Electronic Loads Research Articles

Magnetically Integrated Multiport Converter for Energy Management in DC-Powered Buildings

Multiport converters have gained attention in the last few years as a key component for dc-powered buildings, more electric aircraft, and maritime applications. For buildings, the prevalence of dc appliances and electronic loads increases the need for efficient integration with both ac grid and local generation. Ac-dc multiport converters play an important role in this integration because dc distribution has been considered for power integration in modern buildings. In addition, the growing complexity of loads and sources within buildings has driven interest in developing flexible solutions to provide highly efficient integration. Furthermore, ongoing developments in standardization for in-building dc grids underscore the importance of considering specific requirements for future designs. This paper proposes a multiport power converter (ac/dc/dc) to integrate dc-powered buildings into an ac grid. By providing a multiport solution, it is possible to reduce the power processing stages and the component count. To evaluate the effectiveness of this concept, a 5-kW prototype was built and tested, including efficiency evaluation. In addition, emerging standards are discussed to tailor the power converter design for building applications.

Design of solar and energy storage systems fed reduced switch multilevel converter with flower pollination optimization

In the present situation, the growing use of power electronic devices and non-linear loads has led to power quality (PQ) issues, including harmonics and poor power factor, which adversely affect the distribution network. This study contributes a design of shunt active power filter, powered by solar energy and energy storage systems, to address these PQ issues. To minimize losses, a five-level reduced-switch voltage source converter has been considered. Additionally, a neural network-based reference signal generation method is used, eliminating the need for conventional synchronous reference frame and active-reactive power theories, along with their complex abc and αβ0 transformations. This work also includes the optimal selection of the shunt filter and the gain parameters for the proportional-integral-derivative (PID) controller used in the shunt and battery control system. These parameters, along with the weights and biases of the neural network, are optimally determined using a nature-inspired flower pollination optimization algorithm.The proposed system has three primary objectives: (1) stabilizing the voltage across the DC bus capacitor, (2) reducing total harmonic distortion (THD) and improving the power factor (PF), and (3) ensuring the power management under the varying irradiation and load conditions. The effectiveness of the proposed system is evaluated through three testing scenarios, with results compared to conventional SRF and pq methods using a proportional-integral controller (PIC). The analysis reveals that the THD for the case studies is 3.32 %, 2.93 %, and 3.98 %, significantly lower than the other techniques compared. Additionally, the PF is nearly at unity, with a lower settling time of 0.05 s for the DC bus voltage.

Battery Deactivation for Safe and Efficient Recycling

With the substantial increase in the demand for lithium-ion batteries (LIBs) for the adoption of electrification to reduce CO2 emission, safe and efficient recycling of spent LIBs is essential to utilize LIBs sustainably1. In hydrometallurgy-based or direct LIB recycling systems, which are expected to become mainstream in the future because of their low environmental impacts, deactivation is a crucial pretreatment step to safely handle LIBs during the processes2, 3. However, a common deactivation method, in which an external short circuit is induced using electronic loads or conductive liquid, cannot deactivate LIBs with disconnected electrical circuits or metallic Li plating on the negative electrode surface, despite their high safety risks.We propose the advanced deactivation method, injecting a redox mediator (RM) solution inside the LIBs. The RM delivers electrons from the negative electrode to the positive electrode by cycling the reduction and oxidation on the negative and positive electrodes, respectively (redox shuttle reaction), resulting in discharging LIBs. In other words, the RM causes a short circuit inside the LIB. Therefore, it is possible to discharge a LIB that cannot be discharged externally, for example, a LIB with disconnected electrical circuits due to a safety device operation. Furthermore, the RM can strip Li metal plated on the negative electrode even though it is “dead lithium.” This unique characteristic contributes to the improvement in the safety and the Li collection rate in the recycling processes. Additionally, in this presentation, the deactivation mechanism of LIBs and its relationship with the electrochemical properties of the RMs will be discussed. The present findings will be beneficial and helpful for designing RMs for deactivation of more and more diversified spent LIBs. References J. Neumann, et al.: "Recycling of Lithium‐Ion Batteries—Current State of the Art, Circular Economy, and Next Generation Recycling" Adv. Energy Mater. 12, (2022). A. Kwade, et al.: "Recycling of lithium-ion batteries" The LithoRec Way, Switzerland: Springler International Publishing AG (2018). H. Rouhi, et al.: "Voltage behavior in lithium-ion batteries after electrochemical discharge and its implications on the safety of recycling processes" Journal of Energy Storage 35, (2021).

Inaccuracies and Uncertainties for Harmonic Estimation in Distribution Networks

The proliferation of electronic loads has led to a substantial increase in harmonic emissions within low-voltage distribution networks. The accurate estimation of the expected levels of harmonics in a network is a daunting task for network operators. Stochastic-based harmonic estimation models can offer a comprehensive assessment of the expected levels of harmonics in the presence of existing and future loads, including electric vehicles and smart-grid-enabled devices. Such models offer a valuable tool for network operators to assess the potential impact of harmonics on future networks and to create sustainable design solutions to meet the increasing demand for electricity while achieving net zero targets. However, several variables associated with these estimations models involve a level of uncertainty due to their stochastic nature, leading to inaccuracies in the estimations. This paper aims to provide a more realistic estimate of these uncertainties in order to improve the outcomes of harmonic estimation models for the development of sustainable distribution networks.

Nonlinear Loads Modelling and Harmonics Analysis: A Review

Abstract: In modern life, the applications of nonlinear loads are increasing, especially electronic loads, such as computers, monitors, and battery chargers. Moreover, the usage of semiconductors has increased in modern lighting systems, such as LED lamps and dimmers which are used to control the lighting level. Nonlinear loads may also be in the form of variable speed drive or arc furnace loads. Due to the spread of nonlinear loads, large amounts of harmonics are generated. To study the harmonics of nonlinear loads, it is essential to represent nonlinear loads by their equivalent models in the simulation programs. This paper presents a comprehensive review of modeling methods of nonlinear loads, including time domain methods, frequency domain methods, and state space methods. Equivalent circuits are presented for different types of nonlinear loads, including static loads, dynamic loads and arc furnace loads. The paper also presents the harmonic analysis performed by the Fourier transform of different types of nonlinear loads, including harmonic percentage and its angle. This paper is considered as a comprehensive reference for researchers and engineers to model nonlinear loads and is useful in power system planning for connecting nonlinear loads where mixing nonlinear loads of similar harmonic profiles causes worse situations. Moreover, knowing the nonlinear load profile will help in the suitable mixing of linear loads to achieve lower harmonics levels.

Autonomous Finite-Time Backstepping Control for Decentralized Economic Power Dispatch in DC Microgrids Toward Large-Signal Stability

The power electronic loads usually behave as constant power loads (CPLs) in DC microgrids (MGs), which degrades the system stability due to their high-order non-linearity and negative impedance characteristics. Furthermore, the stability concern will be more complicated for the distributed generators (DGs) in DC MGs considering both economic efficiency and plug-and-play performance. In this paper, an autonomous finite-time backstepping controller (FTBC) for decentralized economic power dispatch and precise DC bus voltage regulation of a DC MG is proposed. The high-order nonlinear disturbance observer (HONDO) technique is adopted to estimate the power exchanges between the DGs and loads. So that the decentralized economic power dispatch and rapid voltage regulation can be achieved without any extra output current sensors. In addition, the use of HONDO improves the system's dynamic performance by estimating the disturbances and system uncertainties, and the FTBC guarantees the bus voltage tightly tracking within a finite-time convergence. A rigorous stability analysis is performed to prove the large-signal stability of the regulated system, and some simulations and experiments are carried out.

A novel fuzzy-logic controller-MDsUPQC topology for power quality improvement in multi-feeder distribution system

In the current situation, the significant usage of massive non-linear functioned power electronic loads has been increased in domestic and industrial applications. The main problem of power-quality (PQ) deterioration in both voltage quality and current quality from nominal values and also damaging the single/multi feeder distribution systems. The major contribution is to alleviate the PQ issues by employing novel multi-devices unified power-quality conditioner (MDsUPQC) topology in a multi-feeder distribution system. This MDsUPQC comprises multiple voltage source inverter (VSI) devices connected with a common direct current-link (DC-link) capacitor which is controlled by a proportional-integral (PI) controller. However, this controller has some technical issues that are not suited for the regulation of common DC voltage at the desired level because of improper selection of gain values. The contribution of this work is proposing an intelligent fuzzy-logic (FL) DC-link controller-driven MDsUPQC device which evidences the intelligent knowledge base for better regulation of PQ issues. The technique and performance of the suggested strategy for PQ improvement, load sharing between feeders, and simulation results are presented with comparative analysis utilizing the MATLAB/Simulink software tool.

Determination losses and estimate life of distribution transformers with three computational, measurement and simulation methods, despite harmonic loads

Transformers are the basic and valuable equipment of electricity network. Transformers correct function has important role in reliability of network .distribution transformers are designed for work at nominal frequency and full sinus current. Application of nonlinear loads in recent decades, such as power electronic loads, caused higher levels of harmonic. This kind of load can lead to creating heat, losses and therefore cause wear of insulation and aging of transformers. To prevent these problems, nominal capacity of transformers that will feed the nonlinear load, should be reduced. In this paper the parameters affecting the loss of a single phase 15 KVA transformers with harmonic loading measurement and will be calculated with standards then The transformers with harmonic loads are simulated in MATLAB software for calculating losses Finally, the obtained results are compared. The reduction of nominal power (Derating) and transformer life and flow rate limits and losses are calculated.

ANN based smart sensing of short-term voltage stability assessment of modern power system

This study addresses the critical challenge of Short-term Voltage Stability (STVS) in the contemporary electric grid system, characterized by diverse static loads, induction motors, electronic loads, electric vehicle charging stations, and renewable energy sources. High-power sensing elements are identified for power system stability and transient measurements, and the existing system is explored for fault measurement and stability maintenance. The analysis employs an IEEE 14-bus dynamic model with two distinct load configurations. In the first configuration, the static load at bus 14 is replaced with a composite load, encompassing static loads, induction motors, electronic loads, and EV charging stations. For the second novel configuration at bus 14, the static load is substituted with a composite load and a solar photovoltaic (PV) generator operating in reactive power compensation mode. This addition of the PV generator compensates for elevated reactive power demand in the 14-bus system. The study conducts voltage stability analysis in two phases, evaluating the voltage profile and transmission line load ability in both scenarios during the first phase. In the second phase, STVS is simulated by briefly opening the circuit breaker in bus 2. The results reveal notable improvements in the voltage profile of all buses, a 6 % enhancement in power factor at bus 14 in the dynamic model with the novel configuration, and a 3 % increase in the loading factor of the IEEE Bus 14 system. The dynamic model incorporating a PV generator and composite load in bus 14 demonstrates superior STVS performance compared to the setup with only a composite load. The abstract concludes by highlighting the development of real-time voltage profile assessment using Artificial Neural Network (ANN) topology, leveraging results from the Continuous Power Flow (CPF) analysis of the novel model with a PV generator and composite load in the far end bus. This restructuring ensures a logical and clear organization, encompassing an introduction to the problem, a description of methods employed, presentation of results, and a succinct conclusion summarizing the key findings.

Performance analysis of ship mounting PV panels deployed in Sungsang Estuary and Bangka Strait, Indonesia

In an archipelago country like Indonesia, maritime transportation is essential. However, the ships, like other modes of transportation, burn fuel, contributing to CO2 emissions and negatively impacting marine life. Alternative renewable energy can help solve this problem while being environmentally friendly and cost-effective. As a result, this research describes installing PV systems to power electronic loads on a pilot ship. The supply-demand scenario was simulated using the System Advisory Model. The experiment lasted 176 days, 32 of which were still hybrid with a diesel generator, and for 144 days, electronics loads were entirely powered by PV systems. The experimental results show that the generated power consistently exceeds what is necessary. MPPT may also control the battery charging to avoid overcharging by ensuring the voltage input is always consistent. The maximum generated power is 2356 W with a peak load of 1669 W, and the average generated power is 1645 W with a load of 720.6 W. According to SIMAPRO's life cycle study results, the most significant environmental impact comes during installation due to using diesel fuel trucks and when the PV system is no longer operational since it will become a landfill, harming the ecosystem. PV systems, on the other hand, have no environmental impact during installation. Economic estimates show significant savings and, of course, profits.

An Energy-Feed Type Split-Capacitor Three-Phase Four-Wire Power Electronic Load Compatible with Various Load Demands

Energy-feed power electronic loads can precisely control the phase and magnitude of the power supply output current, achieving the emulation of loads. Moreover, they can feed energy back to the grid for energy regeneration, demonstrating significant research value. This article proposes an energy-fed power electronic load topology and control method that can realize the static and dynamic simulation of linear and non-linear loads and take into account the simulation needs of single-phase, three-phase three-wire, and three-phase four-wire loads. The main circuit uses a two-stage back-to-back AC/DC/AC structure: the front side is a three-phase four-wire split capacitor PWM rectifier bridge, which is used to simulate loads under various operating conditions; the back side is a three-phase three-wire PWM inverter bridge, which realizes the energy feeding back to the grid and reduces the waste of energy; and the intermediate side uses a split capacitor to equalize the voltage and achieve voltage stabilization. The topology is analyzed under the simulation demands of three-phase balanced, three-phase unbalanced, single-phase and non-linear loads. Finally, a MATLAB(R2022a)/Simulink simulation platform is built for a power electronic load with a rated capacity of 200 kVA. The simulation results verify the effectiveness, feasibility, and advancement of the power electronic load proposed in this article.

Battery Emulator for Coupled Electro-Thermo Powertrain Testing

Approved, DCN# 543-443-23Battery emulation systems are useful for testing and evaluating powertrain systems; but typically,only consider the electrical characteristics of a battery. Powertrains with shared cooling components/systems between batteries and power electronics would benefit from hardware-in-the-loop testing facilities that consider both the electrical and thermal aspects of energy storage. In this work a battery emulator that physically emulates both the electrical and thermal characteristics with a coupled electro-thermal powertrain testbed is demonstrated. The coupled electro-thermo model links the electrical and thermal outputs together and calculates them in real-time. The electrical model is an equivalent circuit representation of a battery making use of experimental data from tested cells. The electrical model is coupled to the thermal model through temperature-dependent parameters of the cell resistance and open circuit voltages. The thermal model is a lumped isothermal reduced order heat generation model. This model will calculate the net heat generated from the ohmic losses, entropic losses, and losses to cooling (liquid and ambient). The thermal model is coupled to the electrical model by being dependent on the cell’s state of charge and using the cell’s current and voltage outputs for its governing equations. Models are parameterized on experimental data acquired through pulsed hybrid testing. In this work, a 3.5 kWh battery pack with a discharge of 40 amps at 48 volts generating 38.4 Watts of heat is emulated in an electro-thermo powertrain testbed configured to represent an electric naval platform such as a small autonomous boat subjected to both baseline and pulsed loading. The electrical emulation is performed through a bidirectional power supply and thermal emulation through a resistive heater. The electro-thermo powertrain testbed then dissipates the emulated electrical energy through power convertors and electronic loads while the thermal energy is dissipated through a heat exchanger that also cools the power convertors. Numerical and experimental validation demonstrate that the coupled electro-thermo battery emulator is capable of accurately representing the electrical and thermal aspects of a 3.5 kWh battery. Limitations in terms ofemulating batteries at higher temperatures and current draws are discussed. Effects of scaling the coupled electro-thermo battery emulator are also presented.Acknowledgment: This work was supported in part by the Office of Naval Research under contract NO.N00014-22-C-1003DISTRIBUTION STATEMENT A. Approved for public release: distribution unlimited

Testing the Advanced Single Phase Asymmetric Cascaded Multilevel Inverter Topology using RES

This paper works on developing a model of single phase asymmetrical cascaded multilevel inverter (MLI) which couples’ renewable energy sources (RES) to the electrical or electronic loads of the AC powered transport system applications (e.g., Locomotives, Vehicles). MLI is the most important device as it is the main adaptation stage between the source and the load. Researchers are now more focused on multilevel inverters because of its numerous advantages. The prime benefit of a multilevel inverter is obtaining more output voltage levels using a smaller number of DC sources. The proposed topology for this work is asymmetric and produces 31-Levels of output which consists of 12 IGBT switches and 4 isolated dc voltage supplies V dc1 , V dc2 , V dc3 and V dc4 (Ratio of 2:4:8:16). The proposed topology has been processed by using PWM (Pulse Width Modulation) technique. Fundamental switching frequency (50HZ) has been used to achieve better quality of output voltage waveform with low harmonic distortion. The proposed topology has been explicitly and thoroughly analyzed throughout the study to demonstrate its superiority over alternative MLI topologies. Power loss analysis of the chosen MLI topology is also shown. An adequate comparison is also carried out between traditional and the proposed topologies. The comparative analysis shows that the chosen existing topology is better performed than others. According to the theoretical analysis conducted, the maximum efficiency obtained is 92.91% along with THD of 4.44% and TSV of 60 V dc . The accuracy of the proposed topology is verified through simulating the entire model in MATLAB-Simulink software.

Modified instantaneous power theory control of dynamic voltage restorer powered by photovoltaic system

<span lang="EN-US">Power quality issues have become widespread due to nonlinear electronic converters and loads. Nonlinear components in the power system hamper the power quality, network efficiency and voltage regulation. The power quality issues like sag, swell, and voltage unbalance can be reduced by employing a dynamic voltage restorer (DVR). DVR provides the compensating power from a DC source to minimize the effect of sag, swell, and voltage unbalance. This article presents a power system with DVR using a photovoltaic system (PV) as a DC source instead of a conventional battery source. This article proposes a modified instantaneous power (PQ) control technique to generate the reference signal of load voltage to assure the DVR's superior performance. This modified technique uses an anti-aliasing filter to generate a reference signal. This proposed technique is tested under extreme power quality issues of 80% sag, 20% sag, 120% swell, 170% swell, and voltage unbalance. The DVR is modeled and simulated using MATLAB/Simulink. A comparison is made between the traditional and modified PQ methods from the obtained results. The analyzed results under severe power quality issues suggest that the proposed P-Q control technique is a preferable option for the DVR with PV as a DC power supply.</span>

An optimized synchronous approach to DC/DC droop backstepping control considering voltage compensation in DC microgrids

This paper addresses the impact of widely distributed power electronic loads and their constant power operations on the stability of DC microgrids. A backstepping controller, based on droop control, is proposed as a solution for mitigating the issues of constant power load in these grids. The unique feature of this controller is its independence from inter-device communication, which enhances the expandability and scalability of the DC microgrid. To tackle the challenge of power side converters needing a subsequent level DC/DC converter for voltage adjustment, a synchronous optimization method is introduced. This method, incorporating voltage compensation, keeps track of local output power during system transients. It identifies when the droop coefficient ratio deviates from proportionality, using this deviation as the initiation point for algorithm optimization. This approach modifies the local droop curve, enabling synchronous optimization. Before being optimized, the controller under heavy load conditions cannot meet the requirements of maintaining bus voltage and accurately allocating power simultaneously. However, after optimization, the system can maintain bus voltage while still ensuring accurate power allocation after disturbances. Moreover, the controller before optimization requires a secondary DC/DC converter to transfer electrical energy from the variable DC bus to the main bus. The optimized controller can effectively eliminate voltage offset and directly connect the DC/DC converter to the main bus, eliminating the cost problem caused by the secondary converter.

A novel ANFIS-controlled customized UPQC device for power quality enhancement

Power quality is crucial for the reliable and efficient operation of domestic and industrial loads. Nonlinear power electronic converter loads have increased in usage, which has led to a decline in both voltage and current quality. To overcome these power quality issues, a universal power quality compensator (UPQC) has been developed and integrated into the power distribution network. The UPQC comprises dual active power filters which are equipped with a DC-link capacitor. The voltage of the DC-link capacitor is controlled by a DC-link voltage controller. However, the conventional PI controller is not suitable for regulating voltage at a defined level due to inappropriate gain values. In this work, we propose an intelligent adaptive neuro-fuzzy inference system-based DC voltage controller for customized UPQC devices. The proposed control scheme aims to mitigate the existing power quality challenges by reducing the issues in classical controllers and incorporating intelligence knowledge with subjective decisions. Using the MATLAB/Simulink software tool, we have tested a customized UPQC device controlled by ANFIS for critical operation and performance. The simulation results are presented along with valid comparisons.

HARMONIC CLASSIFIER FOR EFFICIENCY INDUCTION MOTORS USING ANN

Modern electrical systems have a significant presence of electronic loads, which in turn produce negative impacts on distribution systems and loads, this has motivated their study to be increasingly prioritized, aiming to reduce their impacts from corrective actions. Harmonics are classified as positive, negative, and zero sequence, and their impacts on loads can vary according to the harmonic present. In the case of electric motors, negative sequence harmonics result in the greatest impacts. This work presents a classifier of existing harmonics in the input waveform of electric motors classes IE2, IE3 and IE4 using artificial neural networks (ANN), for that purpose, negative (2nd), positive (7th) and zero sequence harmonics (3rd) were applied separately and combined in the electric motors, the data was exported for a classification algorithm to identify existing harmonics. The results show how the algorithm presents good approximations of the present harmonics, mainly with those of positive and negative sequence.

A Novel DC Electronic Load Topology Incorporated with Model Predictive Control Approach

This paper presents a novel topology of a modified isolated single-ended-primary-inductance converter (SEPIC) with a model predictive control (MPC) approach applied to direct current (DC) electronic loads. The proposed converter uses an actual transformer rather than a coupled inductor for isolation between the source and the load. The transformer allows the proposed converter to operate at a higher switching frequency, ultimately reducing the passive components’ size. A low-power hardware prototype is developed and tested with a model predictive control algorithm under variable input voltages and load conditions. The performance of the proposed converter is demonstrated to be satisfactory under steady state, as well as sudden input voltage transients. The proposed converter utilizes a switched capacitor technique to generate alternating current in both windings of the transformer. As the coupled inductor is eliminated from the circuit, the problem of high voltage spikes occurring due to leakage inductances is also eliminated for the proposed converter. Therefore, the proposed converter can be used for isolated medium power applications. The experimental results show that the efficiency of the proposed converter reached 96%. The MPC allows this converter’s DC voltage level to remain stable even as the input voltage and output terminal load change. Lastly, this converter with an MPC approach can be applied to different DC electronic loads, improving DC power quality and DC electronic load life.

A Bicycle-Embedded Electromagnetic Harvester for Providing Energy to Low-Power Electronic Devices

Bicycles are rapidly gaining popularity as a sustainable mode of transportation around the world. Furthermore, the smart bicycle paradigm enables increased use through the Internet of Things applications (e.g., GPS tracking systems). This new paradigm introduces energy autonomy as a new challenge. The energy harvesting technology can capture the energy present in the cycling environment (e.g., kinetic or solar) to give this autonomy. The kinetic energy source is more stable and dense in this environment. There are several wheel kinetic harvesters on the market, ranging from low-complexity dynamos used to power bicycle lights to smart harvester systems that harvest kinetic energy while braking and cycling and store it for when it is needed to power sensors and other electronics loads. Perhaps the hub and the “bottle” dynamos are the most commercially successful systems because of their cost-effective design. Furthermore, the bottle generator is very inexpensive, yet it suffers from significant energy losses and is unreliable in wet weather due to mechanical friction and wheel slippage in the wheel/generator contact. This paper proposes a cost-effective bicycle harvester based on a novel kinetic-electromagnetic transducer. The proposed harvester allows for the generation and storage of harnessed kinetic energy to power low-power electronics loads when the user requires it (e.g., cell phone charging, lighting). The proposed harvester is made up of a power processing unit, a battery, and an optimized transducer based on a Halbach magnet array. An extensive full-wave electromagnetic simulation was used to evaluate the proposed transducer. Circuit simulation was also used to validate the proposed power unit. The proposed harvester generates a simulated output power of 1.17 W with a power processing unit efficiency of 45.6% under a constant bicycle velocity of 30 km/h.

Short-Circuit Protection Schemes for LVDC Microgrids Based on the Combination of Hybrid Circuit Breakers and Mechanical Breakers

In recent years, low-voltage direct current (LVDC) microgrids are becoming more attractive because they represent a solution to integrate renewable sources, storage, and electronic loads bringing some advantages in comparison with traditional AC grids. However, the protection of such a network involves many challenges, especially in the case of LVDC microgrids with more than one feeder and multiple energy sources. Indeed, the traditional protection breakers used for an AC grid cannot isolate the faults and protect the components of a DC grid, while the use of solid-state circuit breakers increases energy losses. This paper deals with the analysis and design of the protection schemes for LVDC microgrids through the combination of mechanical circuit breakers and hybrid circuit breakers. This solution has the advantage of energy loss reduction but introduces further issues due to the slow transition times of the mechanical circuit breakers. Thus, a completely decentralized control system capable of overcoming the fast fault-clearing time, cost-effectiveness, and selectivity issues is designed to protect from pole-to-pole faults. The proposed control strategy is compared with a centralized protection scheme available in the literature through numerical simulation. The two algorithms show similar performances, with a mean voltage dip duration of less than 30 ms and a maximum voltage dip duration of about 100 ms in the most severe fault condition, but the proposed solution is more reliable and flexible since it does not depend on the communication system.