Pub Date : 2019-03-01DOI: 10.1109/ICGEA.2019.8880765
Bo Xu, Shenzhi Xu, Yumin Zhang
To obtain optimal inspection rates of power equipment, this paper presents an inspection rates optimization model for power equipment asset management which explicitly considers equipment aging using Markov process. The model combines random and deterioration failure modes with maintenance activities. Opportunistic maintenance strategy in long-run time span with non-periodic inspections is proposed to fully benefit from the economic dependence between different failure modes while the existing Markov maintenance models can't incorporate opportunistic maintenance strategy. In the model, when random failure occurs, the opportunity to maintain deterioration failure is considered. The model can optimize the non-periodic inspection rates for power equipment by minimizing the total cost consisting of maintenance cost, repair cost and expected energy not supplied (EENS) cost. Typical substation configuration is used to demonstrate the feasibility of the proposed model. The analysis results in the case study show that opportunistic maintenance strategy has significant impacts on equipment reliability and optimal inspection rates.
{"title":"Determining Optimal Inspection Rates of Power Equipment Considering Opportunistic Maintenance Strategy","authors":"Bo Xu, Shenzhi Xu, Yumin Zhang","doi":"10.1109/ICGEA.2019.8880765","DOIUrl":"https://doi.org/10.1109/ICGEA.2019.8880765","url":null,"abstract":"To obtain optimal inspection rates of power equipment, this paper presents an inspection rates optimization model for power equipment asset management which explicitly considers equipment aging using Markov process. The model combines random and deterioration failure modes with maintenance activities. Opportunistic maintenance strategy in long-run time span with non-periodic inspections is proposed to fully benefit from the economic dependence between different failure modes while the existing Markov maintenance models can't incorporate opportunistic maintenance strategy. In the model, when random failure occurs, the opportunity to maintain deterioration failure is considered. The model can optimize the non-periodic inspection rates for power equipment by minimizing the total cost consisting of maintenance cost, repair cost and expected energy not supplied (EENS) cost. Typical substation configuration is used to demonstrate the feasibility of the proposed model. The analysis results in the case study show that opportunistic maintenance strategy has significant impacts on equipment reliability and optimal inspection rates.","PeriodicalId":170713,"journal":{"name":"2019 IEEE 3rd International Conference on Green Energy and Applications (ICGEA)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116458810","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 : 2019-03-01DOI: 10.1109/ICGEA.2019.8880741
Hongtao Yang, A. Tang, Qiushi Xu, Xu Zheng
Aiming at the phenomenon of low frequency oscillation caused by ultra high voltage direct current operation, this paper intends to adopt the method of parameter optimization of power system stabilizer to improve the small interference stability of the system. In order to ensure the rapidity and accuracy of small interference calculation, this paper first establishes a small interference linearization model for high voltage direct current system based on voltage source converter, and then proposes a coordinated optimization method for supplementary damping controller and power system stabilizer of DC voltage source converter under multiple operation modes. The method can improve the small interference stability of AC power grid with ultra high voltage direct curren in an all-round way. Finally, the method is validated by simulation software. The simulation results show that the proposed method can effectively improve the small interference stability of the system.
{"title":"Low Frequency Oscillation Suppression Strategy for AC Power Grid with UHVDC","authors":"Hongtao Yang, A. Tang, Qiushi Xu, Xu Zheng","doi":"10.1109/ICGEA.2019.8880741","DOIUrl":"https://doi.org/10.1109/ICGEA.2019.8880741","url":null,"abstract":"Aiming at the phenomenon of low frequency oscillation caused by ultra high voltage direct current operation, this paper intends to adopt the method of parameter optimization of power system stabilizer to improve the small interference stability of the system. In order to ensure the rapidity and accuracy of small interference calculation, this paper first establishes a small interference linearization model for high voltage direct current system based on voltage source converter, and then proposes a coordinated optimization method for supplementary damping controller and power system stabilizer of DC voltage source converter under multiple operation modes. The method can improve the small interference stability of AC power grid with ultra high voltage direct curren in an all-round way. Finally, the method is validated by simulation software. The simulation results show that the proposed method can effectively improve the small interference stability of the system.","PeriodicalId":170713,"journal":{"name":"2019 IEEE 3rd International Conference on Green Energy and Applications (ICGEA)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126108701","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 : 2019-03-01DOI: 10.1109/ICGEA.2019.8880758
Rundong Lv, Ke Zhu
The DC bias caused by single pole-ground mode or bipolar unbalanced mode of HVDC transmission or geomagnetic induced current phenomenon may lead to the measuring CT saturation, which may affect the measurement performance. Therefore, it is necessary to evaluate the saturation degree of the CT. By using the effective permeability, analyzing the equivalent model of CT under DC bias state and combining with the electromagnetic relationship between flux and voltage, the expression of the saturation degree, DC current and circuit parameters is analyzed and derived. By simulating different types of CT, the effectiveness of the analytical expression is verified, and the influence on the saturation degree is analyzed. The actual power system parameters are used for numerical analysis, and the rough estimation of the measurement error is used to show the specific application of the method for analyzing the DC bias magnetic conditions of the measuring CT.
{"title":"Quantitative Analysis of Saturation of Measurement Current Transformer by Direct Current Bias","authors":"Rundong Lv, Ke Zhu","doi":"10.1109/ICGEA.2019.8880758","DOIUrl":"https://doi.org/10.1109/ICGEA.2019.8880758","url":null,"abstract":"The DC bias caused by single pole-ground mode or bipolar unbalanced mode of HVDC transmission or geomagnetic induced current phenomenon may lead to the measuring CT saturation, which may affect the measurement performance. Therefore, it is necessary to evaluate the saturation degree of the CT. By using the effective permeability, analyzing the equivalent model of CT under DC bias state and combining with the electromagnetic relationship between flux and voltage, the expression of the saturation degree, DC current and circuit parameters is analyzed and derived. By simulating different types of CT, the effectiveness of the analytical expression is verified, and the influence on the saturation degree is analyzed. The actual power system parameters are used for numerical analysis, and the rough estimation of the measurement error is used to show the specific application of the method for analyzing the DC bias magnetic conditions of the measuring CT.","PeriodicalId":170713,"journal":{"name":"2019 IEEE 3rd International Conference on Green Energy and Applications (ICGEA)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114229335","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 : 2019-03-01DOI: 10.1109/icgea.2019.8880759
{"title":"2019 3rd IEEE International Conference on Green Energy and Applications","authors":"","doi":"10.1109/icgea.2019.8880759","DOIUrl":"https://doi.org/10.1109/icgea.2019.8880759","url":null,"abstract":"","PeriodicalId":170713,"journal":{"name":"2019 IEEE 3rd International Conference on Green Energy and Applications (ICGEA)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123426115","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 : 2019-03-01DOI: 10.1109/ICGEA.2019.8880763
Hu Hong, W. Hua
A multi-source coordinated model considering nuclear power participation in peak load regulation is proposed. On the premise of meeting the safety constrains of nuclear power plant when participating in optimal operation, It's capability of peak load regulation is effectively improved. The multi-source coordinated model realizes the maximum absorption of wind power output and the improvement of system economy. The model taking the minimum total cost of power system as the objective function, using two-stage scheduling to determine whether nuclear power units participate in peak load regulation, and taking account of the deep peak load regulation of the thermal power units at the same time. Simulation results verify the validity of the model. With multi-source coordinated model, nuclear power units can choose the most economical load following scheme according to the actual situation on the premise of meeting safety constraints. The total cost of power system after optimization is less than the model when nuclear power plants running with basic load. And more wind power output can be absorbed at the same time.
{"title":"A Multi-source Coordinated Model Considering Nuclear Power Participation in Peak Load Regulation","authors":"Hu Hong, W. Hua","doi":"10.1109/ICGEA.2019.8880763","DOIUrl":"https://doi.org/10.1109/ICGEA.2019.8880763","url":null,"abstract":"A multi-source coordinated model considering nuclear power participation in peak load regulation is proposed. On the premise of meeting the safety constrains of nuclear power plant when participating in optimal operation, It's capability of peak load regulation is effectively improved. The multi-source coordinated model realizes the maximum absorption of wind power output and the improvement of system economy. The model taking the minimum total cost of power system as the objective function, using two-stage scheduling to determine whether nuclear power units participate in peak load regulation, and taking account of the deep peak load regulation of the thermal power units at the same time. Simulation results verify the validity of the model. With multi-source coordinated model, nuclear power units can choose the most economical load following scheme according to the actual situation on the premise of meeting safety constraints. The total cost of power system after optimization is less than the model when nuclear power plants running with basic load. And more wind power output can be absorbed at the same time.","PeriodicalId":170713,"journal":{"name":"2019 IEEE 3rd International Conference on Green Energy and Applications (ICGEA)","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121891032","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 : 2019-03-01DOI: 10.1109/ICGEA.2019.8880778
Yongchao Sun, Mei Sun, Xuelian Tang
Energy crisis, global warming and environmental pollution has become global public problem. Now around the world, renewables are established as mainstream sources of energy. As main part of primary energy, crude oil shall certainly be affected deeply by renewable energy sources in the future. The status of renewables and crude oil are introduced at first. And the influence of renewables on crude oil future market are analyzed in demand, geopolitics and domestic political situation, speculation and psychological anticipation, and market operation anticipation. The conclusions are concluded at last.
{"title":"Influence Analysis of Renewable Energy on Crude Oil Future Market","authors":"Yongchao Sun, Mei Sun, Xuelian Tang","doi":"10.1109/ICGEA.2019.8880778","DOIUrl":"https://doi.org/10.1109/ICGEA.2019.8880778","url":null,"abstract":"Energy crisis, global warming and environmental pollution has become global public problem. Now around the world, renewables are established as mainstream sources of energy. As main part of primary energy, crude oil shall certainly be affected deeply by renewable energy sources in the future. The status of renewables and crude oil are introduced at first. And the influence of renewables on crude oil future market are analyzed in demand, geopolitics and domestic political situation, speculation and psychological anticipation, and market operation anticipation. The conclusions are concluded at last.","PeriodicalId":170713,"journal":{"name":"2019 IEEE 3rd International Conference on Green Energy and Applications (ICGEA)","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124261679","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 : 2019-03-01DOI: 10.1109/ICGEA.2019.8880784
Chaolei Chen, Yuanxiong Cheng, F. Meng
The conventional electric wheels suffer from serious technical problem, called as vertical vibration negative effect caused by large unsprung mass brought by in-wheel motor. The paper presents a novel configuration of multi-functional integrated electric wheel with in-wheel suspension. New configuration avoids the increase of unsprung mass. Based on quarter-vehicle model, wheel vertical dynamics performance is investigated for the proposed suspension system by numerical modeling and simulation method. The vehicle dynamic performance index is evaluated by the mean square value, while model input is taken from the random excitation of the road surface. According to the size of the suspension within the wheel, the optimal stiffness and damping coefficient are calculated by using the linear weighted sum method to achieve the most excellent vehicle dynamic performance.
{"title":"Optimum Design of a Novel In-Wheel Suspension of the Electric Wheel","authors":"Chaolei Chen, Yuanxiong Cheng, F. Meng","doi":"10.1109/ICGEA.2019.8880784","DOIUrl":"https://doi.org/10.1109/ICGEA.2019.8880784","url":null,"abstract":"The conventional electric wheels suffer from serious technical problem, called as vertical vibration negative effect caused by large unsprung mass brought by in-wheel motor. The paper presents a novel configuration of multi-functional integrated electric wheel with in-wheel suspension. New configuration avoids the increase of unsprung mass. Based on quarter-vehicle model, wheel vertical dynamics performance is investigated for the proposed suspension system by numerical modeling and simulation method. The vehicle dynamic performance index is evaluated by the mean square value, while model input is taken from the random excitation of the road surface. According to the size of the suspension within the wheel, the optimal stiffness and damping coefficient are calculated by using the linear weighted sum method to achieve the most excellent vehicle dynamic performance.","PeriodicalId":170713,"journal":{"name":"2019 IEEE 3rd International Conference on Green Energy and Applications (ICGEA)","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126389766","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 energy storage system participates in the power grid Frequency Regulation (FR), which can give full play to the advantages of fast energy storage return speed and high adjustment precision. Based on the optimal response FR scheduling instruction of energy storage power station, based on K-means clustering method, the comprehensive performance index of FR (adjustment speed, response time and adjustment precision) is analyzed. The different energy flow states of power grid and energy storage unit are summarized. The impact of performance indicators, explored the battery cell control strategy to achieve a network-storage win-win energy storage. By modifying the existing response sequence and combining the SOC state of each unit, the dynamic adaptive sensing adapts to the grid automatic power generation control (AGC) variable load task, so that the fire storage combined FR system can obtain more compensation and reduce storage. The total number of foldbacks can be reduced to reduce operating costs.
{"title":"Energy Storage Frequency Regulation Energy Management Strategy Based on K-Means Analysis","authors":"Chen Hao, Jia Yanbing, Zheng Jin, Zhu Yanfang, Luo Gang, Xie Dong","doi":"10.1109/ICGEA.2019.8880782","DOIUrl":"https://doi.org/10.1109/ICGEA.2019.8880782","url":null,"abstract":"The energy storage system participates in the power grid Frequency Regulation (FR), which can give full play to the advantages of fast energy storage return speed and high adjustment precision. Based on the optimal response FR scheduling instruction of energy storage power station, based on K-means clustering method, the comprehensive performance index of FR (adjustment speed, response time and adjustment precision) is analyzed. The different energy flow states of power grid and energy storage unit are summarized. The impact of performance indicators, explored the battery cell control strategy to achieve a network-storage win-win energy storage. By modifying the existing response sequence and combining the SOC state of each unit, the dynamic adaptive sensing adapts to the grid automatic power generation control (AGC) variable load task, so that the fire storage combined FR system can obtain more compensation and reduce storage. The total number of foldbacks can be reduced to reduce operating costs.","PeriodicalId":170713,"journal":{"name":"2019 IEEE 3rd International Conference on Green Energy and Applications (ICGEA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131311385","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 : 2019-03-01DOI: 10.1109/ICGEA.2019.8880781
Libin Yang, Shufeng Guo, Chunmeng Chen, Fan Wang, Guoyi Xu, T. Bi
Frequency control of the power system with high penetration level of converter connected renewable power generation has become a challenge to system operators. In order for reliable operation of power system, variable speed wind turbines(WT) are required to provide frequency control to power system. This paper focuses on the frequency controller parameter value selection of the variable speed WTs. The WTs are controlled to have both the inertial response and primary frequency control capability which is similar to the synchronous generators. The de-load level of the WT is discussed, according to the operation curves, the value for the frequency controller gains is discussed. Matlab/Simulink is adopted to demonstrate the frequency control performances with different controller parameter values, the results show the variable speed WTs can be controlled to have similar frequency response as the synchronous generators, through proper controller value selection the WTs can have a better frequency control performance, which is helpful for the safe operation of the power system.
{"title":"Parameter Value Selection of Wind Turbines Frequency Controller","authors":"Libin Yang, Shufeng Guo, Chunmeng Chen, Fan Wang, Guoyi Xu, T. Bi","doi":"10.1109/ICGEA.2019.8880781","DOIUrl":"https://doi.org/10.1109/ICGEA.2019.8880781","url":null,"abstract":"Frequency control of the power system with high penetration level of converter connected renewable power generation has become a challenge to system operators. In order for reliable operation of power system, variable speed wind turbines(WT) are required to provide frequency control to power system. This paper focuses on the frequency controller parameter value selection of the variable speed WTs. The WTs are controlled to have both the inertial response and primary frequency control capability which is similar to the synchronous generators. The de-load level of the WT is discussed, according to the operation curves, the value for the frequency controller gains is discussed. Matlab/Simulink is adopted to demonstrate the frequency control performances with different controller parameter values, the results show the variable speed WTs can be controlled to have similar frequency response as the synchronous generators, through proper controller value selection the WTs can have a better frequency control performance, which is helpful for the safe operation of the power system.","PeriodicalId":170713,"journal":{"name":"2019 IEEE 3rd International Conference on Green Energy and Applications (ICGEA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128713375","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 : 2019-03-01DOI: 10.1109/ICGEA.2019.8880768
Xu Yu, W. Jianjun, Liu Weihao, Jiang Yijun, Xu Ting, Zhang Jinbo
There are many problems in traditional manual inspection, such as poor real-time performance, complex operation and large environmental impact on monitoring results when using ultrasonic and ultra high frequency (UHF) inspection methods. In order to realize online monitoring of partial discharge (PD) in high-voltage switchgears, a live display capacitance sensor equipped with high-voltage switchgear is proposed to acquire discharge pulse and monitor the discharge information of switchgear in real time. With the technology of FPGA, the sampling frequency of 50MHz is used to collect one million data points in 10 milliseconds and a half cycle. Hanning window function data processing technology and fast Fourier transform (FFT) technology are used to obtain the high frequency discharge spectrum of the internal ports and insulators of high-voltage switchgear cabinet, thus realizing the online monitoring of PD, and greatly reducing the cost of the monitoring circuit. It is convenient for popularization and application, and meets the online monitoring requirements of PD through practical tests.
{"title":"Online Monitoring Device for Partial Discharge in High-Voltage Switchgear Based on Capacitance Coupling Method","authors":"Xu Yu, W. Jianjun, Liu Weihao, Jiang Yijun, Xu Ting, Zhang Jinbo","doi":"10.1109/ICGEA.2019.8880768","DOIUrl":"https://doi.org/10.1109/ICGEA.2019.8880768","url":null,"abstract":"There are many problems in traditional manual inspection, such as poor real-time performance, complex operation and large environmental impact on monitoring results when using ultrasonic and ultra high frequency (UHF) inspection methods. In order to realize online monitoring of partial discharge (PD) in high-voltage switchgears, a live display capacitance sensor equipped with high-voltage switchgear is proposed to acquire discharge pulse and monitor the discharge information of switchgear in real time. With the technology of FPGA, the sampling frequency of 50MHz is used to collect one million data points in 10 milliseconds and a half cycle. Hanning window function data processing technology and fast Fourier transform (FFT) technology are used to obtain the high frequency discharge spectrum of the internal ports and insulators of high-voltage switchgear cabinet, thus realizing the online monitoring of PD, and greatly reducing the cost of the monitoring circuit. It is convenient for popularization and application, and meets the online monitoring requirements of PD through practical tests.","PeriodicalId":170713,"journal":{"name":"2019 IEEE 3rd International Conference on Green Energy and Applications (ICGEA)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134015301","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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