Pub Date : 2016-07-17DOI: 10.1109/PESGM.2016.7741793
C. Yan, Baohui Zhang, Z. Hao, Song Zhang
Power transformers play a very critical role in electrical energy transmission. Abnormal performance of transformers would seriously affect the reliability and stability of power system. Non-electrical gas relays are usually used as a main protection of power transformers. Indeed, due to the inherent defects, the gas relay misjudgments happen every year across the world. Given this background, this paper employs a theoretical model and its simulation method to study the relationship between electrical faults and non-electrical pressure variations inside the tank. Based on the essence difference of the pressure characteristics among the internal faults, external faults and normal running condition, a novel transformer protection principle is proposed. Numerical test has indicated that the proposed protection is able to reliably clear the transformer internal faults, even the single-turn fault or other weak faults.
{"title":"A novel digital non-electrical protection for power transformer based on internal pressure characteristics","authors":"C. Yan, Baohui Zhang, Z. Hao, Song Zhang","doi":"10.1109/PESGM.2016.7741793","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741793","url":null,"abstract":"Power transformers play a very critical role in electrical energy transmission. Abnormal performance of transformers would seriously affect the reliability and stability of power system. Non-electrical gas relays are usually used as a main protection of power transformers. Indeed, due to the inherent defects, the gas relay misjudgments happen every year across the world. Given this background, this paper employs a theoretical model and its simulation method to study the relationship between electrical faults and non-electrical pressure variations inside the tank. Based on the essence difference of the pressure characteristics among the internal faults, external faults and normal running condition, a novel transformer protection principle is proposed. Numerical test has indicated that the proposed protection is able to reliably clear the transformer internal faults, even the single-turn fault or other weak faults.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"47 11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115945975","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741105
C. El‐Bayeh, I. Mougharbel, M. Saad, A. Chandra, S. Lefebvre, D. Asber, L. Lenoir
Many studies have concentrated on how to optimize the size and placement of Parking Lots (PLs) on a distribution network. Within this context, this study consists of presenting a systematic approach for sizing the PL in terms of number of simultaneously plugged-in vehicles. This approach is original since it takes into account the loads' profile on the bus where the PL is connected (it is valid for any load profile on the bus), the PL manager benefits and the vehicles' owners requirements. Multiple technical constraints are respected, those imposed by the PL infrastructure and those related to the distribution network. A mathematical model and an algorithm are developed for this purpose using MATLAB.
{"title":"A novel approach for sizing electric vehicles Parking Lot located at any bus on a network","authors":"C. El‐Bayeh, I. Mougharbel, M. Saad, A. Chandra, S. Lefebvre, D. Asber, L. Lenoir","doi":"10.1109/PESGM.2016.7741105","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741105","url":null,"abstract":"Many studies have concentrated on how to optimize the size and placement of Parking Lots (PLs) on a distribution network. Within this context, this study consists of presenting a systematic approach for sizing the PL in terms of number of simultaneously plugged-in vehicles. This approach is original since it takes into account the loads' profile on the bus where the PL is connected (it is valid for any load profile on the bus), the PL manager benefits and the vehicles' owners requirements. Multiple technical constraints are respected, those imposed by the PL infrastructure and those related to the distribution network. A mathematical model and an algorithm are developed for this purpose using MATLAB.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114807472","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7742013
Abhishek Banerjee, N. Chaudhuri
This paper demonstrates robust damping of interarea oscillations in an AC-Multiterminal DC (MTDC) grid following major contingencies like the outage of a converter pole and line outage. Damping controller design based on H∞ mixed-sensitivity formulation in the Linear Matrix Inequality (LMI) framework has been performed. Emphasis has been placed on achieving robustness in the design by incorporating proper weighing filters for disturbance rejection and control energy minimization. The proposed controller uses feedback signals from remote locations and modulates the real power reference of two converter poles in a converter station of the asymmetric bipolar MTDC grid, which is integrated with AC systems. A 6-machine 3-area system and a 16-machine, 5-area system were used as the AC test systems. Robustness in damping performance in case of converter outage and AC line outage was successfully achieved by the designed controllers in both the test systems.
{"title":"Robust Damping of iNTER-AREA oSCILLATIONS in AC-MTDC grids using H∞ Mixed-sensitivity approach","authors":"Abhishek Banerjee, N. Chaudhuri","doi":"10.1109/PESGM.2016.7742013","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7742013","url":null,"abstract":"This paper demonstrates robust damping of interarea oscillations in an AC-Multiterminal DC (MTDC) grid following major contingencies like the outage of a converter pole and line outage. Damping controller design based on H∞ mixed-sensitivity formulation in the Linear Matrix Inequality (LMI) framework has been performed. Emphasis has been placed on achieving robustness in the design by incorporating proper weighing filters for disturbance rejection and control energy minimization. The proposed controller uses feedback signals from remote locations and modulates the real power reference of two converter poles in a converter station of the asymmetric bipolar MTDC grid, which is integrated with AC systems. A 6-machine 3-area system and a 16-machine, 5-area system were used as the AC test systems. Robustness in damping performance in case of converter outage and AC line outage was successfully achieved by the designed controllers in both the test systems.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114641968","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741795
C. Yan, Z. Hao, Yiqi Dang, Baohui Zhang, T. Zheng, Song Zhang
Large oil-immersed power transformers always have the gas relay equipped between the main tank and conservator. However, due to the inherent defects, the gas relay malfunction caused by external faults happens occasionally all over the world, which jeopardizes the safe operation of bulk power systems. In order to explore the oil flow characteristics inside the pipe during external short circuit faults, we built the transient oil flow measurement system on the 40 MVA/110 kV power transformer, and carried out 34 external short circuit fault test campaigns. The test results confirmed that the deformation and vibration of transformer windings caused by the short circuit current would lead to the oil flow surge through the pipe. The surge appears with a long time delay up to hundreds of milliseconds due to the liquid inertia. The test also shows that both the fault severity and location would affect the oil flow surge.
{"title":"Oil flow surge test for 110kV power transformer during external short circuit faults","authors":"C. Yan, Z. Hao, Yiqi Dang, Baohui Zhang, T. Zheng, Song Zhang","doi":"10.1109/PESGM.2016.7741795","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741795","url":null,"abstract":"Large oil-immersed power transformers always have the gas relay equipped between the main tank and conservator. However, due to the inherent defects, the gas relay malfunction caused by external faults happens occasionally all over the world, which jeopardizes the safe operation of bulk power systems. In order to explore the oil flow characteristics inside the pipe during external short circuit faults, we built the transient oil flow measurement system on the 40 MVA/110 kV power transformer, and carried out 34 external short circuit fault test campaigns. The test results confirmed that the deformation and vibration of transformer windings caused by the short circuit current would lead to the oil flow surge through the pipe. The surge appears with a long time delay up to hundreds of milliseconds due to the liquid inertia. The test also shows that both the fault severity and location would affect the oil flow surge.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114697108","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741615
Yi Zhao, Chao Lu, Peng Li, Liang Tu
With the economic growth and the renewable energy integration increase, the weakly damped low frequency oscillation has become a major threat to the system stability in China's interconnected power systems. In this paper, some practical work on the applications of synchro-phasor measurement techniques in the field of wide area damping control are presented. The design, implementation and commission of the adaptive wide-area damping control (WADC) system through the modulations of multiple HVDC links and generator exciters are elaborated respectively. Two different adaptive control approaches, i.e., Prony-based and Mode-free Adaptive Control (MFAC), are implemented to adapt to the system change. In addition, time delay and coordination requirements are also considered in the design procedure. The WADC-HVDC system has been commissioned in the practical China Southern Grid (CSG). The field test results show that the coordinated WADC-HVDC system can effectively increase the damping ratios and power transfer capacity. WADC system that regulating the generator exciters are also implemented in CSG and Central China Grid (CCG) to increase the system stability. The performance has been verified via digital simulations conducted in CSG and CCG.
{"title":"Applications of wide-area adaptive HVDC and generator damping control in Chinese power grids","authors":"Yi Zhao, Chao Lu, Peng Li, Liang Tu","doi":"10.1109/PESGM.2016.7741615","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741615","url":null,"abstract":"With the economic growth and the renewable energy integration increase, the weakly damped low frequency oscillation has become a major threat to the system stability in China's interconnected power systems. In this paper, some practical work on the applications of synchro-phasor measurement techniques in the field of wide area damping control are presented. The design, implementation and commission of the adaptive wide-area damping control (WADC) system through the modulations of multiple HVDC links and generator exciters are elaborated respectively. Two different adaptive control approaches, i.e., Prony-based and Mode-free Adaptive Control (MFAC), are implemented to adapt to the system change. In addition, time delay and coordination requirements are also considered in the design procedure. The WADC-HVDC system has been commissioned in the practical China Southern Grid (CSG). The field test results show that the coordinated WADC-HVDC system can effectively increase the damping ratios and power transfer capacity. WADC system that regulating the generator exciters are also implemented in CSG and Central China Grid (CCG) to increase the system stability. The performance has been verified via digital simulations conducted in CSG and CCG.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114956179","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741952
Y. Yasaei, M. Hayat, A. Mammoli
The ability of distribution feeder microgrids to operate as a controllable entity and participate in system-level services is assessed in this paper. The concept of distribution feeder microgrid is introduced. A control mechanism that fits this architecture and fulfills performance criteria as well as stability requirements is discussed in detail. Distribution feeder microgrids when equipped with the proposed control mechanism is shown to have the potential for increasing the heterogeneity of generation-mix and unveiling the hidden capacity of under-utilized resources that can be used in essential power system services. Simulation results verify the envisioned advantages of the application.
{"title":"Response of distribution feeder microgrids to system-level reserve requests","authors":"Y. Yasaei, M. Hayat, A. Mammoli","doi":"10.1109/PESGM.2016.7741952","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741952","url":null,"abstract":"The ability of distribution feeder microgrids to operate as a controllable entity and participate in system-level services is assessed in this paper. The concept of distribution feeder microgrid is introduced. A control mechanism that fits this architecture and fulfills performance criteria as well as stability requirements is discussed in detail. Distribution feeder microgrids when equipped with the proposed control mechanism is shown to have the potential for increasing the heterogeneity of generation-mix and unveiling the hidden capacity of under-utilized resources that can be used in essential power system services. Simulation results verify the envisioned advantages of the application.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115029179","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741942
Y. Y. Chen, J. L. Liao, G. Chang, L. Hsu, Y. Li, H. J. Lu
This paper presents the implementation of power quality (PQ) analysis platform that can access different venders' PQ meter data being translated to Power Quality Data Interchange Format (PQDIF) files and view the data through a LabVIEW-based graphical user interface. The implemented platform also can manage the retrieved PQ data in a customized database. Performance tests show that the implemented system can meet the PQ measurement requirements for smart grid applications.
{"title":"Applying IEEE standard 1159.3 for Power Quality analysis platform implementation","authors":"Y. Y. Chen, J. L. Liao, G. Chang, L. Hsu, Y. Li, H. J. Lu","doi":"10.1109/PESGM.2016.7741942","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741942","url":null,"abstract":"This paper presents the implementation of power quality (PQ) analysis platform that can access different venders' PQ meter data being translated to Power Quality Data Interchange Format (PQDIF) files and view the data through a LabVIEW-based graphical user interface. The implemented platform also can manage the retrieved PQ data in a customized database. Performance tests show that the implemented system can meet the PQ measurement requirements for smart grid applications.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116888861","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741407
Jian Zhao, C. Wan, Zhao Xu, Jiayong Li
With increasingly widespread utilization of photovoltaic (PV) systems, the stochastic characteristics of the PV generation may bring new challenges to security and reliability of the power system operation. This paper proposes a novel spinning reserve requirement optimization model considering the impacts of large-scale photovoltaic generation penetration. The effects of forecast error of PV generation output on the energy not supplied are taken into account in the proposed model. The power system spinning reserve is optimized using a benefit/cost analysis approach to coordinate the costs of generation operation, and the costs of the expected energy not supplied (EENS). The proposed model is illustrated using IEEE reliability test system (RTS-96). Numerical results systematically demonstrate the increase of scheduled spinning reserve and the reduction of EENS via the application of the proposed model. The penetration levels of PV generation in power systems are symmetrically analyzed for future implementation of the proposed model.
{"title":"Impacts of large-scale photovoltaic generation penetration on power system spinning reserve allocation","authors":"Jian Zhao, C. Wan, Zhao Xu, Jiayong Li","doi":"10.1109/PESGM.2016.7741407","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741407","url":null,"abstract":"With increasingly widespread utilization of photovoltaic (PV) systems, the stochastic characteristics of the PV generation may bring new challenges to security and reliability of the power system operation. This paper proposes a novel spinning reserve requirement optimization model considering the impacts of large-scale photovoltaic generation penetration. The effects of forecast error of PV generation output on the energy not supplied are taken into account in the proposed model. The power system spinning reserve is optimized using a benefit/cost analysis approach to coordinate the costs of generation operation, and the costs of the expected energy not supplied (EENS). The proposed model is illustrated using IEEE reliability test system (RTS-96). Numerical results systematically demonstrate the increase of scheduled spinning reserve and the reduction of EENS via the application of the proposed model. The penetration levels of PV generation in power systems are symmetrically analyzed for future implementation of the proposed model.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"118 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116010739","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741708
Rahul Kadavil, T. Hansen, S. Suryanarayanan
Performing co-simulation studies on transmission and distribution systems software environments requires linking the transmission system elements in the former with highly detailed distribution network models and probabilistic load models in the latter. This paper presents a two-step algorithm for: (i) creating a scalable distribution system in a bottom-up approach to match the connected load at the transmission system bus; and (ii) populating the distribution system with active power loads possessing time varying load profiles. We demonstrate an application of the algorithm by creating a detailed distribution topology populated with residential loads expanded from a selected transmission node in a standard test system. All codes are written using the Python coding environment.
{"title":"An algorithmic approach for creating diverse stochastic feeder datasets for power systems co-simulations","authors":"Rahul Kadavil, T. Hansen, S. Suryanarayanan","doi":"10.1109/PESGM.2016.7741708","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741708","url":null,"abstract":"Performing co-simulation studies on transmission and distribution systems software environments requires linking the transmission system elements in the former with highly detailed distribution network models and probabilistic load models in the latter. This paper presents a two-step algorithm for: (i) creating a scalable distribution system in a bottom-up approach to match the connected load at the transmission system bus; and (ii) populating the distribution system with active power loads possessing time varying load profiles. We demonstrate an application of the algorithm by creating a detailed distribution topology populated with residential loads expanded from a selected transmission node in a standard test system. All codes are written using the Python coding environment.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116175082","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741829
S. Kulkarni, M. Parimi, S. Wagh, N. Singh
Knowledge of a potential function is of prime importance in stability analysis of systems. In mechanical systems, energy is considered as potential function. Passivity based methods in literature aim in finding potential function, which may prove unsuccessful for certain class of systems e.g. biological systems. Unfortunately, no general rules exist for the construction of a Lyapunov function, so expertise and intuition of the designer on the specific system is required to define a candidate function. Present paper proposes a systematic method to generate a potential function after decomposing a drift vector field representing a general dynamical system. The method finds application in lossy multi-machine systems for deriving a control law using gradient formulation without solving partial differential equations. The results validated on examples in the area of power system are used in transient stability analysis and enhancement.
{"title":"Decomposition of drift vector field: An application to multi-machine transient stability enhancement","authors":"S. Kulkarni, M. Parimi, S. Wagh, N. Singh","doi":"10.1109/PESGM.2016.7741829","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741829","url":null,"abstract":"Knowledge of a potential function is of prime importance in stability analysis of systems. In mechanical systems, energy is considered as potential function. Passivity based methods in literature aim in finding potential function, which may prove unsuccessful for certain class of systems e.g. biological systems. Unfortunately, no general rules exist for the construction of a Lyapunov function, so expertise and intuition of the designer on the specific system is required to define a candidate function. Present paper proposes a systematic method to generate a potential function after decomposing a drift vector field representing a general dynamical system. The method finds application in lossy multi-machine systems for deriving a control law using gradient formulation without solving partial differential equations. The results validated on examples in the area of power system are used in transient stability analysis and enhancement.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"201 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123222792","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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