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High-voltage direct current (HVDC) transmission systems using Voltage-Source Converters (VSC) are widely recognized as offering significant potential for long distance high power delivery, particularly for offshore wind farm connections. One of the barriers for the development of multi-terminal HVDC systems is the lack of technologies which enable...
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This paper focuses on the transmission system options for connection of offshore wind farms and investigates the advantages and disadvantages of proposed concepts in order to draw a conclusion regarding their suitability for connection in the electricity system. Then, the most appropriate solution is implemented in Matlab/Simulink to show its benef...
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... This temperature rise causes the r-SFCL to transition to a resistive state, introducing a nonzero impedance to the circuit and effectively limiting the fault current. The entire transition process occurs within milliseconds, ensuring the continued safe operation of circuit breakers and switchgear [31]. Since thermoelectric transition is the main process responsible for an r-SFCL's performance, it is crucial to accurately model the thermoelectric behavior of the r-SFCL in this study. ...
The increasing penetration of renewable energy sources (RESs) into electrical networks offers several interesting opportunities and challenges. One such opportunity is the utilization of DC transmission lines, which can enhance the efficiency and reliability of power transmission. However, DC transmission lines face a challenge in dealing with fault currents due to their high magnitudes and the absence of zero crossing points, characteristics that make it difficult for DC circuit breakers (CBs) to clear faults. Resistive superconducting fault current limiters (r-SFCLs) effectively minimize high magnitude fault currents, allowing DC CBs to operate safely during fault scenarios. The self-triggering feature and fast fault current limitation ability of r-SFCLs also make them particularly suitable for protecting against high DC fault currents. Several studies demonstrated the performance of r-SFCLs with one type of stabilizer layer, most commonly using either copper (Cu) or stainless steel (SS). This paper investigates and compares the performance of an r-SFCL with the two different stabilizer layers, with one case using copper and the other using stainless steel. A thermoelectric r-SFCL model incorporating all composed layers has been developed in Simulink/MATLAB® to investigate the performance of the r-SFCLs with the two different stabilizer layers. The r-SFCLs have been evaluated using different fault scenarios applied to the DC transmission lines of a solar farm. In this model, all r-SFCL layers, excluding the stabilizer layer but including the superconducting, silver, and substrate layers, have been fixed to show the impact of the stabilizer layer materials on the r-SFCL’s performance. This paper illustrates the fault current limiting capability of the r-SFCL, its effect on voltage behavior, its operating temperature, and its sensitivity to the fault location with the two different stabilizer layers. To simulate a range of fault levels and assess the limitation capability of the r-SFCLs, three distinct fault locations have been considered: one located 5 km away from the solar farm, another 15 km away, and a third 25 km away.
... and hence C α N > C α S and extra-ordering arises which causes the rejection of the extra heat and this may have motivating practical applications [121]. In fact, the laws obtained for ΔC α are practical in the study of low-temperature superconductors which are subject to residual contributions when we notice an upturn in several heavy-fermion paramagnets such as UTe 2 , [122][123][124][125]. Besides, Eq. (5) can be used to model specific heat anomaly at the superconducting transition phase [126][127][128][129][130][131]. ...
... This reduces fault damage and aids the protection system so DC circuit breakers can be securely operated [19]. SFCLs support the DC circuit breakers to operate at lower fault current levels, thus improving their operational durability [42,43]. The stabilizer layer strongly impacts the SFCL's performance during fault scenarios [44]. ...
... In the event of an electrical fault, an SFCL can reduce the fault current within milliseconds using an internal mechanism, allowing the circuit breakers and switchgear to continue functioning safely [43]. Resistive SFCLs (r-SFCLs) and inductive SFCLs (i-SFCLs) are the two main types of SFCLs. ...
Utilizing renewable energy sources (RESs) to their full potential provides an opportunity for lowering carbon emissions and reaching a state of carbon neutrality. DC transmission lines have considerable potential for the integration of RESs. However, faults in DC transmission lines are challenging due to the lack of zero-crossing, large fault current magnitudes and a short rise time. This research proposes using a superconducting fault current limiter (SFCL) for effective current limitation in PV-based DC systems. To properly design an SFCL, the present work investigates the effect of copper stabilizer thickness on SFCL performance by using an accurate multilayer thermoelectric model. In the MATLAB/Simulink platform, the SFCL has been modeled and tested using different copper stabilizer thicknesses to demonstrate the effectiveness of the SFCL model in limiting the fault current and the impact of the copper stabilizer thickness on the SFCL’s performance. In total, four different thicknesses of the copper stabilizer were considered, ranging from 10 μm to 80 μm. The current limitation and voltage profile for each thickness were evaluated and compared with that without an SFCL. The developed resistance and temperature profiles were obtained for various thicknesses to clarify the mechanisms behind the stabilizer-thickness impact. An SFCL with an 80 µm copper stabilizer can reduce the fault current to 5.48 kA, representing 71.16% of the prospective current. In contrast, the fault current was reduced to 27.4% of the prospective current (2.11 kA) when using a 10 µm copper stabilizer.
... The main objective of such mechanical breakers is to build up arc voltages higher than the system voltage to force the fault current to zero. Higher arc voltages can be produced by connecting several contacts in series or by using arc splitter plates [6]. However, the use of a pure mechanical breaker is limited to low voltage systems because for high fault currents and high system voltages, building up high arc voltages, absorbing the energy stored in the system inductance, and dissipating the generated heat are big challenges. ...
One of the key-enabling technologies of low inductive low voltage direct current (DC) systems is a breaker that can interrupt fault currents in less than a millisecond
to avoid large fault currents. In this paper, the interruption capability of a hybrid breaker’s solid-state branch is analyzed with and without a resistive-capacitive-diode (RCD) snubber. Simulation models were used in tandem with experiments
to study the peak insulated gate bipolar transistor (IGBT) voltage and junction temperature at 3800 A. It has been shown that, in the absence of a snubber, the switching energy losses increased by 160 %. It has also been shown that at 3800 A, the switching losses amount to 30 % of the total losses. Hence this has little contribution to the IGBT junction temperature rise. Consequently, omitting an RCD snubber results in significant size and cost reductions at the expense of a 20 % increased peak voltage during the turn-off process. This however can be mitigated by alternative cost-effective methods such as decreasing the stray inductance or switchable gate resistors.
... Due to the grid connection of large-capacity renewable energies, various distributed generation systems and HVDC transmission lines, the global research direction is to develop Multi Terminal DC (MTDC) grids. Because MTDC grid improves stability and reliability of the system and reduces asset cost [4]. On the other hand, owing to the lack of zero-crossing in HVDC systems, the fault is a significant obstacle to implementing this technology. ...
... The HFCL proposed in [4] is based on a new theory, i.e., the push-pull principle. Although the authors mentioned that the fault current is limited by 23 % in a short time (between 1.002 to 1.06 sec), the use of IGBT switches in the normal path and many half-bridge submodules based on IGBTs in the limiting path increase the switching loss and associated costs. ...
... There are many different solutions of limiters. The most popular are resistive-type limiters, inductive-type limiters and limiters with a DC biased magnetic field [122]. SFCLs are a group of superconducting devices with the biggest potential for industrial applications. ...
The main aim of this review is to present the current state of the research and applications of superconductivity and plasma technologies in the field of energy and environmental protection. An additional goal is to attract the attention of specialists, university students and readers interested in the state of energy and the natural environment and in how to protect them and ensure their sustainable development. Modern energy systems and the natural environment do not develop in a sustainable manner, thus providing future generations with access to energy that is generated from renewable sources and that does not degrade the natural environment. Most of the energy technologies used today are based on non-renewable sources. Power contained in fuel is irretrievably lost, and the quality of the energy is lowered. It is accompanied by the emissions of fossil fuel combustion products into the atmosphere, which pollutes the natural environment. Environmental problems, such as the production of gaseous and solid pollutants and their emission into the atmosphere, climate change, ozone depletion and acid rains, are discussed. For the problem of air pollution, the effects of combustion products in the form of carbon oxides, sulfur and nitrogen compounds are analyzed. The plasma and superconductivity phenomena, as well as their most important parameters, properties and classifications, are reviewed. In the case of atmospheric pressure plasma generation, basic information about technological gas composition, pressure, discharge type, electromagnetic field specification, electrode geometry, voltage supply systems, etc., are presented. For the phenomenon of superconductivity, attention is mainly paid to the interdependencies between Tc, magnetic flux density Bc and current density Jc parameters. Plasma technologies and superconductivity can offer innovative and energy-saving solutions for power engineering and environmental problems through decreasing the effects of energy production, conversion and distribution for the environment and by reductions in power losses and counteracting energy quality degradation. This paper presents an overview of the application of technologies using plasma and superconductivity phenomena in power engineering and in environmental protection processes. This review of plasma technologies, related to reductions in greenhouse gas emissions and the transformation and valorization of industrial waste for applications in energy and environmental engineering, is carried out. In particular, the most plasma-based approaches for carbon oxides, sulfur and nitrogen compounds removal are discussed. The most common plasma reactors used in fuel reforming technologies, such as dielectric barrier discharge, microwave discharge and gliding-arc discharge, are described. The advantages of solid waste treatment using plasma arc techniques are introduced. Applications of superconductors for energy generation, conversion and transmission can be divided into two main groups with respect to the conducted current (DC and AC) and into three groups with respect to the employed property (zero resistivity, ideal magnetism/flux trapping and quench transition). Among the superconductivity applications of electrical machines, devices for improving energy quality and storage and high field generation are described. An example that combines the phenomena of hot plasma and superconductivity is thermonuclear fusion. It is a hope for solving the world’s energy problems and for creating a virtually inexhaustible, sustainable and waste-free source of energy for many future generations.
... Various types of FCLs exist, but to keep things simple and emphasise their importance, we bifurcate them in two broad categories ( Figure 2). First broad category comprise superconducting FCLs (SFCLs) (Lee et al. 2014a;Jo and Joo 2015;Pei, Smith, and Barnes 2015;Xiang et al. 2020) and other is nonsuperconducting FCLs (NSFCLs) (Hagh and Abapour 2009;Hagh, Jafari, and Naderi 2010;Kopylov et al. 2012;Hossain 2017;Rashid and Ali 2017;Sahoo, Tripathi, and Chatterjee 2019). However, few other types of FCLs do exist, such as hybrid FCLs, solidstate FCLs (SSFCLs), and other technologies (Safaei et al. 2020). ...
The energy hunger society drives for more electrical power consumption to raise the
human conveniences has put tremendous pressure on the existing power system (PS)
to function uninterruptedly. The continuous addition of non-linear loads brings a heavy
inrush of fault current leading to transient instability in PS. To protect the PS and its
precious elements, fault current limiters (FCLs) are generally installed with a view to
limit those FCs before inviting severe damage and also quickly restore the PS to their
original state. Furthermore, since faults are inevitable, efforts can only be made to
minimize those damages by improving the FCLs. Herein, a brief history of FCLs,
concepts, working principles, developmental stages, and experimental data, along with
theoretical predictions, have been systematically presented. Finally, this article
elaborates on the current challenges of FCLs, future perspectives, and, most
importantly, their market potentials.
... The transition to renewables will gradually transform the grid into a meshed-HVDC grid due to the higher efficiency of HVDC transmission from remote renewable energy generation sites [3,4]. With such changes, HTS applications are becoming increasingly relevant: HTS cables for efficient power transmission, superconducting fault current limiters (SFCLs) for HVDC grid protection and superconducting compact generators for wind turbines, to name a few [5][6][7]. However, to tap into the full potential of HTS applications, the main problem of hotspots needs to be addressed. ...
A Mach-Zehnder Interferometer (MZI) based optical fibre sensing technique, developed and patented by EPFL, is an efficient and economical way to detect hotspots in High Temperature Superconductor (HTS) applications. Due to the MZI sensitivity being a composite of strain sensitive and temperature sensitive contributions, the MZI gives an instantaneous response to a quench (within 10 ms), because of the quick strain transfer to the optical fibre. However, the MZI output signal also manifests the environmental noise caused by mechanical vibrations, bubbling in the cryostat and temperature variations, along with the response to the quench. This presents the problems of false alarms and indiscernible response to a quench. Discrete wavelet transform (DWT) has been proven to be a useful tool for feature extraction in different fields requiring signal categorization and hence holds the potential to enable quench recognition in the MZI output. This paper proposes an effective approach of performing DWT based feature extraction on experimental data and subsequently using the extracted features for the MZI response classification using two machine learning based classification techniques: k-nearest neighbours (KNN) and Artificial Neural Network (ANN). For this manuscript, experiments were performed using MZI for quench detection in an HTS tape. Feature extraction was then implemented on these experimental measurements using discrete wavelet coefficients extracted at different decomposition levels from the MZI output; these features were then used to train the KNN and ANN models for identifying quench in the MZI signal. This method could be a valuable supplement to the MZI technique by enabling the development of a real time application that can process the MZI output data as well as eliminate the occurrences of false alarms; thereby facilitating reliable quench detection. With this development, the MZI technique would become an even more attractive solution for the health monitoring of HTS applications.
... Voltage source converter-based high-voltage direct current (VSC-HVDC) transmission technology can be used for high capacity and efficient power transmission in renewable energy generation systems [1,2]. However, the highvoltage DC circuit breaker with large cut off capacity is rather expensive, which is one of the important factors for restricting the wide application of VSC-HVDC transmission technology [3]. ...
... Tao Ma taom@bjtu.edu.cn 1 Guangdong Power Grid, Guangzhou, China 2 School of Electrical Engineering, Beijing Jiaotong University, Beijing, China the fault current, and the impedance of the SFCL also affects the fault current value as well. Therefore, SFCL needs to be designed according to the fault current characteristics of the power grid [4][5][6][7][8]. ...
When short-circuit fault occurs in a voltage source converter–based high-voltage direct current (VSC-HVDC) transmission system, the fault current curve is much more complex than conventional AC power grid. The high-voltage DC circuit breaker with large cut-off capacity is rather expensive; thus, some current limiting methods are proposed to limit the fault current. The superconducting fault current limiter (SFCL) is one of the promising devices for both AC and DC short-circuit current limiting application. The optimization criterion for SFCL applied in VSC-HVDC system is presented, and a four terminal VSC-HVDC system is adopted as an example. The short-circuit fault could be divided into condenser discharge and AC system feeding process, and the fault current curve is related to the time-varying RLC parameters of the grid. The thermal and resistance characteristics of the SFCL are analyzed, and the optimization method of the current limiting impedance and thermal characteristics of the SFCL is developed based on the time-varying fault current. Finally, the design of a 160-kV SFCL was completed based on the proposed method.
... Because this makes the converter's internal components susceptible to damage, these components must be protected from DC fault currents. Unlike AC current, there is no zero-crossing point in DC, making it difficult to interrupt a large short-circuit fault current with a conventional DC circuit breaker (DCCB) [1]. Manuscript Therefore, a current limiting device is required to limit the DC fault current to a relatively low level. ...
Several recent studies have proposed a conceptual design of a saturated iron-core superconducting fault current limiter (SI-SFCL) for DC power systems, but experimental studies to verify its operating characteristics and performance have not yet been conducted. In this paper, a laboratory-scale SI-SFCL was designed and tested to operate in a 500 V, 50 A DC power system. First, the detailed configuration, specifications, and hardware manufacturing contents of the SI-SFCL were presented, and then an experimental circuit was developed and installed for the performance test of the SI-SFCL in normal operation and failure conditions. A 3D finite element method model was constructed to compare the simulation results and experimental results for the operating function of the SI-SFCL. Without the SI-SFCL, the maximum fault current level was 500 A, as a result, the SI-SFCL has a large current limit function, which can reduce the magnitude of the fault current up to the design target value of 73.6%. The results obtained in this study can be effectively applied to large-scale SI-SFCL development studies for HVDC power systems.
