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The construction industry has become one of the main drivers of the increase in carbon emissions and subsequent climate change. In this study, we focused on building carbon neutrality design and used CiteSpace V.6.2.R2 to conduct bibliometric analysis of published papers (2008–2023). After the initial screening, 280 pieces of relevant literature were obtained, including reviews, research papers, and case studies. Following further screening and excluding duplicate literature articles, 50 pieces of literature were ultimately selected as references for this paper, covering various aspects of key scientific issues, implementation approaches, and emerging research frontiers in carbon-neutral design for buildings. The research results show that significant progress has been made in energy conservation, materials, structures, systems, and operations in the research on carbon-neutral design for buildings. However, there are still issues, such as unclear implementation paths for carbon-neutral design, incomplete lifecycle assessment of carbon-neutral design, and high cost of carbon neutrality technologies in current research. Therefore, further research on the overall concept of carbon-neutral design, the progress and implementation of carbon neutrality technologies, and the integration of carbon-neutral design with sustainable development concepts are necessary. To sum up, this paper presents a thorough overview of the advancements in carbon-neutral design for buildings, examines the existing research challenges, and suggests potential avenues for future research. This paper's findings can provide guidance for researchers, policymakers, and practitioners to promote the development and application of carbon-neutral design for buildings and to achieve sustainable development goals. [ABSTRACT FROM AUTHOR]

The shift toward renewable energy has become a global trend today. In the past, power producers or the private sector were encouraged to install renewable energy equipment mainly through incentives (e.g., feed-in tariff, tax credits). Some countries also impose "renewable portfolio standards", which mandate power producers to include RE. However, it is rare to see any mandatory requirements on electricity users anywhere in the world. Since 2018, Taiwan's government has started to draft the RPS-TW to establish such obligation; but as a new mechanism, the greatest challenge lies in formulating feasible requirements that are apt to Taiwan's circumstances. This study aimed to assist Taiwan's government in this effort by formulating content that was feasible and meets external expectations regarding the applicable entities, scope, and methods of fulfillment. Once the draft had been revised accordingly, the public (electricity users, environmental groups, general public) were actively consulted, and the draft was modified and optimized based on widely collected feedback. The regulations were ultimately promulgated on 31 December 2020. [ABSTRACT FROM AUTHOR]

In this paper, an adaptive fuzzy sliding-mode control (AFSMC) system is investigated for an islanded inverter to achieve a high-performance power supply. A sliding mode control (SMC) law is designed initially to obtain both the voltage tracking error and the current tracking error of the inverter involved, to realize both the output-voltage regulation and the current protection with global stability. Moreover, to deal with uncertainties in the practical inverter system without the chattering phenomenon, an adaptive fuzzy system embedded with a self-adjustive translation width is developed to replace the switch term of the SMC. In addition, the adaptation laws, derived from the Lyapunov stability theorem, adjust the AFSMC parameters online to guarantee optimal and robust performance. Furthermore, the superior control performance of the proposed AFSMC is verified by a numerical simulation in MATLAB, producing experimental results on the prototype in comparison with the conventional SMC. [ABSTRACT FROM AUTHOR]

Lithium batteries in the electric vehicles (EVs) reveal that the operating temperature and temperature uniformity within the battery pack significantly affect its performance. An efficient thermal management system is urgently needed to protect the battery module within suitable temperature range. In this study, the composite silica gel (CSG), coupled with cross-structure mini-channel cold plate (MCP) as the cooling system, has been proposed and applied in a battery module, which can provide a reliable method of controlling battery temperature with low energy consumption. The experimental and simulation results reveal that a composite silica gel-based liquid system can control the temperature below 45 °C and maintain the temperature difference within 2 °C at a 3C discharge rate. Besides, the CSG, coupled with the structure of reciprocal chiasma channels for the battery module, presents an optimum temperature-controlling performance among various cooling structures during the charge and discharge cycling process. This research is expected to provide significant insights into the designing and optimization of thermal management systems. [ABSTRACT FROM AUTHOR]

Real-time monitoring devices are popularly utilized in modern power grids. To ensure long-term operations of the monitoring systems under complex outdoor conditions, a reliable and stable power supply is essential. In this paper, a general analysis of domino wireless power transfer (WPT) systems with load-independent outputs is proposed to realize a constant power supply for the monitoring equipment. In addition, the methodology of analyzing the self-oscillating points of the proposed domino WPT systems is deduced. The availability and feasibility of the proposed analysis and control method are verified by both simulation and experiment results based on a four-coil WPT system. [ABSTRACT FROM AUTHOR]

The grid-connected inverter is a vital power electronic equipment connecting distributed generation (DG) systems to the utility grid. The quality of the grid-connected current is directly related to the safe and stable operation of the grid-connected system. This study successfully constructed a robust control system for a grid-connected inverter through a dynamic recurrent fuzzy-neural-network imitating sliding-mode control (DRFNNISMC) framework. Firstly, the dynamic model considering system uncertainties of the grid-connected inverter is described for the global integral sliding-mode control (GISMC) design. In order to overcome the chattering phenomena and the dependence of the dynamic information in the GISMC, a model-free dynamic recurrent fuzzy-neural-network (DRFNN) is proposed as a major controller to approximate the GISMC law without the extra compensator. In the DRFNN, a Petri net with varied threshold is incorporated to fire the rules, and only the parameters of the fired rules are adapted to alleviate the computational workload. Moreover, the network is designed with internal recurrent loops to improve the dynamic mapping capability considering the uncertainties in the control system. In addition, to assure the parameter convergence in the adaptation and the stability of the designed control system, the adaptation laws for the parameters of the DRFNN are deduced by the projection theorem and Lyapunov stability theory. Finally, the experimental comparisons with the GISMC scheme are performed in an inverter prototype to verify the superior performance of the proposed DRFNNISMC framework for the grid-connected current control. [ABSTRACT FROM AUTHOR]

In this paper, a feedback compensator (FBC) and a Feedforward compensator (FFC) are proposed to construct a novel compensated peak current mode control pulse width modulation (CPC-PWM) for primary-side controlled flyback converters. Using the proposed FBC, the PWM duty cycle of an abnormal operating flyback converter would be descended to limit the output current for reducing power dissipation. Using the proposed FFC, the effect of delay time would be descended to reduce the over-flow current for increasing the current accuracy. In this paper, the operating principle and mathematical model are described and analyzed. Then, the component values are well designed to satisfy the electrical specifications. Finally, a prototype is designed and realized to access system performance. The experimental results show that the proposed CPC-PWM can validate in a wide input voltage range and output short conditions, which also has good current accuracy and reduces power dissipation by about 68%. [ABSTRACT FROM AUTHOR]

The objective of this paper is to propose an active ripple filter (ARF) using the patented DC-side direct current control for eliminating the double-line-frequency current ripple in a single-phase DC/AC conversion system. The proposed ARF and its control strategies can not only prolong the usage life of the DC energy source but also improve the DC/AC system performance. At first, the phenomena of double-line-frequency current ripple and the operation principle of the ARF are illustrated. Then, steady-state analysis, small-signal model, and control loop design of the ARF architecture are derived. The proposed control system includes: (1) a DC current control loop to provide the excellent ripple eliminating performance on the output of the DC energy source; (2) a voltage control loop for the high-side DC-bus voltage of the ARF to achieve good steady-state and transient-state responses; (3) a voltage feedforward loop for the low-side voltage of the ARF to cancel the voltage fluctuation caused by the instability of the DC energy source. Finally, the feasibility of the proposed concept can be verified by the system simulation, and the experimental results show that the nearly zero double-line-frequency current ripple on the DC-side in a single-phase DC/AC conversion system can be achieved. [ABSTRACT FROM AUTHOR]

Accurately locating faults is quite important, especially when the geographical environment is complicated. If the exact location of the fault is not given, wrong route would be chosen, which will greatly slow down repair. This paper proposes an improved traveling wave method by compensating the electrical distance of transmission lines. The catenary model is constructed that considers parameters of the tower and the actual temperature. The actual line length is also derived by the catenary model. A 500 kV transmission line model is established by PSCAD/EMTDC. Various fault simulations are conducted and the results demonstrate that the presented method effectively reduces the error ratio of faulty segment positioning and locates faults with high accuracy. [ABSTRACT FROM AUTHOR]

This paper proposes an optimal placement model of ultra-high frequency (UHF) sensors for accurate location of partial discharge (PD) in gas-insulated switchgear (GIS). The model is based on 0-1 program in consideration of the attenuation influence on the propagation of electromagnetic (EM) waves generated by PD in GIS. the optimal placement plan improves the economy, observability, and accuracy of PD locating. After synchronously acquiring the time of the initial EM waves reaching each UHF sensor, PD occurring time can be obtained. Then, initial locating results can be acquired by using the Euclidean distance measuring method and the extended time difference of arriving (TDOA) location method. With the information of all UHF sensors and the inherent topological structure of GIS, the locating accuracy can be further improved. The method is verified by experiment, showing that the method can avoid the influence of false information and obtain higher locating accuracy by revising initial locating results. [ABSTRACT FROM AUTHOR]

Electricity plays a crucial role in the well-being of humans and is a determining factor of the economic development of a country. Electricity issues have encouraged researchers to focus on improving power availability and quality along with reliability. This pursuit has increasingly raised the intention to integrate renewable energy (RE) into power systems to curb the problem of energy deficiency. However, intermittency in the sources of RE supply coupled with fluctuating changes in demand with respect to time has induced high risk in maintaining system reliability in terms of providing adequate supply to consumers. Whilst an energy storage system (ESS) is not another source of electricity, it is proven to be effective and viable in solving the aforementioned issues. Thus, this paper comprehensively reviews the development of ESS technologies and discusses the benefits and real-life applications of these technologies. The concept of reliability in power systems is also explored to provide an improved understanding of this study. Lastly, notable studies that have addressed the reliability impact of ESSs on power systems are discussed. This review paper therefore is expected to provide a critical analysis of ESS developments, as well as recognize their research gaps in terms of reliability studies in modern RE-integrated power networks. [ABSTRACT FROM AUTHOR]