Interconnect Lines Research Articles

Investigating the long-term benefits of EU Electricity Highways: The case of the Green Aegean Interconnector

This paper investigates the potential long-term benefits that could be arisen by the construction and operation of the envisioned “Green Aegean Interconnector”. This will be a pioneering 9-GW direct interconnection line connecting Greece with Germany to facilitate the transfer of massive amounts of RES generation from South-East to Central-North Europe. The ultimate goal of this analysis is to estimate the total electricity supply cost to be undertaken by the end-consumers in Greece with and without the said interconnector along with the cost/benefit of the Greek national economy associated with the foreseen cross-border electricity exchange. Detailed simulations of the Greek electricity market using a specialized electricity market simulation software on the basis of the main provisions of the revised Greek National Energy and Climate Plan are performed under realistic market evolution scenarios for a future 30-year study horizon (2026-2055). Simulation results and the associated cost-benefit analysis indicate that such a project would enable the operation of additional RES projects in Greece. This would, in turn, decrease the overall Greek end-consumers’ electricity cost and create a significant surplus for the Greek economy through the increased exporting activity, whereas at EU-level it would assist towards further achieving the European energy market integration.

Stress-induced warpage estimation of advanced semiconductor copper interconnect processes

The growth of the semiconductor industry is driven by the demand for electronic products and high transistor density. However, complex manufacturing processes generate residual stress and result in wafer warpage. Therefore, mastering wafer warpage has become a crucial challenge. This study proposes a process-oriented simulation methodology with simulation-based equivalent material method to overcome the difficulty of finite element modeling and the substantial amount of computation time. Three different methodologies, including volume percentage, representative volume element, and Timoshenko bi-material approach, are discussed due to the estimation of residual stress for equivalent material. In addition, each methodology is validated through process-oriented simulations and comparison with measurement data. The Timoshenko bi-material approach is efficient in predicting warpage in the back end of line (BEOL) interconnects and provides a comprehensive understanding of the warpage variation that occurs during different stages of BEOL.

Research on priority scheduling strategy for smoothing power fluctuations of microgrid tie‐lines based on PER‐DDPG algorithm

AbstractThe variability of renewable energy within microgrids (MGs) necessitates the smoothing of power fluctuations through the effective scheduling of internal power equipment. Otherwise, significant power variations on the tie‐line connecting the MG to the main power grid could occur. This study introduces an innovative scheduling strategy that utilizes a data‐driven approach, employing a deep reinforcement learning algorithm to achieve this smoothing effect. The strategy prioritizes the scheduling of MG's internal power devices, taking into account the stochastic charging patterns of electric vehicles. The scheduling optimization model is initially described as a Markov decision process with the goal of minimizing power fluctuations on the interconnection lines and operational costs of the MG. Subsequently, after preprocessing the historical operational data of the MG, an enhanced scheduling strategy is developed through a neural network learning process. Finally, the results from four scheduling scenarios demonstrate the significant impact of the proposed strategy. Comparisons of reward curves before and after data preprocessing underscore its importance. In contrast to optimization results from deep deterministic policy gradient, soft actor‐critic, and particle swarm optimization algorithms, the superiority of the deep deterministic policy gradient algorithm with the addition of a priority experience replay mechanism is highlighted.

Distributed photovoltaic supportability consumption method considering energy storage configuration mode and random events

In order to improve the control capability of distributed photovoltaic support, a distributed photovoltaic support consumption method based on energy storage configuration mode and random events is proposed. A networked and constrained parameter analysis model for distributed photovoltaic power supply control was constructed. Based on the direct flexible mode of optical storage, an AC/DC voltage level control model for distributed solar power supply control was constructed. In the operation mode of DC hybrid distribution network, the demand response tracking identification method was used to analyze the uncertain characteristic parameters of distributed solar power supply load, and combined with the planned energy storage capacity parameters, the distributed solar power supply load and photovoltaic output were estimated. By configuring the optimal energy storage capacity, adjusting the power distribution of the microgrid, and integrating the analysis of uncertain factors and random events in the energy storage configuration mode, the design of distributed photovoltaic support consumption has been achieved. The experimental results show that the distributed photovoltaic absorption control using this method has lower load requirements, can effectively reduce the exchange power of the interconnection line, and improve the configuration scale, system reliability, and economy of the photovoltaic energy storage system.

Optimal configuration of hydrogen storage capacity of hybrid microgrid considering peak regulation and frequency modulation requirements

This study proposes an innovative hydrogen storage capacity optimization configuration method that considers multiple demand factors, addressing the issue that traditional methods for optimizing hydrogen storage capacity in hybrid microgrids cannot simultaneously balance economic efficiency and grid connection quality. This method breaks through the traditional optimization framework and adopts a double-layer optimization model, combining the peak shaving operation cost of the hybrid microgrid with the interactive power deviation and power fluctuation penalty terms of the interconnection line during the frequency regulation stage, achieving dual optimization of economy and grid connection quality. Through precise mathematical modeling and efficient optimization algorithms, we have successfully obtained the minimum operating cost corresponding to the minimum power fluctuation, the minimum interconnection line interactive power deviation penalty term, and the optimal hydrogen storage capacity configuration scheme. Identify two typical days through cluster analysis. Option 1 (considering peak shaving, frequency regulation, and hydrogen electrolysis) has the lowest net load and a total operating cost of 3.0331 million yuan, which is better than Option 2 (3.0973 million yuan) and Option 3 (5.0398 million yuan). This plan effectively reduces wind and solar power waste, shortens the operating time of thermal power units, and demonstrates the rationality and economy of optimizing hydrogen storage capacity configuration.

Investigating the Impact of Interconnection Line Power Losses on Unit Commitment of Grid-Connected Microgrids

Investigating the Impact of Interconnection Line Power Losses on Unit Commitment of Grid-Connected Microgrids

Leveraging Pumped Storage Power Plants for Innovative Stability Enhancement of Weakly Interconnected Power Systems

The hybrid AC/DC grid, based on a significant share of renewable energy sources, is gradually becoming an essential aspect of the modern energy system. The integration of intermittent renewable generators into contemporary energy systems is accompanied by the decommissioning of power plants containing synchronous generators. Consequently, this leads to a reduction in system inertia and an increase in the risk of stability disruption. The abrupt disconnection of the primary generator or power line can result in an unanticipated mismatch between power generation and consumption. This discrepancy can trigger substantial and swiftly evolving alterations in power distribution, angular speed, load flow, and the frequency of generators. The risks of an energy system collapse can be mitigated through automation, enabling rapid adjustments to generation and load capacities, as well as power flows, in the electrical network. This article justifies the utilisation of a power control method for high-voltage power line interconnections. The technology of hydro storage power plants and measurements of voltage phasors are employed. The potential for easing power flow restrictions and realising substantial economic benefits is supported by the results obtained using simplified dynamic model of the Baltic power system and Nord Pool electricity market model.

Decentralized Retrofit Model Predictive Control of Inverter-Interfaced Small-Scale Microgrids

In recent years, small-scale microgrids have become popular in the power system industry because they provide an efficient electrical power generation platform to guarantee autonomy and independence from the power grid, which is a critical feature in cases of catastrophic events or remote areas. On the other hand, due to the short distances among multiple distribution generation systems in small-scale microgrids, the interconnection couplings among them increase significantly, which jeopardizes the stability of the entire system. Therefore, this work proposes a novel method to design decentralized robust controllers based on a retrofit model predictive control scheme to tackle the issue of instability due to the short distances among generation systems. In this approach, the retrofit model predictive controller receives the measured feedback signal from the interconnection current and generates a control command signal to limit the interconnection current to prevent instability. To design a retrofit controller, only the model of a robust closed-loop system, as well as an interconnection line, is required. The model predictive control signal is added in parallel to the control signal from the existing robust voltage source inverter controller. Simulation results demonstrate the superior performance of the proposed technique as compared with the virtual impedance and retrofit linear quadratic regulator techniques (benchmarks) with respect to peak-load demand, plug-and-play capability, nonlinear load, and inverter efficiency.

The impact of titanium alloying on altering nanomechanical properties and grain structures of sputter-deposited cobalt for electromigration reliability enhancement

Cobalt (Co) has recently become a highlighted on-chip interconnection material for advanced metallization scheme of microelectronic circuits. Here, electromigration behaviors of sputter-deposited Co and Co(Ti; 0.9 at%) interconnection lines embedded in Si are comparatively studied. These lines were annealed (500 °C/30 min) prior to further accelerated electromigration testing under high current densities in the range of 3 × 107–9 × 108 A cm−2. A collection of the obtained electromigration failure lifetimes, current scaling factors and activation energies confirms a noticeable enhancement in the electromigration reliability of the Co lines by the added Ti. Results by scanning transmission electron microscopy (STEM) and nanoscratch testing reveal that 3–5 nm-sized Ti crystallites are uniformly dispersed in the Co-interconnect matrix, effectively inhibiting Co grain growth, promoting the formation of nanotwinned Co and elevating film’s mechanical properties for ensuring the electromigration reliability. With deteriorated hardness and adhesion energy, reduced planar defects and many big grains all spanning transversely the entire interconnect line, Co is vulnerable to electromigration failures, also giving accelerated thermally-induced interfacial diffusion and chemical reactions with the surrounding Si, as proven by depth-profiling secondary spectrometry and STEM analysis.

Economic and environmental impacts from the China-Korea power grid interconnection

China and Korea have planned a substantial power grid interconnection project, driven by a shared commitment to achieve their respective policy goals. This paper analyzes the economic and environmental impacts of this cross-border power grid interconnection and presents a comprehensive financial analysis of the project. We formulate a power system model that includes a planned submarine HVDC transmission line between two countries and study various scenarios by using hourly data. Our results demonstrate that the interconnection line operates with a remarkably high utilization rate, ranging from 98.90 % to 99.95 % across all analyzed scenarios. This high utilization rate suggests that the project holds significant economic potential, with estimated net present values ranging from $1,786 million to $3,019 million at a discount rate of 7 %. Furthermore, from the sensitivity analysis on carbon price, discount rate, and transmission capacity, we show how the financial outcome of the project is affected by the change in these parameters. Finally, we discuss the consequence of imposing an additional constraint on the carbon emission to our model and then, minimizing the overall carbon emissions subject to keeping the overall cost without the interconnection. In both variations, we show that the two countries can achieve their policy goals without increasing carbon emission.

Estimation of bandwidth, voltage swing and DC coefficients for VLSI interconnects: current mode technique

ABSTRACT Necessity of bandwidth requires the effective use of it for high speed data transmission and faster read/write operation in memory cells. In this paper the transfer function expressions for RC interconnect line is presented for resistive load. The line delay, bandwidth and step response for current and voltage mode signalling is formulated. The current mode and voltage mode signalling provides the 3-dB bandwidth of 6.8 GHz and 3.1 GHz, respectively. An interconnect line modelled as either RLC or RC line depending upon input signal rise time, damping, and range of interconnect length with significant inductance effect is investigated for global interconnect lines. Low swing for column bit line in memory architectures is very important and estimated in terms of dc coefficients. For RC global interconnect of 10 mm, a swing of 0.382 V is obtained for current mode signalling, when a power supply of 1.8 V is applied to the network. DC coefficient and steady state value has been obtained which is significant for power computation on column bit line. It is also analytically validated by SPICE and MATLAB simulations.

P‐76: The Influence of Bending FFC Transmission Line on High‐Speed Signal Channels

Generally, display devices interconnect FFC transmission lines with circuits to form a transmission line network system to achieve data communication between Tcon and Driver. Due to the limitations of the external shape and internal space structure of the display device, the FFC transmission cable presents a curved shape from 0 to 180 degrees during the wiring process. Under the action of spatial electromagnetic fields, the display device will involve the field‐circuit hybrid problem of electromagnetic coupling of the FFC transmission line's bent line and circuit conduction interference, which will cause severe electromagnetic interference(EMI), resulting in deterioration of the high‐speed channel signal at the receiving end and even inability to correctly restore and decode the signal, thus causing signal distortion, which in turn leads to display image distortion or pixel loss.

Coordinated Control of Intentional Islanding and Phase Sequence Exchange for Enhancing Transient Stability of Isolated Power Grid

An isolated power grid (IPG) is electrically weakly connected to the utility power grid, and intentional controlled islanding (ICI) can secure IPG from external faults. Phase Sequence Exchange (PSE) is a recently developed emergency control technology in which power electronic devices are used to switch the three-phase sequence, thereby reducing the power angle of the generator by 120° and preventing the system from losing stability. This paper proposed a coordinated control scheme for PSE and ICI. After the system is disturbed, the local measurement of the interconnection line between IPG and the utility grid is used to assess the system's stability. PSE is adopted to adjust the power flow direction to reduce the transient energy of IPG. At the same time, using the internal measurement of IPG, the transient energy of IPG is calculated in real-time, and the critical energy is rolling refreshed based on offline information. After PSE reduces the energy of IPG to lower than the critical energy, IPG is safely disconnected from the utility grid. The proposed scheme needless to adjust the internal generator or load of IPG and is verified on the real-time digital simulator (RTDS) platform with a PSE prototype.

Coordination of Controllers to Development of Wide-Area Control System for Damping Low-Frequency Oscillations Incorporating Large Renewable and Communication Delay

The modern power systems incorporate high penetration of renewable is a large, composite, interconnected network with dynamic behavior. The small disturbances occurring in the system may induce low-frequency oscillations (LFOs) in the system. If the (LFOs) are not suppressed within a stipulated time, it may cause system islanding or even blackouts. Hence, it is essential to investigate the behavior of the system under various levels of disturbances and control action must be taken to damp these oscillations. The established approach to damping the LFOs is by installing power system stabilizers (PSS). PSS uses the local signals from generators to control the oscillations. The dominant source of inter-area oscillations in power systems is due to overloaded weak interconnected lines, converter-interfaced generation, and the action of the high gain exciter present in the system. Consequently, wide area control is needed to control the inter-area oscillations existent in the system. This paper developed a coordinated design of conventional PSS, static compensator, renewable converters, and wide area controller for damping the local and inter-area oscillations in renewable incorporated power systems. The performance of the developed controller is evaluated through the time domain analysis and eigenvalue analysis. A comparison of the introduced controller has been done with other standard conventional methods. The choice of input signals for the wide area controller from the wide-area measurement system is done based on the controllability index. Additionally, the location of the controller must be identified to dampen the inter-area oscillations in the system. In this paper, the controllability index is calculated to find out the highly affected wide area signals for considering it as the feedback signal to a developed controller. The location of the controller is recognized by computing the participation factor. The developed controller has experimented on renewable incorporated large study power systems when time delay and noise are present in wide area signals.

Investigating the potential of Machine Learning for fault location on Inverter-Based Resource interconnection lines: Insights and recommendations

Given the increasing penetration of Inverter-Based Resources (IBR) and the impacts of these generators on existing fault location functions, this paper explores the potential of Machine Learning (ML) for designing one-terminal fault locators applied to systems with IBRs. For the studies, a system with a widely used topology for IBR interconnection to a transmission grid is modeled in PSCAD software, considering fault scenarios on the interconnection line with varying fault parameters, in addition to different IBR controls/topologies, grid short-circuit levels and signal noise levels. Besides the investigations on correctly choosing the attributes extracted from the signals for training ML methods, which introduces the concept of learning based on the existing method’s response, the studies cover performance assessments of 35 ML methods for the fault location task, indicating the most suitable ones, and studies about the influence of the training set size on the ML methods performance. Moreover, comparative performance analyses are conducted between the ML-based methodology and state-of-the-art fault locators, highlighting the benefits of the ML-based approach in reducing errors obtained in the fault location task. Finally, the paper recommends stages for applying ML-based methods to real systems, besides providing insights and recommendations on such practical applications.

МЕЖДУНАРОДНАЯ НАУЧНО-ПРАКТИЧЕСКАЯ КОНФЕРЕНЦИЯ «РАЗВИТИЕ СИСТЕМЫ НАКАЗАНИЙ, НЕ СВЯЗАННЫХ С ИЗОЛЯЦИЕЙ ОСУЖДЕННЫХ ОТ ОБЩЕСТВА. ВВЕДЕНИЕ ИНСТИТУТА ПРОБАЦИИ В РОССИЙСКОЙ ФЕДЕРАЦИИ» (15 НОЯБРЯ 2023 ГОДА)

On November 15, 2023, the Department of Penal Enforcement Law and the organization of educational work with Convicts of the Academy of the Federal Penitentiary Service of Russia within the framework of the VI International Penitentiary Forum «Crime, Punishment, Correction» held an international scientific and practical conference «Development of the system of punishments not related to the isolation of convicts from society. Introduction of the Institute of Probation in the Russian Federation». The features of the scientific event were a comprehensive discussion of numerous theoretical and applied issues of improving the effectiveness of the execution of criminal penalties, directions for the development of penitentiary, executive and post-penitentiary probation, as well as the presence of two insufficiently interconnected lines of influence implemented by institutions and bodies executing punishments (in the context of the correction of convicts and the use of various forms of probation), having a common goal in the form of prevention the commission of new crimes.

Supply Nets: The Logistics of Seafarer Abandonment

AbstractThis paper studies the infrastructural and organisational forms that facilitate labour exploitation within maritime logistics. My entry point is the rising wave of seafarer abandonments, which I approach not as isolated incidents of mismanagement but as an intensification of the flexibilising tendencies underpinning contemporary capitalism. I trace the recent history of these dynamics, examining their effect on shipping labour. I then investigate some of the specific legal and economic mechanics of shipping, focusing on debt, insurance, and bordering. Using supply chain mapping software, I study supply systems in a way that centres labour rather than the commodities being moved. I close by claiming that abandonments are not an accident, but an inevitable endpoint of a system designed to precaritise labour while protecting shipowners’ profits. Against this, I sketch out a new way of conceiving of supply chains—as supply nets, matrices of interconnected lines, prone to becoming tangled.

Double‐Sided, Thin‐Film Microelectrode Array with Hemispheric Electrodes for Subretinal Stimulation

AbstractComponents in neural implants, such as the electrode array and stimulator circuit, are often fabricated discretely. This modular fabrication scheme offers flexibility during development but poses difficulties during assembly, as components must be compactly integrated for implantation. It is particularly difficult in cases where the electrode array is required to have a high number of channels, such as in retinal prostheses. This paper presents the development of a parylene C‐based, double‐sided microelectrode array with 294 hemispheric electrodes for subretinal stimulation. The bonding pads on the bottom side of the double‐sided array are connected with electrodes through vias, eliminating the interconnection lines. The array can be integrated with a stimulator circuit through pad‐to‐pad bonding, resulting in a compact implant. The hemispheric electrodes are fabricated using thermally reflowed photoresist infillings, through which the height and width of the hemispheres can be easily controlled. The long‐term stability and biocompatibility of the materials and methods used to fabricate and package the electrodes are demonstrated in in vitro and in vivo environments over months. Finally, subretinal stimulation by the developed electrodes is successfully demonstrated using in vitro retinal patches from mice and monkeys.

A multi-phase-field model of void crossing grain boundary under electromigration-induced anisotropic surface diffusion in interconnects

Under the external electric field, the voids in polycrystalline interconnect lines will exhibit different morphology evolution when crossing grain boundary. Predicting the void crossing process caused by electromigration is an important aspect to improve the reliability of miniaturized integrated circuits. Based on the basic theoretical framework of microstructural evolution in solid materials, a new multi-phase-field model is established in this paper to simulate the process of void crossing grain boundary under anisotropic surface diffusion caused by electromigration in bicrystal interconnect line. Through asymptotic analysis, the compatibility of the multi-phase-field model with the sharp interface model in the limit case is proven. The corresponding finite-element program is developed and the reliability of the model is verified by comparing the numerical simulation with the theoretical solution. The results indicate that the process of void crossing grain boundary is governed by the crystal orientation and the misorientation difference of two adjacent grains. Under different misorientation differences, the void in (110) crystal orientation has two evolutional bifurcation trends: void splitting and tilting drift, while the void in (100) and (111) crystal orientation always remains as a whole and drifts along the direction of the electric field. The void in (111) crystal orientation is the easiest to cross the grain boundary, the fastest to cross the grain boundary, and the influence of the misorientation difference is minimal. This can prevent the void from being pinned by the grain boundary and extending along the grain boundary to cause failure, so as to effectively improve the reliability of the interconnects and extend the service life of the integrated circuit.

A coordinated restoration method of three-phase AC unbalanced distribution network with DC connections and mobile energy storage systems

In the rapidly changing domain of hybrid AC/DC urban distribution networks, this research unveils a groundbreaking method for the restoration of three-phase unbalanced systems by astutely harnessing the unique potential of DC line interconnections. At the heart of this innovation lies the synthesis of symmetrical Second Order Cone Programming (SOCP) with a sophisticated topology search technique, a union that offers a precise depiction of complex three-phase power flow with network restoration while simultaneously accelerating computational processes. Building upon this foundation, our approach places significant emphasis on the utilization of adaptable DC power control, coupled with the optimal deployment of mobile energy storage systems (MESSs), to ensure a harmonized power balance during critical interruptions. These strategies converge to prioritize the restoration of vital loads, especially those with high weighting factors, thereby significantly augmenting the network’s resilience, particularly in contexts vulnerable to disasters. The corroborative numerical results, as delineated in our study, highlight the distinct advantage and effectiveness of our methodology over prevailing practices in fortifying grid resilience against serious adversities.