Mario Paolone

• Prof., PhD
• Professor (Full) at Swiss Federal Institute of Technology in Lausanne

This paper presents the experimental validation of a framework for the coordinated dispatch and control of multiple active distribution networks (ADNs) hosting distributed energy resource (DER). We show that the presented method, which builds further on work done in [1], effectively allows to control multiple ADNs in a distributed way to ensure the...

This paper presents a grid-aware probabilistic approach to compute the aggregated flexibility at the grid connection point (GCP) of active distribution networks (ADNs) to allow the participation of DERs in ancillary services (AS) markets. Specifically an optimal power flow (OPF) method using a linear network model is used to compute the aggregated...

This paper proposes an optimal, grid-aware control framework for the islanding, island-operation and resynchronisation of hybrid AC/DC microgrids. The optimal control framework is based on a formally derived linearized load-flow model for multiterminal hybrid AC/DC networks. The load flow model integrates the AC grid, DC grid, and interfacing conve...

Accurate intraday solar irradiance forecasting is crucial for optimizing dispatch planning and electricity trading. For this purpose, we introduce a novel and effective approach that includes three distinguishing components from the literature: 1) the uncommon use of single-frame public camera imagery; 2) solar irradiance time series scaled with a...

The increasing integration of Distributed Energy Resources (DERs) within power distribution grids introduces uncertainties that can result in control and operation issues such as line congestions, reduced voltage quality and increased grid imbalance cost. Existing research tackles these issues through topology reconfiguration or reinforcement of ex...

The second-order generalized integrator (SOGI), which can be used to attenuate the self-interference of the fundamental tone, is unable to reject DC offsets on the input signal. Consequently, the performance of any SOGI based synchrophasor estimation (SE) technique might be compromised in the presence of such DC components. The current work present...

In this paper, we study a suitable experimental design of electrochemical impedance spectroscopy (EIS) to reduce the number of frequency points while not significantly affecting the uncertainties of the estimated cell's equivalent circuit model (ECM) parameters. It is based on an E-optimal experimental design that aims to maximize the information a...

This paper proposes and experimentally validates a grid-aware scheduling and control framework for Electric Vehicle Charging Stations (EVCSs) for dispatching the operation of active distribution networks (ADNs). The framework consists of two stages. In the first stage (day-ahead), we determine an optimal 24-hour power schedule at the grid connectio...

Traditional magnetic levitation trains (maglev) generally use two or three separate systems to perform propulsion, levitation, and guidance (PLG) functionalities. Linear electro-magnetic motors (LEMs) may be used for propulsion, electro-magnetic suspension (EMS), or electrodynamic suspension (EDS) for levitation and guidance. Although considerable...

This paper proposes a method for the Harmonic Stability Assessment (HSA) of power systems with a high share of Converter-Interfaced Distributed Energy Resources (CIDERs). To this end, the Harmonic State-Space (HSS) model of a generic power system is formulated by combining the HSS models of the resources and the grid in closed-loop configuration. T...

In Part I of this paper a method for the Harmonic Stability Assessment (HSA) of power systems with a high share of Converter-Interfaced Distributed Energy Resources (CIDERs) was proposed. Specifically, the Harmonic State-Space (HSS) model of a generic power system is derived through combination of the components’ HSS models. The HSS models of CIDER...

With the integration of distributed energy resources and the trend towards low-inertia power grids, the frequency and severity of grid dynamics is expected to increase. Conventional phasor-based signal processing methods are proving to be insufficient in the analysis of non-stationary AC voltage and current waveforms, while the computational comple...

Key operational and protection functions of power systems (e.g., optimal power flow scheduling and control, state estimation (SE), protection, and fault location) rely on the availability of models to represent the system’s behavior under different operating conditions. Power system models require knowledge of the components’ electrical parameters...

With advances in industrial data communication technologies, MW-scale PV parks increasingly depend on communication-based coordination among Power Electronic Converters (PECs) to ensure precise voltage regulation and stability, especially during grid fault events. However, Communication Delay (CD) can degrade voltage control, leading to sustained o...

Data centers are large electricity consumers due to the high consumption needs of servers and their cooling systems. Given the current crypto-currency and artificial intelligence trends, the data center electricity demand is bound to grow significantly. With the electricity sector being responsible for a large share of global greenhouse gas (GHG) e...

The concept of synchro-waveforms has recently emerged as a promising frontier in power system monitoring and data-driven applications. By providing access to raw waveform samples, synchro-waveforms can capture not only the typical major disturbances but also the seemingly minor, yet sometimes highly informative, disturbances in voltage and current...

Literature on linear induction motors (LIMs) has proposed several approaches to model the behavior of such devices for different applications. In terms of accuracy and fidelity, field analysis-based models are the most relevant. Closed-form or numerical solutions can be derived, based on the complexity of the model and the underlying hypotheses. In...

This article describes a simultaneous and decoupled scheme for the control of levitation and propulsion forces of single-sided linear induction motors (SLIMs). The proposed control scheme utilizes a highly accurate SLIM analytical model to ensure the operation of the motor at the best efficiency point while achieving lift and thrust forces decoupli...

This paper proposes a generic and unified model of the power flow (PF) problem for multiterminal hybrid AC/DC networks. The proposed model is an extension of the standard AC-PF. The DC network is treated as an AC one and, in addition to the Slack, PV and PQ nodes, four new node types are introduced to model the DC buses and the buses connecting the...

In this paper, we present a model for the analytical computation of the power flow sensitivity coefficients (SCs) for hybrid AC/DC networks. The SCs are defined as the partial derivates of the nodal voltages with respect to the active and reactive power injections and are used in the literature to model the grid constraints in a linear way (e.g. in...

In recent decades, the electricity industry has undergone a significant transformation from a vertically integrated supply system to a market-regulated structure. This shift, along with the intermittent nature of increasingly prevalent non-dispatchable renewable energy sources, induces system operators to redistribute portions of the power generati...

Microgrids and, in general, active distribution networks require ultra-short-term prediction, i.e., for sub-second time scales, for specific control decisions. Conventional forecasting methodologies are not effective at such time scales. To address this issue, we propose a non-parametric method for computing ultra short-term prediction intervals (P...

This article describes a field-based analytical model of single-sided linear induction motors (SLIMs) that explicitly and simultaneously considers the following effects: finite motor length, magnetomotive force mmf space harmonics, slot effect, edge effect, and tail effect. The derived closed-form solution of the system's differential equations mak...

This paper proposes a method for the Harmonic Stability Assessment (HSA) of power systems with a high share of Converter-Interfaced Distributed Energy Resources (CIDERs). To this end, the Harmonic State-Space (HSS) model of a generic power system is formulated by combining the HSS models of the resources and the grid in closed-loop configuration. T...

In Part I of this paper a method for the Harmonic Stability Assessment (HSA) of power systems with a high share of Converter-Interfaced Distributed Energy Resources (CIDERs) was proposed. Specifically, the Harmonic State-Space (HSS) model of a generic power system is derived through combination of the components HSS models. The HSS models of CIDERs...

This paper presents a rigorous assessment of natural frequencies associated with fault-originated travelling waves in power networks, factoring in the presence of multiple junctions and branches. The proposed assessment exploits the Baum-Liu-Tesche (BLT) equation. An enhanced fault location accuracy is consequently attained leveraging rectified nat...

With the integration of distributed energy resources and the trend towards low-inertia power grids, the frequency and severity of grid dynamics is expected to increase. Conventional phasor-based signal processing methods are proving to be insufficient in the analysis of non-stationary AC voltage and current waveforms, while the computational comple...

Electrochemical Impedance Spectroscopy (EIS) and Equivalent Circuit Models (ECMs) are widely used to characterize the impedance and estimate parameters of electrochemical systems such as batteries. We use a generic ECM with ten parameters grouped to model different frequency regions of the Li-ion cell's impedance spectrum. We derive a noise covaria...

Microgrids and, in general, active distribution networks require ultra-short-term prediction, i.e., for sub-second time scales, for specific control decisions. Conventional forecasting methodologies are not effective at such time scales. To address this issue, we propose a non-parametric method for computing ultra short-term prediction intervals (P...

The number of transient operations in hydraulic machinery connected to power grid, notably start-ups and shut-downs, has observed a substantial increase in recent decades, primarily driven by the global shift towards intermittent renewable energy sources. Simultaneously, advancements in MW power converter technology and its cost-effectiveness have...

This paper proposes a grid-aware scheduling and control framework for Electric Vehicle Charging Stations (EVCSs) for dispatching the operation of an active power distribution network. The framework consists of two stages. In the first stage, we determine an optimal day-ahead power schedule at the grid connection point (GCP), referred to as the disp...

In Part-I, we presented an optimal day-ahead scheduling scheme for dispatching active distribution networks accounting for the flexibility provided by electric vehicle charging stations (EVCSs) and other controllable resources such as battery energy storage systems (BESSs). Part-II presents the intra-day control layer for tracking the dispatch plan...

Recently, the authors of this paper proposed a method for the Harmonic Power-Flow (HPF) calculus in polyphase grids with widespread deployment of Converter-Interfaced Distributed Energy Resources (CIDERs). The HPF problem was formulated by integrating the hybrid nodal equations of the grid with a detailed representation of the CIDERs hardware, sens...

Linear electromagnetic motors (LEMs) have been proposed, developed and used to propel high-speed (i.e. speed > 100 m/s) levitating vehicles. However, few real implementations have demonstrated the feasibility of these machines at such speeds. Furthermore, LEMs are expected to be enabling technologies for levitating vehicles traveling at near sonic...

This paper proposes a methodology to optimize the dispatch and reserve between multiple units in a Hydroelectric Power Plant (HPP) that makes use of the Hydraulic Short Circuit (HSC) operating mode. HSC allows for the simultaneous generation and pumping from different units of the same plant. The objective of optimal dispatching is to maximize effi...

Recently, the authors of this paper proposed a method for the Harmonic Power-Flow (HPF) calculus in polyphase grids with widespread deployment of Converter-Interfaced Distributed Energy Resources (CIDERs). The problem was formulated by integrating the hybrid nodal equations of the grid with a detailed representation of the s hardware, sensing, and...

Presently, many utility-scale inverter-based resources (IBRs) are in remote areas of the system where often there is sparse transmission and few synchronous generating resources. This interconnection scenario invariably leads to a low short-circuit current availability at the point of common coupling (PCC) of the IBR. Additionally, most new IBRs ar...

This paper presents the experimental validation of a linear recursive state estimation (SE) process for hybrid AC/DC microgrids proposed in the authors' previous work. The SE uses a unified and linear measurement model that relies on the use of synchronized AC and DC measurements along with the complex modulation index of voltage source converters...

Increasing adoption of smart meters and phasor measurement units (PMUs) in power distribution networks are enabling the adoption of data-driven/model-less control schemes to mitigate grid issues such as over/under voltages and power-flow congestions. However, such a scheme can lead to infeasible/inaccurate control decisions due to measurement inacc...

The paper proposes a synchropahsor estimation (SE) algorithm that leverages the use of a delayed in-quadrature complex signal to mitigate the self-interference of the fundamental tone. The estimator, which uses a three-point IpDFT combined with a three-cycle Hanning window, incorporates a new detection mechanism to iteratively estimate and remove t...

As the share of Converter-Interfaced Distributed Energy Resources (CIDERs) in power distribution systems increases, hybrid AC/DC distribution systems are drawing more interest. Indeed, CIDERs usually rely on DC power and hybrid AC/DC grids with few Network-Interfacing Converters (NICs) are a promising solution to decrease installation costs and con...

This Github repository (https://github.com/DESL-EPFL/Harmonic-Power-Flow-Method) comprehends a Matlab project for the Harmonic Power-Flow (HPF) calculus in power systems with a high share of Converter-Interfaced Distributed Energy Resources. The project consists of the Matlab Code performing the HPF study, along with the Simulink models for its val...

The paper proposes a synchropahsor estimation (SE) algorithm that leverages the use of a delayed in-quadrature complex signal to mitigate the self-interference of the fundamental tone. The estimator, which uses a three-point IpDFT combined with a three-cycle Hanning window, incorporates a new detection mechanism to iteratively estimate and remove t...

Electromagnetic time reversal (EMTR)-based methods have been applied to the problem of fault location in power networks since 2012. Over the past decade, considerable theoretical investigations have led to a continuous improvement of the EMTR method in terms of fault location accuracy and efficiency. Meanwhile, different full-scale experiments, inc...

This technical document summarizes recent advancements on spatio-temporal data-driven and machine learning methods for static and dynamic security assessment, and their particular use cases. It is a collective effort of different research groups with the aim of providing transmission system operators (TSOs) with innovative tools and ideas for their...

Measurement-rich power distribution networks may enable distribution system operators (DSOs) to adopt model-less and measurement-based monitoring and control of distributed energy resources (DERs) for mitigating grid issues such as over/under voltages and lines congestions. However, measurement-based monitoring and control applications may lead to...

This paper proposes and experimentally validates a joint control and scheduling framework for a grid-forming converter-interfaced Battery Energy Storage Systems (BESSs) providing multiple services to the electrical grid. The framework is designed to dispatch the operation of a distribution feeder hosting heterogeneous prosumers according to a dispa...

The evaluation of the signal frequency and Rate of Change of Frequency (RoCoF) from voltage or current waveforms is used for critical grid control, monitoring and protection applications. However, when step changes in the amplitude or phase of the signal occur, conventional frequency and RoCoF estimation methods, typically based on phasor models, a...

This work presents an optimization framework to aggregate the power and energy flexibilities in an interconnected power distribution systems. The aggregation framework is used to compute the day-ahead dispatch plans of multiple and interconnected distribution grids operating at different voltage levels. Specifically, the proposed framework optimize...

Power distribution systems experience a large-scale integration of Converter-Interfaced Distributed Energy Resources (CIDERs). As acknowledged by recent literature, the interaction of individual CIDER components and different CIDERs through the grid can lead to undesirable amplification of harmonic frequencies and, ultimately, compromise the distri...

Dispatching active distribution networks (ADNs) is an energy-intensive application that, if implemented via battery-energy storage systems (BESSs), can require a large capacity of these assets in order to fully balance the uncertainties caused by the stochastic demand and generation. The insufficient capacity of the BESSs often leads to their state...

The problem of securely reconnecting active distribution networks (ADNs) – e.g. microgrids – to their upstream grids at the point of common coupling (PCC) has been extensively discussed by the existing literature. The latter is commonly referred to as resynchronization and has to be done with care in order to avoid large transient current flows res...

This paper presents a combined framework for power distribution network expansion planning (DNEP) and energy storage systems (ESSs) allocation in active distribution networks (ADNs) hosting large amount of photovoltaic (PV) generations and loads. The proposed DNEP ensures the reliable operation of the targeted ADN with the objective of achieving it...

Hydropower plants (HPPs) are acknowledged to be fundamental assets to provide generation flexibility to power systems hosting substantial amount of stochastic renewable energy sources. Within this context, providing this flexibility enforces HPP units to cross-over transient operating conditions or to operate in off-design conditions. The evaluatio...

With specific reference to the HPP start-up sequence, the conventional process requires to operate the runner in a particular operating regime called Speed-No-Load (SNL) that is detrimental for the runner. Thanks to last decade’s improvements in MW-class power electronics, new generators’ technologies have emerged providing an additional degree of...