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This paper presents a peer-to-peer community cost optimization approach based on a single-prosumer energy management system. Its objective is to optimize energy costs for prosumers in the community by enhancing the consumption efficiency. This study was conducted along two main axes. The first axis focuses on designing a digital twin for a residential community microgrid platform. This phase involves data collection, cleaning, exploration, and interpretation. Moreover, it includes replicating the functionality of the real platform and validating the results. The second axis involves the development of a novel approach that incorporates two distinct prosumer behaviors within the same community microgrid, while maintaining the concept of peer-to-peer energy trading. Prosumers without storage utilize their individual PV systems to fulfill their energy requirements and inject excess energy into a local microgrid. Meanwhile, a single prosumer with a storage system actively engages in energy exchange to maximize the community's profit. This is achieved by optimizing battery usage using a cost optimization solution. The proposed solution is validated using the developed digital twin. [ABSTRACT FROM AUTHOR]

Pumped storage units bring stability to the electrical power system, so they must remain connected to the grid even during grid faults. In this paper, the authors propose efficient and simple solutions for a doubly fed induction machine pumped storage (DFIMPS) system during grid faults. In case of balanced grid faults, a control reconfiguration strategy is introduced and a hardware solution is applied in the case of unbalanced grid faults. The reconfiguration strategy consists of a commutation between different control strategies; when a balanced grid voltage fault occurs during pumping mode, the control algorithm switches to the synchronization one but based on the new grid conditions. So the proposed reconfiguration method reduces the negative impacts of grid fault occurrence on the DFIMPS system by cancelling rotor and stator over-currents and decreasing the electromagnetic torque and stator power oscillations. Simulation results carried out on a 4 kW DFIMPS system illustrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

The integration of a large number of photovoltaic systems into the electricity grid presents significant technical challenges. To address the issue of excess power injection into the grid, various standards recommend curtailment of PV systems, which results in penalizing renewable energy. This paper proposes a solution to the problem without resorting to curtailment. The key innovation is to optimize the energy injected into the grid, achieving a delicate balance between benefits for prosumers and the grid operator, while also avoiding PV curtailment. The results obtained underscore substantial advantages for prosumers when contrasted with commercial solutions that resort to curtailing PV power, while ensuring the alignment of interests with network providers. The proposed energy management system is based on a multi-objective linear programming algorithm and aims to increase energy injection into the grid during peak regional demand while simultaneously considering the electricity price profile. The study utilizes digital twin technology to establish a dependable framework for validating proposed algorithms and comparing simulated results with experimental ones. By doing so, this process guarantees the accuracy of simulation results and allows for informed decision-making regarding the system under investigation. [ABSTRACT FROM AUTHOR]

Conventionally, standard proportional and integral (PI) controllers with constant PI gains are commonly used for the dc-link voltage control of single-phase grid-connected converters (GCCs). For such controllers, the selection of the PI gains will lead to a tradeoff between two control objectives: 1) the reduction of the dc-link voltage fluctuations caused by random swings of the active power drawn by the single-phase GCC; and 2) the reduction of the grid current harmonics mainly caused by the 2f oscillation of the active power in single-phase applications. To solve this tradeoff, this paper presents a systematic approach for the design of an adaptive PI controller for the dc-link voltage control of single-phase GCCs. The proposed design approach is simple and it provides a convenient method to properly determine the adaptive PI controller parameters. Representative simulation and experimental results are presented and discussed in order to show the effectiveness of the proposed dc-link voltage controller. [ABSTRACT FROM AUTHOR]

This paper presents a robust control strategy to improve dc-link voltage control performances for grid-connected converters (GcCs). The proposed control strategy is based on an adaptive proportional integral (PI) controller and is aimed to ensure fast transient response, low dc-link voltage fluctuations, low grid current total harmonic distortion, and good disturbance rejection after sudden changes of the active power drawn by the GcC. The proportional and integral gains of the considered adaptive PI controller are self-tuned so that they are well suited with regard to the operating point of the controlled system and/or its state. Several simulation and experimental results are presented to confirm and validate the effectiveness and feasibility of the proposed dc-link voltage control strategy. [ABSTRACT FROM PUBLISHER]

As any energy production system, photovoltaic (PV) installations have to be monitored to enhance system performances and to early detect failures for more reliability. There are several photovoltaic monitoring strategies based on the output of the plant and its nature. Monitoring can be performed locally on site or remotely. It measures production, focuses also on verification and follow-up of converter and communication devices' effective operation. Up to now, some faults diagnosis methods for PV components and systems have been developed. However, given the evolution of PV installations, more advanced monitoring techniques are continuously under investigation. In this paper, major photovoltaic system failures are addressed. Then techniques for photovoltaic monitoring proposed in recent literature are overviewed and analyzed to point out their differences, advantages and limits. [ABSTRACT FROM AUTHOR]

Grid-connected converters (GcCs) employ LCL filters instead of simple L filters in order to meet new grid codes and their on-going changes in the near future. Active damping methods, without power losses, are preferred to passive ones for solving the resonance problems of LCL-filter-based GcCs ( LCL-GcCs). However, large changes in the grid inductance (typically under weak grid conditions and in rural areas) may compromise the system stability. Moreover, the delay of digital controllers will change system phase-frequency characteristics and consequently will affect the system stability. In view of this, this paper proposes a systematic design procedure for the active damping of voltage-oriented PI control for LCL- GcCs. The procedure considers active damping methods based on capacitor current feedback and is aimed to ensure stable operation under severe grid inductance variations while taking into account the influence of digital control delay and LCL filter parameters changes on the system stability. Simulation and experimental results are presented and discussed in order to validate the proposed design procedure. [ABSTRACT FROM PUBLISHER]

This paper investigates the field-programmable gate array (FPGA) implementation of a fault-tolerant space vector-hysteresis current control (SV-HCC) for three-phase grid-connected converter. The proposed control ensures continuous operation despite of an open-circuit fault in one grid current measurement circuit (caused by defected cables, lines or connectors at the output of the current measurement circuit). It is based on hardware redundancy of current measurement circuits for fault detection and isolation. The faulty measured current is identified through the computation of residuals with well-defined thresholds. Thanks to the high computation capabilities of FPGAs, the implemented fault-tolerant SV-HCC is executed with a very high sampling frequency and very low execution time. As a consequence, the defined theoretical thresholds remain available for the experimental tests. Several experimental results, carried out on FPGA-based prototyping platform, are given in order to illustrate effectiveness and reliability of the proposed fault-tolerant SV-HCC. [ABSTRACT FROM AUTHOR]

In this paper, a doubly fed induction machine (DFIM) operating in motor mode and supplied by two voltage source inverters—in stator and rotor sides—is presented. The aim is to analyze the sensorless rotor position operation of a dual direct torque control (DDTC) of the DFIM. This paper presents a sensorless DDTC for a DFIM speed drive in order to guarantee the static and dynamic system performances. The sensorless DFIM operation provides an analytical redundancy in the case of mechanical sensor failure and ensures the service continuity of the drive. SABER simulation and experimental results illustrate the satisfactory behavior of the system with or without the use of the rotor position sensor. These confirm the preservation of system performances, particularly during the low-speed sensorless control operation. The proposed solution is particularly relevant due to its simplicity. [ABSTRACT FROM PUBLISHER]

This paper presents an easy and a robust sensor fault detection and isolation (FDI) and fault tolerant control (FTC) of a single phase PWM rectifier for electrical railway traction application. Catenary current sensor and dc link voltage sensor failures are considered. The FDI method is based on observers and residual generation. The different FDI algorithm steps allow a good detection and isolation of the sensor fault and identify the faulty sensor. The reconfiguration strategy consists of two steps with open loop control and closed loop control working. Simulation results are presented to illustrate the good performance of the FTC procedure. Experimental results are also presented to show the effectiveness of the proposed FDI and FTC algorithms and good performances of the rectifier after the reconfiguration. [ABSTRACT FROM AUTHOR]

This paper focuses on sensor fault detection and isolation (FDI) for electrical systems. A new, easy and fast FDI algorithm is proposed, keeping system performances unchanged under certain faulty sensor conditions when reconfigurations are available. The proposed FDI algorithm is derived from a parity space approach and is based on temporal redundancies. It is insensitive to parameter variations since no model knowledge is required. Also, it is available for a large class of electrical systems such as single- or three-phase power converters, dc or ac electrical drives, etc. Moreover, the residual threshold used for FDI is accurately defined and is suitable for the whole operating range. Simulations results are presented to illustrate the good functionality of theoretical developments. Numerous experimental results are also shown to validate the effectiveness of the proposed FDI algorithm and to highlight its advantages for the control of electrical systems. [ABSTRACT FROM AUTHOR]

This paper presents a grid-connection control strategy of doubly fed induction generator wind system based on the direct control of both a virtual torque and rotor flux of the generator. This control is achieved with no proportional-integral regulator and requires the measurement of only grid voltages, Eotor currents, and rotor position. The same switching table is used for grid synchronization and for running process. A field-programmable-gate-array-based design of the proposed control is developed and tested on a 4-kW experimental prototype. Experimental results are provided to show the effectiveness of the fast and soft grid-connection method developed. [ABSTRACT FROM AUTHOR]

This paper proposes an enhanced dynamic control strategy for a grid emulator. The proposed control switches between resonant and predictive controls in order to benefit from the advantages of both controls and to cope with their drawbacks. It ensures good dynamic performance in transient state and very low error in case of parametric or load variation during steady state. The most used control for grid emulator based on power converters is the one based on resonant controllers. Although this control is characterized by its robustness against parameters and load variation, it suffers from low performance in transient operation. The predictive control, which is characterized by its fast dynamic performance in transient state, can be used to overcome the resonant controllers limit. An exhaustive theoretical study reinforced by simulation and experimental results validate the capability, robustness and high performances of the proposed dynamic control strategy. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cell is a well-known technology that has shown high efficiency and performance as a power system compared to conventional sources such as internal combustion engines. Especially, open cathode proton exchange membrane is growing more popular thanks to its simple structure, low cost and low parasitic losses. However, the open cathode fuel cell performance is highly related to the operating temperature variation and the airflow rate which is adjusted through the fan voltage. In this regard, the present study investigates the thermal management of an open cathode proton exchange membrane fuel cell. The objectives are the stack performance improvement and the stack degradation prevention. Indeed, a safety and optimal operating zone governed by the load current, the stack temperature and the air stoichiometry, is designed. This optimal operating zone is defined based on the system thermal balance and the operating constraints. Hence, the proposed control strategy deals concurrently with the stack temperature regulation and the air stoichiometry adjustment to guarantee the goals achievement. The performance of the proposed control strategy is verified through experimental studies with different operating conditions and results prove its efficiency. To properly design an appropriate control strategy, a multiphysic fuel cell model is developed based on acausal approach by mean of Matlab/Simscape and experimentally validated. [ABSTRACT FROM AUTHOR]

This paper deals with a hybrid fault-tolerant converter topology. It is performed through the connection of a classical three-phase three-level neutral-point-clamped (3L-NPC) converter with a fourth three-level flying capacitor (3L-FC) leg. The 3L-FC leg actively balances the 3L-NPC neutral-point voltage. For normal operation mode, this paper proposes a mathematical design of the filter needed to connect these two different topologies. Experimentally, and thanks to the already existing decoupling capacitors of the 3L-NPC converter, this filter requires the addition of only one low size inductance. When one fault of the power switch of the 3L-NPC occurs, this paper proposes a hardware reconfiguration technique based on only two fuses and one thyristor per leg allows a safe postfault operation recovery. This is achieved thanks to a simple fault-detection method and a new technique that combines fault leg isolation and corresponding phase postfault connection to the neutral point. Also, a dedicated field-programmable gate array (FPGA)-based control of the reconfigured converter is synthetized to ensure power system availability under fault operation mode. The converter fault-tolerant capabilities are addressed through simulation results and original overall experimental validations of the fault detection and isolation and the postfault operation steps, carried out on a 15-kW prototype converter. [ABSTRACT FROM AUTHOR]

This paper investigates a hybrid multilevel converter for an induction machine drive. It is performed through the add of a 1-phase 3-levels FC-based leg to a classical 3-phases 3-levels NPC converter. The aim of the additional leg is to provide NPC legs with an active neutral point and, consequently, avoids the neutral point voltage unbalance issue. To ensure a balanced flying capacitor voltage and a constant neutral point, a strategy control of the FC leg is developed and an appropriate LC filter is proposed. The converter is simulated feeding a 1.5kW induction machine. Experimental results of the converter feeding a 1.5kW induction machine show the effectiveness of the developed control of FC leg and the proposed topology. [ABSTRACT FROM AUTHOR]

This paper deals with embedded real-time (RT) simulators applied in power electronic applications and implemented in low-cost field-programmable gate arrays. Indeed, such simulators' intellectual properties (IPs) are not only intended for hardware-in-the-loop (HIL) testing but also can be advantageously embedded within digital controllers to ensure functions such as observation, estimation, diagnostic, or health monitoring. Conversely, to the HIL case, the main challenge when designing such simulators' IPs is to cope with their complexity having in mind that, in the case of embedded systems, the available hardware resources are limited due to the cost. Furthermore, this challenge is strengthened by the need of very short simulation time steps that is typically the case when simulating power converters. By this way, this paper presents the design of an embedded RT simulator of a three-phase grid-connected voltage-source rectifier, based on the associated discrete circuit modeling approach. This IP is associated with the one of a three-phase $RL$ filter, and both are implemented within the rectifier controller to estimate the grid currents. The latter is injected in the controller when a fault is detected in the current sensors. The ability of this estimator to guarantee the service continuity in case of faults has been validated through HIL tests and experiments. [ABSTRACT FROM PUBLISHER]