Pub Date : 2011-12-01DOI: 10.1109/ICPES.2011.6156693
A. Akshatha, J. S. Rajan, G. Viswanath, D. Ravindara, C. Naidu, K. Singh
Corrosion of copper conductors in transformers is a major problem affecting the paper-oil insulation, ultimately leading to failure of transformers. Hence there is a growing concern on the issues like quality of oil, transformer design and its service conditions. Sulphur compounds are believed to be responsible for formation of semi conducting copper sulphide in paper insulation. This paper discusses the results of transformer oil drawn from different transformers of Power utilities in terms of total sulphur, mercaptan sulphur and DGA
{"title":"Estimation of sulphur compounds in transformer oil","authors":"A. Akshatha, J. S. Rajan, G. Viswanath, D. Ravindara, C. Naidu, K. Singh","doi":"10.1109/ICPES.2011.6156693","DOIUrl":"https://doi.org/10.1109/ICPES.2011.6156693","url":null,"abstract":"Corrosion of copper conductors in transformers is a major problem affecting the paper-oil insulation, ultimately leading to failure of transformers. Hence there is a growing concern on the issues like quality of oil, transformer design and its service conditions. Sulphur compounds are believed to be responsible for formation of semi conducting copper sulphide in paper insulation. This paper discusses the results of transformer oil drawn from different transformers of Power utilities in terms of total sulphur, mercaptan sulphur and DGA","PeriodicalId":158903,"journal":{"name":"2011 International Conference on Power and Energy Systems","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126041862","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 : 2011-12-01DOI: 10.1109/ICPES.2011.6156607
T. Kumar, V. Krishna, N. Ramana
This paper presents an analysis on dynamic performance of a three-area thermal system interconnected with AC tie-line parallel with HVDC link when subjected to parametric uncertainties. In this paper all the three areas consists of thermal power plants. The AC tie-line parallel with HVDC link is used as a system interconnection between all the three areas. Open transmission access and the evolution of more socialised companies for generation, transmission and distribution affects the formulation of Automatic Generation Control (AGC) problem. So, the traditional three area system is modified to take into account the effect of bilateral contracts on the dynamics. It has been observed that the dynamic response of three-area interconnected thermal plants through tie-line is sluggish and degraded when compared to the dynamic response of three area interconnected thermal power plants connected through an AC tie line Parallel with HVDC link.
{"title":"Improvement of dynamic performance of three area thermal system under deregulated environment using AC tieline parallel with HVDC link","authors":"T. Kumar, V. Krishna, N. Ramana","doi":"10.1109/ICPES.2011.6156607","DOIUrl":"https://doi.org/10.1109/ICPES.2011.6156607","url":null,"abstract":"This paper presents an analysis on dynamic performance of a three-area thermal system interconnected with AC tie-line parallel with HVDC link when subjected to parametric uncertainties. In this paper all the three areas consists of thermal power plants. The AC tie-line parallel with HVDC link is used as a system interconnection between all the three areas. Open transmission access and the evolution of more socialised companies for generation, transmission and distribution affects the formulation of Automatic Generation Control (AGC) problem. So, the traditional three area system is modified to take into account the effect of bilateral contracts on the dynamics. It has been observed that the dynamic response of three-area interconnected thermal plants through tie-line is sluggish and degraded when compared to the dynamic response of three area interconnected thermal power plants connected through an AC tie line Parallel with HVDC link.","PeriodicalId":158903,"journal":{"name":"2011 International Conference on Power and Energy Systems","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121830198","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 : 2011-12-01DOI: 10.1109/ICPES.2011.6156621
S. Rajasekar, Rajesh Gupta
This paper proposes a photovoltaic (PV) array supported five-level cascaded H-bridge multilevel inverter (CHBMLI) based shunt active power filter (SAPF). The combined system is used for power conditioning application to improve power quality in the distribution network. The photovoltaic supported CHBMLI makes attractive solution because this inverter need isolated dc source in the dc side of the each H-bridge. The SAPF is used to compensate both reactive and harmonic components of the current drawn by the non linear load. Additionally, it also balances the supply current for unbalanced load. In this paper it is shown that the PV based multilevel inverter configured SAPF not only compensates the harmonic current, reactive power and unbalancing but also injects real power whenever it is demanded in the distribution system. The compensation and power flow control in this paper is developed based on the instantaneous power theory. The simulation results presented in this paper evidently proves the compensation capabilities and real power injection. The simulation studies are carried out under power system computer aided design PSCAD/EMTDC 4.2 environment.
{"title":"Photovoltaic array based multilevel inverter for power conditioning","authors":"S. Rajasekar, Rajesh Gupta","doi":"10.1109/ICPES.2011.6156621","DOIUrl":"https://doi.org/10.1109/ICPES.2011.6156621","url":null,"abstract":"This paper proposes a photovoltaic (PV) array supported five-level cascaded H-bridge multilevel inverter (CHBMLI) based shunt active power filter (SAPF). The combined system is used for power conditioning application to improve power quality in the distribution network. The photovoltaic supported CHBMLI makes attractive solution because this inverter need isolated dc source in the dc side of the each H-bridge. The SAPF is used to compensate both reactive and harmonic components of the current drawn by the non linear load. Additionally, it also balances the supply current for unbalanced load. In this paper it is shown that the PV based multilevel inverter configured SAPF not only compensates the harmonic current, reactive power and unbalancing but also injects real power whenever it is demanded in the distribution system. The compensation and power flow control in this paper is developed based on the instantaneous power theory. The simulation results presented in this paper evidently proves the compensation capabilities and real power injection. The simulation studies are carried out under power system computer aided design PSCAD/EMTDC 4.2 environment.","PeriodicalId":158903,"journal":{"name":"2011 International Conference on Power and Energy Systems","volume":"494 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121954671","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 : 2011-12-01DOI: 10.1109/ICPES.2011.6156683
S. Karanki, M. Mishra, B. K. Kumar
The Unified Power Quality Conditioner (UPQC) is a custom power device, which mitigates voltage and current related power quality issues in the power distribution systems. In this paper, two new Voltage Source Inverter (VSI) topologies for UPQC application are proposed. The proposed topologies enables UPQC to have a reduced DC link voltage without compromising the compensation capability. These proposed topologies also help to match the DC link voltage requirement of the shunt and series active filters in the UPQC. In this paper the proposed UPQC topologies are compared with the existing topologies in the literature. A simulation study of the proposed topologies has been carried out and the results are presented.
UPQC (Unified Power Quality调节器)是一种定制的电源设备，用于缓解配电系统中与电压和电流相关的电能质量问题。本文提出了两种用于UPQC应用的电压源逆变器(VSI)拓扑结构。所提出的拓扑结构使UPQC能够在不影响补偿能力的情况下降低直流链路电压。这些提出的拓扑结构也有助于匹配UPQC中并联和串联有源滤波器的直流链路电压要求。本文将提出的UPQC拓扑与现有文献中的拓扑进行了比较。对所提出的拓扑进行了仿真研究，并给出了结果。
{"title":"Comparison of various Voltage Source Inverter based UPQC topologies","authors":"S. Karanki, M. Mishra, B. K. Kumar","doi":"10.1109/ICPES.2011.6156683","DOIUrl":"https://doi.org/10.1109/ICPES.2011.6156683","url":null,"abstract":"The Unified Power Quality Conditioner (UPQC) is a custom power device, which mitigates voltage and current related power quality issues in the power distribution systems. In this paper, two new Voltage Source Inverter (VSI) topologies for UPQC application are proposed. The proposed topologies enables UPQC to have a reduced DC link voltage without compromising the compensation capability. These proposed topologies also help to match the DC link voltage requirement of the shunt and series active filters in the UPQC. In this paper the proposed UPQC topologies are compared with the existing topologies in the literature. A simulation study of the proposed topologies has been carried out and the results are presented.","PeriodicalId":158903,"journal":{"name":"2011 International Conference on Power and Energy Systems","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131948464","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 : 2011-12-01DOI: 10.1109/ICPES.2011.6156623
N. Jayalakshmi, D. N. Gaonkar
This paper presents proportional-plus-integral (PI) controller based frequency regulation of isolated autonomous hybrid distributed generation system for sudden variation in load demand and wind. The developed hybrid system comprises of wind turbine generator (WTG), micro-turbine generator (MTG), fuel cell (FC), an aqua electrolyzer (AE) along with the energy storage device such as battery energy storage system (BESS). Further ultracapacitor (UC) as an alternative energy storage element is incorporated into the system for better performance. The generated hydrogen by an aqua electrolyzer is used as fuel for a fuel cell. The simulation results reported in the paper focused on frequency response for variable wind power, step load change and variable load.
{"title":"Performance study of isolated hybrid power system with multiple generation and energy storage units","authors":"N. Jayalakshmi, D. N. Gaonkar","doi":"10.1109/ICPES.2011.6156623","DOIUrl":"https://doi.org/10.1109/ICPES.2011.6156623","url":null,"abstract":"This paper presents proportional-plus-integral (PI) controller based frequency regulation of isolated autonomous hybrid distributed generation system for sudden variation in load demand and wind. The developed hybrid system comprises of wind turbine generator (WTG), micro-turbine generator (MTG), fuel cell (FC), an aqua electrolyzer (AE) along with the energy storage device such as battery energy storage system (BESS). Further ultracapacitor (UC) as an alternative energy storage element is incorporated into the system for better performance. The generated hydrogen by an aqua electrolyzer is used as fuel for a fuel cell. The simulation results reported in the paper focused on frequency response for variable wind power, step load change and variable load.","PeriodicalId":158903,"journal":{"name":"2011 International Conference on Power and Energy Systems","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133799170","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 : 2011-12-01DOI: 10.1109/ICPES.2011.6156660
A. B. Chowdhury, A. Kulhare, G. Raina
Our focus is on the impact that time delayed feedback can have on the stability and performance of a traditional power system model. Stability analysis has played an important role in power system models, however most of the models assume that any feedback is instantaneous. For example, in wide area measurement systems (WAMS) it would be important and realistic to incorporate time delays. Our focus will be on the impact time delayed feedback may have on the stability and performance of the single machine infinite bus (SMIB) power system model. For this model, we construct appropriate stability charts and bifurcation diagrams, which serve to exhibit the impact time delays may have on stability and performance. Our work is step towards a more systematic understanding of delayed feedback in power system models.
{"title":"A study of the SMIB power system model with delayed feedback","authors":"A. B. Chowdhury, A. Kulhare, G. Raina","doi":"10.1109/ICPES.2011.6156660","DOIUrl":"https://doi.org/10.1109/ICPES.2011.6156660","url":null,"abstract":"Our focus is on the impact that time delayed feedback can have on the stability and performance of a traditional power system model. Stability analysis has played an important role in power system models, however most of the models assume that any feedback is instantaneous. For example, in wide area measurement systems (WAMS) it would be important and realistic to incorporate time delays. Our focus will be on the impact time delayed feedback may have on the stability and performance of the single machine infinite bus (SMIB) power system model. For this model, we construct appropriate stability charts and bifurcation diagrams, which serve to exhibit the impact time delays may have on stability and performance. Our work is step towards a more systematic understanding of delayed feedback in power system models.","PeriodicalId":158903,"journal":{"name":"2011 International Conference on Power and Energy Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130687378","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 : 2011-12-01DOI: 10.1109/ICPES.2011.6156605
P. Sekhar, C. P. Jairam, T. Raghunatha, R. S. Kumar, K. Rao, V. Bharathi, Kiran. V. Madhugiri
This paper presents the impact of irrigation pump sets on base line AT&C loss, impact of revenue collection and collection efficiency in the Project Area. This paper also focuses on field experience of authors during the establishment of base line data for designated Project Areas under R-APDRP Programme. This paper also brought out sample base line parameters estimation. It also emphasizes problems in the field during collecting data and attempt to overcome the problems.
{"title":"The impact of IP sets for establishment of baseline data in power distribution of electric utilities under R-APDRP","authors":"P. Sekhar, C. P. Jairam, T. Raghunatha, R. S. Kumar, K. Rao, V. Bharathi, Kiran. V. Madhugiri","doi":"10.1109/ICPES.2011.6156605","DOIUrl":"https://doi.org/10.1109/ICPES.2011.6156605","url":null,"abstract":"This paper presents the impact of irrigation pump sets on base line AT&C loss, impact of revenue collection and collection efficiency in the Project Area. This paper also focuses on field experience of authors during the establishment of base line data for designated Project Areas under R-APDRP Programme. This paper also brought out sample base line parameters estimation. It also emphasizes problems in the field during collecting data and attempt to overcome the problems.","PeriodicalId":158903,"journal":{"name":"2011 International Conference on Power and Energy Systems","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114535289","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 : 2011-12-01DOI: 10.1109/ICPES.2011.6156679
P. Naidu, B. Raja
This paper presents a new voltage regulation system multi converter dynamic voltage restorer (MC-DVR), capable of simultaneous compensation for voltage in Multibus/multifeeder systems. In this configuration two voltage-source converters (VSC) exist. The system can be applied to adjacent feeders to compensate for supply-voltage on the main feeder and full compensation of supply-voltage imperfections on the other feeders. In the proposed configuration, all converters are connected back to back on the dc side and share a common dc-link capacitor. Therefore, power can be transferred from one feeder to adjacent feeders to compensate for sag. The performance of the MC-DVR as well as the adopted control algorithm is illustrated by simulation. The results obtained in MATLAB/SIMULINK on a two-bus/two-feeder system show the effectiveness of the proposed configuration.
{"title":"A new proposal for voltage regulation multi feeders/Multibus systems using MC-DVR","authors":"P. Naidu, B. Raja","doi":"10.1109/ICPES.2011.6156679","DOIUrl":"https://doi.org/10.1109/ICPES.2011.6156679","url":null,"abstract":"This paper presents a new voltage regulation system multi converter dynamic voltage restorer (MC-DVR), capable of simultaneous compensation for voltage in Multibus/multifeeder systems. In this configuration two voltage-source converters (VSC) exist. The system can be applied to adjacent feeders to compensate for supply-voltage on the main feeder and full compensation of supply-voltage imperfections on the other feeders. In the proposed configuration, all converters are connected back to back on the dc side and share a common dc-link capacitor. Therefore, power can be transferred from one feeder to adjacent feeders to compensate for sag. The performance of the MC-DVR as well as the adopted control algorithm is illustrated by simulation. The results obtained in MATLAB/SIMULINK on a two-bus/two-feeder system show the effectiveness of the proposed configuration.","PeriodicalId":158903,"journal":{"name":"2011 International Conference on Power and Energy Systems","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114223096","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 : 2011-12-01DOI: 10.1109/ICPES.2011.6156685
Bhim Singh, G. Bhuvaneswari, S. Madishetti
This paper presents power quality improvement at the utility interface for a Direct Torque Controlled (DTC) induction motor drive by making use of a Minnesota rectifier. The proposed Minnesota rectifier for a 2.2 kW drive is designed, modeled and simulated in MATLAB/Simulink platform. The design of the proposed Minnesota rectifier is developed along with the necessary modifications required for making it suitable for retrofit applications, where presently a 6-pulse diode bridge rectifier is used. The performance parameters of the DTC drive fed by a 6-pulse uncontrolled converter is compared with the one fed by Minnesota rectifier for variable load conditions. The results show that the THD and power factor at the ac mains are improved perceivably even with the magnetic rating being as low as 40.94% of the drive rating.
{"title":"Power quality improvement in DTC based induction motor drive using Minnesota rectifier","authors":"Bhim Singh, G. Bhuvaneswari, S. Madishetti","doi":"10.1109/ICPES.2011.6156685","DOIUrl":"https://doi.org/10.1109/ICPES.2011.6156685","url":null,"abstract":"This paper presents power quality improvement at the utility interface for a Direct Torque Controlled (DTC) induction motor drive by making use of a Minnesota rectifier. The proposed Minnesota rectifier for a 2.2 kW drive is designed, modeled and simulated in MATLAB/Simulink platform. The design of the proposed Minnesota rectifier is developed along with the necessary modifications required for making it suitable for retrofit applications, where presently a 6-pulse diode bridge rectifier is used. The performance parameters of the DTC drive fed by a 6-pulse uncontrolled converter is compared with the one fed by Minnesota rectifier for variable load conditions. The results show that the THD and power factor at the ac mains are improved perceivably even with the magnetic rating being as low as 40.94% of the drive rating.","PeriodicalId":158903,"journal":{"name":"2011 International Conference on Power and Energy Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114302120","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 : 2011-12-01DOI: 10.1109/ICPES.2011.6156667
A. Kumar, P. Raj
This paper explores the application of artificial intelligence on solving the power quality problems by using the shunt active power filter strategy for three phase three wire distribution system. The unit vector template generation control technique is modeled as current controller for the shunt active power filter strategy. The proportional and integral (PI) controller is designed to minimize error between the actual and the reference DC voltage of shunt active power filter strategy. The transient period and peak overshoot of DC bus voltage using a PI controller is observed to be higher in initial and load change conditions. The artificial neural network is a powerful tool used to generate the current signal with very low oscillation and faster settling time. In this paper, a new neural learning algorithm (NAL) is proposed for the current controller of the shunt active power filter strategy. The performance of the proposed neural learning algorithm is extensively analyzed of diode rectifier RL non linear load with respect to two different operating conditions. The proposed system is designed with MATLAB/Simulink environment.
{"title":"Neural learning algorithm based power quality enhancement for three phase three wire distribution system utilizing shunt active power filter strategy","authors":"A. Kumar, P. Raj","doi":"10.1109/ICPES.2011.6156667","DOIUrl":"https://doi.org/10.1109/ICPES.2011.6156667","url":null,"abstract":"This paper explores the application of artificial intelligence on solving the power quality problems by using the shunt active power filter strategy for three phase three wire distribution system. The unit vector template generation control technique is modeled as current controller for the shunt active power filter strategy. The proportional and integral (PI) controller is designed to minimize error between the actual and the reference DC voltage of shunt active power filter strategy. The transient period and peak overshoot of DC bus voltage using a PI controller is observed to be higher in initial and load change conditions. The artificial neural network is a powerful tool used to generate the current signal with very low oscillation and faster settling time. In this paper, a new neural learning algorithm (NAL) is proposed for the current controller of the shunt active power filter strategy. The performance of the proposed neural learning algorithm is extensively analyzed of diode rectifier RL non linear load with respect to two different operating conditions. The proposed system is designed with MATLAB/Simulink environment.","PeriodicalId":158903,"journal":{"name":"2011 International Conference on Power and Energy Systems","volume":"180 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114421267","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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