnson, Brian; Dhople, Sairaj

Modeling and simulation of power-electronic inverters in analog electronic circuit simulators Proceedings Article

In: International Symposium on Circuits and Systems, pp. 1–5, IEEE 2021.

Links | BibTeX | Tags: modeling, systems

2020

34.

Chandran, Pranav; Johnson, Brian; Rose, Blake

Equivalent circuit models for closed-loop multiphysics drive systems Proceedings Article

In: Workshop on Control and Modeling for Power Electronics, pp. 1–7, IEEE 2020.

Links | BibTeX | Tags: electromechanics, modeling

33.

Lu, Minghui; Purba, Victor; Dhople, Sairaj; Johnson, Brian

Comparison of droop control and virtual oscillator control realized by Andronov-Hopf dynamics Proceedings Article

In: Conference of the IEEE Industrial Electronics Society, pp. 4051–4056, IEEE 2020.

Links | BibTeX | Tags: inverters, modeling

32.

Mallik, Rahul; Pace, Andrew; Burden, Samuel; Johnson, Brian

Accurate small-signal discrete-time model of dual active bridge using saltation matrices Proceedings Article

In: Energy Conversion Congress and Exposition, pp. 6312–6317, IEEE 2020.

Links | BibTeX | Tags: dc-dc converters, modeling

2019

31.

Purba, Victor; Johnson, Brian; Jafarpour, Saber; Bullo, Francesco; Dhople, Sairaj

Dynamic aggregation of grid-tied three-phase inverters Journal Article

In: IEEE Transactions on Power Systems, vol. 35, no. 2, pp. 1520–1530, 2019.

Links | BibTeX | Tags: modeling, systems

30.

Pico, Hugo Villegas; Johnson, Brian

Transient stability assessment of multi-machine multi-converter power systems Journal Article

In: IEEE Transactions on Power Systems, vol. 34, no. 5, pp. 3504–3514, 2019.

Links | BibTeX | Tags: modeling, systems

29.

Johnson, Brian; Lu, Minghui; Purba, Victor; Dhople, Sairaj

Circuit-equivalent models for current-controlled inverters Proceedings Article

In: Workshop on Control and Modeling for Power Electronics, pp. 1–5, IEEE 2019.

Links | BibTeX | Tags: dc-dc converters, modeling

28.

Mallik, Rahul; Majmunović, Branko; Mukherjee, Satyaki; Dutta, Soham; Seo, Gab-Su; Maksimović, Dragan; Johnson, Brian

Equivalent circuit models of voltage-controlled dual active bridge converters Proceedings Article

In: Workshop on Control and Modeling for Power Electronics, pp. 1–4, IEEE 2019.

Links | BibTeX | Tags: dc-dc converters, modeling

27.

Purba, Victor; Johnson, Brian; Dhople, Sairaj

Reduced-order aggregate model for parallel-connected grid-tied three-phase photovoltaic inverters Proceedings Article

In: Photovoltaic Specialists Conference, pp. 0724–0729, IEEE 2019.

Links | BibTeX | Tags: modeling, systems

26.

Pierre, Brian; Pico, Hugo Villegas; Elliott, Ryan; Flicker, Jack; Lin, Yashen; Johnson, Brian; Eto, Joseph; Lasseter, Robert; Ellis, Abraham

Bulk power system dynamics with varying levels of synchronous generators and grid-forming power inverters Proceedings Article

In: Photovoltaic Specialists Conference, pp. 0880–0886, IEEE 2019.

Links | BibTeX | Tags: modeling, systems

2018

25.

Lu, Minghui; Yang, Yongheng; Johnson, Brian; Blaabjerg, Frede

An interaction-admittance model for multi-inverter grid-connected systems Journal Article

In: IEEE Transactions on Power Electronics, vol. 34, no. 8, pp. 7542–7557, 2018.

Links | BibTeX | Tags: modeling, systems

24.

Purba, Victor; Johnson, Brian; Rodriguez, Miguel; Jafarpour, Saber; Bullo, Francesco; Dhople, Sairaj

Reduced-order aggregate model for parallel-connected single-phase inverters Journal Article

In: IEEE Transactions on Energy Conversion, vol. 34, no. 2, pp. 824–837, 2018.

Links | BibTeX | Tags: inverters, modeling

23.

Cale, James; Johnson, Brian; Dall’Anese, Emiliano; Young, Peter; Duggan, Gerald; Bedge, Poorva; Zimmerle, Daniel; Holton, Leah

Mitigating communication delays in remotely connected hardware-in-the-loop experiments Journal Article

In: IEEE transactions on industrial electronics, vol. 65, no. 12, pp. 9739–9748, 2018.

Links | BibTeX | Tags: modeling

22.

Sinha, Mohit; Dörfler, Florian; Johnson, Brian; Dhople, Sairaj

Synchronization of Linear-type oscillators in heterogenous electrical networks Proceedings Article

In: Indian Control Conference, pp. 240–245, IEEE 2018.

Links | BibTeX | Tags: modeling

21.

Sinha, Mohit; Dörfler, Florian; Johnson, Brian; Dhople, Sairaj

Stabilizing phase-balanced or phase-synchronized trajectories of Van der Pol oscillators in uniform electrical networks Proceedings Article

In: Allerton Conference on Communication, Control, and Computing, pp. 335–340, IEEE 2018.

Links | BibTeX | Tags: inverters, modeling

20.

Khan, Mohammed; Lin, Yashen; Johnson, Brian; Purba, Victor; Sinha, Mohit; Dhople, Sairaj

A reduced-order aggregated model for parallel inverter systems with virtual oscillator control Proceedings Article

In: Workshop on Control and Modeling for Power Electronics, pp. 1–6, IEEE 2018.

Links | BibTeX | Tags: inverters, modeling

19.

Achanta, Prasanta; Sinha, Mohit; Johnson, Brian; Dhople, Sairaj; Maksimović, Dragan

Self-synchronizing series-connected inverters Proceedings Article

In: Workshop on Control and Modeling for Power Electronics, pp. 1–6, IEEE 2018.

Links | BibTeX | Tags: inverters, modeling

18.

Khan, Mohammed; Lin, Yashen; Johnson, Brian; Sinha, Mohit; Dhople, Sairaj

Stability assessment of a system comprising a single machine and a virtual oscillator controlled inverter with scalable ratings Proceedings Article

In: Conference of the IEEE Industrial Electronics Society, pp. 4057–4062, IEEE 2018.

Links | BibTeX | Tags: modeling, systems

2017

17.

Sinha, Mohit; Dörfler, Florian; Johnson, Brian; Dhople, Sairaj

Phase balancing in globally connected networks of linear oscillators Proceedings Article

In: Conference on Decision and Control, pp. 595–600, IEEE 2017.

Links | BibTeX | Tags: modeling, systems

16.

Johnson, Brian; Rodriguez, Miguel; Sinha, Mohit; Dhople, Sairaj

Comparison of virtual oscillator and droop control Proceedings Article

In: Workshop on Control and Modeling for Power Electronics, pp. 1–6, IEEE 2017.

Links | BibTeX | Tags: inverters, modeling

15.

Purba, Victor; Dhople, Sairaj; Jafarpour, Saber; Bullo, Francesco; Johnson, Brian

Reduced-order structure-preserving model for parallel-connected three-phase grid-tied inverters Proceedings Article

In: Workshop on Control and Modeling for Power Electronics, pp. 1–7, IEEE 2017.

Links | BibTeX | Tags: modeling, systems

14.

Lin, Yashen; Johnson, Brian; Gevorgian, Vahan; Purba, Victor; Dhople, Sairaj

Stability assessment of a system comprising a single machine and inverter with scalable ratings Proceedings Article

In: North American Power Symposium, pp. 1–6, IEEE 2017.

Links | BibTeX | Tags: modeling, systems

2016

13.

Johnson, Brian; Lundstrom, Blake; Salapaka, Srinivasa; Salapaka, Murti

Optimal structures for voltage controllers in inverters Proceedings Article

In: International Symposium on Mathematical Theory of Networks and Systems, 2016.

Links | BibTeX | Tags: modeling

12.

Johnson, Brian; Krein, Philip

An analytical time--domain expression for the net ripple produced by parallel interleaved converters Journal Article

In: IEEE Transactions on Circuits and Systems II: Express Briefs, vol. 64, no. 3, pp. 289–293, 2016.

Links | BibTeX | Tags: modeling

11.

Sinha, Mohit; Dörfler, Florian; Johnson, Brian; Dhople, Sairaj

Synchronization of linear-type oscillators in uniform electrical networks Proceedings Article

In: American control conference, pp. 4311–4316, IEEE 2016.

Links | BibTeX | Tags: modeling, systems

2015

10.

Sinha, Mohit; Dörfler, Florian; Johnson, Brian; Dhople, Sairaj

Uncovering droop control laws embedded within the nonlinear dynamics of van der pol oscillators Journal Article

In: IEEE Transactions on Control of Network Systems, vol. 4, no. 2, pp. 347–358, 2015.

Links | BibTeX | Tags: inverters, modeling

9.

Sinha, Mohit; Dhople, Sairaj; Johnson, Brian; Ainsworth, Nathan; Dörfler, Florian

Nonlinear supersets to droop control Proceedings Article

In: Workshop on Control and Modeling for Power Electronics, pp. 1–6, IEEE 2015.

Links | BibTeX | Tags: inverters, modeling

8.

Sinha, Mohit; Dörfler, Florian; Johnson, Brian; Dhople, Sairaj

Virtual oscillator control subsumes droop control Proceedings Article

In: American Control Conference, pp. 2353–2358, IEEE 2015.

Links | BibTeX | Tags: inverters, modeling

2014

7.

Dhople, Sairaj; Johnson, Brian; Dörfler, Florian; Hamadeh, Abdullah

Synchronization of nonlinear circuits in dynamic electrical networks with general topologies Journal Article

In: IEEE Transactions on Circuits and Systems I: Regular Papers, vol. 61, no. 9, pp. 2677–2690, 2014.

Links | BibTeX | Tags: modeling, systems

6.

Johnson, Brian; Dhople, Sairaj; Hamadeh, Abdullah; Krein, Philip

Synchronization of nonlinear oscillators in an LTI electrical power network Journal Article

In: IEEE Transactions on Circuits and Systems I: Regular Papers, vol. 61, no. 3, pp. 834–844, 2014.

Links | BibTeX | Tags: modeling, systems

5.

Salapaka, Srinivasa; Johnson, Brian; Lundstrom, Blake; Kim, Sangsun; Collyer, Scott; Salapaka, Murti

Viability and analysis of implementing only voltage-power droop for parallel inverter systems Proceedings Article

In: Conference on Decision and Control, pp. 3246–3251, IEEE 2014.

Links | BibTeX | Tags: inverters, modeling

4.

Dörfler, Florian; Dhople, Sairaj; Johnson, Brian; Hamadeh, Abdullah

Synchronization of nonlinear circuits in dynamic electrical networks Proceedings Article

In: European Control Conference, pp. 552–557, IEEE 2014.

Links | BibTeX | Tags: inverters, modeling

53 entries « 1 of 2 »