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Non-unit protection method for MMC-HVDC grids based on selective drop rate of voltage traveling waves

Dehghan Marvasti, F. (author), Mirzaei, Ahmad (author), Savaghebi, Mehdi (author), Lekić, A. (author), Popov, M. (author)

Fast, sensitive, and selective protection principles are one of the major challenges in the feasibility of modular multi-terminal (MMC) high voltage direct current (HVDC) grids. Rate of change of voltage (ROCOV) and transient-based solutions are the traditional and widely accepted protection principles. Despite the speed and practicality of...

journal article 2024

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Enhanced Real-Time Multi-Terminal HVDC Power System Benchmark Models with Performance Evaluation Strategies

Shetgaonkar, A.D. (author), Karmokar, T.R. (author), Popov, M. (author), Lekić, A. (author)

Real-time simulations have become a crucial tool for life cycle studies of VSC-based HVDC systems. This paper introduces real-time Multi-Terminal HVDC (MTDC) power [1] system network models with real-time wind pro le feedback. It addresses the shortcomings of existing benchmark network models and lls the modeling gaps. ® RSCAD/RTDS...

journal article 2024

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Single-ended DC Fault Location Method For MMC-Based HVDC Power System Using Adaptive Multi-step Levenberg-Marquardt Algorithm

Liu, L. (author), Xie, F. (author), Popov, M. (author), Hao, Zhiguo (author), Lekić, A. (author)

This article presents an accurate DC fault location method that applies parameter fitting. This technique first discusses the traveling wave (TW) propagation process in the decoupled line-mode network. We obtain the exact fault distance equation based on the analytical expressions for the wavefront of backward line-mode voltage TW. The adaptive...

conference paper 2023

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Non-Unit DC Line Protection Method for Multi-Terminal MMC-HVDC System Based on Normalized Backward Traveling Waves

Xie, F. (author), Liu, L. (author), Hao, Zhiguo (author), Lekić, A. (author), Popov, M. (author)

Existing line protection methods for multi-terminal direct current (MTDC) systems are constrained by the placement and values of boundary elements. To overcome this limitation, this paper proposes a non-unit DC line protection method based on the normalized backward traveling waves (BTWs) of the 1-mode voltage. Firstly, this article studies...

conference paper 2023

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Development of Reliable Power Electronic Systems using Real Time Digital Twin Based Power Hardware-in-the-Loop Testbed

Shekhar, A. (author), Rituraj, G. (author), van der Sande, Robin (author), Ahmadi, M. (author), Deshmukh, R.S. (author), Bauer, P. (author), Nougain, V. (author), Lekić, A. (author), Palensky, P. (author)

Reliable Power Electronic Systems (PES) are vital for enabling energy transition technologies of the future. Power hardware-in-the-Loop (PHIL) test bed can be used to validate such systems cost-effectively and time-efficiently. In general, the Real Time Digital Twin (RTDT) is a virtual representation of the PES and its operating environment that...

conference paper 2023

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Fault Location Algorithm for Multi-Terminal Radial Medium Voltage DC Microgrid

Nougain, V. (author), Mishra, Sukumar (author), Nag, Soumya Shubhra (author), Lekić, A. (author)

Accurately locating the fault helps in the rapid restoration of the isolated line back into the system. This article proposes a novel communication-based multi-terminal method to locate the fault in a radial medium voltage DC (MVDC) microgrid. A time-domain based algorithm is proposed which applies to an MVDC system with different possible...

journal article 2023

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Post DC Fault Circulating Current Suppression Control

Kamat Tarcar, R. (author), Shetgaonkar, A.D. (author), Popov, M. (author), van der Meijden, M.A.M.M. (author), Winter, Wilhelm (author), Ndreko, M. (author), Dimitrovski, R. (author), Burkhardt, Matthias (author), Lekić, A. (author)

The radial topology of the Multi-terminal High Voltage Direct Current (MTDC) power system is a preferred connection for the gigawatt- renewable power due to its scalability and reliability. However, a radial topology with a metallic return bipolar converter configuration MTDC network possesses technical challenges regarding DC fault current...

conference paper 2023

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Impact of Virtual Synchronous Generators on Power System Frequency Dynamics

Fu, A. (author), Lekić, A. (author), Kontis, Eleftherios O. (author), Malamaki, Kyriaki-Nefeli D. (author), Kryonidis, Georgios C. (author), Mauricio, Juan Manuel (author), Demoulias, Charis S. (author), Cvetkovic, M. (author)

This paper deals with a systematic assessment of the power system frequency dynamics under high penetration of converter-interfaced renewable energy sources (CI-RESs). Specifically, the concept of the virtual synchronous generator (VSG) is implemented in the CI-RESs located at the transmission system (TS) side and/or the distribution network (DN...

conference paper 2023

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High-frequency transformer winding model with adequate protection

Nasirpour, F. (author), Heidary, Amir (author), Ghaffarian Niasar, M. (author), Lekić, A. (author), Popov, M. (author)

High local electric field intensity in transformer windings originating from transient signals is one of the reasons for transformer failures. Due to the integration of renewable energy sources into the power grids and the increased number of transients, the likelihood of transformer catastrophic failure increases accordingly. Therefore, to...

journal article 2023

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Zero-sequence current suppression control for fault current damper based on model predictive control

Shetgaonkar, A.D. (author), Popov, M. (author), Palensky, P. (author), Lekić, A. (author)

In a multi-terminal direct current (MTdc) system based on a modular multilevel converter (MMC), high-speed and large interruption capability direct current circuit breakers (dc CBs) are required for dc fault interruption. However, commercializing these breakers is challenging, especially offshore, due to the large footprint of the surge...

journal article 2023

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Transformer Resonance: Reasons, Modeling Approaches, Solutions

Heidary, Amir (author), Ghaffarian Niasar, M. (author), Popov, M. (author), Lekić, A. (author)

Due to the extension of the power grid with many complex and compact pieces of power equipment, transformers will be more exposed to fast transient, resulting from various resonance conditions. Transformer resonance can result in severe overvoltage on internal parts of the winding, leading to insulation failure and, consequently, transformer...

journal article 2023

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Novel busbar protection scheme for impedance-earthed distribution networks

Jankovski, Milan (author), Popov, M. (author), Godefrooi, Joey (author), Parabirsing, Evita (author), Wierenga, Ernst (author), Lekić, A. (author)

Due to the vast number of substations at the distribution level and increased costs of differential busbar protection, DSOs are in search of cost-effective protection schemes for busbar protection. This includes the use of various communication-based protection schemes, such as the reverse-blocking schemes used at Stedin. However, due to...

journal article 2023

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Distribution Network Reconfiguration Considering the Impacts of Local Renewable Generation and External Power Grid

Li, H. (author), Lekić, A. (author), Li, Shan (author), Jiang, Dongrong (author), Guo, Qiang (author), Zhou, Lin (author)

The distribution network (DN) reconfiguration is a well-known optimal power flow (OPF) problem. However, with the transition of DN from 'passive' to 'active', new technical challenges arise in DN reconfiguration. This article addresses two key issues in this regard. Firstly, the integration of local renewable generation (LRG) introduces...

journal article 2023

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Two-layer control structure for enhancing frequency stability of the MTDC system

Stojković, J. (author), Shetgaonkar, A.D. (author), Stefanov, Predrag (author), Lekić, A. (author)

This paper explores the possibilities of providing fast frequency support as an emergency support service to the disturbed AC system through the MTDC grid. A two-layer hierarchical control structure of the MTDC grid is proposed to assure the minimum cost of the frequency control actions, the minimum voltage deviations, or the minimal impact...

journal article 2023

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Interoperability of classical and advanced controllers in MMC based MTDC power system

Liu, L. (author), Shetgaonkar, A.D. (author), Lekić, A. (author)

This paper presents the modular-multilevel-converter (MMC) control interoperability (IOP) and interaction within the High Voltage Direct Current (HVDC)-based power system. IOP is a crucial issue in the large-scale HVDC grid with different suppliers. To accommodate future multi-vendor HVDC grids developments, this article comprehensively...

journal article 2023

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Model predictive control and protection of MMC-based MTDC power systems

Shetgaonkar, A.D. (author), Liu, L. (author), Lekić, A. (author), Popov, M. (author), Palensky, P. (author)

Meshed offshore grids (MOGs) present a viable option for a reliable bulk power transmission topology. The station-level control of MOGs requires faster dynamics along with multiple objective functions, which is realized by the model predictive control (MPC). This paper provides control, and protection design for the Modular Multilevel...

journal article 2023

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Robust Traveling Wave-based Protection Scheme For Multiterminal DC Grids

Liu, L. (author), Lekić, A. (author), Popov, M. (author)

The DC transmission line protection technology is crucial for the development of multi-terminal Voltage Source Converter (VSC)-based HVDC systems. This article proposes a robust non-unit traveling wave protection (TWP), which deals with the DC fault area identification and fault type discrimination for high impedance fault...

journal article 2023

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The principles of controlled DC reactor fault current limiter for battery energy storage protection

Heidary, Amir (author), Popov, M. (author), Moghim, Ali (author), Ghaffarian Niasar, M. (author), Lekić, A. (author)

The significance of battery energy storage systems (BESSs) technology has been growing rapidly, mostly due to the need for microgrid applications and the integration of renewables. Relevant to the importance of utilization of BESS in microgrids, the protection of the BESS during microgrid faults has become a concern too. The short circuit in...

journal article 2023

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Analytical Overvoltage and Power-Sharing Control Method for Photovoltaic-Based Low-Voltage Islanded Microgrid

Bakhshi-Jafarabadi, Reza (author), Lekić, A. (author), Dehghan Marvasti, F. (author), de Jesus Chavez, Jose (author), Popov, M. (author)

Overvoltage instability is a growing concern in a standalone low-voltage (LV) microgrid (MG) with non-dispatchable intermittent renewable energies such as residential and commercial photovoltaic generators (PVGs). Several overvoltage controllers used in PV arrays have adopted the concept of standard deviation from the maximum power point (MPP...

journal article 2023

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Sliding Mode Control of the MMC-based Power System

Aghahadi, Morteza (author), Piegari, Luigi (author), Lekić, A. (author), Shetgaonkar, A.D. (author)

The modular multilevel converter has become a popular topology for many applications in medium and high-power conversion systems such as multi-terminal direct current power systems. In this paper, Modular multilevel converter structure and related equations are presented. Then, control methods for circulating current, output current, and...

conference paper 2022