Power system operation and control are based on power flow calculations. In order to solve the uncertainty of the increasing penetration of renewable energy, the voltage fluctuation at the load point increases in the distribution network, and the inaccuracy of the power flow calculation due to the insufficient power flow data collection capability of the traditional power system. In this paper, a data‐driven power flow analysis model is proposed, a back propagation neural network combined with genetic algorithm (GA) and adaptive moment estimation (ADAM) optimization algorithm model is constructed to analyze the power flow calculation method of distribution networks under stochasticity. Firstly, the power flow initial value information, topology characteristics, and power factor index are introduced to construct a training set, and the mapping relationship between bus voltage and power is fully explored by training the regression model. Second, the GA‐ADAM algorithm is used to optimize the initial values and weight parameters of the model. Finally, it is verified based on IEEE‐33 bus distribution model, and the model is used for power flow calculation, and compared with other methods through each relevant error evaluation indicators. The results show that the model constructed in this paper has small error indicators and high accuracy, which improves the efficiency and accuracy of power flow calculation.
{"title":"Distribution network power flow calculation based on the BPNN optimized by GA‐ADAM","authors":"Huijia Liu, Ling Feng, Yi Wu, Jie Teng, Dong Xiao","doi":"10.1049/tje2.12330","DOIUrl":"https://doi.org/10.1049/tje2.12330","url":null,"abstract":"Power system operation and control are based on power flow calculations. In order to solve the uncertainty of the increasing penetration of renewable energy, the voltage fluctuation at the load point increases in the distribution network, and the inaccuracy of the power flow calculation due to the insufficient power flow data collection capability of the traditional power system. In this paper, a data‐driven power flow analysis model is proposed, a back propagation neural network combined with genetic algorithm (GA) and adaptive moment estimation (ADAM) optimization algorithm model is constructed to analyze the power flow calculation method of distribution networks under stochasticity. Firstly, the power flow initial value information, topology characteristics, and power factor index are introduced to construct a training set, and the mapping relationship between bus voltage and power is fully explored by training the regression model. Second, the GA‐ADAM algorithm is used to optimize the initial values and weight parameters of the model. Finally, it is verified based on IEEE‐33 bus distribution model, and the model is used for power flow calculation, and compared with other methods through each relevant error evaluation indicators. The results show that the model constructed in this paper has small error indicators and high accuracy, which improves the efficiency and accuracy of power flow calculation.","PeriodicalId":22858,"journal":{"name":"The Journal of Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138988579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
To replace the manual labour involved in pipe dredging, this study proposes an extensible differential‐speed helical drive pipe dredging robot. The robot can be released in an inspection well to remove silt from a sewer pipe for routine maintenance. This robot consists of a differential drive system, an extensible helical drive element, a dredging plate, and a retractable feed screw. The extensible helical drive element is used to address the problem of diameter differences between the inspection well, sewage well, and drainpipe. The problem of dynamical dredging working conditions is studied by a detailed design of mechanical system. To analyze the operational process of the proposed robot, a virtual prototype is established using the ADAMS software. The simulation results show that the proposed robot can achieve the slurry‐flow operating state because of its reasonable structure and cutting, mixing, and conveying silt functions. The result presented in this study can help to improve energy efficiency and provide technical assistance for same type robots.
{"title":"Design and analysis of extensible differential‐speed helical drive pipe dredging robot","authors":"Fei Lou, Jing Guan, Wensai Lu","doi":"10.1049/tje2.12342","DOIUrl":"https://doi.org/10.1049/tje2.12342","url":null,"abstract":"To replace the manual labour involved in pipe dredging, this study proposes an extensible differential‐speed helical drive pipe dredging robot. The robot can be released in an inspection well to remove silt from a sewer pipe for routine maintenance. This robot consists of a differential drive system, an extensible helical drive element, a dredging plate, and a retractable feed screw. The extensible helical drive element is used to address the problem of diameter differences between the inspection well, sewage well, and drainpipe. The problem of dynamical dredging working conditions is studied by a detailed design of mechanical system. To analyze the operational process of the proposed robot, a virtual prototype is established using the ADAMS software. The simulation results show that the proposed robot can achieve the slurry‐flow operating state because of its reasonable structure and cutting, mixing, and conveying silt functions. The result presented in this study can help to improve energy efficiency and provide technical assistance for same type robots.","PeriodicalId":22858,"journal":{"name":"The Journal of Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139020012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shuhao Zhang, Yunhua Luo, Zijian Wang, Hao Sun, Xiaoyi Wang
For high‐resolution radar, traditional direction of arrival (DOA) angle measuring algorithms for point‐like targets cannot be directly applied to extended targets. Instead, pixel‐based detection and clustering must be performed first, followed by angle estimation. However, the presence of factors such as clutter and system noise makes it impossible to guarantee a one‐to‐one correspondence between the multiple scattering points of an extended target and the real target, which may result in significant discrepancies between the angle estimation and localization results and the real target. To address this issue, this paper proposes and discusses a radar extended target arrival angle estimation method based on effective phase clustering. The proposed method selects effective target scatterers through the interferometric phase information between channels, clusters these points, and then estimates the DOA angle of the extended target, effectively reducing the impact of interference scatterers on DOA angle estimation and improving the angular measurement accuracy. The effectiveness of the proposed method was validated by the measured data obtained from an airborne digital beamforming radar system.
对于高分辨率雷达，传统的点状目标到达方向（DOA）角度测量算法无法直接应用于扩展目标。相反，必须先进行基于像素的检测和聚类，然后再进行角度估计。然而，由于杂波和系统噪声等因素的存在，无法保证扩展目标的多个散射点与真实目标之间的一一对应关系，这可能会导致角度估计和定位结果与真实目标之间存在很大差异。针对这一问题，本文提出并讨论了一种基于有效相位聚类的雷达扩展目标到达角估计方法。该方法通过信道间的干涉相位信息选择有效的目标散射体，对这些点进行聚类，然后估计扩展目标的 DOA 角，有效降低了干扰散射体对 DOA 角估计的影响，提高了角度测量精度。通过机载数字波束成形雷达系统获得的测量数据验证了所提方法的有效性。
{"title":"A radar extended target angle estimation method based on effective phase clustering","authors":"Shuhao Zhang, Yunhua Luo, Zijian Wang, Hao Sun, Xiaoyi Wang","doi":"10.1049/tje2.12343","DOIUrl":"https://doi.org/10.1049/tje2.12343","url":null,"abstract":"For high‐resolution radar, traditional direction of arrival (DOA) angle measuring algorithms for point‐like targets cannot be directly applied to extended targets. Instead, pixel‐based detection and clustering must be performed first, followed by angle estimation. However, the presence of factors such as clutter and system noise makes it impossible to guarantee a one‐to‐one correspondence between the multiple scattering points of an extended target and the real target, which may result in significant discrepancies between the angle estimation and localization results and the real target. To address this issue, this paper proposes and discusses a radar extended target arrival angle estimation method based on effective phase clustering. The proposed method selects effective target scatterers through the interferometric phase information between channels, clusters these points, and then estimates the DOA angle of the extended target, effectively reducing the impact of interference scatterers on DOA angle estimation and improving the angular measurement accuracy. The effectiveness of the proposed method was validated by the measured data obtained from an airborne digital beamforming radar system.","PeriodicalId":22858,"journal":{"name":"The Journal of Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138989731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Path planning is a crucial component for ensuring the safety and efficiency of flight missions, especially for fighter aircraft. To enhance the combat effectiveness of fighter aircraft, it is important to consider how to avoid danger sources an terrain obstacles, reduce fuel consumption, and utilize the aircraft's own performance to accomplish the mission objectives. In the modern battlefield environment, the shortest path is not the only criterion for planning, but also other factors such as the threat level to the aircraft, fuel consumption, mission completion time, and minimum turning radius. In this paper, the authors propose a multi‐constraint path planning method for fighter aircraft that incorporates these factors into an improved particle swarm algorithm. The authors transform the constraints of three‐dimensional terrain, threat source, fuel consumption, and mission time into an aggregated fitness function. The authors construct a limit curvature matrix to evaluate the feasibility of the generated path. The authors also introduce an adaptive adjustment strategy based on the activation function for the parameters in the particle swarm algorithm. The weights of each constraint are determined according to the actual demand. The experiment results show that the authors’ method can efficiently plan the optimal path that satisfies the requirements. Compared with other improved particle swarm algorithms, the authors’ method has higher optimal search efficiency and better convergence effect. The authors also provide optimal values for important parameters such as mission energy consumption, mission time, flight speed and others to support the overall mission planning. The authors’ method has a certain practical application value.
{"title":"3D path planning problem for fighter aircraft with multiple constraints","authors":"Ping Yang, Bing Xiao, Xin Chen, LiangLiang Guo","doi":"10.1049/tje2.12325","DOIUrl":"https://doi.org/10.1049/tje2.12325","url":null,"abstract":"Abstract Path planning is a crucial component for ensuring the safety and efficiency of flight missions, especially for fighter aircraft. To enhance the combat effectiveness of fighter aircraft, it is important to consider how to avoid danger sources an terrain obstacles, reduce fuel consumption, and utilize the aircraft's own performance to accomplish the mission objectives. In the modern battlefield environment, the shortest path is not the only criterion for planning, but also other factors such as the threat level to the aircraft, fuel consumption, mission completion time, and minimum turning radius. In this paper, the authors propose a multi‐constraint path planning method for fighter aircraft that incorporates these factors into an improved particle swarm algorithm. The authors transform the constraints of three‐dimensional terrain, threat source, fuel consumption, and mission time into an aggregated fitness function. The authors construct a limit curvature matrix to evaluate the feasibility of the generated path. The authors also introduce an adaptive adjustment strategy based on the activation function for the parameters in the particle swarm algorithm. The weights of each constraint are determined according to the actual demand. The experiment results show that the authors’ method can efficiently plan the optimal path that satisfies the requirements. Compared with other improved particle swarm algorithms, the authors’ method has higher optimal search efficiency and better convergence effect. The authors also provide optimal values for important parameters such as mission energy consumption, mission time, flight speed and others to support the overall mission planning. The authors’ method has a certain practical application value.","PeriodicalId":22858,"journal":{"name":"The Journal of Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135455013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract To enhance the utilization of renewable energy and the economic efficiency of energy system's planning and operation, this study proposes a hybrid optimization configuration method for battery/pumped hydro energy storage considering battery‐lifespan attenuation in the regionally integrated energy system (RIES). Moreover, a two‐layer optimization model was established for integrated energy system planning and operation based on the combination of the Salp Swarm algorithm and mixed‐integer linear programming. Considering wind and solar energies and multiple loads, such as electricity, cooling, and heating, the first step in this paper involved the construction of a model for the RIES incorporating hybrid energy storage and various energy‐conversion devices. Then, given a synergy among different energy sources in the system, the long‐term impact of battery‐lifespan attenuation is introduced by including battery‐replacement costs. Based on the optimization results obtained from daily operations, a hybrid energy storage‐based optimization configuration model is established to minimize the annual operational and energy‐storage investment costs. The results show that, compared to the systems with a single pumped hydro storage or battery energy storage, the system with the hybrid energy storage reduces the total system cost by 0.33% and 0.88%, respectively. Additionally, the validity of the proposed method in enhancing the economic efficiency of system planning and operation is confirmed. Furthermore, a comparative analysis is conducted of the impact of battery‐lifespan degradation on the system's economic efficiency. The results show that during the system's operation phase, the total system cost is reduced by 9.97% considering battery‐lifespan degradation than that without considering the degradation.
{"title":"Hybrid energy storage for the optimized configuration of integrated energy system considering battery‐life attenuation","authors":"Xianqiang Zeng, Peng Xiao, Yun Zhou, Hengjie Li","doi":"10.1049/tje2.12331","DOIUrl":"https://doi.org/10.1049/tje2.12331","url":null,"abstract":"Abstract To enhance the utilization of renewable energy and the economic efficiency of energy system's planning and operation, this study proposes a hybrid optimization configuration method for battery/pumped hydro energy storage considering battery‐lifespan attenuation in the regionally integrated energy system (RIES). Moreover, a two‐layer optimization model was established for integrated energy system planning and operation based on the combination of the Salp Swarm algorithm and mixed‐integer linear programming. Considering wind and solar energies and multiple loads, such as electricity, cooling, and heating, the first step in this paper involved the construction of a model for the RIES incorporating hybrid energy storage and various energy‐conversion devices. Then, given a synergy among different energy sources in the system, the long‐term impact of battery‐lifespan attenuation is introduced by including battery‐replacement costs. Based on the optimization results obtained from daily operations, a hybrid energy storage‐based optimization configuration model is established to minimize the annual operational and energy‐storage investment costs. The results show that, compared to the systems with a single pumped hydro storage or battery energy storage, the system with the hybrid energy storage reduces the total system cost by 0.33% and 0.88%, respectively. Additionally, the validity of the proposed method in enhancing the economic efficiency of system planning and operation is confirmed. Furthermore, a comparative analysis is conducted of the impact of battery‐lifespan degradation on the system's economic efficiency. The results show that during the system's operation phase, the total system cost is reduced by 9.97% considering battery‐lifespan degradation than that without considering the degradation.","PeriodicalId":22858,"journal":{"name":"The Journal of Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135714708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The system outage probability of two‐way hybrid satellite‐terrestrial relaying networks with hardware impairments is investigated, using a novel method which features appropriate signal‐to‐noise‐and‐distortion ratio expression adjustment. A concise closed‐form lower bound expression is derived, which is in good agreement with the exact outage probability in all signal‐to‐noise ratio regions. Based on the tight bound, an asymptotic expression is obtained, revealing that the hardware impairments coin the system outage probability ceiling. The deducing method, characterized by generality, can be applicable to various realistic fading channels. Simulation results validate the derived expressions.
{"title":"Outage probability of two‐way hybrid satellite‐terrestrial relaying networks with hardware impairments","authors":"Jingjing Shi, Tong Mu, Xiaofeng Tao","doi":"10.1049/tje2.12328","DOIUrl":"https://doi.org/10.1049/tje2.12328","url":null,"abstract":"The system outage probability of two‐way hybrid satellite‐terrestrial relaying networks with hardware impairments is investigated, using a novel method which features appropriate signal‐to‐noise‐and‐distortion ratio expression adjustment. A concise closed‐form lower bound expression is derived, which is in good agreement with the exact outage probability in all signal‐to‐noise ratio regions. Based on the tight bound, an asymptotic expression is obtained, revealing that the hardware impairments coin the system outage probability ceiling. The deducing method, characterized by generality, can be applicable to various realistic fading channels. Simulation results validate the derived expressions.","PeriodicalId":22858,"journal":{"name":"The Journal of Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139296288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sara Abdallaoui, Halima Ikaouassen, A. Kribèche, Ahmed Chaibet, E. Aglzim
This abstract discusses the significant progress made in autonomous vehicles, focusing on decision‐making systems and control algorithms. It explores recent advances, challenges, and contributions in the field, emphasizing the need for precise navigation and control. The paper covers various methodologies, including rule‐based methods, machine learning, deep learning, probabilistic approaches, and hybrid approaches, examining their applications and effectiveness in ensuring safe navigation. Additionally, it reviews ongoing research efforts, emerging trends, and persistent challenges related to decision‐making and manoeuvre execution in autonomous vehicles, addressing complex topics such as sensor measurement uncertainty, dynamic environment modelling, real‐time responsiveness, and safe interactions with other road users. The objective is to provide a comprehensive overview of the state of the art in autonomous vehicle navigation and control for readers.
{"title":"Advancing autonomous vehicle control systems: An in‐depth overview of decision‐making and manoeuvre execution state of the art","authors":"Sara Abdallaoui, Halima Ikaouassen, A. Kribèche, Ahmed Chaibet, E. Aglzim","doi":"10.1049/tje2.12333","DOIUrl":"https://doi.org/10.1049/tje2.12333","url":null,"abstract":"This abstract discusses the significant progress made in autonomous vehicles, focusing on decision‐making systems and control algorithms. It explores recent advances, challenges, and contributions in the field, emphasizing the need for precise navigation and control. The paper covers various methodologies, including rule‐based methods, machine learning, deep learning, probabilistic approaches, and hybrid approaches, examining their applications and effectiveness in ensuring safe navigation. Additionally, it reviews ongoing research efforts, emerging trends, and persistent challenges related to decision‐making and manoeuvre execution in autonomous vehicles, addressing complex topics such as sensor measurement uncertainty, dynamic environment modelling, real‐time responsiveness, and safe interactions with other road users. The objective is to provide a comprehensive overview of the state of the art in autonomous vehicle navigation and control for readers.","PeriodicalId":22858,"journal":{"name":"The Journal of Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139300564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Measuring the heartbeat and respiration of animals continuously can provide valuable information about their health status. Respiratory‐related diseases are very common in the poultry industry and unfortunately, there is no non‐contact respiratory monitoring system for measuring the breathing rate and heart rate of the broiler chicken. In this letter, the authors explored and tested the feasibility of utilizing a 24‐GHz continuous‐wave (CW) radar module for monitoring the vital signs (breathing rate and heart rate) of broiler chickens. A signal processing approach has been developed to extract vital signs of broiler chicken from Radar‐captured signals. The experiment was carried out on three different normal broiler chickens with the ages of 25–30 days, weight 1.18–1.6 kg where a 24‐GHz radar module was mounted at a distance of 0.2 m above the chest surface of the chicken, and this particular experiment was repeated for 20 times. The authors also used a reference ECG module (Biopac System) for extracting the breathing rate and heart rate of the broiler chicken and compared the accuracy of their proposed system. Experimental results demonstrated that the radar measurement closely matches the Biopac ECG acquisition module measurement and showed an accuracy of 96% for a short‐scale study.
{"title":"Non‐contact vital signs monitoring in broiler chickens","authors":"Md. Shafkat Hossain, Sourav Kumar Pramanik, Atikur Rahman, Shahin Ali, Shekh Md Mahmudul Islam","doi":"10.1049/tje2.12320","DOIUrl":"https://doi.org/10.1049/tje2.12320","url":null,"abstract":"Abstract Measuring the heartbeat and respiration of animals continuously can provide valuable information about their health status. Respiratory‐related diseases are very common in the poultry industry and unfortunately, there is no non‐contact respiratory monitoring system for measuring the breathing rate and heart rate of the broiler chicken. In this letter, the authors explored and tested the feasibility of utilizing a 24‐GHz continuous‐wave (CW) radar module for monitoring the vital signs (breathing rate and heart rate) of broiler chickens. A signal processing approach has been developed to extract vital signs of broiler chicken from Radar‐captured signals. The experiment was carried out on three different normal broiler chickens with the ages of 25–30 days, weight 1.18–1.6 kg where a 24‐GHz radar module was mounted at a distance of 0.2 m above the chest surface of the chicken, and this particular experiment was repeated for 20 times. The authors also used a reference ECG module (Biopac System) for extracting the breathing rate and heart rate of the broiler chicken and compared the accuracy of their proposed system. Experimental results demonstrated that the radar measurement closely matches the Biopac ECG acquisition module measurement and showed an accuracy of 96% for a short‐scale study.","PeriodicalId":22858,"journal":{"name":"The Journal of Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135515297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mohammad Sajad Fatolahi, Saman Hosseini-Hemati, A. Rastgou, Saeed Kharrati
The most common disadvantages of loss of excitation (LOE) impedance relay are its improper operation in the conditions of power system disturbances (PSD) and its long operation time. In this regard, to solve the mentioned problems and as a result improve the accuracy and speed of detecting the LOE events, four key variables including active power (Psg), reactive power (Qsg), load angle (δsg), and terminal voltage (Vsg) are selected, on the basis of an in‐depth theoretical‐ and simulation studies. These variables have been implemented in a precise combinational logic. In the developed LOE detection logic of this paper, the dependent parameters of Vsg and Qsg as well as Psg and δsg parameters are examined simultaneously in an AND logic cluster. If both the defined combinations detect the occurrence of LOE, the generator trip command is issued. Otherwise, the normal operation of the under‐study machine will continue. The results of the performed simulations in MATLAB/Simulink environment (2017b) during the detailed scenarios of LOE and PSD events on the IEEE 39‐bus standard system confirm the efficiency of the outlined LOE protection model. Meanwhile, its superiority from the viewpoints of accuracy, swiftness, and simplicity and cost of implementation are comprehensively compared with the other schemes.
{"title":"A multi‐variables loss of excitation protection scheme to improve the factors of accuracy and speed of detection than the conventional impedance relay","authors":"Mohammad Sajad Fatolahi, Saman Hosseini-Hemati, A. Rastgou, Saeed Kharrati","doi":"10.1049/tje2.12329","DOIUrl":"https://doi.org/10.1049/tje2.12329","url":null,"abstract":"The most common disadvantages of loss of excitation (LOE) impedance relay are its improper operation in the conditions of power system disturbances (PSD) and its long operation time. In this regard, to solve the mentioned problems and as a result improve the accuracy and speed of detecting the LOE events, four key variables including active power (Psg), reactive power (Qsg), load angle (δsg), and terminal voltage (Vsg) are selected, on the basis of an in‐depth theoretical‐ and simulation studies. These variables have been implemented in a precise combinational logic. In the developed LOE detection logic of this paper, the dependent parameters of Vsg and Qsg as well as Psg and δsg parameters are examined simultaneously in an AND logic cluster. If both the defined combinations detect the occurrence of LOE, the generator trip command is issued. Otherwise, the normal operation of the under‐study machine will continue. The results of the performed simulations in MATLAB/Simulink environment (2017b) during the detailed scenarios of LOE and PSD events on the IEEE 39‐bus standard system confirm the efficiency of the outlined LOE protection model. Meanwhile, its superiority from the viewpoints of accuracy, swiftness, and simplicity and cost of implementation are comprehensively compared with the other schemes.","PeriodicalId":22858,"journal":{"name":"The Journal of Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139296398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract In this work, the finite‐difference time‐domain (FDTD) method is employed to study electromagnetic problems with moving bodies in a moving system. The proposed approach consists in modeling objects with time‐varying positions and using the direct discretization of Maxwell's equations in space and time domains. Doppler effects are investigated for problems with moving observer, source, or reflector, in a moving frame. A distinction is also made between a high‐impedance or low‐impedance plane wave source in motion. The full‐wave electromagnetic simulations are compared with closed‐form equations that agree with wave theory. The proposed analysis shows that, for Doppler radars used every day, the motion of the Earth relative to the Cosmic Microwave Background has a negligible effect and only relative motions in the Earth frame are relevant.
{"title":"Electromagnetic analysis of moving structures in a moving reference frame","authors":"M. Marvasti, H. Boutayeb","doi":"10.1049/tje2.12302","DOIUrl":"https://doi.org/10.1049/tje2.12302","url":null,"abstract":"Abstract In this work, the finite‐difference time‐domain (FDTD) method is employed to study electromagnetic problems with moving bodies in a moving system. The proposed approach consists in modeling objects with time‐varying positions and using the direct discretization of Maxwell's equations in space and time domains. Doppler effects are investigated for problems with moving observer, source, or reflector, in a moving frame. A distinction is also made between a high‐impedance or low‐impedance plane wave source in motion. The full‐wave electromagnetic simulations are compared with closed‐form equations that agree with wave theory. The proposed analysis shows that, for Doppler radars used every day, the motion of the Earth relative to the Cosmic Microwave Background has a negligible effect and only relative motions in the Earth frame are relevant.","PeriodicalId":22858,"journal":{"name":"The Journal of Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135566332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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