Pub Date : 2022-11-11DOI: 10.1109/APET56294.2022.10073439
Jun Wang, Yun-hua Zhang, Jing Wang, Wei Jiang
The impedance based stability assessment method has been widely used to assess the stability of interconnected systems in different application areas. The output impedance (admittance) of the source subsystem and input impedance of the load subsystem should be obtained before the stability criterion of cascaded system is applied. This paper deals with the analysis of the source impedance for the droop-controlled permanent-magnet synchronous generator (PMSG) system. Transmission cables are also taken into account since it cannot be neglected in the low voltage microgrid i.e., DC microgrid (DC MG). This paper develops the mathematical model of the PMSG system, derives the output impedance of the source subsystem and shows the effect of parameters variation such as droop coefficient, feeder impedance and control bandwidth on source impedance. The aforementioned analytical result is confirmed by time domain simulations.
{"title":"Source Impedance Analysis of a DC Microgrid under Droop Control","authors":"Jun Wang, Yun-hua Zhang, Jing Wang, Wei Jiang","doi":"10.1109/APET56294.2022.10073439","DOIUrl":"https://doi.org/10.1109/APET56294.2022.10073439","url":null,"abstract":"The impedance based stability assessment method has been widely used to assess the stability of interconnected systems in different application areas. The output impedance (admittance) of the source subsystem and input impedance of the load subsystem should be obtained before the stability criterion of cascaded system is applied. This paper deals with the analysis of the source impedance for the droop-controlled permanent-magnet synchronous generator (PMSG) system. Transmission cables are also taken into account since it cannot be neglected in the low voltage microgrid i.e., DC microgrid (DC MG). This paper develops the mathematical model of the PMSG system, derives the output impedance of the source subsystem and shows the effect of parameters variation such as droop coefficient, feeder impedance and control bandwidth on source impedance. The aforementioned analytical result is confirmed by time domain simulations.","PeriodicalId":201727,"journal":{"name":"2022 Asia Power and Electrical Technology Conference (APET)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121828068","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}
Pub Date : 2022-11-11DOI: 10.1109/APET56294.2022.10072833
Yuchen Liu, Xiaoqin Lyu, Mingyuan Chang
The low-frequency oscillation (LFO) problem has occurred in electrified railway train-network system, which will threaten the safe and stable operation of the trains. In this paper, based on the phase-domain impedance model of China high speed trains, and considering the actual network topology of multi-train-network system with three-phase power grid, traction transformer, traction network, and the trains, the modal analysis is adopted to study the system oscillation modes and propagation characteristics. The participation factor, observability and controllability of each network node to the critical LFO mode under the bilateral and unilateral power supply modes are analyzed and compared. Finally, the correctness of the theoretical analysis is verified by the electromagnetic transient simulations.
{"title":"Research on Low-frequency Oscillation of Multi-train-network System Based on Modal Analysis","authors":"Yuchen Liu, Xiaoqin Lyu, Mingyuan Chang","doi":"10.1109/APET56294.2022.10072833","DOIUrl":"https://doi.org/10.1109/APET56294.2022.10072833","url":null,"abstract":"The low-frequency oscillation (LFO) problem has occurred in electrified railway train-network system, which will threaten the safe and stable operation of the trains. In this paper, based on the phase-domain impedance model of China high speed trains, and considering the actual network topology of multi-train-network system with three-phase power grid, traction transformer, traction network, and the trains, the modal analysis is adopted to study the system oscillation modes and propagation characteristics. The participation factor, observability and controllability of each network node to the critical LFO mode under the bilateral and unilateral power supply modes are analyzed and compared. Finally, the correctness of the theoretical analysis is verified by the electromagnetic transient simulations.","PeriodicalId":201727,"journal":{"name":"2022 Asia Power and Electrical Technology Conference (APET)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125364074","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}
Pub Date : 2022-11-11DOI: 10.1109/APET56294.2022.10072884
Du Hexi, Wu Jinmeng, Meng Fangang
Synchronous rectification is an effective method to improve efficiency and reduce loss of LLC resonant converter. In this paper, without introducing any auxiliary detection devices, a mathematical model is established to theoretically calculate the turn-on and turn-off times of the primary side and secondary side MOS in different working regions, and according to the delay and dead zone transient requirements in the hardware circuit The digital algorithm is used in the DSP processor for real-time control of synchronous rectification, which significantly reduces the design complexity of synchronous rectification control and improves the flexibility of control. And the effectiveness of the synchronous rectification control strategy is verified by 12V/125A1.5kW LLC simulation and experiment.
{"title":"Research on Synchronous Rectifier Digital Control Method of LLC Converter","authors":"Du Hexi, Wu Jinmeng, Meng Fangang","doi":"10.1109/APET56294.2022.10072884","DOIUrl":"https://doi.org/10.1109/APET56294.2022.10072884","url":null,"abstract":"Synchronous rectification is an effective method to improve efficiency and reduce loss of LLC resonant converter. In this paper, without introducing any auxiliary detection devices, a mathematical model is established to theoretically calculate the turn-on and turn-off times of the primary side and secondary side MOS in different working regions, and according to the delay and dead zone transient requirements in the hardware circuit The digital algorithm is used in the DSP processor for real-time control of synchronous rectification, which significantly reduces the design complexity of synchronous rectification control and improves the flexibility of control. And the effectiveness of the synchronous rectification control strategy is verified by 12V/125A1.5kW LLC simulation and experiment.","PeriodicalId":201727,"journal":{"name":"2022 Asia Power and Electrical Technology Conference (APET)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116607323","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}
Carrying out post project evaluation on electricity projects actively could provide the experience for future projects which can increase the investment effect. This paper is based on the construction characteristics of the region in the eastern part of Inner Mongolia. From the whole process of the construction of transmission, the evaluation index system is determined. A certain transformation engineering project was analyzed, which could provide guidance and reference for the evaluation of the follow-up projects in eastern Inner Mongolia.
{"title":"Benefit Analysis of a Power Transmission Project in the East of Inner Mongolia","authors":"Jiao Wang, Qingzhuang Lin, Lijun Zhao, Jingshu Xing, S. Yang, Xia Miao","doi":"10.1109/APET56294.2022.10072498","DOIUrl":"https://doi.org/10.1109/APET56294.2022.10072498","url":null,"abstract":"Carrying out post project evaluation on electricity projects actively could provide the experience for future projects which can increase the investment effect. This paper is based on the construction characteristics of the region in the eastern part of Inner Mongolia. From the whole process of the construction of transmission, the evaluation index system is determined. A certain transformation engineering project was analyzed, which could provide guidance and reference for the evaluation of the follow-up projects in eastern Inner Mongolia.","PeriodicalId":201727,"journal":{"name":"2022 Asia Power and Electrical Technology Conference (APET)","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121752365","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}
Pub Date : 2022-11-11DOI: 10.1109/APET56294.2022.10073074
Zhenyao Li, Xueyi Wang, D. Gan
With the high penetration of renewable energy into the power system and the development and application of power electronic devices, the operation scale of the power system is increasing. Meanwhile, the frequency dynamic behavior of the power system is becoming more complex, which urgently needs effective frequency stability analysis methods and control means. To overcome the computational errors in the traditional system frequency response model, we established a frequency response model based on the full-state model of the power system. First, through the analytical solution of the time domain response of the state variables, we obtain the quantitative relationship between the system frequency-related characteristic quantities and the system parameters. Then, we transform the frequency stability problem into the quadratic eigenvalue problem and demonstrate that the reduction of system inertia increases the imaginary part of eigenvalues, which reduces the disturbance rejection capability of the system frequency inertia response. Finally, the correctness and validity of the above conclusions and methods are verified in the 10-machine 39-node system.
{"title":"Inertia Response of Power System Frequency Dynamics Based on The Quadratic Eigenvalue Approach","authors":"Zhenyao Li, Xueyi Wang, D. Gan","doi":"10.1109/APET56294.2022.10073074","DOIUrl":"https://doi.org/10.1109/APET56294.2022.10073074","url":null,"abstract":"With the high penetration of renewable energy into the power system and the development and application of power electronic devices, the operation scale of the power system is increasing. Meanwhile, the frequency dynamic behavior of the power system is becoming more complex, which urgently needs effective frequency stability analysis methods and control means. To overcome the computational errors in the traditional system frequency response model, we established a frequency response model based on the full-state model of the power system. First, through the analytical solution of the time domain response of the state variables, we obtain the quantitative relationship between the system frequency-related characteristic quantities and the system parameters. Then, we transform the frequency stability problem into the quadratic eigenvalue problem and demonstrate that the reduction of system inertia increases the imaginary part of eigenvalues, which reduces the disturbance rejection capability of the system frequency inertia response. Finally, the correctness and validity of the above conclusions and methods are verified in the 10-machine 39-node system.","PeriodicalId":201727,"journal":{"name":"2022 Asia Power and Electrical Technology Conference (APET)","volume":"149 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131955004","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}
As the scale and complexity of the grid continues to escalate, the short-circuit current level of the power system keep increasing. Fast circuit breaker can effectively reduce the impact of short-circuit current and become one of the research hotspots of high-voltage circuit breaker (HVCB). The novel repulsive hydraulic operating mechanism proposed in this paper takes the comprehensive advantages of the fast response characteristic of repulsion mechanism and the characteristic of large output in the large stroke range of the hydraulic mechanism, which can help to achieve rapid opening of HVCB. The working principle and technical route of the proposed repulsive hydraulic operating mechanism are expounded. And the research on repulsion device and hydraulic system is conducted respectively from functional requirement, system modeling and parameter optimization. On the basis of which, the prototype of 252kV circuit breaker driven by the novel repulsion hydraulic mechanism is built to verify the correctness of the design and optimization method for the novel operating mechanism, and the feasibility of the novel repulsion hydraulic mechanism used to drive HVCB to achieve rapid opening. The tests show that the 252kV fast circuit breaker can complete arc extinguishing within 25ms, which is about forty percent less than conventional circuit breakers.
{"title":"A Novel Repulsion Hydraulic Operating Mechanism for Fast High Voltage Circuit Breaker","authors":"Fei Yan, Baoying He, Xiaohui Duan, Dawei He, Yu Liu, Jiayuan Xu","doi":"10.1109/APET56294.2022.10072928","DOIUrl":"https://doi.org/10.1109/APET56294.2022.10072928","url":null,"abstract":"As the scale and complexity of the grid continues to escalate, the short-circuit current level of the power system keep increasing. Fast circuit breaker can effectively reduce the impact of short-circuit current and become one of the research hotspots of high-voltage circuit breaker (HVCB). The novel repulsive hydraulic operating mechanism proposed in this paper takes the comprehensive advantages of the fast response characteristic of repulsion mechanism and the characteristic of large output in the large stroke range of the hydraulic mechanism, which can help to achieve rapid opening of HVCB. The working principle and technical route of the proposed repulsive hydraulic operating mechanism are expounded. And the research on repulsion device and hydraulic system is conducted respectively from functional requirement, system modeling and parameter optimization. On the basis of which, the prototype of 252kV circuit breaker driven by the novel repulsion hydraulic mechanism is built to verify the correctness of the design and optimization method for the novel operating mechanism, and the feasibility of the novel repulsion hydraulic mechanism used to drive HVCB to achieve rapid opening. The tests show that the 252kV fast circuit breaker can complete arc extinguishing within 25ms, which is about forty percent less than conventional circuit breakers.","PeriodicalId":201727,"journal":{"name":"2022 Asia Power and Electrical Technology Conference (APET)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131529600","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}
Pub Date : 2022-11-11DOI: 10.1109/APET56294.2022.10073220
Liu Kai, Fan Yongxue, Ding Lei, Wang Peng
To improve the competitiveness of power grid, the rapid transformation from traditional mode to digital mode is of great importance. Therefore, the middleground architecture is proposed to promote the digital transformation of power grid in this paper. Many digital technologies, such as cloud computing, big data, internet of things, A.I. and 5G, are used to realize the rapid and efficient digital transformation, and promote the integration of digital technology and power grid. Meanwhile, information digitization, and business digitization and digital business are presented to break the situation of vertical strength, horizontal weakness and information island, which can create a win-win, shared and opened business platform. At last, this paper formulates some standards to help realize unified governance, analysis and value mining, which can promote the transformation of power grid enterprises to digitization.
{"title":"Research on the Digital Transformation of Power Grid Based on Middleground Architecture","authors":"Liu Kai, Fan Yongxue, Ding Lei, Wang Peng","doi":"10.1109/APET56294.2022.10073220","DOIUrl":"https://doi.org/10.1109/APET56294.2022.10073220","url":null,"abstract":"To improve the competitiveness of power grid, the rapid transformation from traditional mode to digital mode is of great importance. Therefore, the middleground architecture is proposed to promote the digital transformation of power grid in this paper. Many digital technologies, such as cloud computing, big data, internet of things, A.I. and 5G, are used to realize the rapid and efficient digital transformation, and promote the integration of digital technology and power grid. Meanwhile, information digitization, and business digitization and digital business are presented to break the situation of vertical strength, horizontal weakness and information island, which can create a win-win, shared and opened business platform. At last, this paper formulates some standards to help realize unified governance, analysis and value mining, which can promote the transformation of power grid enterprises to digitization.","PeriodicalId":201727,"journal":{"name":"2022 Asia Power and Electrical Technology Conference (APET)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115375012","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}
Pub Date : 2022-11-11DOI: 10.1109/APET56294.2022.10072800
L. Qin, Ding Zejun, Mo Xizhe, Wang Song, Zhao Linjie, Li Hao, Yang Yuxuan, Zou Lin, Liu Xu
In order to realize the real-time control of the charging and discharging process of lead-acid batteries in substations, this paper takes 2V, 200Ah valve-regulated lead-acid batteries as the research object. Based on experimental data and existing data information, the establishment considers electricity, heat, nonlinear behavior and temperature estimation, The nonlinear dynamic equivalent circuit model of VRLA battery. Study the influence of different discharge rates on the battery capacity; study the function of the non-linear parameters of the battery and the battery current and open circuit voltage, and study the influence of the battery temperature on the internal parameters. The experimental results show that the model results match the experimental results completely.
{"title":"Research on Extraction of Discharge Behavior Parameters of Valve-regulated Lead-acid Battery Based on Dynamic Equivalent Circuit Model","authors":"L. Qin, Ding Zejun, Mo Xizhe, Wang Song, Zhao Linjie, Li Hao, Yang Yuxuan, Zou Lin, Liu Xu","doi":"10.1109/APET56294.2022.10072800","DOIUrl":"https://doi.org/10.1109/APET56294.2022.10072800","url":null,"abstract":"In order to realize the real-time control of the charging and discharging process of lead-acid batteries in substations, this paper takes 2V, 200Ah valve-regulated lead-acid batteries as the research object. Based on experimental data and existing data information, the establishment considers electricity, heat, nonlinear behavior and temperature estimation, The nonlinear dynamic equivalent circuit model of VRLA battery. Study the influence of different discharge rates on the battery capacity; study the function of the non-linear parameters of the battery and the battery current and open circuit voltage, and study the influence of the battery temperature on the internal parameters. The experimental results show that the model results match the experimental results completely.","PeriodicalId":201727,"journal":{"name":"2022 Asia Power and Electrical Technology Conference (APET)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124268065","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}
Pub Date : 2022-11-11DOI: 10.1109/APET56294.2022.10073450
D. Acevedo, Andres Apolinario, Steve Camargo
The objective of the work was to evaluate the performance of the 265W solar photovoltaic system that was installed in a house in La Ribera, Huancayo. The type of research used is technological, experimental level, and the research design was factorial design 32. The results were obtained through the use of the multimeter. The analysis of residuals could prove that all the experimental data collected were consistent, since the variation of residuals is between +2 and −2, and the p-values of the variance analysis are less than the reliability coefficient. The main conclusion of the factorial design 32, is that it guides us to perform the experimental work with nine scenarios or combinations, of which the first scenario where it is located at 22° and positioned to the north and generates 40.7 volts, which is the highest performance of all combinations.
{"title":"Performance Analysis of a Photovoltaic System Using Factorial Design in the Sector La Ribera, Huancayo, June 2022","authors":"D. Acevedo, Andres Apolinario, Steve Camargo","doi":"10.1109/APET56294.2022.10073450","DOIUrl":"https://doi.org/10.1109/APET56294.2022.10073450","url":null,"abstract":"The objective of the work was to evaluate the performance of the 265W solar photovoltaic system that was installed in a house in La Ribera, Huancayo. The type of research used is technological, experimental level, and the research design was factorial design 32. The results were obtained through the use of the multimeter. The analysis of residuals could prove that all the experimental data collected were consistent, since the variation of residuals is between +2 and −2, and the p-values of the variance analysis are less than the reliability coefficient. The main conclusion of the factorial design 32, is that it guides us to perform the experimental work with nine scenarios or combinations, of which the first scenario where it is located at 22° and positioned to the north and generates 40.7 volts, which is the highest performance of all combinations.","PeriodicalId":201727,"journal":{"name":"2022 Asia Power and Electrical Technology Conference (APET)","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124539690","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}
Pub Date : 2022-11-11DOI: 10.1109/APET56294.2022.10072624
Zhi-xia Zhang, Yingyue Pan, Mingming Jiang
Low-voltage distribution network leakage accident will directly affect the personal and property safety of users if not be handled in time, and a large area of power failure will also bring great losses to the national economy. To reduce the low voltage distribution network leakage accident, the main principle, method and technology for low voltage distribution network leakage accident protection have been studied, and the zero sequence current protection and residual current protection principle have also been analyzed. The method characteristics and scope of application of the amplitude comparison, current pulse, comparison of amplitude and phase angle, and phasor mutation have been studied, which provides a basis for the research and development of leakage protection equipment of low-voltage distribution network.
{"title":"Research on Key Technologies and Precise Protection of Leakage Accidents in Modern Distribution Network","authors":"Zhi-xia Zhang, Yingyue Pan, Mingming Jiang","doi":"10.1109/APET56294.2022.10072624","DOIUrl":"https://doi.org/10.1109/APET56294.2022.10072624","url":null,"abstract":"Low-voltage distribution network leakage accident will directly affect the personal and property safety of users if not be handled in time, and a large area of power failure will also bring great losses to the national economy. To reduce the low voltage distribution network leakage accident, the main principle, method and technology for low voltage distribution network leakage accident protection have been studied, and the zero sequence current protection and residual current protection principle have also been analyzed. The method characteristics and scope of application of the amplitude comparison, current pulse, comparison of amplitude and phase angle, and phasor mutation have been studied, which provides a basis for the research and development of leakage protection equipment of low-voltage distribution network.","PeriodicalId":201727,"journal":{"name":"2022 Asia Power and Electrical Technology Conference (APET)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114771938","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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