The DFIG has been widely used in the wind power industry due to its technical advantages. However, current researches are being developed aiming at overcoming some of its drawbacks concerning reliability, efficiency and power quality. Since the wind farms are usually located at remote places, connected to weak grids, high reliability is required and some power quality issues deserve attention. This paper proposes a low-complexity, robust control of a DFIG driven by a direct matrix converter based on a model predictive rotor current control. The matrix converter is interesting due to the absence of the bulky and sensitive dc-link capacitors, leading to higher reliability. The predictive control is used to perform speed regulation. Moreover, this combination of converter and straightforward control is proven to be a robust technique that naturally compensates for stator current issues, which arises due to a low-power-quality grid voltage. Besides, a linear model of the proposed system is presented in order to be possible to use the linear-control-theory tools to execute the system control design. A processor-in-the-loop simulation is employed to validate the proposed control.

This paper proposes a technical methodology to decarbonize an isolated low-inertia system with the integration of a Renewable Energy Source (RES) and a Battery Energy Storage System (BESS). The proposal focuses on frequency support during contingencies, especially in terms of Synthetic Inertia (SI), for the Wind Power Plant (WPP), and Fast Frequency Response (FFR), for the BESS, allowing for a consistent decarbonization strategy throughout the operation. In particular, the BESS is analytically designed to provide the desired FFR for a contingency situation, allowing the Rate of Change of Frequency (RoCoF) of the system to be mitigated according to a design criterion that only requires the grid inertia and rated parameters, without relying on complex formulations or optimization methods. It is observed that the established design criterion is conservative and the enhancement in RoCoF values is above the expected. Furthermore, the synthetic inertia of the wind power plant can have an individual limited impact on the system’s RoCoF due to design and power ramping time, while the fast frequency response of the BESS has an additional impact due to the lack of power ramping requirements. Real-time simulation results validate the proposed methodology for an offshore industrial application within the Oil & Gas (O&G) industry.

This study analyzes the economic impacts of integrating floating offshore wind farms with a Floating Production, Storage and Offloading (FPSO) unit to reduce carbon dioxide emissions. The idea is to replace the use of natural gas for power supply with an offshore wind farm, considering the effects of carbon pricing. Results show that wind integration reduces emissions by 23% to 76%, depending on the installed capacity. However, higher wind capacity increases total system costs, initial investment, electricity and operational expenses. The Brazilian carbon credit market adversely impacts existing FPSO units as a result of the compulsory carbon trading costs necessary to mitigate their emissions. In contrast, wind-integrated scenarios benefited from carbon pricing, improving financial indicators such as payback period and Return on Investment. Wind shares of 30% and 70% yielded the best financial results for carbon prices between 10 and 50 United States Dollars per ton, with higher penalties further improving viability. These findings elucidate the significance of carbon pricing in mitigating emissions and enhancing the economic feasibility of offshore wind farms within the context of the Brazilian national FPSO decarbonization strategy.

This paper proposes a two-stage converter that can black start an isolated AC Microgrid with a Fuel Cell (FC) as the primary energy source. The first stage is connected to the FC and employs a Three-Leg Interleaved Boost DC/DC Converter (IBC), while the second is a Three-Phase Voltage Source Converter (VSC). The DC/DC stage utilizes a Cascade Voltage Control (CVC) to mitigate voltage fluctuations in the DC-link caused by the variability of the FC voltage. For the DC/AC stage, three distinct grid-forming (GFM) strategies are implemented with two of them with multi-loop cascaded structure and one with a single-loop structure. The power circuit of the system is simulated using the Real-Time Simulator (RTS) HIL 602+ from Typhoon-HIL, with the control strategies embedded on the Digital Signal Processor (DSP) TMS320F28379D - F28379D LaunchPad from Texas Instruments (TI). The performance of the cases are verified through CHIL simulations for a balanced and unbalanced inductive load steps. The results demonstrate that for both tests the GFM single loop structure presents smoother transients and shorter recovery times. Additionally, for the unbalanced loads, all the cases present similar results for the DC variables with more pronounced differences at the AC side.

This article addresses the study regarding the emergence of ferroresonance and selfexcitation phenomena in Subsea Power Systems - SPS, composed essentially of synchronous generators installed on a platform (Topside), a three-phase umbilical cable and the electrical loads, the latter constituted by induction machines located on the seabed and connected to the umbilical through a power transformer and power electronic converters. Such phenomena are conceptually stated and characterized in the scope of SPS and the simulations are carried out in the PSCAD/EMTDC software, in its parallel processing environment, to verify indications of the existence of problems in the base network of the subsea distribution system.