bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on energy storage charging piles based on improved genetic algorithm
Authors: Sun Ningbo
Published: February 2024

Aiming at the charging demand of electric vehicles, an improved genetic algorithm is proposed to optimize the energy storage charging piles optimization scheme. Firstly, the characteristics of electric load are analyzed, the model of energy storage charging piles is established, the charging volume, power and charging/discharging timing constraints in the charging process are considered, and the optimization is carried out by the improved genetic algorithm, and the profit of charging piles and user charging electricity charges are calculated, so as to obtain the possible optimal parameters, as well as the impact of the energy storage system on the stability of the power grid. Secondly, the analysis of the results shows that the energy storage charging piles can not only improve the profit to reduce the user’s electricity cost, but also reduce the impact of electric vehicle charging on the power grid load.
The influence of training datasets on LSTM-based irradiance prediction
Authors: Li Lei , Zhang Lei , Li Dengxuan , Zhang Weitao , Yue Han
Published: February 2024

In solar photovoltaic power generation, the prediction of solar irradiance is essential for minimizing energy costs and ensuring the provision of high-quality electricity. Deep learning models have recently gained popularity in the field, as numerous scholars have successfully employed them to predict solar irradiance. In line with this, this paper proposes three distinct methods for dividing the training dataset. Subsequently, these methods are employed in predicting solar irradiance using the LSTM-based model. Furthermore, an error analysis of the prediction results is conducted for each of the three models. The optimal training dataset division method is determined and proposed based on a comparison of the sizes of the three models using six error evaluation indexes.
Optimal power flow calculation method for regional integrated energy system based on double-layer optimization
Authors: Zhang Tianshuo , Zhao Yan , Liu Renshuo , Chi Huazhi
Published: February 2024

In this paper, a two-layer optimization calculation method is proposed to improve the practical application efficiency of the integrated energy system and to improve the different problems of power flow calculation. Firstly, the power flow model is constructed and the optimization function is established based on indicators such as economy and environmental protection. The two-layer optimization method is proposed by combining the quadratic programming method and the particle swarm algorithm. Then, the obtained operating conditions of each energy equipment are used as the input of the power flow. The processing of each device and the energy flow of the power flow network are calculated and the effectiveness of the algorithm is verified by MATLAB power analysis.
Using the modified one-dimensional model to predict the mixed oil tailing of refined oil pipeline
Authors: Xiao Fan , Wang Yubin , Yang Qi , Xiao Mengsi
Published: February 2024

The tailing phenomenon in refined oil pipelines leads to an increase in the amount of mixed oil, resulting in significant economic losses. Therefore, it is of great significance to identify the factors that affect tailing, clarify the development rules of tailing oil, and manage the operation of refined oil pipelines. This article proposes a method to modify a one-dimensional (1D) oil mixing model, which takes into account the influence of wall-attached oil detachment rate and trailing oil concentration on tailing. A theoretical model that can describe the asymmetric development of the mixing interface is presented, and the development of the mixing interface under different detachment rates is discussed based on this model. The results show that this model can describe the tailing phenomenon in oil mixing. As the wall-attached oil detachment rate decreases, the length of the mixing zone gradually increases, the amount of mixed oil increases, and the asymmetry of the mixing interface increases.
Optimal operation of electric-heat-gas-hydrogen integrated energy system considering source-load uncertainty
Authors: Zu Weican , Wu Zhi , Wang Haolin , Zheng Shu , Wu Yuanxi , Hu Pengcheng
Published: February 2024

Faced with the threat of global climate change crisis, increasing the use of hydrogen-enriched compressed natural gas (HCNG) and the utilization rate of renewable energy can both reduce the carbon emissions of the integrated energy system (IES). This paper establishes an electric-heat-gas-hydrogen integrated energy system (EHGH-IES) framework considering source-load uncertainty, and the natural gas pipe network in the traditional IES is transformed into a HCNG pipe network with a certain hydrogen blending ratio. An optimal operation model of the EHGH-IES considering source-load uncertainty is proposed in this paper. The chance constrained programming method is adopted to deal with source-load uncertainty. We pay attention to comparing different confidence coefficient and hydrogen blending ratio in terms of the changes in the cost of the IES. The results show that the total cost of the EHGH-IES will increase by considering source-load uncertainty and using HCNG pipeline, but will bring some stability and environmental benefits to the IES by them.
Study on the influence of expansion section parameters on the performance of compressed air energy storage system
Authors: Li Fengyu , Shu Yue , Liu Xiaoming , Xiao Jun
Published: February 2024

Compressed air energy storage (CAES) gains attention because of its promising future application. In this paper, the parameters related to the expansion section, such as the heat exchanger efficiency, the high-pressure storage tank outlet air temperature and the high-pressure storage tank outlet air pressure, are selected to study their effects on the performance and setting of the CAES system. The results show that with the change in heat exchanger efficiency, air temperature and pressure at the tank outlet, the compression and expansion stage numbers are significantly affected. Because of the influence of the change of compression and expansion stage numbers, the hot water residual temperature, the efficiency of the first cycle, the efficiency after multiple cycles, and the area of the heat exchanger have changed. It can be seen that the change of expansion section parameters mainly affects the system performance by affecting the setting of compressor and expander stages.
Optimization of energy storage capacity using distributionally robust optimization for converter-based grids
Authors: Liu Jinjun , Han Minxiao , Tang Xiaojun , Sun Tiankui , Xie Wenqiang
Published: February 2024

As the penetration of converters into the grid continues to increase, converter-based power sources are replacing synchronous machine-based power sources, leading to the establishment of a converter-based grid (CBG) for regulating grid frequency and voltage. At this stage, energy storage becomes a necessity to support the operation of the CBG. The grid-interfacing inverters are transitioning from the conventional grid-following (GFL) control to the grid-forming (GFM) control. within the context of this research paper, considering the premise that energy storage capacity must meet CBG stability constraints and accommodate the integration of renewable energy sources, a capacity optimization model is constructed based on distributional robust optimization. The primary objective of this model is to minimize the overall cost with the allocation of energy storage capacity as the central focus. The study includes case analyses conducted within an IEEE-14 node CBG. The results of the case analyses confirm that the determined energy storage capacity can ensure the stable operation of the CBG and meet the demands for integrating renewable energy sources.
Flexible resource optimal allocation strategy for distribution system resilience improvement under failure uncertainty
Authors: Gu Jingda , Li Ying , Ju Li , Zuo Xianghong , Zhao Yuheng
Published: February 2024

Extreme disasters have led to huge economical losses to the power system and posed a huge threat to the stable supply of electric energy. Especially for traditional passive distribution network systems, failures of transmission lines, towers, and other equipment will cause large-scale power outages and huge economic losses. In order to improve the ability of the power system to deal with extreme weather disasters, this paper proposes an optimal configuration strategy for the distribution network backup power resource oriented to resilience improvement, considering the uncertainty of equipment failure caused by disasters in the case of a known disaster range. The location and capacity of backup resources can be properly configured to reduce the load shedding of the power distribution network during the disaster process, thereby improving the resilience of the distribution network. The method proposed in this paper is modeled as a two-stage stochastic programming, which includes mix-integer constraints. In the first stage, the optimization problem confirms the capacity and location of the flexible resources. In the second stage, the operational constraints and costs of load shedding are considered. The resilience enhancement method is verified on the improved IEEE-33 node system, and the result shows that the method proposed in this paper can effectively enhance the resilience of the urban power network.
Research on ultra-short-term load forecasting method based on PCA-MIC-LSTM
Authors: Pan Lianrong , Lv Jia , Li Peikai , Fu Yuan , Chen Xinling
Published: February 2024

This research presents a PCA-MIC-LSTM-based ultra-short-term electric load forecasting approach. This method uses Principal Component Analysis (PCA) technology to denoise power load data, uses the Maximal Information Coefficient (MIC) method to perform feature screening and correlation analysis on the processed data and finally selects some features with high correlation to input Long-Short-Term Memory Neural Network (LSTM) for training and modeling. Through actual case analysis, this method reduces the prediction error MAPE by 0.29% compared to the basic LSTM model. Compared with LightGBM, Xgboost, and SVR models, the prediction error MAPE is reduced by 0.16%, 0.11%, and 0.32%, respectively. It demonstrates the validity of the approach established in this investigation and provides technical support and a theoretical basis for scientific decision-making to optimize the precision of ultra-short-term electric load prediction in power systems.
Frequency regulation scheme for islanded microgrid
Authors: Shao Mingyan , Li Xiaolei , Li Chen , Zhang Hongzhe , Zhu Yu , Dong Xu , Xu Jiadong , Chen Bin
Published: February 2024

When the main grid of the power grid malfunctions undergoes emergency repairs, the microgrid is in off-grid operation. At this time, the microgrid in an isolated state must have self-frequency regulation capability. This article proposes a frequency control strategy for isolated microgrids, which can improve their ability to resist frequency interference. The proposed control strategy considers the different characteristics and capabilities of various micro-sources for frequency regulation. It classifies the frequency modulation micro-sources in the microgrid. Judgment conditions and parameters are set to determine whether each micro-source participates in frequency modulation and the participating components. The isolated microgrid has an economical and fast frequency modulation strategy. Finally, a microgrid simulation model is established using Matlab/Simulink simulation software to verify the effectiveness of the proposed frequency modulation strategy.
The influence of external conditions on the physical characteristics of Press-Pack IGBTs
Authors: Lu Yujia , Jiao Chaoqun
Published: February 2024

In order to solve the problem of unclear factors affecting the physical characteristics of Press-Pack IGBT devices, this paper explores the influence characteristics of the two main external conditions of fixture pressure and heat dissipation capacity on the physical parameters of Press-Pack IGBTs by building IGBT models with different chip structure layout considering various physical characteristics of materials. The results show that the effect of fixture pressure on the stress characteristics of the device is more obvious than the heat dissipation ability of the device, and the water-cooling heat flux has more influence on the electrical-thermal characteristics of the device. The research results provide a reference for the external conditions and structure selection of Press-Pack IGBTs.
Research and application of target detection algorithm for live operation in substation
Authors: Yang Fayu , Duan Xuejiao , Wang Jia , Wang Yueming , Zhang Hong-an
Published: February 2024

The substation is an important node connecting the backbone network and distribution network and is the core hub of the smart grid. With the continuous increase of electrical equipment, the substation plays a vital role in the whole power system. The structural principle of deep learning convolutional neural network is deeply studied, which lays a theoretical foundation for substation fault detection and recognition based on the object detection algorithm. This paper focuses on fault detection algorithms based on deep learning. First, two mainstream target detection algorithms, Faster R-CNN and YOLO V5, are applied to the self-made substation fault data set. The experimental comparison shows that while the YOLO V5 algorithm has a slightly higher recognition speed, the accuracy of fault target recognition and similar background image recognition is higher than that of the Faster R-CNN algorithm. Then, for the benchmark network YOLO V5, an improved method is proposed. The innovative idea is to delete large branches from the network detection part for the detection of small faults in the station, so as to reduce the number of model parameters and improve the speed of model detection.
Ultra-short term prediction of wind power based on multi-resolution closed-loop method
Authors: Zhang Yuhang , Liu Wenhao
Published: February 2024

In order to improve the accuracy and stability of wind power prediction, a multi-resolution closed-loop wind power ultra-short term prediction method is proposed. Using historical data with different resolutions, the differential data is generated by the pre-predictor with low, medium and high resolutions, and then the differential data is combined with the post-prediction data into the post-predictor with three resolutions for training. Since the differential data is obtained from the prediction data with different resolutions, the post-prediction data containing the differential data contains inconsistent information between different resolutions, so that the post-predictor receives the inconsistency between different resolutions and minimizes the inconsistency after several closed-loop iterations, and finally outputs wind power prediction with different resolutions. At the end of the paper, simulation experiments are carried out using the data of the 2022 KDD Cup competition, and comparison is made with some mainstream wind power prediction models. It is found that the proposed model has high accuracy and stability.
Convergence criterion of power flow calculation based on graph neural network
Authors: Li Shenhao , Pan Zhichon , Li Hongyi , Xiao Yue , Liu Ming , Wang Xiaorui
Published: February 2024

In order to solve the problem of current data-driven power flow calculation methods rarely consider the divergence of power flow, which always maps a false system power flow when a divergence power flow case was given, a data-driven power flow convergence method based on DGAT-GPPool graph neural network classifier is proposed. Firstly, to solve the problem that the classical graph convolution method does not consider the edge attribute, a double-view graph attention convolution layer is constructed based on line admittance. Secondly, to solve the existing pooling method also does not consider the edge attribute and the loss of physical meaning of the coarse graph obtained from pooling, a grid partition pooling layer is constructed based on the electrical distance between nodes. Finally, 10000 system samples containing different network topologies are generated based on the IEEE 14-node system and its extended system, the accuracy reaches 99.3% in the testing set after training, and the effectiveness of the improvements in graph convolution and graph pooling is verified by comparative experiments.
The simulation study of high-performance micro-inductors Based on MEMS 3D coils
Authors: Yi Cheng , Pi Xingyu , Chen Hongyu , Li Xinrong , Sun Xuecheng
Published: February 2024

With the development of flexible electronics and microsystems, the demand for the miniaturization of electronic components is becoming increasingly urgent. Due to the advantages of miniaturization, low power consumption, and easy integration, the micro-inductors fabricated by microfabrication technology get more and more attention. However, the traditional two-dimensional inductors are no longer able to meet the growing needs of today’s society in terms of occupied areas, inductance values, and packaging costs. So, this paper proposes a three-dimensional structure thin film solenoid micro-inductor based on MEMS and analyzes it by using finite element method (FEM). The simulation focuses on recording the inductance values and quality factors of the micro-inductors with varying parameters in the frequency range of 0-2, 000 MHz. Additionally, the maximum current values corresponding to the micro-inductors with different parameters are recorded at the operating temperature of polyimide, specifically addressing the current-carrying capacity. The simulation result has certain theoretical guidance for high-performance micro-inductors design.
High-frequency distortion phenomenon and solution of low frequency vibration sensor
Authors: Zhang Yuyang , Li Yiran , Han Rongxing , Bian Yanfeng
Published: February 2024

This paper analyzes the difference between several acceleration over-limit faults, and finds out the cause of false acceleration fault of wind turbines, which is because the low-frequency vibration sensor used by the unit is interfered with the high-frequency signal generated by the friction of the yaw system and causes the sensor output signal distortion. The performance of different manufacturers’ sensors under different installation positions is reproduced on the spot. A cost-effective solution to the high frequency distortion problem (installing a physical low-pass filter) is developed, and the comparative test results before and after its application are demonstrated experimentally.
Design and development of single-phase inverter for locomotives based on SVPWM
Authors: Liu Yang , Zeng Jie
Published: February 2024

For locomotive in high-power inverter power supply output efficiency is low, the level is not stable, push-pull circuit before the switch tube of high pressure, low utilization rate of the original winding transformer problem, designed and developed a kind of single phase inverter power supply based on SVPWM control. The inverter is designed with a modular structure with a rated power of 4KW, which is used to supply power to the cab electrical apparatus and auxiliary air compressor at both ends of the locomotive. It is composed of a filter circuit, a front-end boost control drive circuit, a full-bridge DC boost circuit, an inverter control circuit, a voltage and current sampling circuit, a back-end full-bridge inverter circuit and a protection circuit. The front stage of the inverter adopts a full bridge chopper circuit topology, while the rear stage achieves SVPWM control through the Vacon NXS control box. Finally, a power supply prototype was produced through simulation verification, and the results showed that the designed power supply met the design requirements.
The research on power quality management technology of station area based on distributed photovoltaic scale access
Authors: Gu Zhanlei , Zhao Zhiyuan , Dong Zhiyuan , Wang Jun
Published: February 2024

The intermittency, randomness and fluctuation of low voltage distributed photovoltaic power generation bring problems such as overvoltage, harmonic overlimit and reverse overload to rural distribution network, which seriously affect the power supply quality of low voltage distribution network. This paper mainly analyzes the power quality problems caused by large-scale distributed photovoltaic connected to rural distribution network, such as terminal overvoltage, transformer reverse overload, harmonic overlimit, and three phase unbalance. The power quality management strategy of low voltage station area based on distributed energy storage system is proposed, and the power quality management business module of low voltage station area is built based on the power information acquisition system to verify the reliability of the power quality management strategy of low voltage station area. The application effect of distributed energy storage system in controlling overvoltage, reverse overload and harmonic overlimit in low voltage station is verified through pilot construction.
Characterization of linear motor flux pump using H-formulation
Authors: Zhi Tengfei , Liu Shixian , Ren Ke , Wu Pengfei
Published: February 2024

H-formulation is an effective method for electromagnetic simulation analysis of superconductors. This paper innovatively uses H-formulation to simulate and analyze the operation characteristics of magnetic flux pump operating in linear-motor pattern. Via COMSOL Multiphysics, this paper establishes a two-dimensional electrical equipment simulation model that comprehensively compares excitation conditions of triangular and trapezoidal current waves to investigate the effects of the working excitation waveforms’ frequency and amplitude on the operating features of the equipment. The following operation control laws are revealed: the current amplitude has a linear control effect on the mean value of superconductor surface electric field and the average amount of air-slot density of magnetic flux, the current frequency has no effect on the air-gap magnetic field waveform, and the regulation effect of the excitation frequency on the average value of superconductor surface strength of electric field is related to the waveforms. Finally, the equivalent circuit of the pumping model is established, and two interrelated L-R equivalent circuits are designed by quadratic substitution, and the final pumping current reaches 43A.
Wind turbine gearbox temperature prediction based on improved whale optimized long short-term memory network
Authors: Liu Shu , Kong Deqiang , Wang Xuejie , Sun Zihan , Yi Likui
Published: February 2024

Aiming at the problem of low prediction accuracy of wind turbine gearbox temperature, the improved whale algorithm is used to optimize the long and short term memory network to predict the oil temperature of gearbox. The input data is based on the grey correlation degree to mine the parameters that are highly correlated with the oil temperature of the gear box, and the prediction model under healthy state is established. Finally, the experimental analysis shows that the method used in this paper has good accuracy in the oil temperature prediction of gearbox.
Research on accurate fire detection & early warning model for lithium-ion battery packs
Authors: Miao Handeyu
Published: February 2024

To improve the fire detection & early warning accuracy for lithium-ion battery packs and reduce false alarms and missing reports, the fire occurrence mechanism and cause factors of lithium-ion battery packs were analyzed, the calculation method of these characteristic parameters and basic judgment conditions of thermal runaway occurrence were explored, and then a thermal runaway-induced fire spread model of lithium-ion battery packs was established. Next, the scheme and model for accurate detection and early warning of lithium-ion battery pack fire was designed. Furthermore, an accurate fire detection & early warning model of “characteristic parameter sorting and screening + comprehensive conditional judgment + grading implementation” was proposed. Experimental results demonstrate that the accurate fire detection & early warning model for lithium-ion battery packs built in this study would be feasible.
An improved equalization circuit with bidirectional CUK converter for series-connected battery strings
Authors: Yi Qilin , Ling Rui , Wang Pan , Tong Zhaosheng
Published: February 2024

This paper proposed an improved equalization circuit based on a bidirectional CUK converter. Compared with traditional bus equalization circuits based on CUK converter, it owns a simpler structure with fewer inductors, resulting in a smaller volume and higher energy density of the proposed equalization circuit. The operation principle and steady-state characteristic of the equalizer are analysed. The equalizer is applied to the energy balance of the series-connected battery strings, and the balance principle is designed. The proposed equalization system achieves a fast energy balance of the battery pack. Simulation results verify the effectiveness of the designed equalization circuit and balance strategy.
Study on the minimum polarity distance of suspension tower for UHVDV transmission line in ultrahigh altitude area
Authors: Mao Qiang , Guo Kai , Bai Xiaolu , Ma Xianghui , Liu Sining , Wang Nan
Published: February 2024

The design experience of ± 800 kV UHVDC transmission line in 3500 m and above is less. Based on the basic design conditions of ± 800 kV DC transmission line project, the minimum polarity distance of the suspension tower in an ultrahigh altitude area is investigated and the effects of the electromagnetic environment, insulator string length, V-string angle string and air gap on polarity distance are analyzed. Finally, the minimum polarity distance of the suspension towers under different altitudes, V-string angle string and icing area conditions are calculated, which provides technical support for the tower design of UHVDC transmission lines in ultrahigh altitude areas.
Improved study on double closed-loop control of three-phase PWM rectifier based on induction heating rectifier side
Authors: Zheng Duo , Guo Quanli
Published: February 2024

With the development of power electronics technology, induction heating power supply becomes more applicable. The three-phase PWM rectifier is widely used in induction heating system because of its advantages of better power factor and bi-directional energy transfer, and often adopts the control method of voltage outer loop and current inner loop to improve its control performance. However, the traditional rectifier control structure in the application process will appear such as poor anti-interference ability, low fault tolerance and other outstanding problems. In this paper, an improved H∞ controller is designed for the induction heating system based on the rectifier-side power regulation by combining the robust control principle, establishing a state space model of the system with an equivalent series resonant load, firstly decoupling the linearization of the model, and then designing a double-closed-loop PI controller as well as an improved current inner-loop H∞ controller based on the decoupled model. In order to facilitate the analysis, the PI controller and the H∞ controller are simulated under two kinds of starting conditions, and the comparison further confirms that the improved system has better anti-interference ability and dynamic characteristics.
Heat transfer performance study of a separated pulsating heat pipe
Authors: Liang Chenglin , Su Lei
Published: February 2024

In order to study the heat transfer performance of the pulsating heat pipe (PHP) under the separation arrangement of evaporating and condensing ends, this paper designs a separated PHP for experimental investigation, and describes its heat transfer capability in terms of the wall temperature oscillation performance, the heat transfer temperature difference and the heat transfer thermal resistance. Under different heating powers, the effects of different placement inclinations and their structures on the heat transfer performance of the in-line and bent separated PHP are analyzed. The study shows that in the low heat transfer power scenario, the performance of the in-line type separated PHP is more excellent, and with the increase of the placement of the inclination of the heat transfer situation is further optimized, 90 ° placement of the inclination of the optimal performance of the heat transfer; bent type separated PHP condensing end of a certain level of inclination is conducive to low-power startup and operation, the condensing section of the 15 ° horizontal angle of the optimal performance; and in the high heat transfer power, the two performances are similar, but the arrangement of flexible bent type separated PHP is more suitable for the changing heat transfer scenarios.
Modelling and fault analysis of APROS-based moisture separation reheater
Authors: Lu Chunbin , Xing Tianyang , Zhu Xiaoliang , Xu Jianqun
Published: February 2024

A modular modelling approach was adopted to build a dynamic simulation model of the moisture separation reheater on a high-precision APROS real-time platform to investigate the dynamic operating characteristics of the moisture separation reheater. The model was subjected to steady-state and step dynamic tests at different loads. The results show that the established model can correctly reflect the steam flow and heat transfer properties and can meet the requirements of the simulation. Using the one-dimensional distribution of the model, the effect of a small breakage failure in the heat exchanger bundle was further investigated. The results showed that the heat transfer tube bundle had leaks, reducing the heat transfer capacity and affecting the quality of the steam used to work in the low-pressure turbine. Simultaneously, the effect on steam outlet parameters increased with the degree of leakage in the heat exchanger.
A remote self-calibration design for three-phase power monitoring terminal
Authors: Wei Yue , Gao Peizhong , Qin Ziming , Wei Hongyi , Liu Yongqian , Li Shibo
Published: February 2024

In view of the situation that the existing three-phase power metering device is prone to excessive error and inaccurate measurement during long-term operation, and the device must be removed for re-calibration, a self-calibration power monitoring terminal based on NB-IOT communication is proposed. The power monitoring terminal adopts an external voltage transformer and current transformer, and the input signal is mV and mA level AC small signal. The integrated design of single-chip microcomputer and metering chip is used in the power monitoring terminal. The single-chip microcomputer reads and writes the data collected by the metering chip and displays and transmits the power data. After the remote measurement instruction is issued, the three-phase sinusoidal signal generator chip inside the system is used to simulate the voltage signal and current model, and the external voltage and current input channel are switched with the analog signal channel through the analog switch to complete the internal self-verification work of the device. This scheme can significantly reduce the workload caused by dismantling, installing and verifying the instrument, ensure the measurement accuracy of the instrument for a long time, and has great practical value.
Monitoring and evaluation of the status of Motor-Operated Valves in nuclear power plants
Authors: Zhang Yunhui , Zhang Yilin , Wang Ping , Liu Bo , Wang Gang
Published: February 2024

To address the inability to monitor the performance status of Motor-Operated Valves (MOV) during the operation of nuclear power plants, develop the MOV status evaluation model and design a valve online monitoring system. During valve operation, the data acquisition unit (DAU) installed in the distribution cabinet of the motor control center (MCC) can capture the voltage, current and switch signals. On the basis of the aforementioned parameters, the active power curve and characteristic points of the valve can be determined, implemented monitoring and evaluation of the status and performance of MOV.
Partial discharge fault detection method of switchgear based on signal aliasing spectrum separation model
Authors: Zhao Haoran , Zhang Muyong , Zhu Xinggang , Lu Zhiyong , Jiang Ming , Liu Lishi
Published: February 2024

At present, the detection nodes of partial discharge fault in switchgear are generally set in one direction, and the fault detection range is small, which leads to an increase in the false recognition rate of partial discharge fault detection. Therefore, the design and verification analysis of the detection method of partial discharge fault in switchgear is proposed. According to the current measurement requirements and standards, firstly, the characteristics of switchgear discharge faults are extracted, and the fault detection range is expanded by the multi-step method. Multi-step partial discharge fault detection nodes are deployed, and the partial discharge fault detection model with signal aliasing and spectrum separation is constructed. The fault detection is completed by hierarchical fuzzy automatic identification. The test results show that the final detection error rate of partial discharge fault is well controlled below 20% by comparing the seven selected test cycles and combining the signal aliasing spectrum separation model, which shows that the designed detection method of partial discharge fault is more flexible and changeable, and has strong pertinence and reliability. Facing the complex switchgear operating environment, it can also mark the fault position in the shortest time, strengthen the detection results and ensure the detection accuracy.
Pilot protection based on novel comprehensive impedance of positive sequence fault component for distribution network
Authors: Wang Yabing , Wang Hongbin , Tong Xiaoyang , Zhao Zibin , Dong Xingxing
Published: February 2024

The integration of distributed power sources into the distribution network has changed the topology of traditional distribution networks, resulting in changes in fault characteristics, and brought severe challenges to conventional current protection of distribution network. This article proposes a protection method based on the comprehensive impedance of a new positive sequence fault component. Analyze the fault characteristics of positive sequence fault voltage and current during faults inside and outside the line area connected to different types of distributed power sources. The positive sequence fault components of voltage and current at both ends of the section are used to calculate the estimated line impedances. A novel comprehensive impedance is obtained by their subtraction. The ratio of comprehensive impedance to line impedance is constructed. The protection criterion for short circuit fault is given. The simulation experiments illustrate the effectiveness of proposed protection algorithm, not affected by the fault types, locations, permeabilities of distributed generations, has strong ability to withstand transition resistance.
Research on risk prediction algorithm for operation and maintenance data based on grey theory
Authors: Du Xuguang , Zhang Heyi , Zhu Chunyan , Zhong Wen , Fan Yonggang
Published: February 2024

This paper proposes a risk prediction algorithm for power operation and maintenance data networks based on the grey theory, aiming at the real-time, healthy, and high stability requirements of power operation and maintenance data networks in work. By combining the entropy weight method to assign weight to risk indicators, the risk prediction of data networks in dynamic networks is achieved. By using two indicators of risk value and risk dispersion, the overall system is predicted for risk. Through experimental comparison, the prediction algorithm based on grey theory designed in this paper has a smaller error than existing prediction methods, which more scientifically realizes the risk prediction mechanism, ensures the stability of power operation and maintenance data, and ensures the reliable operation of the power grid.
Detection performance of arcing fault detectors in the Chinese market according to the Chinese Standard GB/T 31143
Authors: Huang Zhanhua , Jia Chuanzhen , Li Zhe , Du Yaping , Cheng Qingsha S. , Du Hao , Li Xiao
Published: February 2024

There are two sets of standards available in the Chinese market that specify the design requirements and operating tests for arc fault detection devices (GB/T 31143) and arcing fault detectors (GB 14287.4) respectively. While arcing fault detectors (AFDs) are claimed to have passed GB 14287.4 standard tests, it remains unclear whether these AFDs can pass GB/T 31143 standards and effectively detect arc fault signals. This study experiments to explore the operational performance of AFDs in the Chinese market based on GB/T 31143 standards, revealing that not all AFDs can pass this test and provide adequate protection for people’s lives and property. The main reason for the failure is that the arcing characteristics, such as flat shoulders and reduced amplitude, of the signal are easily masked by other branch circuit loads.
Accelerating inverter control system testing and verification based on FPGA
Authors: Zhu Huilin , Zhang Yongming , Chen Guochu
Published: February 2024

Traditional FPGA development faces challenges such as long development cycles and high development difficulty. However, the method proposed in this paper overcomes these issues, improves FPGA development efficiency, reduces development costs, and provides designers with greater flexibility. Based on the model of an inverter control algorithm, this paper utilizes MATLAB software and employs Simulink’s embedded coder HDL Coder to automatically generate code from the model. Additionally, leveraging the FPGA-in-the-loop tool, a connection between the FPGA and the external simulation environment Simulink is established, enabling combined simulation of MATLAB and FPGA to accelerate the design and verification of the inverter control algorithm.
1D simulation analysis and optimization design of engine cooling system
Authors: Zhao Hongxia , Li Xian , Fu Yiwei , Xing Xiangpeng
Published: February 2024

The engine cooling system takes away the heat absorbed by high-temperature parts during the operation of the car engine in a timely manner, keeping it working within the normal temperature range. This article applies Flowmaster software to establish a one-dimensional cooling system model for a certain model of National Five diesel engine. Relevant boundary conditions are inputted to complete steady-state simulation calculations of the system under different operating conditions, obtaining the flow rate, pressure distribution, and temperature rise of each component. At the same time, three optimization schemes are designed based on the original cooling system to predict and evaluate the working capacity of the cooling system, Based on the calculation and analysis results, improvement suggestions are proposed to guide the structural design and testing of the cooling system, greatly reducing research and development time and reducing research and development costs. The calculation results show that the flow rate of each component in the rated point, heating test condition, and idle condition of the original plan has decreased compared to the flow rate of a certain four machine on the same platform under the same working condition (the air compressor flow rate is higher than the limit value), and the temperature difference of the radiator and heating flow rate do not meet the specification requirements. Suggest using Plan 3 to increase the water pump speed ratio to 1.25, with a warm air flow rate of 5.33L/min under idle conditions, which is 72% higher than the original plan and meets the vehicle limit requirements. In addition, to ensure the accuracy and reliability of the model and calculations, this project conducted cooling system tests on an engine bench. The comparison between the simulation calculation data and the experimental data showed that the simulation calculation results were consistent with the experimental results.
Research on vibration response of 550 kV GIL isolation compensation unit against earthquake loading
Authors: Tian Zhiren , Gong Junqiang , Zhang Lin , Zhang Xin , Chen Zhiqiang , Huang Ruodong , Xiong Jiaming
Published: February 2024

To analyze the vibration response of Gas Insulated Transmission Lines (GIL) of urban power grid under different seismic intensity levels, based on the actual structure of the standard isolation compensation unit (isolation unit and compensation unit) of 550kV GIL, A fine 3D model of isolation compensation unit segment of 550 kV GIL was established, and the actual vibration response of each standard unit segment of GIL under different seismic conditions was studied by response spectrum analysis. This study clarified the action mechanism and law of GIL vibration characteristics under seismic conditions of urban power grids, provided the relative support for the research of shock absorption of GIL, and was great significance to the actual project of GIL.
The optimization, design and performance of the FBCM23 ASIC for the upgraded CMS beam monitoring system
Authors: Kaplon Jan , Wegrzyn Grzegorz , Shibin Konstantin , Barendregt Marnix
Published: February 2024

We present the development of the FBCM23 ASIC designed for the Phase-II upgrade of the
Fast Beam Condition Monitoring (FBCM) system built at the CMS experiment which will replace the
present luminometer based on the BCM1F ASIC [1]. The FBCM system should
provide reliable luminosity measurement with 1 ns time resolution enabling the detection of
beam-induced background. The FBCM23 ASIC comprises 6 channels of the fast front-end amplifier
working in transimpedance configuration, booster amplifier, and leading edge
discriminator. The complete processing chain provides an overall shaping function equivalent to
the CR-RC3 filter. The paper will show the optimization of the design, overall
architecture, and the detailed implementation in a CMOS 65 nm process as well as preliminary
electrical performance.
CMS Outer Tracker Phase-2 Upgrade on-module powering
Authors: Zografos A. , Blanchot G. , Kovacs M. , Mateos I. , Schleidweiler K. , Szydlik P. ,   the CMS Tracker collaboration
Published: February 2024

The CMS Tracker Phase 2 Upgrade for the High Luminosity Large Hadron Collider will use two module types, which contain different sensor configurations and custom ASICs. Guaranteeing the power integrity of all modules for the full lifetime of the detector is crucial for the detector performance. This article describes the historical evolution of the powering architecture, the problems encountered, and the solutions implemented for the two types of modules, as well as the final on-module powering strategy along with the data and modelling that motivated it.
Observed links between heatwaves and wildfires across Northern high latitudes
Authors: Hegedűs D , Ballinger A P , Hegerl G C
Published: February 2024

Data on Arctic and Sub-Arctic summer heat events are limited due to the sparse network of surface observation stations. Here, we analyze large heat events within 60°–80°N using land surface temperature (LST) observations from the moderate resolution imaging spectroradiometer (MODIS) sensor aboard the Terra satellite. Our heatwave (HW) detection method uses exceedances of the climatological 90th percentile of LST across summer months, and a spatio-temporal density-based clustering algorithm to distinguish space-time coherent events across Northern Hemispheric high latitudes for the summers of 2000–2022. We find a close link between HW duration, spatial extent and amplitude across the study region (correlations ranging from 0.63 to 0.73). MODIS-derived burned area data show that wildfire seasons are significantly correlated to summer HW activity, particularly in Siberia (r = 0.87 at p < 0.05) and Alaska and NW Canada (r = 0.45 at p < 0.05), and are also spatially co-located. MODIS active fire data also show substantial increase during larger heat events. For the strongest HWs in Siberia, the peak in daily fire count (from the MODIS active fire archive) lags behind peak HW activity. We conclude that there is a close link between intense fire summers and extensive HWs over boreal and shrub tundra regions (Interior Alaska, the Canadian Prairies and Eastern Siberia).
Corrugated Structural Metal Decking System under Tensile Strength Test
Authors: Chong Weng Khuen , Wong Jing Ying , Yip Chun-Chieh , Goh Yann Ling , Sanzana Mirza Rayana
Published: February 2024

Corrugated metal decking has been widely used in the construction industry for many years due to its benefits towards the sustainability, improve time performance of the projects and environmental aspects. This article includes the investigation of tensile strength and identify the failure behaviour of different corrugated surface profile of the metal decking that innovated for structural slab. Novelty of this research is the discovery of the tensile performance of a cold rolled corrugated metal decking profiles at various points of interest for a composite flooring system. Tensile strength specimen preparation complies with the ASTM E8 Standard. A total of 60 specimens with different thicknesses and different parts of metal deck have been tested by the universal testing machine (UTM). The findings on how Base Metal Thickness (BMT) affects the tensile strength and the unique roll formed of the corrugated metal decking system, with 0.75BMT & 1.00BMT, are discussed and analysed in this article. Results showed that the average tensile strength value for 0.75BMT and 1.00BMT from part A was 592.47MPa and 554.41MPa, respectively, and the metal decking is up to the designed strength and the unique roll forming embossment provides better bonding quality between concrete and steel to be used in the industry.
Carbonation of Shale Ceramsite High-Strength Lightweight Concrete Incorporating Graphene Oxide
Authors: Hong Xiaojiang , Lee Jin Chai , Chu May Yen , Li Lin , Zhou Zhengjie
Published: February 2024

The growing demand of concrete for improving durability has stimulated extensive research on graphene oxide (GO). Carbonization, as an irreversible deterioration, should be paid more attention to high-strength lightweight concrete (HSLWC) with the characteristics of porous structure. In this study, the effect of different low content of GO on the carbonation depth of HSLWC made from shale ceramsite was experimentally investigated. Subsequently, the effect of GO on pore distribution of HSLWC was analyzed. Four groups of grade 60 HSLWC were designed for comparative experiments, in which 0.00%, 0.01%, 0.03% and 0.05% (by weight of cement) GO were added, respectively. The results indicated that GO could effectively reduce the carbonization depth of HSLWC. When GO content was 0.05%, the carbonization depth was reduced by approximately 23%. The main reason was that GO not only reduce the total porosity but also refine the pores, thus improving the carbonization resistance of HSLWC.