Direct Current (DC) grids are considered an attractive option for integrating high shares of renewable energy sources in the electrical distribution grid. Hence, in the future, Alternating Current (AC) and DC systems could be interconnected to form h...
The Special Issue on “Integration of High Voltage AC/DC Grids into Modern Power Systems” is published. A total of five qualified papers are published in this Special Issue. The topics of the papers are control, protection, operation, plan...
Due to the complex operation characteristics of AC/DC hybrid power grids, it is a great challenge to comprehensively evaluate their stability and formulate appropriate strengthening schemes for them. To address this challenge, the following studies a...
Hybrid AC/DC grids with High Voltage Direct Current (HVDC) systems enhance grid resilience and enable efficient long-distance power transfer, asynchronous network interconnection, and seamless integration of offshore renewable energy sources. However...
Power grids are evolving with the aim to guarantee sustainability and higher levels of power quality for universal access to electricity. More specifically, over the last two decades, power grids have been targeted for significant changes, including...
Integration of DC grids into AC networks will realize hybrid AC/DC grids, a new energetic paradigm which will become widespread in the future due to the increasing availability of DC-based generators, loads and storage systems. Furthermore, the huge...
In practical engineering, it has been observed that increasing local generators’ capacity in receiving-end power grids can lead the system to transition from voltage instability to power angle instability after a fault. This contradicts the typ...
For a new power system using high-penetration renewable energy, the traditional deterministic power flow analysis method cannot accurately represent the stochastic characteristics of each state variable. The aggregation of renewable energy with diffe...
With increasingly more renewable energy being integrated into the AC-DC hybrid grid, the grid shows more complex dynamic characteristics due to the mutual coupling of HVDC and renewable energy. To evaluate the renewable energy resources’ penetr...
Power grids are progressing, and the possibility of incorporating DC grids toward hybrid AC/DC grids is gaining increasing relevance, as several technologies available nowadays are operating natively in DC. This paper proposes a topology of a full-co...
This paper presents a new grid-forming strategy for hybrid AC/DC microgrids using bidirectional virtual inertia support designed to address weak grid conditions. The stability of hybrid AC/DC microgrids heavily relies on the AC mains frequency and th...
The growing incorporation of distributed energy resources (DER) in power distribution grids, although pivotal to the energy transition, increases operational variability and amplifies the exposure to disturbances that can compromise resilience and th...
In regions with concentrated load centers in China, the AC transmission network is dense, leading to challenges such as difficulties in power flow control and excessive short-circuit currents. The scale effect of AC grids is approaching saturation, m...
With the advancement in the “dual carbon” strategy and the integration of high proportions of renewable energy sources, AC/DC ultra-high-power grids are facing new security challenges such as commutation failure and multi-infeed coupling...
To evaluate the operation modes of AC/DC hybrid power grids, a comprehensive evaluation index system is established based on the principles of index system construction, with a focus on mode development personnel in practical engineering. This system...
The high rate of photovoltaic integration poses significant challenges in terms of violations of voltage limits in power grids. Additionally, the operational behavior of PV systems under fault conditions requires thorough investigation in receiving-e...
The design and optimization of power converters is a key factor in the growth and development of the power electronics field. However, the process of designing a power converter is not straightforward, and engineers often rely on experience and intui...
With the increasing integration of HVDC tie-lines, the regional power systems in both the energy-exporting area and the energy-importing area have been gradually evolving into “strong DC, weak AC” systems. In this paper, a multi-period tr...
AC/DC parallel transmission is a critical approach for large-scale centralized transmission. Existing assessments of power transfer capability in AC/DC corridors rarely incorporate comprehensive security and stability constraints, potentially leading...
One of the major challenges on large-scale Multi-Terminal High Voltage Direct Current (MT-HVDC) systems is the steady-state interaction of the hybrid AC/DC grids to achieve an accurate Power Flow (PF) solution. In PF control of MT-HVDC systems, diffe...
The Special Issue on “Integration of AC/DC Microgrids into Power Grids” is published. A total of six qualified papers are published in this Special Issue. The topics of the papers are the Optimal Power Flow (OPF), control, protection, and...
Electrical power grids are rapidly evolving into smart grids, with smart homes also making an important contribution to this. In fact, the well-known and emerging technologies of renewables, energy storage systems and electric mobility are each time...
Marine energy resources could be crucial in meeting the increased demand for clean electricity. To enable the use of marine energy resources, developing efficient and durable offshore electrical systems is vital. Currently, there are no large-scale c...
AC–DC power-flow calculation is the basis for studying HVDC systems. Since traditional iterative methods need many alternative iterations and have convergence problems, this paper proposes an alternating iterative power-flow algorithm for hybri...
With the wide application of distributed generation (DG) and the rapid development of alternating current/direct current (AC/DC) hybrid microgrids, the optimal planning of distributed generation connecting to AC/DC distribution networks/microgrids ha...
For the controllability of the transmission power of DC transmission channels, the optimal power distribution (OPD) of AC-DC parallel transmission channels is an effective measure for improving the economic operation of an AC-DC interconnected power...
Electrical power grids are changing with a focus on ensuring energy sustainability and enhanced power quality for all sectors. Over the last few decades, there has been a change from a centralized to a decentralized paradigm, which is the consequence...
This paper presents a robust nonlinear integrated controller to improve stability of hybrid AC/DC micro-grids under islanding mode. The proposed controller includes two independent controllers where each one is responsible to control one part of the...
AC/DC hybrid microgrids are becoming potentially more attractive due to the proliferation of renewable energy sources, such as photovoltaic generation, battery energy storage systems, and wind turbines. The collaboration of AC sub-microgrids and DC s...
In power systems, flow allocation (FA) methods enable to allocate the usage and costs of the transmission grid to each single market participant. Based on predefined assumptions, the power flow is split into isolated generator-specific or producer-sp...
The hybrid AC/DC microgrid is an independent and controllable energy system that connects various types of distributed power sources, energy storage, and loads. It offers advantages such as a high power quality, flexibility, and cost effectiveness. T...
Smart Transformers (STs) are being envisioned as a key element for the controllability of distribution networks in a future context of Renewable Energy Source (RES), Energy Storage System (ESS) and Electric Vehicle (EV) massification. Additionally, S...
Single-stage isolated and bidirectional (SSIB) AC–DC converters have a high potential for future solid-state transformers and smart battery chargers due to their reduced volume and high efficiency. However, there is a research gap for SSIB reac...
In a multi-fed DC environment, the UHV DC recipient grid faces significant challenges related to DC phase shift failure and voltage instability due to the high AC/DC coupling strength and low system inertia level. While the new large-capacity synchro...
In the transition to a sustainable energy system, the integration of electric vehicles into residential energy systems is an innovative solution for increasing energy resilience and optimizing electricity consumption. This article presents a bidirect...
An increased use of the high-voltage direct current (HVDC) technologies can have important effects on frequency performance and voltage stability of the receiving-end grid during normal operation as well as during blocking failure. The main reasons a...
This paper proposes an artificial neural network (ANN)-based energy management system (EMS) for controlling power in AC–DC hybrid distribution networks. The proposed ANN-based EMS selects an optimal operating mode by collecting data such as the power...
Over the past decade, there has been a great interest in the changeover from cars powered by gasoline to electric vehicles, both within the automotive industry and among customers. The electric vehicle–grid (V2G) technology is a noteworthy inno...
Energy harvesting technologies are becoming increasingly popular as potential sources of energy for Internet of Things (IoT) devices. Magnetic field energy harvesting (MFEH) from current-carrying components, such as power cables, represents a particu...
This paper evaluates, for a 2030 scenario, the impact on onshore power systems in terms of the variability of the power generated by 81 GW of offshore wind farms installed in the North Sea. Meso-scale reanalysis data are used as input for computing t...
AC/DC converters, controlled by pulse width modulation (PWM) and used as power factor correction (PFC), is considered one of the main contributors to emissions in the range 2 kHz–150 kHz, recently known as the supraharmonic (SH) range. This stu...
Energy Recovery Battery Testing Systems (ERBTS) plays an important role in battery manufacture. The conventional ERBTS configuration contains a fundamental transformer, and a bidirectional Direct Current (DC)–DC and Alternating Current (AC)–DC conve...
The presence of DC grids in distribution networks is being increased nowadays and is expected to be quite relevant in a near future, due to several advantages compared to traditional AC systems. Regardless of this, Power Quality in DC grids (DC PQ) (...
Due to the development and deployment of renewable DC power sources and their inherent advantages for DC loads in applications, the DC nano-grid has attracted more and more research attentions; especially the topologies of AC/DC converters are increa...
In order to reduce the impact of the randomness and volatility of renewable energy on the economic operation of AC/DC hybrid microgrids, a multi-time-scale rolling optimization strategy is proposed for the grid-connected AC/DC hybrid microgrids. It c...
Hybrid AC/DC transmission expansion planning must balance investment cost, supply reliability and AC/DC stability, which challenges conventional mathematical programming and heuristic methods. This paper proposes a multi-objective planning framework...
In this paper, a centralized control strategy for the efficient power management of power converters composing a hybrid AC/DC microgrid is explained. The study is focused on the converters connected to the DC bus. The proposed power management algori...
This paper explores the strategic planning required for a zero-carbon-emission AC/DC microgrid, which integrates renewable energy sources and electric vehicles (EVs) within its framework. It considers the rapidly growing adoption of EVs and the adven...
With the maturation of ultra-high-voltage direct current (UHVDC) technology, DC grids are taking on a more critical role in power systems. However, their impact on AC grids has become more pronounced, particularly in terms of frequency, short-circuit...
This paper presents a groundbreaking control strategy for a bidirectional battery charger that allows power to be injected into the smart grid while simultaneously compensating for the grid’s reactive power using an electric vehicle battery. An...
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