20 citations · 60 across the 27 of their papers we have counts for
27 papers
From Symmetry to Stability: Quantifying Converter Grid Impedance Asymmetry as Indicator of Stability Margin
Chirag Ramgopal Shah, Marta Molinas, Sjur Føyen +1
Although symmetricity in the converter controller is desirable for robust stability margins, a direct link between system-level asymmetricity and instability has yet to be clearly…
An Extended Admittance Modeling Method with Synchronization Node for Stability Assessment of Converters-Interlinked System
Haoxiang Zong, Chen Zhang, Marta Molinas
Diverse synchronization dynamics within the grid-following (GFL)/grid-forming (GFM) converters-interlinked system are prone to induce oscillatory instabilities. To quantify their s…
A Multilayer Eigen-Sensitivity Method Using Loop Gain Model for Oscillation Diagnosis of Converter-Based System
Haoxiang Zong, Chen Zhang, Xu Cai +1
Loop gain-based eigen-sensitivity (LGES) is a useful frequency-domain tool for oscillation diagnosis of converter-based system. However, the existing theory is still scant in two a…
Marine Integrated Energy Microgrids
Chendan Li, Muzaidi Othman, Nor Baizura Ahamad +1
Marine sector decarbonization is another important battlefield for meeting the goal of climate action and ensuring the fulfillment of ambitions for a zero-emission society. Driven…
Three-Port Impedance Model and Validation of VSCs for Stability Analysis
Haoxiang Zong, Chen Zhang, Xu Cai +1
Modern power system is undergoing a paradigm shift from the synchronous generators-based system to the power electronics converters-dominated system. With the high penetration of c…
A Practical Method for Automated Modeling and Parametric Stability Analysis of VSC with Periodical Steady State
Chen Zhang, Jon Are Suul, Marta Molinas
Linear Time Periodic (LTP) framework-based analysis of Voltage Source Converters (VSCs) is becoming popular, a driven factor is that many of the existing VSC applications inevitabl…
Impedance Network of Interconnected Power Electronics Systems: Impedance Operator and Stability Criterion
Chen Zhang, Marta Molinas, Atle Rygg +1
Impedance is an intuitive and efficient way for dynamic representation of power electronics devices. One of the evident strengths, when compared to other small-signal methods, is t…
EEG-based Subjects Identification based on Biometrics of Imagined Speech using EMD
Luis Alfredo Moctezuma, Marta Molinas
When brain activity is translated into commands for real applications, the potential for human capacities augmentation is promising. In this paper, EMD is used to decompose EEG sig…
Impact of Digital Time Delay on the Stable Grid Hosting Capacity of Large-scale Centralized Photovoltaic Plant
Jinhong Liu, Lin Zhou, Marta Molinas
In view of the trend towards extensive application of digital controllers in the PV inverter of large-scale centralized photovoltaic (LSCPV) plant and the increasing number of grid…
Understanding the Nonlinear Behavior and Frequency Stability of a Grid-synchronized VSC Under Grid Voltage Dips
Chen Zhang, Marta Molinas, Xu Cai +1
Transients of a grid-synchronized voltage source converter (VSC) are closely related to over- currents and voltages occurred under large disturbances (e.g. a grid fault). Previous…
Comparison of frequency estimation methods for wave energy control
Paula B. Garcia-Rosa, John V. Ringwood, Olav B. Fosso +1
A number of wave energy controllers tune the power take-off (PTO) system to the frequency of incident waves. Since real ocean waves are non-stationary by nature and not defined by…
Method for Mode Mixing Separation in Empirical Mode Decomposition
Olav B. Fosso, Marta Molinas
The Empirical Mode Decomposition (EMD) is a signal analysis method that separates multi-component signals into single oscillatory modes called intrinsic mode functions (IMFs), each…
Harmonic State Space Modeling of a Three-Phase Modular Multilevel Converter
Jing Lyu, Marta Molinas, Xu Cai
This paper presents the harmonic state space (HSS) modeling of a three-phase modular multilevel converter (MMC). MMC is a converter system with a typical multi-frequency response d…
A simple method for shifting local dq impedance models to a global reference frame for stability analysis
Atle Rygg, Marta Molinas, Eneko Unamuno +2
Impedance-based stability analysis in the dq-domain is a widely applied method for power electronic dominated systems. An inconvenient property with this method is that impedance m…
Impedance Analysis of Modular Multilevel Converter Based on Harmonic State-Space Modeling Method
Jing Lyu, Qiang Chen, Xu Cai +1
The small-signal impedance modeling of modular multilevel converter (MMC) is the key for analyzing resonance and stability of MMC-based ac power electronics systems. MMC is a conve…
Non-parametric Impedance based Stability and Controller Bandwidth Extraction from Impedance Measurements of HVDC-connected Wind Farms
Mohammad Amin, Marta Molinas
Impedance measurements have been widely used with the Nyquist plot to estimate the stability of interconnected power systems. Being a black-box method for equivalent and aggregated…
Model Predictive Control of Voltage Source Converter in a HVDC System
Mohammad Amin, Marta Molinas
Model Predictive Control (MPC) method is a class of advanced control techniques most widely applied in industry. The major advantages of the MPC are its straightforward procedure w…
Accurate and reduced SISO Sequence Impedance Models of Grid-tied Voltage Source Converter for Small Signal Stability Analysis
Chen Zhang, Xu Cai, Atle Rygg +1
Impedance models are widely used in assessing small signal stability of grid-tied voltage source converter (VSC) systems. Recent research has proven that impedance models of grid-t…
Augmented Sequence Impedance Networks of Grid-tied Voltage Source Converter for Stability Analysis
Chen Zhang, Xu Cai, Atle Rygg +1
Impedance-based stability analysis is appealing in the case of Single-Input Single-Output (SISO) systems. However, in the case of grid-tied voltage source converter (VSC) systems,…
Coupled and decoupled impedance models compared in power electronics systems
Atle Rygg, Marta Molinas, Chen Zhang +1
This paper provides a comparative analysis of impedance models for power electronic converters and systems for the purpose of stability investigations. Such models can be divided i…
A modified sequence domain impedance definition and its equivalence to the dq-domain impedance definition for the stability analysis of AC power electronic systems
Atle Rygg, Marta Molinas, Zhang Chen +1
Representations of AC power systems by frequency dependent impedance equivalents is an emerging technique in the dynamic analysis of power systems including power electronic conver…
On wind Turbine failure detection from measurements of phase currents: a permutation entropy approach
Sumit Kumar Ram, Geir Kulia, Marta Molinas
This article presents the applicability of Permutation Entropy based complexity measure of a time series for detection of fault in wind turbines. A set of electrical data from one…
Entropic Empirical Mode Decomposition
Sumit Kumar Ram, Marta Molinas
Empirical Mode Decomposition(EMD) is an adaptive data analysis technique for analyzing nonlinear and nonstationary data[1]. EMD decomposes the original data into a number of Intrin…
Search-Enhanced Instantaneous Frequency Detection Algorithm: A Preliminary Design
Phen Chiak See, Marta Molinas
This paper presents a method developed for finding sinusoidal components within a nonlinear non-stationary time-series data using Genetic Algorithm (GA) (a global optimization tech…