Pub Date : 2018-04-16DOI: 10.1109/TDC.2018.8440552
Longfei Wei, L. P. Rondon, A. Moghadasi, A. Sarwat
The Advanced Metering Infrastructure (AMI) is a vital element in the current development of the smart grid. AMI technologies provide electric utilities with an effective way of continuous monitoring and remote control of smart grid components. However, owing to its increasing scale and cyber-physical nature, the AMI has been faced with security threats in both cyber and physical domains. This paper provides a comprehensive review of the crucial cyber-physical attacks and counter defense mechanisms in the AMI. First, two attack surfaces are surveyed in the AMI including the communication network and smart meters. The potential cyber-physical attacks are then reviewed for each attack surface. Next, the attack models and their cyber and physical impacts on the smart grid are studied for comparison. Counter defense mechanisms that help mitigate these security threats are discussed. Finally, several mathematical tools which may help in analysis and implementation of security solutions are summarized.
{"title":"Review of Cyber-Physical Attacks and Counter Defense Mechanisms for Advanced Metering Infrastructure in Smart Grid","authors":"Longfei Wei, L. P. Rondon, A. Moghadasi, A. Sarwat","doi":"10.1109/TDC.2018.8440552","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440552","url":null,"abstract":"The Advanced Metering Infrastructure (AMI) is a vital element in the current development of the smart grid. AMI technologies provide electric utilities with an effective way of continuous monitoring and remote control of smart grid components. However, owing to its increasing scale and cyber-physical nature, the AMI has been faced with security threats in both cyber and physical domains. This paper provides a comprehensive review of the crucial cyber-physical attacks and counter defense mechanisms in the AMI. First, two attack surfaces are surveyed in the AMI including the communication network and smart meters. The potential cyber-physical attacks are then reviewed for each attack surface. Next, the attack models and their cyber and physical impacts on the smart grid are studied for comparison. Counter defense mechanisms that help mitigate these security threats are discussed. Finally, several mathematical tools which may help in analysis and implementation of security solutions are summarized.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"39 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90254785","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 : 2018-04-16DOI: 10.1109/TDC.2018.8440465
D. Montenegro, M. Bello
Nowadays, distribution planning and operations engineers are gradually considering the use of smart inverters to plan and operate the network in a seamless approach. Smart inverters have the capability of maintaining the distribution system integrity if it is optimally configured with the existing distribution system control device(s). This paper describes the results of combining traditional distribution system Integrated Volt-Var Control (IVVC) with varying smart inverter control functionalities to regulate feeder voltages, reduce line regulator tap operations; while optimizing system losses. The aim of this project was to check the operational impacts of several distribution system control devices with high penetration of connected residential roof -top PVs with smart inverters.
{"title":"Coordinating Control Devices and Smart Inverter Functionalities in the Presence of Variable Weather Conditions","authors":"D. Montenegro, M. Bello","doi":"10.1109/TDC.2018.8440465","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440465","url":null,"abstract":"Nowadays, distribution planning and operations engineers are gradually considering the use of smart inverters to plan and operate the network in a seamless approach. Smart inverters have the capability of maintaining the distribution system integrity if it is optimally configured with the existing distribution system control device(s). This paper describes the results of combining traditional distribution system Integrated Volt-Var Control (IVVC) with varying smart inverter control functionalities to regulate feeder voltages, reduce line regulator tap operations; while optimizing system losses. The aim of this project was to check the operational impacts of several distribution system control devices with high penetration of connected residential roof -top PVs with smart inverters.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"8 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85693987","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 : 2018-04-16DOI: 10.1109/TDC.2018.8440540
Thomas J. Morrell, V. Venkataramanan, A. Srivastava, A. Bose, Chen-Ching Liu
The electric distribution system is becoming more complex with increasing visibility, and a variety of control devices for voltage and power factor control. These advancements provide improved observability of system status and let the operator control the system in more efficient ways. Smart meters are measurement devices that allow the operator to acquire accurate information about the end consumers, and state of the system. Smart meters provide the opportunity to revisit traditional distribution system models in an effort to improve them with more accurate information. Smart meter data enables the creation of time-varying load based distribution system models, enabling testing of various control algorithms. This paper purposes a method for developing a time-series distribution power-flow model using text-based AMI load data which may contain calculation failures. As a test case, a real distribution feeder is modeled in the open source distribution software GridLAB-D, with seasonal loading scenarios. The results are verified by DMS data obtained from the utility. The proposed method does not require GIS data for creating distribution system model. and also provides ways to deal with had data.
{"title":"Modeling of Electric Distribution Feeder Using Smart Meter Data","authors":"Thomas J. Morrell, V. Venkataramanan, A. Srivastava, A. Bose, Chen-Ching Liu","doi":"10.1109/TDC.2018.8440540","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440540","url":null,"abstract":"The electric distribution system is becoming more complex with increasing visibility, and a variety of control devices for voltage and power factor control. These advancements provide improved observability of system status and let the operator control the system in more efficient ways. Smart meters are measurement devices that allow the operator to acquire accurate information about the end consumers, and state of the system. Smart meters provide the opportunity to revisit traditional distribution system models in an effort to improve them with more accurate information. Smart meter data enables the creation of time-varying load based distribution system models, enabling testing of various control algorithms. This paper purposes a method for developing a time-series distribution power-flow model using text-based AMI load data which may contain calculation failures. As a test case, a real distribution feeder is modeled in the open source distribution software GridLAB-D, with seasonal loading scenarios. The results are verified by DMS data obtained from the utility. The proposed method does not require GIS data for creating distribution system model. and also provides ways to deal with had data.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"73 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85991770","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 : 2018-04-16DOI: 10.1109/TDC.2018.8440246
K. Prabakar, A. Pratt, D. Krishnamurthy, A. Maitra
Increasing penetration levels of distributed energy resources are making the deployment of microgrids more feasible. Controllers that operate such microgrids are key to realizing the objectives of the microgrid owner or operator and there is a need to evaluate microgrid controller performance prior to field deployment. This paper describes a controller hardware-in-the-loop and power hardware-in-the-loop microgrid controller test bed that was designed and constructed to evaluate the capabilities of a microgrid controller for a proposed campus microgrid. This paper also presents a test methodology to evaluate microgrid controller functionality, and it describes how the controller was assessed through the application of different test scenarios. Results from the testing are presented to provide insight into the capabilities of the test bed.
{"title":"Hardware-in-the-Loop Test Bed and Test Methodology for Microgrid Controller Evaluation","authors":"K. Prabakar, A. Pratt, D. Krishnamurthy, A. Maitra","doi":"10.1109/TDC.2018.8440246","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440246","url":null,"abstract":"Increasing penetration levels of distributed energy resources are making the deployment of microgrids more feasible. Controllers that operate such microgrids are key to realizing the objectives of the microgrid owner or operator and there is a need to evaluate microgrid controller performance prior to field deployment. This paper describes a controller hardware-in-the-loop and power hardware-in-the-loop microgrid controller test bed that was designed and constructed to evaluate the capabilities of a microgrid controller for a proposed campus microgrid. This paper also presents a test methodology to evaluate microgrid controller functionality, and it describes how the controller was assessed through the application of different test scenarios. Results from the testing are presented to provide insight into the capabilities of the test bed.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"13 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73477062","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 : 2018-04-16DOI: 10.1109/TDC.2018.8440254
K. Ravikumar, A. Srivastava
Fast open line detection plays a critical role in ensuring system survivability and preventing wide-area blackouts. The loss of critical assets, such as transmission lines, should be quickly detected and corrective actions initiated through remedial action schemes to preserve system stability. Disturbances, such as line tripping caused by severe faults or breaker misoperation, can cause oscillations in machine rotors, resulting in power swings that affect power system stability. Quick, accurate open line detection is necessary to initiate automated corrective action in time to minimize system impacts and avoid blackouts. The speed and accuracy of existing open line detection methods limit their ability to take fast corrective control actions. This paper proposes a fast, secure, zero-setting algorithm to detect and declare open line conditions using wide-area synchrophasor measurements. Simulation results based on a real industrial system are presented for various transmission line topologies commonly found in high-voltage networks.
{"title":"Zero-Setting Algorithm for High-Speed Open Line Detection Using Synchrophasors","authors":"K. Ravikumar, A. Srivastava","doi":"10.1109/TDC.2018.8440254","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440254","url":null,"abstract":"Fast open line detection plays a critical role in ensuring system survivability and preventing wide-area blackouts. The loss of critical assets, such as transmission lines, should be quickly detected and corrective actions initiated through remedial action schemes to preserve system stability. Disturbances, such as line tripping caused by severe faults or breaker misoperation, can cause oscillations in machine rotors, resulting in power swings that affect power system stability. Quick, accurate open line detection is necessary to initiate automated corrective action in time to minimize system impacts and avoid blackouts. The speed and accuracy of existing open line detection methods limit their ability to take fast corrective control actions. This paper proposes a fast, secure, zero-setting algorithm to detect and declare open line conditions using wide-area synchrophasor measurements. Simulation results based on a real industrial system are presented for various transmission line topologies commonly found in high-voltage networks.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"51 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88679112","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 : 2018-04-16DOI: 10.1109/TDC.2018.8440334
Chong Wang, Zhaoyu Wang, Shanshan Ma
Load modeling is critical to power system studies. This paper proposes a parameter identification technique for the ZIP load model by leveraging the support vector machine (SVM) approach. The ZIP load model is represented as a linear regression expression. To improve the accuracy of parameter identification, one filter, i.e., Hampel filer, is used to preprocess measurements to reduce noises. The data after noise reduction are used as training data of the regression model, which is handled by the SVM approach. Several case studies show that the SVM with filters can identify the parameters for the static load model with high accuracy.
{"title":"SVM-Based Parameter Identification for Static Load Modeling","authors":"Chong Wang, Zhaoyu Wang, Shanshan Ma","doi":"10.1109/TDC.2018.8440334","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440334","url":null,"abstract":"Load modeling is critical to power system studies. This paper proposes a parameter identification technique for the ZIP load model by leveraging the support vector machine (SVM) approach. The ZIP load model is represented as a linear regression expression. To improve the accuracy of parameter identification, one filter, i.e., Hampel filer, is used to preprocess measurements to reduce noises. The data after noise reduction are used as training data of the regression model, which is handled by the SVM approach. Several case studies show that the SVM with filters can identify the parameters for the static load model with high accuracy.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"9 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2018-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88522828","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 : 2018-04-16DOI: 10.1109/TDC.2018.8440362
Weihang Yan, David Wenzhong Gao, Shuo Huang
In this paper, an islanded microgrid with virtual synchronous generator integration is investigated and virtual synchronous generator dynamic model under dq reference is presented. Moreover, the distributed secondary controllers of microgrid are designed and allocated to each distributed generator by taking advantage of the simple structure of Extremum Seeking algorithm for purpose of adjusting the frequency of microgrid to its nominal value cooperatively during disturbance. The dynamic behavior of overall proposed two-layer system is analyzed. Regarding on frequency changing pattern, modifications is made on variable Extremum Seeking convergence gain and variable virtual synchronous generator inertia constant in order to achieve faster frequency restoration. Finally, simulation results regarding the frequency within microgrid physical network, active power allocation and control among distributed generators are given. Both theoretical analysis and simulation results reveal that the participation of distributed secondary controller recovers the frequency of microgrid to its nominal value quickly even though load disturbance occurs.
{"title":"Distributed Secondary Control of Virtual Synchronous Generator Integrated Microgrid via Extremum Seeking","authors":"Weihang Yan, David Wenzhong Gao, Shuo Huang","doi":"10.1109/TDC.2018.8440362","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440362","url":null,"abstract":"In this paper, an islanded microgrid with virtual synchronous generator integration is investigated and virtual synchronous generator dynamic model under dq reference is presented. Moreover, the distributed secondary controllers of microgrid are designed and allocated to each distributed generator by taking advantage of the simple structure of Extremum Seeking algorithm for purpose of adjusting the frequency of microgrid to its nominal value cooperatively during disturbance. The dynamic behavior of overall proposed two-layer system is analyzed. Regarding on frequency changing pattern, modifications is made on variable Extremum Seeking convergence gain and variable virtual synchronous generator inertia constant in order to achieve faster frequency restoration. Finally, simulation results regarding the frequency within microgrid physical network, active power allocation and control among distributed generators are given. Both theoretical analysis and simulation results reveal that the participation of distributed secondary controller recovers the frequency of microgrid to its nominal value quickly even though load disturbance occurs.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"33 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86223807","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 : 2018-04-16DOI: 10.1109/TDC.2018.8440146
F. Wilches-Bernal, D. Schoenwald, Rui Fan, M. Elizondo, H. Kirkham
A wide-area controller to damp inter-area oscillations in the North American Western Interconnection (WI) by modulating power transfers in a HVDC link is used in this paper to investigate the effects that latencies in its feedback signals have on its performance. This controller uses two feedback measurements to perform its control action. The analysis show that the stabilizing effect of the controller in transient stability and small signal stability is compromised as the feedback measurements experience higher delays. The results show that one of the feedback signals can tolerate more delay than the other. The analysis was performed with Bode plots and time domain simulations on a reduced order model of the WI from which a linear version was obtained.
{"title":"Analysis of the Effect of Communication Latencies on HVDC-Based Damping Control","authors":"F. Wilches-Bernal, D. Schoenwald, Rui Fan, M. Elizondo, H. Kirkham","doi":"10.1109/TDC.2018.8440146","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440146","url":null,"abstract":"A wide-area controller to damp inter-area oscillations in the North American Western Interconnection (WI) by modulating power transfers in a HVDC link is used in this paper to investigate the effects that latencies in its feedback signals have on its performance. This controller uses two feedback measurements to perform its control action. The analysis show that the stabilizing effect of the controller in transient stability and small signal stability is compromised as the feedback measurements experience higher delays. The results show that one of the feedback signals can tolerate more delay than the other. The analysis was performed with Bode plots and time domain simulations on a reduced order model of the WI from which a linear version was obtained.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"15 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91135216","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 : 2018-04-16DOI: 10.1109/TDC.2018.8440436
David M. Rosewater, Q. Nguyen, S. Santoso
Power systems can become unstable under transient periods such as short-circuit faults, leading to equipment damage and large scale blackouts. Power system stabilizers (PSS) can be designed to improve the stability of generators by quickly regulating the exciter field voltage to damp the swings of generator rotor angle and speed. The stability achieved through exciter field voltage control can be further improved with a relatively small, fast responding energy storage system (ESS) connected at the terminals of the generator that enables electrical power damping. PSS are designed and studied using a single-machine infinite-bus (SMIB) model. In this paper, we present a comprehensive optimal-control design for a flexible ac synchronous generator PSS using both exciter field voltage and ESS control including estimation of unmeasurable states. The controller is designed to minimize disturbances in rotor frequency and angle, and thereby improve stability. The design process is based on a linear quadratic regulator of the SMIB model with a test system linearized about different operating frequencies in the range 10 Hz to 60 Hz. The optimal performance of the PSS is demonstrated along with the resulting stability improvement.
{"title":"Optimal Field Voltage and Energy Storage Control for Stabilizing Synchronous Generators on Flexible AC Transmission Systems","authors":"David M. Rosewater, Q. Nguyen, S. Santoso","doi":"10.1109/TDC.2018.8440436","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440436","url":null,"abstract":"Power systems can become unstable under transient periods such as short-circuit faults, leading to equipment damage and large scale blackouts. Power system stabilizers (PSS) can be designed to improve the stability of generators by quickly regulating the exciter field voltage to damp the swings of generator rotor angle and speed. The stability achieved through exciter field voltage control can be further improved with a relatively small, fast responding energy storage system (ESS) connected at the terminals of the generator that enables electrical power damping. PSS are designed and studied using a single-machine infinite-bus (SMIB) model. In this paper, we present a comprehensive optimal-control design for a flexible ac synchronous generator PSS using both exciter field voltage and ESS control including estimation of unmeasurable states. The controller is designed to minimize disturbances in rotor frequency and angle, and thereby improve stability. The design process is based on a linear quadratic regulator of the SMIB model with a test system linearized about different operating frequencies in the range 10 Hz to 60 Hz. The optimal performance of the PSS is demonstrated along with the resulting stability improvement.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"1 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77491517","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 : 2018-04-16DOI: 10.1109/TDC.2018.8440245
J. Kluss, D. Wallace, W. Whittington, M. Stafford
A specific type of cap and pin suspension insulator has resulted in a number of pole fires while in service. To identify the underlying failure mechanism, electrical, mechanical, and material quality tests were performed. Despite appearing visually in good condition, and retaining higher than required mechanical strength, some samples were highly conductive at relatively low voltages. Porosity tests, resistance, power factor, and partial discharge measurements were inconclusive in defining the cause of failure prompting further investigation.
{"title":"Failure Investigation on Field Aged Porcelain Suspension Insulators","authors":"J. Kluss, D. Wallace, W. Whittington, M. Stafford","doi":"10.1109/TDC.2018.8440245","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440245","url":null,"abstract":"A specific type of cap and pin suspension insulator has resulted in a number of pole fires while in service. To identify the underlying failure mechanism, electrical, mechanical, and material quality tests were performed. Despite appearing visually in good condition, and retaining higher than required mechanical strength, some samples were highly conductive at relatively low voltages. Porosity tests, resistance, power factor, and partial discharge measurements were inconclusive in defining the cause of failure prompting further investigation.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"8 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2018-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75080104","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：