Interconnect Power Research Articles

Power Quality Enhancement in High-Voltage Transmission Systems Using STATCOM by Type 1 and Type 2 Fuzzy Logic Controllers

The continuing growth of load demand leads to increased power system complexity and interconnections. During faults and abnormal operating conditions, conventional power systems change the load flow in transmission lines, which may cause voltage drops or swells, and other power quality issues. Voltage regulation is connected to reactive power compensation in system busbars, and fixed capacitor banks are usually used for this purpose, but they are not flexible and dynamic enough to meet the power quality requirements. With power electronics development, flexible alternative current transmission systems (FACTS) became a popular solution for power quality improvement and power transmission capability increment in power systems, and FACTS can be categorized into series and shunt systems. In this study, STATCOM was used to improve the voltage profile in part of Iraq’s high-voltage transmission system during abnormal operating conditions, such as sudden load addition and removal, which causes voltage dip and voltage swell. Type 1 fuzzy logic controller and type 2 fuzzy logic controller were used as the outer controller in the STATCOM; both controllers were able to regulate the voltage magnitude by reducing the voltage dip from 1.32 to 0.4%, voltage swell from 1.02 to 0.5%, and voltage THD at the connecting point did not exceed 3%, indicating that SATACOM with FLC improves the voltage profile under different operating conditions.

Korean Offshore Wind Electrical Power Generation: Current Status and Prospects

Offshore wind power generation is recognized as an environmentally friendly and sustainable energy source, rapidly advancing with governmental support in many countries such as Denmark, China, Germany, and across Europe due to its high energy stability, potential, and economic benefits. South Korea has set a target of 17.7GW for wind power generation through its Renewable Energy 3020 Implementation Plan, aiming to supply 12GW of offshore wind power by 2030. However, Korea faces slower development compared to overseas counterparts due to various obstacles including lack of community acceptance, low business feasibility, complex approval processes, and insufficient supply chain. This study identifies fundamental reasons behind Korea's sluggish growth in offshore wind power generation and proposes the following solutions through comparison with leading international cases. 1) Strengthening positive communication with residents by clearly articulating the value and benefits of offshore wind power projects to address community acceptance issues. 2) Resolving low business feasibility issues through the establishment of government-led incentive programs and support measures. 3) Streamlining approval processes to mitigate delays and cancellations in project implementation. 4) Expanding domestic market size and enhancing efficient power interconnection to address supply chain deficiencies.

Configuration of Man’s Position within Patriarchal Structure in Nepalese Society

Patriarchy is a powerful philosophy and structure of male domination and supremacy. It is not new, nor is the recognition of women’s demoralized existence well-established patriarchal system and it embraces that there is an inferior position of women since historical period. Patriarchy is a social system in which men use, abuse, control, oppress and exploit women. The concept of patriarchy highlights the interconnection of different aspects of gender discrimination and women are often underprivileged in many areas of social existence. Theories and philosophies of patriarchy explore the division of interests between most men and women formed by the social system of gender perceptions, practices and relationships. Gender is a relationship of power and inequality and not merely of variation. There are various supplementary expressions that have extremely related meaning to patriarchy. These incorporate gender command, gender arrange, gender display and sex-gender formulation. They are comparable in pointing to the powerful interconnection of various sphere of influence of gender discrimination. Analyses of patriarchy differ as to whether men's position as head of the household and family or society or state entity is recognized as the key to their potentiality to rule and oppress, or whether the institutional features of men's supremacy are pictured and imagined. In this context, this study provides an analysis of the understanding and accepting of man's position within existing patriarchal structure in Nepalese societies inside the background of gender standpoints and different educational status. It also tries to explore the common judgments and ruling ideologies on patriarchy and its practices and social insights of gender relationships.

How language power, white subalternity and compressed modernity frame highly-skilled non-Western migrants in an East-German company: insights from multi-sited ethnography

PurposeThis paper shows the benefits of multi-sited ethnography for global migration studies in management, in particular when cosmopolitan self-initiated expatriates meet a local setting.Design/methodology/approachThe author conducted a multi-sited ethnography to trace how a local East German research organization’s well-intended approach to integration becomes condescending.FindingsHighly skilled non-Western migrant employees who represent English-language cosmopolitanism are framed as negatively “foreign” by corporate discourses and practices. This phenomenon can only be understood if one follows the interconnections of language power, White subalternity and compressed modernity and if one considers the immediate surroundings, the historical context of East German identity and wider migration frames in Germany.Research limitations/implicationsMulti-sited ethnography, if power-sensitive and historically-aware, is suitable for understanding the multi-level phenomenon of global migration and identifying limiting framing-effects on management and organizations. Researcher standpoint is both its strength and its limitation.Practical implicationsManagers and companies can “imagine otherwise” and move beyond the unquestioned dominant frames limiting their problem analyses and, consequently, their strategies and actions.Social implicationsManagers and companies are enabled to move beyond individual- and corporate-level approaches to managing migration at work and can thus take up full social responsibility in the sense of good corporate citizenship on a global level. Global mobility researchers can work towards an inclusive migration theory.Originality/valueMulti-sited ethnography, in particular, one that is power-sensitive and historically aware, is an approach not yet applied to migration in the context of management and organization. By means of an example, this paper illustrates the value of this approach and enables researchers to understand its main principles. Compressed modernity and White subalternity are introduced as novel concepts structuring migration, and language power emerges as relevant far beyond the scope of the multinational corporation.

Interstate power interconnection along with carbon dioxide emission constraint collaboration: Effective tool for low-carbon electric power expansion in Northeast Asia

Interstate electric power integration with the formation of interstate electric ties and power interconnection in Northeast Asia has been studied for several years. Research has examined the directions, indicators, costs, and systemic (integration) benefits (technical, economic, environmental, etc.) of forming such ties and grids. Studies conducted in different Northeast Asia countries have shown that despite the significant investments required to create an interstate electric ties infrastructure, which serves as the basis for interstate power grids and electricity markets development, participants of these interstate power grids and markets gain substantial benefits. These include reduced needs for installed and reserve generation capacity, lower electricity prices, increased overall flexibility of power resources, and accordingly, greater capability to integrate renewable energy sources. This results in reduced carbon dioxide (CO2) emissions from fossil fuel power plants. The latter undoubtedly contributes to achieving the sustainable development goals set by the United Nations and reducing anthropogenic climate impact, which many countries globally (including Northeast Asia) have targeted via announced carbon neutrality by 2050–2060. The main target of the article is to conduct and present new multi-scenario study on forming a potential Northeast Asia’s interstate power grid under national and grid-wide (for the entire power system interconnection) carbon emission constraints. The mathematical model of electric power system expansion and dispatching was modified to account for carbon dioxide emission constraints and used for the study. The results of the study showed that the creation of interstate power grid in Northeast Asia accompanied by climate change collaboration among countries to control carbon dioxide emission would lead to effectively constraining of carbon dioxide emission in the subregion, which is the novelty of the study. The results of the study are useful and applicable for choosing particular ways, options, stages of formation and expansion of low-carbon power system interconnection in Northeast Asia.

Neutralized, intense-ion beams for fusion

A charge- and current-neutralized, intense-ion beam (IIB) will propagate undeflected in a magnetized plasma by the E×B , or diamagnetic, drift for a distance large compared to the beam-ion gyro-radius. This propagation occurs because of collective plasma effects when the beam-energy density is sufficient to sustain the polarization-electric field, or diamagnetic-screening currents. Our principal interest is the E×B drift, with β=Ebeam/Efield<1 . IIBs are characterized by parameters in the range: 0.1–2 MeV ion energy, 1–100 MA m−2 ion-current density, and 17–350 kW average power produced on repetitively-pulsed systems. Multi-MW average-beam power is possible with appropriate modifications to the power supply and ion-source/accelerator. IIBs can be focused geometrically, and/or magnetically, to spot sizes of the order of a few cm’s and their angular divergence is typically, ∼15 mRadians, suitable for long-range propagation in a vacuum beam-line. IIBs lose energy and momentum in the same manner as particles injected by a neutral-beam injector (NBIs), hence could be useful for fusion applications, including: heating, current drive, fueling, profile modifications, etc and such applications have yet to be thoroughly studied. Summarized here are the physical principles accounting for IIB propagation; ion-source designs used to produce the IIB; and pulsed-power methods for energizing the IIB accelerator. This technology base informs scalable metrics for the ion-source/accelerator (excluding the HV power supply and interconnects) used in a conceptual injector that provides the same ion energy and injected power (1 MeV, 17 MW) as NBIs used on ITER. A comparison indicates that the IIB injector would be much smaller in size, lower cost, and have much greater efficiency, while also providing for real-time modulation of the beam energy and intensity and the use of small-diameter injection ports that could minimize fuel contamination and magnetic-field leakage between the IIB injector and tokamak.

Can power interconnection buffer economic policy uncertainty? Evidence from countries along the Belt and Road

Regional power interconnection significantly fosters a green economy and sustainable development. It could also promote regional collaboration. This study examines the impact of economic policy uncertainty on electricity trade among the Belt and Road countries from 2000 to 2020. The findings reveal that economic policy uncertainty positively affects electricity trade within these countries, implying that most countries secure energy supply by sustaining or increasing their power trade with other connectable countries to counteract economic policy uncertainty. Economic policy uncertainty coefficients in middle-income countries will be greater than those in high-income countries. Middle-income countries have less mature electricity markets and greater potential for interconnection growth. This study provides implications for countries along the Belt and Road if they foster regional power interconnection through infrastructure construction and regional unified standard formulation.

A Joint Electricity Market-Clearing Mechanism for Flexible Ramping Products with a Convex Spot Market Model

A high proportion of renewable energy access makes the net load of the power system volatile and uncertain, increasing the demand for the ramping capacity of the power system. Traditional electricity spot markets compensate for the power imbalances caused by an insufficient ramping capacity through traditional flexibility services such as ancillary services and interconnection power. However, conventional flexibility services may lead to frequency deviations in the power system, increased response costs, spikes in electricity prices, and dramatic price volatility in the traditional spot market. To solve the above problems, this paper proposes an FRP and convex electricity spot market joint clearing (FCESMJC) market mechanism. The FCESMJC model can more accurately represent the relationship between electrical power output and the price of electricity and reduces the number of spikes in electricity prices. In addition, a novel FRP pricing method is proposed to compensate FRP market participants for their FRP costs more reasonably. Additionally, the difference in system performance is provided by comparing the energy prices, pricing method, clearing prices, and system costs in the FCESMJC method and the traditional electricity spot market. The FCESMJC system reduces the total system cost by 18.6% compared with the electricity spot market. Numerical experiments are simulated on the IEEE 14-bus test system to validate the superiority of the proposed model.

Security load frequency control model of interconnected power system based on deception attack.

The interconnected power system connects the power grids of different regions through transmission lines, achieving power interconnection and resource sharing. However, data is transmitted through open power networks and is more susceptible to network attacks. To improve the stability of interconnected power systems under deception attacks, three scenarios of system security load frequency control were studied. Based on the construction of a dynamic model of load frequency control, an event-triggered strategy was used to reduce the communication frequency between nodes, resulting in a reduction in the amount of network transmission data. A sliding mode controller was constructed to solve the problem of event-triggered sliding mode security load frequency control. Elastic event-triggered sliding mode load frequency control for interconnected power systems under mixed attacks. The simulation results showed that using the load frequency control model triggered by events, the load frequency deviation of the interconnected power system can be stabilized at around 12 seconds, effectively saving the cost of network resources. Under the regulation of the load frequency control model based on sliding mode control, the interconnected power system stabilized in 10 seconds, reducing the load of network transmission. The elastic event-triggered sliding mode load frequency control model can ensure stable transmission of power data under various attacks and has good anti-interference performance. The results of this study have played an important role in achieving the stability of power resource supply. Compared with previous studies on individual power systems, this study solves the attack problem of interconnected power systems and considers the frequency control problem of system security loads under mixed attacks, enabling the system to recover stability faster.

Performance analysis of voltage source converter based high voltage direct current line under small control perturbations

High voltage direct current (HVDC) systems provide important advantages; among them the ability to transmit enormous amounts of electrical power over great distances at low cost. As a result, planners of power systems consider it as a viable choice for power transmission and interconnection of asynchronous networks. Depending on HVDC grids, continental/super grids have been recently constructed to promote global economic development. The study described in the paper focuses on the behavior of a voltage sourced converter (VSC) based HVDC transmission system comprising three arms-neutral point clamped (NPC) converters interconnecting two asynchronous alternating current (AC)networks. In addition, the system components, and the vector control strategy of active/reactive powers and direct current (DC)bus voltage are simulated in MATLAB/Simulink under varying situations by adjusting the controller’s settings. The study records and analyzes AC/DC voltages and active/reactive powers at two converter stations undervarying power and voltage conditions. The results of the study provide key performance indicators, such as settling time (tsett), steady state error (SSE), overshot/undershoot (OS%/US%), and correlation factor (CF), which demonstrate the robustness of thesystem’s control.

Power investment and transmission network expansion in China and its neighbouring countries towards carbon neutrality

Transnational power cooperation contributes to promoting the large-scale use of renewable energies in Asia, but how to develop the structure of power transmission network deserves careful investigation. This paper thoroughly investigates the structure of power investment and transmission network in China and neighbouring countries, aiming to promote the large-scale use of renewable energies around Asia. Various power-generation and power-transmission technologies are considered in detail, and transnational power interconnection risk cost and carbon emission cost are embedded into a bottom-up optimization model. The future power-generation structures and networks installed under various policy scenarios are analysed in detail, and the corresponding economic, carbon emission reduction and renewable energy consumption benefits are evaluated. The results show that power transmission between China's internal regions and neighbouring countries can save $56.7 billion for the entire power system through the large-scale grid integration of renewable energy. The installed capacities of wind power, solar power, and hydropower renewable energy power generation could be increased by 141 GW, 163 GW, and 58 GW, respectively. The construction of transnational transmission lines from Central Asia to Northwest China, Mongolia to North China, the Russian Far East to Northeast China, and Northeast China to South Korea could effectively promote the utilization of renewable energy in the Russian Far East, Mongolia and Central Asia and further reduce carbon emissions in China, Japan and South Korea.

Nonlinear state feedback-synergetic control for low frequency oscillation suppression in grid-connected pumped storage-wind power interconnection system

Aiming at enhancing the performance of suppressing low frequency oscillation in grid-connected pumped storage-wind power interconnection system (PS-WPIS), the nonlinear state feedback-synergetic control (NSF-SGC) governor is studied. Firstly, the nonlinear mathematical models of grid-connected pumped storage power system (PSPS) and PS-WPIS are established. Then, the NSF-SGC strategy and macro variable determination method are proposed, and the NSF-SGC governor equation is derived. Furthermore, the action mechanism, regulation and damping characteristics of NSF-SGC governor in grid-connected PSPS and PS-WPIS are explored. Finally, the sensitivity and robustness of NSF-SGC governor are illuminated. The results show that, the proposed NSF-SGC strategy is superior to the proportional-integral, NSF and SGC strategies in regulation quality, and can significantly suppress low-frequency oscillation. The stability of grid-connected PSPS can be prominently improved by selecting smaller linear and time parameters, and a larger absolute value of nonlinear parameter of NSF-SGC governor. The NSF-SGC governor with dual macro variables enhances the damping characteristics of grid-connected PS-WPIS. Appropriate parameters of NSF-SGC governor can enhance the regulation performance of grid-connected PS-WPIS. Noise and parameter sensitivity analysis provide a guidance for improving system stability. The NSF-SGC governor has strong robustness under the variations of hydraulic, mechanical and electrical parameters.

Stability and multi-frequency dynamic characteristics of nonlinear grid-connected pumped storage-wind power interconnection system

Stability and multi-frequency dynamic characteristics of nonlinear grid-connected pumped storage-wind power interconnection system

Resilient Model Free Adaptive Distributed LFC for Multi-Area Power Systems Against Jamming Attacks.

This article is concerned with distributed resilient load frequency control (LFC) for multi-area power interconnection systems against jamming attacks. First, considering uncertainties and high dimension nonlinearity, the model-free adaptive control (MFAC) model is adopted for the power system, in which only input and output (I/O) data are used. Second, jamming attacks are modeled in a stochastic process, and a multistep predictive compensation algorithm is developed to mitigate the impact of jamming attacks. Then, the distributed MFAC protocol with predictive compensation algorithm is designed such that the frequency tracking errors under the predictive compensation algorithm of multi-area power interconnection systems converge consensually into a small neighborhood of origin in the mean square sense. Simulation results show the effectiveness of the approach.

Cooperative control strategy for frequency regulation of wind-pumped storage system considering wind speed partition

In order to solve the problem of system inertia reduction and frequency response degradation caused by large-scale wind power interconnection, a strategy is proposed. This strategy incorporates a joint system model composed of doubly-fed wind turbine (DFWT) and variable speed pumped storage (VSPS), utilizing a fuzzy controller to dynamically determine the virtual inertia coefficient of the wind-pumped storage system based on the frequency state of the system, and adjusts the frequency-regulation participation factor of the DFWT in real time according to the operating conditions of it. The simulation results show that the proposed strategy can not only significantly improve the frequency nadir, speed up the system frequency and each generating unit in the system to restore to steady state, but also avoid the second frequency drop (SFD) caused by the wind farm out of primary frequency regulation (PFR), and improve the stability of the system frequency.

Simultaneous Switching Noise Effects in Graphene-Based Power Distribution Networks

The simultaneous switching noise (SSN) effects in graphene nanoribbon field effect transistor (GNRFET) based ternary circuits are presented in this study. The performance in terms of SSN induced peak noise and propagation delay on power and ground rails are investigated in multilayer graphene nanoribbon (MLGNR) bundled power interconnects using Hewlett simulation program with integrated circuit emphasis (HSPICE) simulator. Furthermore, these investigations are compared to the copper (Cu) and multiwalled carbon nanotubes (MWCNT) based power interconnects. From the results, it is noticed that the proposed MLGNR interconnects shows performance improvements up to 74.9% and 33.8% over the Cu and MWCNT interconnects. Moreover, the SSN peak noise and delay are investigated for different interconnect lengths from 200 μm to 500 μm. It is observed that the SSN noise on power and ground rail is reduced and propagation delay is increased as interconnect length is increased.

An interconnect-free micro-electromechanical 7-bit arithmetic device for multi-operand programmable computing

Computational power density and interconnection between transistors have grown to be the dominant challenges for the continued scaling of complementary metal–oxide–semiconductor (CMOS) technology due to limited integration density and computing power. Herein, we designed a novel, hardware-efficient, interconnect-free microelectromechanical 7:3 compressor using three microbeam resonators. Each resonator is configured with seven equal-weighted inputs and multiple driven frequencies, thus defining the transformation rules for transmitting resonance frequency to binary outputs, performing summation operations, and displaying outputs in compact binary format. The device achieves low power consumption and excellent switching reliability even after 3 × 103 repeated cycles. These performance improvements, including enhanced computational power capacity and hardware efficiency, are paramount for moderately downscaling devices. Finally, our proposed paradigm shift for circuit design provides an attractive alternative to traditional electronic digital computing and paves the way for multioperand programmable computing based on electromechanical systems.

Power Grid Fault Diagnosis Method Based on LightGBM

With access to distributed power generation and interconnection between regions, China’s power system structure is becoming increasingly complex, and the requirements for power grid dispatching capacity are getting higher and higher. When the power grid fails, a large amount of alarm information appears in the monitoring window, which needs to be processed and classified first to speed up the fault diagnosis and processing. Therefore, this paper proposes a power grid fault diagnosis method based on LightGBM. First, after pre-processing the power grid alarm information, Word2vec is used to vectorize the text, and then the LightGBM model is used to process the text, extract the information features and continue to train. Finally, realizing the three classifications of such simple faults as the transformer fault, bus fault, and line fault. Finally, through the test and verification of the actual power grid case data, it is verified that the method can effectively classify simple faults and meet the needs of the actual power grid online diagnosis.

Preface

The International Conference on New Energy and Power Engineering is a leading international conference held annually. The conference is committed to providing an academic platform for the communication and academic exchange among participants from the fields related to new energy and power engineering. It is a great opportunity to promote academic communication and collaboration for the delegates worldwide.This volume contains the papers presented at the 2nd International Conference on New Energy and Power Engineering (ICNEPE 2022), held during November 18th-20th, 2022 in Qingdao, China (virtual event). ICNEPE 2022 promoted the information exchange among researchers, engineers, and practitioners around the world, promoted the development and application of theory and technology in new energy and power engineering, and established business or research contacts for participants to seek global partners in the future.The online conference was composed of keynote speeches, oral presentations, and academic investigation, attracting about 100 leading delegates from all over the world. We have invited four sophisticated professors from different countries and regions to perform keynote speeches. Among them, Prof. Hamid BENTARZI from University M’hamed Bougara Boumerdes, Africa delivered a keynote speech on Micro-Synchro-Phasor Measurement Unit: Developments and Trends. In the presentation, he mainly introduced two points: a) Development of μPMU with precise time stamping of measurements via GPS to allow the comparison of voltage phase angle δ (i.e., the precise timing of the voltage waveform) at different locations, on hardware side. b) Development of many practical applications using this new type of information provided by μPMU in the distribution network context including the integration of intermittent renewable generation such as distributed control, adaptive protection and cyber-security of the electric grid. All the keynote speakers made dramatic and brilliant speeches and shared unique experience and insights, and we are hoping the pandemic soon come to an end and we could see each other face to face next year.We are glad to tell you that we have received a large quantity of submissions in the areas of new energy and power engineering. After rigorous review by related top experts and review rebuttal process, some excellent papers were accepted and covered in the proceedings, including but not limited to the following topics: Mechanical Dynamics and Vibration, Renewable Energy Technologies and Systems, Energy Management, Combined Cycle Power Plants, Asynchronous Generation and Interconnect, Tidal Power Plant Design, etc.On behalf of the Conference Organizing Committee, we would like to thank the Academic Committees and external reviewers for their hard work in reviewing and selecting papers. And we would like to acknowledge all of those who supported ICNEPE 2022. In particular, our special thanks go to the Journal of Physics: Conference Series. We sincerely hope that the ICNEPE 2022 turned out to be a forum for excellent discussions that enable new ideas to come about, promoting collaborative research.The Committee of ICNEPE 2022List of Committee member is available in the pdf.

Wavelet multiscale principal components and traveling waves enabled machine learning technique for protection of MT-HVDC systems

The interconnection of renewable energy sources to conventional power grids is widely recognized and promoted by the deployment of high voltage direct current (HVDC) technology. One of the biggest challenges associated with the HVDC systems is the rapid rate of rising DC fault currents, resulting in the immediate collapse of the converter stations. Conventional schemes of AC protection and low-speed DC protection are not worthy and mature because of the abrupt rising characteristics of DC currents. Therefore, protection techniques are being developed for reliable bulk power transfer and interconnection of unsynchronized grids via DC links. Timely identification, classification, and determination of location are the most fundamental characteristics of any protection scheme. This research paper proposes a machine learning-based protection method that establishes a rapid and reliable solution addressing the drawbacks of existing protection schemes. A multi-terminal high voltage direct current (MT-HVDC) test system is designed in Matlab/Simulink. Pole-to-ground and pole-to-pole faults are applied at different fault locations to assess the validity of the proposed algorithm. For this, DC voltages and currents are measured and analyzed. Power spectral analysis of traveling waves and Wavelet multiscale principal components analysis are employed for the extraction of featured data to classify and locate the DC faults. This reduced dimensional featured data is utilized for training and testing the support vector machine learning algorithm to analyze the accuracy of the proposed protection technique. Simulation results confirm the accuracy of rapid identification, classification, and location of DC faults.