Pub Date : 2018-09-01DOI: 10.1109/BULEF.2018.8646953
Valentin Kolev, S. Sulakov
The penetration of large-scale wind farms causes a number of challenges. The market participants have to deal the wind power output for different market time horizon in order to minimize the deviations of their trading schedules. In order to control the balance between production and consumption, transmission system operators need information in advance, concerning wind generation, to prepare necessary types of reserves and to activate them in real time. The wind power forecasting is frequently identified as an important tool to address the variability and uncertainty of the wind power and to more efficiently operate the power systems with large wind power penetrations. In this report is presented the experience of the implementation of a forecasting model suitable for day-ahead and intraday markets.
{"title":"Forecasting the hourly power output of wind farms for day-ahead and intraday markets","authors":"Valentin Kolev, S. Sulakov","doi":"10.1109/BULEF.2018.8646953","DOIUrl":"https://doi.org/10.1109/BULEF.2018.8646953","url":null,"abstract":"The penetration of large-scale wind farms causes a number of challenges. The market participants have to deal the wind power output for different market time horizon in order to minimize the deviations of their trading schedules. In order to control the balance between production and consumption, transmission system operators need information in advance, concerning wind generation, to prepare necessary types of reserves and to activate them in real time. The wind power forecasting is frequently identified as an important tool to address the variability and uncertainty of the wind power and to more efficiently operate the power systems with large wind power penetrations. In this report is presented the experience of the implementation of a forecasting model suitable for day-ahead and intraday markets.","PeriodicalId":416020,"journal":{"name":"2018 10th Electrical Engineering Faculty Conference (BulEF)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126432881","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 : 2018-09-01DOI: 10.1109/BULEF.2018.8646932
Tsvetomir Stoyanov, R. Spasov
This paper present the results from a study of two-phase V-shaped permanent magnet synchronous machines, used in hybrid cars. The analysis based on the main harmonic of the magnetic flux density in the air gap and emf. Also has been made a comparison between this machine and synchronous machines with three-phase winding (both machines have the same geometry), used Clarke transformation. The comparison of the electromagnetic torque produced by both machines is presented. The analysis is performed by finite element magnetic field modeling and program modules for of magnetic flux density and emf.
{"title":"Analysis of Two-phase Permanent Magnet Synchronous Machines Used for Hybrid Vehicles","authors":"Tsvetomir Stoyanov, R. Spasov","doi":"10.1109/BULEF.2018.8646932","DOIUrl":"https://doi.org/10.1109/BULEF.2018.8646932","url":null,"abstract":"This paper present the results from a study of two-phase V-shaped permanent magnet synchronous machines, used in hybrid cars. The analysis based on the main harmonic of the magnetic flux density in the air gap and emf. Also has been made a comparison between this machine and synchronous machines with three-phase winding (both machines have the same geometry), used Clarke transformation. The comparison of the electromagnetic torque produced by both machines is presented. The analysis is performed by finite element magnetic field modeling and program modules for of magnetic flux density and emf.","PeriodicalId":416020,"journal":{"name":"2018 10th Electrical Engineering Faculty Conference (BulEF)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124739047","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 : 2018-09-01DOI: 10.1109/BULEF.2018.8646941
A. Tsolov
Expanding possible ports and communication devices would make SCADA more convenient. Possible ways of wired and wireless connectivity are discussed through transitions between RS485/RS232/USB and Xbee wireless modules, together with the Bluetooth module HC-08, which allows connection to a smartphone. The connection to an operator station is through a USB port. A dedicated USB to UART converter has been developed, which incorporates additional ASCII conversion functions, as well as standard serial communication protocols. As a result, much higher reliability and flexibility in SCADA performance has been achieved, especially in distributed-type systems with multi-master architecture.
{"title":"Multi-channel interface converter","authors":"A. Tsolov","doi":"10.1109/BULEF.2018.8646941","DOIUrl":"https://doi.org/10.1109/BULEF.2018.8646941","url":null,"abstract":"Expanding possible ports and communication devices would make SCADA more convenient. Possible ways of wired and wireless connectivity are discussed through transitions between RS485/RS232/USB and Xbee wireless modules, together with the Bluetooth module HC-08, which allows connection to a smartphone. The connection to an operator station is through a USB port. A dedicated USB to UART converter has been developed, which incorporates additional ASCII conversion functions, as well as standard serial communication protocols. As a result, much higher reliability and flexibility in SCADA performance has been achieved, especially in distributed-type systems with multi-master architecture.","PeriodicalId":416020,"journal":{"name":"2018 10th Electrical Engineering Faculty Conference (BulEF)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128963031","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 : 2018-09-01DOI: 10.1109/BULEF.2018.8646942
Кostadin Milanov, H. Antchev
The present paper proposes an addition to the well-known methods of protection from increased voltage in powerful direct-current electric power supply grids through an electronic circuit of a thyristor short-circuit device. The work proposes dependencies for design and studies the circuit with two types of disturbances – stepwise and linear in time.
{"title":"Fast-acting protection of a semiconductor converter by means of short-circuiting thyristor","authors":"Кostadin Milanov, H. Antchev","doi":"10.1109/BULEF.2018.8646942","DOIUrl":"https://doi.org/10.1109/BULEF.2018.8646942","url":null,"abstract":"The present paper proposes an addition to the well-known methods of protection from increased voltage in powerful direct-current electric power supply grids through an electronic circuit of a thyristor short-circuit device. The work proposes dependencies for design and studies the circuit with two types of disturbances – stepwise and linear in time.","PeriodicalId":416020,"journal":{"name":"2018 10th Electrical Engineering Faculty Conference (BulEF)","volume":"130 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127074935","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 : 2018-09-01DOI: 10.1109/BULEF.2018.8646955
P. Stoev, I. Angelov, Nikolay Matanov
This paper presents the operation of lighting control system with LED luminaires. A lighting system primarily powered by Photovoltaic panels has been studied and in order to ensure uninterrupted operation, has been reserved by the LV electrical network. Such a system can be used in tunnel lighting systems to power part of the adaptation and / or permanent lighting system. Both lighting systems work during the day, with the overall adaptation brightness being greatest during the interval 11am – 2pm when the PV string power generated reaches its peak. In order to achieve more significant economic effect, neither energy storage elements, nor maximum power point tracking controller have been added. The principle of control on the luminaires has been presented according to the photovoltaic plant output voltage variation. A simulation model has been developed in Matlab aiming to simulate and analyze the system’s performance. The system’s characteristic have been presented for the entire range of photovoltaics operation.
{"title":"Dimming Control of LED Lighting Fixtures Powered with Photovoltaic Modules","authors":"P. Stoev, I. Angelov, Nikolay Matanov","doi":"10.1109/BULEF.2018.8646955","DOIUrl":"https://doi.org/10.1109/BULEF.2018.8646955","url":null,"abstract":"This paper presents the operation of lighting control system with LED luminaires. A lighting system primarily powered by Photovoltaic panels has been studied and in order to ensure uninterrupted operation, has been reserved by the LV electrical network. Such a system can be used in tunnel lighting systems to power part of the adaptation and / or permanent lighting system. Both lighting systems work during the day, with the overall adaptation brightness being greatest during the interval 11am – 2pm when the PV string power generated reaches its peak. In order to achieve more significant economic effect, neither energy storage elements, nor maximum power point tracking controller have been added. The principle of control on the luminaires has been presented according to the photovoltaic plant output voltage variation. A simulation model has been developed in Matlab aiming to simulate and analyze the system’s performance. The system’s characteristic have been presented for the entire range of photovoltaics operation.","PeriodicalId":416020,"journal":{"name":"2018 10th Electrical Engineering Faculty Conference (BulEF)","volume":"08 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127441332","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 : 2018-09-01DOI: 10.1109/BULEF.2018.8646961
Valentin Kolev, Angel Georgiev, S. Sulakov
The reliability of an electric power system is defined as the probability that the power system will perform the function of delivering electric energy to consumers on a continuous basis with acceptable service quality. The power system can be divided into appropriate subsystems or functional areas that can be analysed separately – generation, transmission and distribution. The basic modeling approach for the power system adequacy assessment consists of three parts – generation model, load model and power balance model. As a final step after creating these models, system adequacy index is calculated. Probabilistic models of generation, load and power balance are used in this paper concerning short and medium term adequacy forecast.
{"title":"Probabilistic modelling and evaluation of system adequacy","authors":"Valentin Kolev, Angel Georgiev, S. Sulakov","doi":"10.1109/BULEF.2018.8646961","DOIUrl":"https://doi.org/10.1109/BULEF.2018.8646961","url":null,"abstract":"The reliability of an electric power system is defined as the probability that the power system will perform the function of delivering electric energy to consumers on a continuous basis with acceptable service quality. The power system can be divided into appropriate subsystems or functional areas that can be analysed separately – generation, transmission and distribution. The basic modeling approach for the power system adequacy assessment consists of three parts – generation model, load model and power balance model. As a final step after creating these models, system adequacy index is calculated. Probabilistic models of generation, load and power balance are used in this paper concerning short and medium term adequacy forecast.","PeriodicalId":416020,"journal":{"name":"2018 10th Electrical Engineering Faculty Conference (BulEF)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124335146","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 : 2018-09-01DOI: 10.1109/BULEF.2018.8646950
Nikolay Matanov, H. Penev, N. Ivanov
Shunt Passive Filters (SPF) are an economically well-founded and technically effective solution for reactive power compensation and solving the problems with harmonics, caused by non-linear loads, in the electrical power systems of medium and large industrial enterprises. The elements parameters definition for each SPF is a specific task that is specifically solved for each power supply system.This paper presents a methodology, algorithm and software program for designing Medium Voltage (MV) filter-compensating devices. Particular attention is paid to the determination and distribution of the compensating power among the different harmonic filters. The results from this work can be useful in designing and optimizing the efficiency of the medium voltage shunt passive filters.
{"title":"Determination of the capacitive output power of shunt passive filters","authors":"Nikolay Matanov, H. Penev, N. Ivanov","doi":"10.1109/BULEF.2018.8646950","DOIUrl":"https://doi.org/10.1109/BULEF.2018.8646950","url":null,"abstract":"Shunt Passive Filters (SPF) are an economically well-founded and technically effective solution for reactive power compensation and solving the problems with harmonics, caused by non-linear loads, in the electrical power systems of medium and large industrial enterprises. The elements parameters definition for each SPF is a specific task that is specifically solved for each power supply system.This paper presents a methodology, algorithm and software program for designing Medium Voltage (MV) filter-compensating devices. Particular attention is paid to the determination and distribution of the compensating power among the different harmonic filters. The results from this work can be useful in designing and optimizing the efficiency of the medium voltage shunt passive filters.","PeriodicalId":416020,"journal":{"name":"2018 10th Electrical Engineering Faculty Conference (BulEF)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124804182","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 : 2018-09-01DOI: 10.1109/BULEF.2018.8646946
Valentin Kolev, S. Sulakov
The hourly power output forecasting of the photovoltaics is crucial for scheduling and dispatching purposes in order to minimize imbalances arisen in settlement process and to precisely define the required balancing reserves. The photovoltaics are mainly connected to the distribution grid. Their production creates different levels and directions of power flows during the day that is important for the grid assessments, including maintenance scheduling. In this report is presented a forecasting model suitable for markets perspectives and security assessments of the grid.
{"title":"Short-term power output forecasting of the photovoltaics in Bulgaria","authors":"Valentin Kolev, S. Sulakov","doi":"10.1109/BULEF.2018.8646946","DOIUrl":"https://doi.org/10.1109/BULEF.2018.8646946","url":null,"abstract":"The hourly power output forecasting of the photovoltaics is crucial for scheduling and dispatching purposes in order to minimize imbalances arisen in settlement process and to precisely define the required balancing reserves. The photovoltaics are mainly connected to the distribution grid. Their production creates different levels and directions of power flows during the day that is important for the grid assessments, including maintenance scheduling. In this report is presented a forecasting model suitable for markets perspectives and security assessments of the grid.","PeriodicalId":416020,"journal":{"name":"2018 10th Electrical Engineering Faculty Conference (BulEF)","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114211086","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 : 2018-09-01DOI: 10.1109/BULEF.2018.8646947
S. Pappas
This paper tackles the problem of the long-term prediction of the electrical energy consumption with three different prediction approaches using real data. The first method combines the well-established multimodel partitioning filter (MMPF) implementing extended Kalman filters (EKF) with Support Vector Machines (SVM), the second is a hybrid method of MMPF and Genetic Algorithms (G.A) and the last method implements an artificial multilayer layer feed-forward neural network (ANN). The accuracy of a long-term forecasting (considering a time interval greater than one year) is of great importance, since it contributes to the planning and expansion of a country’s electric power system reliably and economically. Various factors affecting long term prediction such as the existing installed capacity, the annual average ambient temperature and humidity, the annual electric energy consumption per capita, the energy consumption per person and the gross domestic product (GDP) were considered in all three approaches. The results indicate that all methods are reliable, however the combination of MMPF and SVM provides a more accurate long-term load forecasting in terms of absolute percentage error. Therefore the system administrator based on its forecasts will able to use the available resources for planning the construction of new generation facilities and also expanding the transmission line grid using a cost effective plan.
{"title":"Application and comparison of adaptive methods for the long term prediction of the electrical energy consumption in Greece","authors":"S. Pappas","doi":"10.1109/BULEF.2018.8646947","DOIUrl":"https://doi.org/10.1109/BULEF.2018.8646947","url":null,"abstract":"This paper tackles the problem of the long-term prediction of the electrical energy consumption with three different prediction approaches using real data. The first method combines the well-established multimodel partitioning filter (MMPF) implementing extended Kalman filters (EKF) with Support Vector Machines (SVM), the second is a hybrid method of MMPF and Genetic Algorithms (G.A) and the last method implements an artificial multilayer layer feed-forward neural network (ANN). The accuracy of a long-term forecasting (considering a time interval greater than one year) is of great importance, since it contributes to the planning and expansion of a country’s electric power system reliably and economically. Various factors affecting long term prediction such as the existing installed capacity, the annual average ambient temperature and humidity, the annual electric energy consumption per capita, the energy consumption per person and the gross domestic product (GDP) were considered in all three approaches. The results indicate that all methods are reliable, however the combination of MMPF and SVM provides a more accurate long-term load forecasting in terms of absolute percentage error. Therefore the system administrator based on its forecasts will able to use the available resources for planning the construction of new generation facilities and also expanding the transmission line grid using a cost effective plan.","PeriodicalId":416020,"journal":{"name":"2018 10th Electrical Engineering Faculty Conference (BulEF)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129826642","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 : 2018-09-01DOI: 10.1109/BULEF.2018.8646940
Yavor Lozanov, S. Tzvetkova, Angel Petleshkov
The results from a study of the influence of the set measurement parameters on the temperature readings obtained during the thermographic study of a pumping station electrical equipment are presented in the paper. An analysis of the obtained results has been made taking into account the dependence of the obtained characteristics on the temperature of the tested object.
{"title":"Influence of the measurement parameters in thermographic study of electrical equipment","authors":"Yavor Lozanov, S. Tzvetkova, Angel Petleshkov","doi":"10.1109/BULEF.2018.8646940","DOIUrl":"https://doi.org/10.1109/BULEF.2018.8646940","url":null,"abstract":"The results from a study of the influence of the set measurement parameters on the temperature readings obtained during the thermographic study of a pumping station electrical equipment are presented in the paper. An analysis of the obtained results has been made taking into account the dependence of the obtained characteristics on the temperature of the tested object.","PeriodicalId":416020,"journal":{"name":"2018 10th Electrical Engineering Faculty Conference (BulEF)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124590921","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：