This dataset is about the experimental results obtained and published in the article "A Control Scheme to Suppress Circulating Currents in Parallel-Connected Three-Phase Inverters": Liberos, M.; Gonzalez-Medina, R.; Patrao, I.; Garcera , G.; Figueres, E. Electronics 2022, 11, 3720.
DOI: 10.3390/electronics11223720

The parallel operation of inverters has many benefits, such as modularity and redundancy. However, the parallel connection of inverters produces circulating currents that may result in malfunctions of the system. In this work, a control technique for the elimination of the low-frequency components of the circulating currents in grid-connected inverters is presented. The proposed control structure contains n - 1 zero-sequence control loops, with n being the number of inverters connected in parallel. Simulation and experimental results have been carried out on a prototype composed of two 5 kW inverters connected in parallel. The results have been obtained by considering the following mismatches between both inverters: inductance values of the grid filters, unbalance of the delivered power, and the use of different modulation techniques.

A theoretical analysis of a three-phase grid-connected B4 photovoltaic inverter was carried out, including modeling, control design, and stability assessment of the current and voltage control loops.
The influence of photovoltaic voltage and grid inductance variations was analyzed through a parametric stability study.
Finally, simulation-based evaluations were performed under ideal and distorted grid conditions to assess harmonic behavior, DC bus voltage ripple, and overall system performance., Funded by the Ministerio de Ciencia e Innovacion of Spain and the European Regional Development Fund (ERDF) under Grant PID2021-122835OB-C22

[EN] This dataset comprises the experimental measurements acquired using a versatile 7 kW inverter prototype configurable as B4 and B6, tested under grid-connected operation in a laboratory microgrid setup. The data support the comparative evaluation of both topologies in terms of efficiency, line-current total harmonic distortion (THD), and current unbalance, among other performance indicators reported in the associated publication.
Associated publication: Torán, E.; Liberos, M.; Patrao, I.; González-Medina, R.; Garcerá, G.; Figueres, E. Performance Evaluation of the B4 Topology for Implementing Grid-Connected Inverters in Microgrids. Electronics 2024, 13(9), 1755. DOI: 10.3390/electronics13091755., Project REMOTEWEAK, Mejora de la calidad de potencia en sistemas de potencia remotos con conexión a red débil y elevada penetración de convertidores electrónicos de potencia, funded by the Spanish Ministerio de Ciencia e Innovación and the European Regional Development Fund (ERDF) under Grant PID2021-122835OB-C22.

This dataset is about the experimental results obtained and published in the article "Experimental Study of the Parameter Mismatch Effects on the Low Frequency Circulating Currents of Parallel Three Phase Inverters":Liberos, M.; González-Medina, R.; Patrao, I.; Torán, E.; Garcerá, G.; Figueres, E. Eng 2023, 4, 1356-1376.
DOI: 10.3390/eng4020079

When converters are connected in parallel, a system with some benefits, including modularity and redundancy, is obtained. However, in these circumstances, circulating currents can appear that produce some adverse effects. In this work, a study of the low-frequency circulating currents that appear in three-phase inverters connected in parallel is performed. The study is focused on the effects produced by the parameter mismatch, namely inductance mismatches, power imbalance, and the use of different pulse with modulation (PWM) techniques. The nature of the circulating current produced by each of these factors were analyzed separately. Both simulation and experimental results are shown, which were obtained using a three-phase 10-kW prototype composed of two 5-kW inverters connected in parallel

Active Power Filters (APF) for reducing current harmonic distortion have been widely used in both grids and microgrids. This work proposes a topology for an APF consisting of two Voltage Source Inverters (VSIs) connected in parallel to the same DC-link, which saves space and reduces cost compared to independent APFs. One inverter operates at a low switching frequency and compensates for low-order harmonics. The second inverter operates at a high switching frequency to target high-frequency harmonics. As the high-frequency inverter handles only around 25% of the total RMS current managed by the overall APF, switching losses are significantly reduced. However, connecting inverters in parallel produces circulating currents that can have an adverse effect on the system. In this work, circulating currents are cancelled by controlling the zero-sequence component of the currents in the two inverters.

A theoretical analysis of a three-phase grid-connected B4 photovoltaic inverter was carried out, including modeling, control design, and stability assessment of the current and voltage control loops.
The influence of photovoltaic voltage and grid inductance variations was analyzed through a parametric stability study.
Finally, simulation-based evaluations were performed under ideal and distorted grid conditions to assess harmonic behavior, DC bus voltage ripple, and overall system performance., Funded by the Ministerio de Ciencia e Innovacion of Spain and the European Regional Development Fund (ERDF) under Grant RTI2018-100732-B-C21-AR.
Funded by the Ministerio de Ciencia e Innovacion of Spain and the European Regional Development Fund (ERDF) under Grant PID2021-122835OB-C22.

This dataset is about the experimental results obtained and published in the article by the authors I. Patrao, E. Tor n, R. Gonz lez-Medina, M. Liberos, E. Figueres and G. Garcer , "DC-Bus Signaling Control Laws for the Operation of DC-Microgrids With Renewable Power Sources," in IEEE Journal of Emerging and Selected Topics in Industrial Electronics, vol. 5, no. 3, pp. 1120-1131, July 2024, doi: 10.1109/JESTIE.2023.3345797.

The behaviour of the different agents in a microgrid is managed by using the voltage at each node of the microgrid as the DBS signal. The technique proposed in this paper uses an improved DBS technique to coordinate interlinking converters, photovoltaic generators, Energy Storage Systems and loads in a microgrid. The DBS technique proposed in this paper is adapted to integrate renewable power sources in the microgrid. The DBS-controlled Energy Storage Systems (ESS) will store the surplus energy if the generated power exceeds consumption. In the case of fully charged ESS, the renewable generators will limit their output power to those demanded by the loads. The proposed control laws have been tested in an experimental microgrid.

Having two or more interlinking converters connected in parallel in hybrid microgrids with AC and DC buses has some benefits, like modularity, flexibility, and redundancy. However, the parallelization of the inverters leads to circulating currents that can cause system malfunctions. This work uses a method for suppressing low-frequency circulating currents in interlinking converters by controlling the zero-sequence component of the phase currents, showing that the control structure is valid for interlinking converters. The proposed control scheme has been applied to two parallel interlinking inverters of 5 kW and 2.5 kW, respectively. The interlinking inverters are connected to the grid, and they control the voltage in the DC bus of the hybrid microgrid. To validate the concept, simulation and experimental results are shown.

[EN] Experimental results about the control structure and the dynamic modelling of the NPC+GCC transformerless inverter used in single phase Photovoltaic power systems. The high capacitance to ground of the photovoltaic generator leads to undesirable high-leakage currents. Using half-bridge topologies dramatically reduces the leakage to ground, and using a multilevel half-bridge inverters improves the output quality compared with classical inverters. The neutral point clamped + generation control circuit (NPC + GCC) topology is a multilevel single-phase transformerless inverter capable of tracking the maximum power point of two photovoltaic sources at the same time. The Pulse-Width Modulated (PWM) switch model in continuous conduction mode (CCM) has been used to obtain the small-signal model of the two switching converters that make up the inverter. The resulting dynamic model is used to quantify the stability margins of both converters' current and voltage loops., Project REMOTEWEAK, Mejora de la calidad de potencia en sistemas de potencia remotos con conexión a red débil y elevada penetración de convertidores electrónicos de potencia. Funded by the Ministerio de Ciencia e Innovación of Spain and the European Regional Development Fund (ERDF) under Grant PID2021-122835OB-C22