Pub Date : 2017-10-01DOI: 10.1109/EPEC.2017.8286227
N. Jacob, S. Sherif, B. Kordi
Samples of plain Kraft cellulose paper, normally used in power transformer winding turn insulation, were thermally aged in controlled laboratory experiments to obtain a sample set with varying levels of thermal deterioration. Microscopy images from the samples were analyzed using a texture analysis method where wavelet energies at different decomposition levels were calculated. Analysis of our results indicates that as the paper fibers breakdown, the wavelet energies of the texture details are reduced in value in proportion to this deterioration in the paper.
{"title":"Quantification of changes in surface texture of thermally-aged kraft paper using orthogonal wavelets","authors":"N. Jacob, S. Sherif, B. Kordi","doi":"10.1109/EPEC.2017.8286227","DOIUrl":"https://doi.org/10.1109/EPEC.2017.8286227","url":null,"abstract":"Samples of plain Kraft cellulose paper, normally used in power transformer winding turn insulation, were thermally aged in controlled laboratory experiments to obtain a sample set with varying levels of thermal deterioration. Microscopy images from the samples were analyzed using a texture analysis method where wavelet energies at different decomposition levels were calculated. Analysis of our results indicates that as the paper fibers breakdown, the wavelet energies of the texture details are reduced in value in proportion to this deterioration in the paper.","PeriodicalId":141250,"journal":{"name":"2017 IEEE Electrical Power and Energy Conference (EPEC)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129793322","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 : 2017-10-01DOI: 10.1109/EPEC.2017.8286154
Mohammadali Taheri, Pooya Taheri
The goal of this paper is to study the feasibility of heat recovery from Mashhad power plant's exhaust gas for the heating and ventilation of a visitor facility. The first stage of this research involves gathering information and technical documents: technical specifications of gas turbines, physical and chemical analysis of exhaust gas, construction layout of the utility, and maintenance and overhaul schedules. The next stages involve calculating the dew point of the exhaust gas, assessing the gas turbines' remaining lifetime, calculating the total potential heat energy that can be recovered, considerations on selecting the carrier fluid, and finally, the economic feasibility studies. This study demonstrates the feasibility of this project as having a high potential for return of investment in a short period of time.
{"title":"Feasibility study of cogeneration for a gas power plant","authors":"Mohammadali Taheri, Pooya Taheri","doi":"10.1109/EPEC.2017.8286154","DOIUrl":"https://doi.org/10.1109/EPEC.2017.8286154","url":null,"abstract":"The goal of this paper is to study the feasibility of heat recovery from Mashhad power plant's exhaust gas for the heating and ventilation of a visitor facility. The first stage of this research involves gathering information and technical documents: technical specifications of gas turbines, physical and chemical analysis of exhaust gas, construction layout of the utility, and maintenance and overhaul schedules. The next stages involve calculating the dew point of the exhaust gas, assessing the gas turbines' remaining lifetime, calculating the total potential heat energy that can be recovered, considerations on selecting the carrier fluid, and finally, the economic feasibility studies. This study demonstrates the feasibility of this project as having a high potential for return of investment in a short period of time.","PeriodicalId":141250,"journal":{"name":"2017 IEEE Electrical Power and Energy Conference (EPEC)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126582513","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 : 2017-10-01DOI: 10.1109/EPEC.2017.8286158
Shengjun Huang, V. Dinavahi
Achieving high solution efficiency for alternating current power flow (ACPF) analysis from high-performance computing (HPC) architecture is a leading and important challenge in power system analytics and computation. This paper investigates the performance of the fast decoupled (FD) method, which is based on the direct linear solver and implemented on the graphics processing unit (GPU), for the solution of ACPF. Implementation platforms, linear equations solution strategies, data storage formats, and fill-in reduction algorithms are compared and discussed on five benchmark systems ranging from 300 to 13,659 buses. Within the GPU's compute unified device architecture (CUDA) environment, the shortest ACPF solution time for the largest test case is 0.313s, which is 4.16 x faster than its Matlab counterpart.
{"title":"Performance analysis of GPU-accelerated fast decoupled power flow using direct linear solver","authors":"Shengjun Huang, V. Dinavahi","doi":"10.1109/EPEC.2017.8286158","DOIUrl":"https://doi.org/10.1109/EPEC.2017.8286158","url":null,"abstract":"Achieving high solution efficiency for alternating current power flow (ACPF) analysis from high-performance computing (HPC) architecture is a leading and important challenge in power system analytics and computation. This paper investigates the performance of the fast decoupled (FD) method, which is based on the direct linear solver and implemented on the graphics processing unit (GPU), for the solution of ACPF. Implementation platforms, linear equations solution strategies, data storage formats, and fill-in reduction algorithms are compared and discussed on five benchmark systems ranging from 300 to 13,659 buses. Within the GPU's compute unified device architecture (CUDA) environment, the shortest ACPF solution time for the largest test case is 0.313s, which is 4.16 x faster than its Matlab counterpart.","PeriodicalId":141250,"journal":{"name":"2017 IEEE Electrical Power and Energy Conference (EPEC)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126925455","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 : 2017-10-01DOI: 10.1109/EPEC.2017.8286168
Amr Mohamed, Antoine Lesage-Landry, Joshua A. Taylor
Utilizing residential Thermostatically Controlled Loads (TCLs) for demand response stands to offer a more economical and environmentally friendly alternative to procuring energy storage and generation facilities for grid ancillary services. We use the adversarial multi-armed bandit framework to learn the signal response of TCLs and determine which TCLs to activate for demand response in real-time. We demonstrate the performance of our proposed approach by invoking theoretical bounds on the performance of an Exp3.M-based algorithm, and comparing the performance with a greedy algorithm. A sub-linear regret shows that the algorithm is able to learn and identify high-performing TCLs, and activate them more frequently as more information is acquired about the TCLs' signal response.
{"title":"Dispatching thermostatically controlled loads for frequency regulation using adversarial multi-armed bandits","authors":"Amr Mohamed, Antoine Lesage-Landry, Joshua A. Taylor","doi":"10.1109/EPEC.2017.8286168","DOIUrl":"https://doi.org/10.1109/EPEC.2017.8286168","url":null,"abstract":"Utilizing residential Thermostatically Controlled Loads (TCLs) for demand response stands to offer a more economical and environmentally friendly alternative to procuring energy storage and generation facilities for grid ancillary services. We use the adversarial multi-armed bandit framework to learn the signal response of TCLs and determine which TCLs to activate for demand response in real-time. We demonstrate the performance of our proposed approach by invoking theoretical bounds on the performance of an Exp3.M-based algorithm, and comparing the performance with a greedy algorithm. A sub-linear regret shows that the algorithm is able to learn and identify high-performing TCLs, and activate them more frequently as more information is acquired about the TCLs' signal response.","PeriodicalId":141250,"journal":{"name":"2017 IEEE Electrical Power and Energy Conference (EPEC)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127324387","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 : 2017-10-01DOI: 10.1109/EPEC.2017.8286162
F. Fang, R. Karki
Hydro-electric generation is often energy limited due to insufficient river inflow during dry seasons. This can result in significant adverse impact on long term system adequacy. Most hydro plants are run-of-river types that have small head pond with limited storage capability to manage available energy to follow the demand variation. The opportunity for reliability enhancement of a hydro-dominant system through diurnal water management with the limited storage needs to be properly investigated. This paper presents analytical reliability models of head pond and power generation to recognize energy storage and the magnitude and time-shift of output power to match the diurnal load profile during energy limited periods of the year. The developed models are applied to the IEEE Reliability Test System that is modified to create a hydro dominant system. The impact on system reliability of diurnal energy management and the number plants involved in energy management are investigated in the study.
{"title":"Reliability assessment of hydro dominant systems with diurnal energy management","authors":"F. Fang, R. Karki","doi":"10.1109/EPEC.2017.8286162","DOIUrl":"https://doi.org/10.1109/EPEC.2017.8286162","url":null,"abstract":"Hydro-electric generation is often energy limited due to insufficient river inflow during dry seasons. This can result in significant adverse impact on long term system adequacy. Most hydro plants are run-of-river types that have small head pond with limited storage capability to manage available energy to follow the demand variation. The opportunity for reliability enhancement of a hydro-dominant system through diurnal water management with the limited storage needs to be properly investigated. This paper presents analytical reliability models of head pond and power generation to recognize energy storage and the magnitude and time-shift of output power to match the diurnal load profile during energy limited periods of the year. The developed models are applied to the IEEE Reliability Test System that is modified to create a hydro dominant system. The impact on system reliability of diurnal energy management and the number plants involved in energy management are investigated in the study.","PeriodicalId":141250,"journal":{"name":"2017 IEEE Electrical Power and Energy Conference (EPEC)","volume":"300 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127355505","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 : 2017-10-01DOI: 10.1109/EPEC.2017.8286204
Z. Hasan, M. El-Hawary
This paper proposes a probabilistic model to the load reduction (LR) as demand side management (DSM) method for the economic dispatch problem in smart grid network (SGED). The objective is to drive the mathematical model of the probabilistic model and the problem. Then solve the problem using Black Hole optimization algorithm for two Test systems: three generation units with valve point effect and six generation units with prohibited operation zone and ramp rate limits.
{"title":"Load reduction probabilistic model for smart grid network economic dispatch problem","authors":"Z. Hasan, M. El-Hawary","doi":"10.1109/EPEC.2017.8286204","DOIUrl":"https://doi.org/10.1109/EPEC.2017.8286204","url":null,"abstract":"This paper proposes a probabilistic model to the load reduction (LR) as demand side management (DSM) method for the economic dispatch problem in smart grid network (SGED). The objective is to drive the mathematical model of the probabilistic model and the problem. Then solve the problem using Black Hole optimization algorithm for two Test systems: three generation units with valve point effect and six generation units with prohibited operation zone and ramp rate limits.","PeriodicalId":141250,"journal":{"name":"2017 IEEE Electrical Power and Energy Conference (EPEC)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134537347","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 paper proposes a novel efficient tri-state boost converter. It introduces a state of zero inductor voltage to reduce the inductor charging and discharging time. Then, the core loss is reduced due to reducing the inductor ripple current. In addition, by adding the auxiliary inductor, the current of the freewheeling diode naturally drops to zero, which eliminates the reverse recovery loss. Thus, the proposed converter achieves a higher efficiency and faster dynamic response (absence of right-half-plane zero) compared with the classical boost converter. First, the structure and operation principle of the proposed converter is presented in detail. Then, the main losses of the converter are analyzed. Finally, simulation and experimental results prove the effectiveness of the theoretical analysis.
{"title":"A novel efficient tri-state boost converter","authors":"Hua Han, R. Tan, Jian Yang, Hui Wang, Sijie Ning, Mengtian Shen","doi":"10.1109/EPEC.2017.8286197","DOIUrl":"https://doi.org/10.1109/EPEC.2017.8286197","url":null,"abstract":"The paper proposes a novel efficient tri-state boost converter. It introduces a state of zero inductor voltage to reduce the inductor charging and discharging time. Then, the core loss is reduced due to reducing the inductor ripple current. In addition, by adding the auxiliary inductor, the current of the freewheeling diode naturally drops to zero, which eliminates the reverse recovery loss. Thus, the proposed converter achieves a higher efficiency and faster dynamic response (absence of right-half-plane zero) compared with the classical boost converter. First, the structure and operation principle of the proposed converter is presented in detail. Then, the main losses of the converter are analyzed. Finally, simulation and experimental results prove the effectiveness of the theoretical analysis.","PeriodicalId":141250,"journal":{"name":"2017 IEEE Electrical Power and Energy Conference (EPEC)","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134258302","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 : 2017-10-01DOI: 10.1109/EPEC.2017.8286213
J. Pannell, Olivier Larocque, R. Gokaraju
This paper develops a method for finding optimum control parameters for Type III DFIG wind generators using electro-magnetic transient simulations. The optimization is performed on the eight time constant variables within a supplemental damping controller being used for protection against SSCI events in a Type III DFIG based windfarm. For validation and verification of the research results, a wind farm consisting of 150–3 MW Type III Doubly Fed Induction Generators (DFIG) connected to a stiff voltage source through a 240 km transmission line was modeled in PSCAD/EMTDC. After completion of the initial design of the supplementary damping controller, the results are further refined using a non-linear time domain simplex optimization (multi-run) process within the electromagnetic transient simulations.
{"title":"Simplex optimization procedure for tuning damping controller parameters for Type III DFIG wind generators","authors":"J. Pannell, Olivier Larocque, R. Gokaraju","doi":"10.1109/EPEC.2017.8286213","DOIUrl":"https://doi.org/10.1109/EPEC.2017.8286213","url":null,"abstract":"This paper develops a method for finding optimum control parameters for Type III DFIG wind generators using electro-magnetic transient simulations. The optimization is performed on the eight time constant variables within a supplemental damping controller being used for protection against SSCI events in a Type III DFIG based windfarm. For validation and verification of the research results, a wind farm consisting of 150–3 MW Type III Doubly Fed Induction Generators (DFIG) connected to a stiff voltage source through a 240 km transmission line was modeled in PSCAD/EMTDC. After completion of the initial design of the supplementary damping controller, the results are further refined using a non-linear time domain simplex optimization (multi-run) process within the electromagnetic transient simulations.","PeriodicalId":141250,"journal":{"name":"2017 IEEE Electrical Power and Energy Conference (EPEC)","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133085013","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 : 2017-10-01DOI: 10.1109/EPEC.2017.8286210
Zhaoyu Qin, Chaohai Zhang, Yu Zheng, Wenjun Zhou, Shuai Yang
SF6/N2 mixture has been used in gas insulation transmission lines (GIL) for years in order to reduce the use of SF6 gas in electrical industry. Considering the insulation performance and environmental effect, the SF6/N2 mixture in practical use of GIL is advised to ensure SF6 content as low as possible, which can reduce the use of SF6 to the most. However, the applicable lowest content of SF6 in the mixture still remains unknown. In order to investigate the optimization of SF6/N2 mixture as an alternative choice to SF6, this paper reports the insulation properties of the mixture with SF6 content from 10% to 40% and the pressure of 0.4MPa to 0.7MPa under 50Hz power frequency voltage, which can reach equal insulation performance to SF6 at 0.4MPa∼0.5MPa. The rod-plate and ball-plate electrode models are adopted in the voltage breakdown experiment, the sensitivity to uneven electrical field is obtained through the experimental results. The experimental results indicate that, in the absolute pressure range of 0.4MPa to 0.7MPa, the breakdown voltage of SF6/N2 increases linearly with gas pressure and presents a power function with SF6 content, the power index decreasing as filling pressure becomes higher. The filling pressure should increase 1.4∼1.8 times to reach similar insulation performance with SF6, and different content of SF6 is discussed.
{"title":"Insulation properties of SF6/N2 gas mixtures under high pressure and low ratio","authors":"Zhaoyu Qin, Chaohai Zhang, Yu Zheng, Wenjun Zhou, Shuai Yang","doi":"10.1109/EPEC.2017.8286210","DOIUrl":"https://doi.org/10.1109/EPEC.2017.8286210","url":null,"abstract":"SF6/N2 mixture has been used in gas insulation transmission lines (GIL) for years in order to reduce the use of SF6 gas in electrical industry. Considering the insulation performance and environmental effect, the SF6/N2 mixture in practical use of GIL is advised to ensure SF6 content as low as possible, which can reduce the use of SF6 to the most. However, the applicable lowest content of SF6 in the mixture still remains unknown. In order to investigate the optimization of SF6/N2 mixture as an alternative choice to SF6, this paper reports the insulation properties of the mixture with SF6 content from 10% to 40% and the pressure of 0.4MPa to 0.7MPa under 50Hz power frequency voltage, which can reach equal insulation performance to SF6 at 0.4MPa∼0.5MPa. The rod-plate and ball-plate electrode models are adopted in the voltage breakdown experiment, the sensitivity to uneven electrical field is obtained through the experimental results. The experimental results indicate that, in the absolute pressure range of 0.4MPa to 0.7MPa, the breakdown voltage of SF6/N2 increases linearly with gas pressure and presents a power function with SF6 content, the power index decreasing as filling pressure becomes higher. The filling pressure should increase 1.4∼1.8 times to reach similar insulation performance with SF6, and different content of SF6 is discussed.","PeriodicalId":141250,"journal":{"name":"2017 IEEE Electrical Power and Energy Conference (EPEC)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122394813","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 : 2017-10-01DOI: 10.1109/EPEC.2017.8286138
O. Gupta, M. Tripathy, V. Sood
The role of shunt Flexible AC transmission System (FACTS) devices is to improve voltage profile. However, in the presence of Shunt FACTS Devices (SFDs), protection schemes may incorrectly operate as SFDs inject reactive power in the line. This study presents an Imaginary component of Virtual Fault Impedance (IVFI) based improved relaying for the transmission line in the presence of SFD which is immune to large variations in source impedance. During normal operation or during an external fault, the magnitude of IVFI is very large, on the other hand, during an internal fault, the magnitude of IVFI is either zero or very small. The proposed scheme can be used to detect the internal fault and to classify fault type and it is applicable to uncompensated transmission lines also. The EMTDC/PSCAD simulations are carried out to investigate the performance of the proposed scheme. The scheme is found to be selective, robust, and accurate for all possible faulty conditions, for different types of SFDs with different compensation levels and for high resistance faults.
{"title":"Digital relaying scheme for protection of shunt-compensated transmission lines","authors":"O. Gupta, M. Tripathy, V. Sood","doi":"10.1109/EPEC.2017.8286138","DOIUrl":"https://doi.org/10.1109/EPEC.2017.8286138","url":null,"abstract":"The role of shunt Flexible AC transmission System (FACTS) devices is to improve voltage profile. However, in the presence of Shunt FACTS Devices (SFDs), protection schemes may incorrectly operate as SFDs inject reactive power in the line. This study presents an Imaginary component of Virtual Fault Impedance (IVFI) based improved relaying for the transmission line in the presence of SFD which is immune to large variations in source impedance. During normal operation or during an external fault, the magnitude of IVFI is very large, on the other hand, during an internal fault, the magnitude of IVFI is either zero or very small. The proposed scheme can be used to detect the internal fault and to classify fault type and it is applicable to uncompensated transmission lines also. The EMTDC/PSCAD simulations are carried out to investigate the performance of the proposed scheme. The scheme is found to be selective, robust, and accurate for all possible faulty conditions, for different types of SFDs with different compensation levels and for high resistance faults.","PeriodicalId":141250,"journal":{"name":"2017 IEEE Electrical Power and Energy Conference (EPEC)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121157388","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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